## Proposal Cover Sheet

NASA Research Announcement 99-OES-04

Proposal No. ­\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_ (Leave Blank for
NASA Use)

LoI Reference No. 357

Satellite-Sunphotometer Studies of Aerosol, Water Vapor and Ozone Roles

**in Climate-Chemistry-Biosphere Interactions**

**Principal Investigator:**

Philip B. Russell Date

Atmospheric Chemistry and Dynamics Branch

NASA Ames Research Center, MS 245-5

Moffett Field, CA 94035-1000

<prussell@mail.arc.nasa.gov>, Phone: 650-604-5404. Fax: 650-604-6779

Co-Investigators:

Beat Schmid, Bay Area Environmental Research Institute (Tel.
650-604-5933, bschmid@mail.arc.nasa.gov)

Jens Redemann, Bay Area Environmental Research Institute (Tel.
650-604-6259, <jredemann@mail.arc.nasa.gov>)

John M. Livingston, SRI International (Tel. 650-604-3386,
<jlivingston@mail.arc.nasa.gov>)

Robert W. Bergstrom, Bay Area Environmental Research Institute (Tel.
650-604-6261, <bergstro@sky.arc.nasa.gov>)

Kenneth J. Voss, University of Miami (Tel. 305-284-2323,
<voss@physics.miami.edu>)

Didier Tanre, Universite des Sciences et Technologies de Lille (Tel. 33
(0)3 20 33 70 33,

<Didier.Tanre@univ-lille1.fr>)

Jay R. Herman, NASA Goddard Space Flight Center (Tel. 301-614-6039,
herman@tparty.gsfc.nasa.gov)

Budget:

1st Year: [\$225K]{.underline} 2nd Year [\$267K]{.underline} 3rd Year:
[\$309K]{.underline} 4th Year: Total: [\$800K]{.underline}

(OVWST Only)

##### Program Element *(select one or more)*

\_\_\_\_ Global Modeling and Analysis Program (GMAP)

[\_X\_]{.underline} Atmospheric Chemistry Modeling and Analysis Program
(ACMAP)

\_\_\_\_ Physical Oceanography Research and Analysis Program (PORAP)

\_\_\_\_ Ocean Vector Winds Science Team (OVWST)

\_\_\_\_ Pathfinder Data Set and Associated Science Program (PDSP)

[\_X\_]{.underline} EOS Interdisciplinary Science Program (EOS/IDS)

**Reviewed by:**

R. Stephen Hipskind Date

**Authorizing Official:**

Estelle P. Condon, Chief Date

Earth Science Division

NASA Ames Research Center

## TABLE OF CONTENTS

[Page]{.underline}

LIST OF TABLES AND ILLUSTRATIONS i

LIST OF ACRONYMS ii

ABSTRACT iii

PROGRAM RELEVANCE iii

1 OBJECTIVES, EXPECTED SIGNIFICANCE, AND GENERAL APPROACH 1

2 BACKGROUND: FIELD CAMPAIGNS AND EXPECTED ROLES OF SATELLITE AND
AIRBORNE SUNPHOTOMETER DATA PRODUCTS 2

> 2.1 SAFARI 2000 2
>
> 2.2 African Dust Plume and Water-Leaving Radiance Opportunities on
> SAFARI 2000 Transits 7
>
> 2.3 ACE Asia Survey and Evolution Component 7
>
> 2.4 Other Possible Experiments 10

3 PROPOSED RESEARCH 10

> 3.1 Year One: Tasks 1.1 -- 1.6 10
>
> 3.2 Years Two and Three: Tasks 2.1 -- 2.6 13

4 SCHEDULE 16

5 REFERENCES 16

6 BUDGET 22

7 STAFFING, RESPONSIBILITIES, AND VITAE 25

8 CURRENT SUPPORT 35

**TABLE**

  ----- --------------------------------------------------------------- ----
  1\.   Satellites, sensors, data products, and planned field campaigns 38
        relevant to this proposal                                       

  ----- --------------------------------------------------------------- ----

**ILLUSTRATIONS**

  ----- --------------------------------------------------------------- ----
  1\.   Latitude transects of aerosol optical depth and Ångström        F1
        exponent derived from the AATS-6 sunphotometer aboard the UW    
        C-131A, from ATSR-2, and from AVHRR.                            

  2\.   Aerosol optical thickness measured by sunphotometer (AATS-6)    F2
        aboard the C-131A aircraft and derived from MAS data as a       
        function of wavelength.                                         

  3\.   Aerosol optical depths measured in ACE 2 by AATS-6 on the R/V   F3
        Vodyanitskiy, AATS-14 on the Pelican aircraft, and AVHRR on the 
        NOAA-14 Satellite.                                              

  4\.   Profiles of aerosol optical depth and extinction at selected    F4
        AATS-14 wavelengths (380, 500, 864 and 1558 nm) measured in ACE 
        2.                                                              

  5\.   Comparison of aerosol optical depth spectra for the marine      F5
        boundary layer during a Pelican flight in ACE 2.                

  6\.   Marine boundary layer aerosol size distributions from in situ   F6
        measurements and inverted from AATS-14 extinction spectra       
        measured on Pelican flight tf15 in ACE 2.                       
  ----- --------------------------------------------------------------- ----

+---+---------------------------------------------------------------+---+
|   | **ILLUSTRATIONS** (Cont'd)                                    | # |
|   |                                                               | # |
|   |                                                               | # |
|   |                                                               | # |
|   |                                                               | # |
|   |                                                               | # |
|   |                                                               |   |
|   |                                                               | P |
|   |                                                               | a |
|   |                                                               | g |
|   |                                                               | e |
+---+---------------------------------------------------------------+---+
| 7 | Profiles of the columnar water vapor and water vapor density  | F |
| \ | measured in ACE 2 by AATS-14 and in situ sensor.              | 7 |
| . |                                                               |   |
+---+---------------------------------------------------------------+---+
| 8 | Scatter diagram of columnar water vapor calculated from       | F |
| \ | radiosonde measurements and from AATS-6 measurements during   | 8 |
| . | ACE 2.                                                        |   |
+---+---------------------------------------------------------------+---+
| 9 | Aerosol single-scattering albedo profiles determined for      | F |
| \ | TARFOX flight 1728 (July 17, 1996) by two techniques.         | 9 |
| . |                                                               |   |
+---+---------------------------------------------------------------+---+
| 1 | Comparison between aerosol-induced change in solar flux       | F |
| 0 | derived from C-130 pyranometer measurements (data points) and | 1 |
| \ | calculations (curves).                                        | 0 |
| . |                                                               |   |
+---+---------------------------------------------------------------+---+
| 1 | Aerosol-induced change in net shortwave flux at tropopause    | F |
| 1 | calculated from satellite maps of aerosol optical depth and   | 1 |
| \ | aerosol intensive properties from TARFOX.                     | 1 |
| . |                                                               |   |
+---+---------------------------------------------------------------+---+
| 1 | Channel wavelengths of Ames Airborne Tracking Sunphotometers  | F |
| 2 | (AATS-6 and AATS-14) in relation to atmospheric spectra.      | 1 |
| \ |                                                               | 2 |
| . |                                                               |   |
+---+---------------------------------------------------------------+---+

**ACRONYMS**

  -------------- --------------------------------------------------- -----
  AA-SEC         ACE Asia Survey and Evolution Component             

  AATS-6         6-channel Ames Airborne Tracking Sunphotometer      

  AATS-14        14-channel Ames Airborne Tracking Sunphotometer     

  ACE            Aerosol Characterization Experiment                 

  ADEOS          Advanced Earth Observing Satellite                  

  ASTER          Advanced Spaceborne Thermal Emission and Reflection 
                 Radiometer                                          

  ATSR           Along-Track Scanning Radiometer                     

  AVHRR          Advanced Very High Resolution Radiometer            

  BOREAS         Boreal Ecosystem-Atmosphere Study                   

  CERES          Clouds and the Earth's Radiant Energy System        

  EOS            Earth Observing System                              

  FIFE           First ISLSCP Field Experiment                       

  GOES           Geostationary Operational Environmental Satellite   

  HAPEX-Sahel    Hydrologic-Atmospheric Pilot Experiment in the      
                 Sahel                                               

  ISLSCP         International Satellite Land Surface Climatology    
                 Project                                             

  LITE           Lidar In-space Technology Experiment                

  OES            Office of Earth Science                             

  MAS            MODIS Airborne Simulator                            

  MISR           Multi-angle Imaging Spectro-Radiometer              

  MODIS          Moderate-resolution Imaging Spectroradiometer       

  MOPITT         Measurements of Pollution in the Troposphere        

  PICASSO-CENA   Pathfinder Instruments for Cloud and Aerosol        
                 Spaceborne Observations -- Climatologie Etendue des 
                 Nuages et des Aerosols                              

  POLDER         Polarization and Directionality of the Earth's      
                 Reflectances                                        

  SAFARI         Southern African Fire-Atmosphere Regional Science   
                 Initiative                                          

  SAGE           Stratospheric Aerosol and Gas Experiment            

  SCAR-B         Smoke, Clouds And Radiation experiment in Brazil    

  SeaWiFS        Sea-viewing Wide-Field-of-view Sensor               

  SEC            Survey and Evolution Component \[of ACE Asia\]      

  SSFR           Spectral Solar Flux Radiometer                      

  TARFOX         Tropospheric Aerosol Radiative Forcing              
                 Observational Experiment                            

  TOMS           Total Ozone Mapping Spectrometer                    

  TRACE-A        Transport and Chemistry Near the Equator-Atlantic   

  TRACE-P        Transport and Chemical Evolution over the Pacific   
  -------------- --------------------------------------------------- -----

Satellite-Sunphotometer Studies of Aerosol, Water Vapor and Ozone Roles

**in Climate-Chemistry-Biosphere Interactions**

**ABSTRACT**: We propose modeling and integrated analyses of suborbital
and satellite data to address impacts of biomass smokes, Asian and
African soil dust, and other tropospheric aerosols, water vapor, and
ozone on the Earth's radiation budget and on remote measurements of
ocean color and terrestrial ecology. Research will focus on analysis of
data from international multiplatform field campaigns such as SAFARI
2000 and ACE Asia. Data from airborne sunphotometers and other airborne
and surface remote and in situ measurements will be combined in closure
studies that test and improve models of complex multicomponent
tropospheric aerosols and their interactions with water vapor and
radiation. Pre-campaign modeling and algorithm development will focus on
providing realtime analysis and display capabilities useful for studies
of aerosol evolution and mass budgets, including flight planning and
direction. During and after campaigns suborbital data and models will be
used to validate satellite measurements of aerosols, water vapor, and
ozone, plus atmospheric corrections of satellite ocean color and
terrestrial measurements. They will then be used to supplement the
satellite data with other information needed for studies of aerosol
physicochemical evolution and radiative-climatic effects. In particular,
satellite maps of aerosol properties will be combined with suborbital
data in radiative transfer models to assess aerosol effects on radiation
balance and heating rates, both at the surface and aloft.

**PROGRAM RELEVANCE**: This proposal is aimed primarily at the EOS
Interdisciplinary Science Program (EOS/IDS) and secondarily at the
Atmospheric Chemistry Modeling and Analysis Program (ACMAP). It
addresses three of the five priority research themes of NASA's Earth
Science Enterprise cited in the NRA. Specifically, within the Climate
Variability and Change theme, it addresses understanding, modeling, and
predicting climate change caused by three radiatively active
constituents: aerosols, water vapor, and ozone; within the Atmospheric
Chemistry theme it addresses tropospheric pollution and its transport
and transformations over regional-to-global scales; and within the
Ecosystems and Global Carbon Cycle theme it addresses the remote
measurement of terrestrial and marine ecosystems via the removal of
atmospheric effects from those measurements. The proposal also addresses
several of the cross-disciplinary subjects listed in the EOS/IDS section
of the NRA (Appendix A, Section 2.f): Atmospheric chemistry and climate
(specifically, tropospheric aerosol effects on radiative balance),
Land-climate feedback (specifically, the impact of biomass fires on
biogeochemical cycling and remote measurements of ecosystem processes),
and Coastal region processes (specifically, the impact of biomass
burning and airborne soil dust on coastal waters and their remote
measurement). It will use data from such multi-national, multi-agency
field campaigns as SAFARI-2000 and the Aerosol Characterization
Experiment (ACE) Asian mission cited in the ACMAP section of the NRA
(Appendix A, Section 2.b). The proposed research will combine airborne
and surface-based measurements from those campaigns to validate and
complement atmospheric, oceanic, and terrestrial data products from such
satellites and sensors as EOS Terra, TOMS, ADEOS II/POLDER, and SeaWiFS.
The combined satellite and suborbital data will be used to drive models
of aerosol and water vapor effects on radiation budgets and remote
measurements and also to test and advance models of aerosol optical
properties and their relation to aerosol chemical and physical
processes.

1.  **OBJECTIVES, EXPECTED SIGNIFICANCE, AND GENERAL APPROACH**

The overall objective of the proposed research is to improve
understanding of interactions between chemistry, climate and the
biosphere, and to advance remote measurement science, by combining data
from space, aircraft and the surface in innovative ways. Questions to be
addressed include the impact of complex tropospheric aerosols on
radiative balance, the effects of water in vapor and condensed phases on
radiation and aerosol properties, the role of biomass burning in
land-climate interactions, and the effects of atmospheric properties on
remote measurements of ocean color, terrestrial ecosystems, and
associated biogeochemical processes. The research will stress analysis
of data from multiagency field campaigns (e.g., SAFARI-2000, ACE Asia)
that combine airborne sunphotometry of aerosols, water vapor and ozone
with in situ, satellite, and other remote measurements.

Satellite measurement science is advancing rapidly (e.g., Kaufman et
al., 1997; Gordon et al., 1997; King et al., 1999). Recently TOMS
measurements, designed to monitor ozone, were shown to contain valuable
information on aerosol geographical distributions (Herman et al., 1997)
which have been used to find an increase in biomass burning smoke in the
African savanna regions during the 1990s (Hsu et al., 1999). SeaWiFS,
developed to provide ocean color data products for the study of marine
biogeochemical processes, produces an aerosol data product from its
atmospheric correction algorithm, and it has been used to document
transport of Asian dust plumes across the Pacific Ocean (Kuring et al.,
1999). With the upcoming launch of EOS Terra, new instruments like MODIS
and MISR will provide improved measurement capabilities and
unprecedented volumes of data on the atmosphere, land, ocean, and
radiative processes (e.g., Tanre et al., 1997; Wanner et al., 1997). The
launch of POLDER on ADEOS II will add more capabilities (e.g., Leroy et
al., 1997). Extracting the full potential from these satellite data
requires correlative suborbital data, not only to validate the satellite
measurements (e.g., Clark et al., 1997; Fraser et al., 1997; Vermote et
al., 1997), but to supply information not obtainable from space.

Airborne sunphotometry, a desired component of planned multinational
field campaigns, has the potential to play a strong role in providing
both these types of correlative data. The strength of airborne
sunphotometry is its unique ability to measure four-dimensional fields
of aerosol optical depth and extinction spectra (near UV - visible -
near IR) and water vapor and ozone columns, all at times and locations
chosen by the experimenter, including coincidences with satellite
overpasses. Data from airborne sunphotometer transects over the ocean,
the ocean-land interface, and other surfaces of varying reflectivities,
as well as from transects across gradients of aerosol, water vapor, and
ozone columns, can be used to test satellite retrievals of aerosols,
ocean color, and land surface properties under a wide range of
conditions and degrees of difficulty. Furthermore, data from airborne
sunphotometer vertical profiles show the relative altitudes of aerosol,
water vapor, Rayleigh, and ozone extinction. When combined with
simultaneous airborne measurements of radiative fluxes, such
sunphotometer vertical profile measurements can provide information on
absorption by the ambient aerosol (undistorted by sampling processes),
which can be compared to in situ measurements of aerosol scattering and
absorption, to judge their mutual consistency and assess potential
artifacts of each measurement processes. Such vertical profile studies
are important not only to aerosol effects on radiation budgets and
climate, but to atmospheric corrections of ocean color measurements
(e.g., Clark et al., 1997), which are particularly sensitive to aerosol
vertical distribution when the aerosols are absorbing (e.g., in plumes
of smoke, industrial haze, and/or soil dust---see, e.g., Nakajima and
Higurashi, 1997; Nakajima et al., 1989).

This proposal requests funding for studies that will exploit the full
potential of airborne sunphotometry by permitting the interdisciplinary,
multi-instrument analyses that typically do not fit within the
mission/measurement funding for such multinational campaigns. The
potential is exemplified by the contributions to a variety of
disciplines made by previous measurements and analyses using the Ames
Airborne Tracking Sunphotometers (AATS-6 and AATS-14). These
contributions include:

• Atmospheric corrections in remote sensing of terrestrial ecosystems
and biogeochemical processes during studies such as the International
Satellite Land Surface Climatology Program (ISLSCP), the
Hydrologic-Atmospheric Pilot Experiment in the Sahel (HAPEX-Sahel), and
the Boreal Ecosystem-Atmosphere Study (BOREAS) (Spanner et al., 1990;
Wrigley et al., 1992),

• Validation of aerosol data products from SAGE II, AVHRR, GOES Imager,
ATSR-2, and MODIS Airborne Simulator (Russell et al., 1986; Livingston
and Russell, 1989; Veefkind et al., 1999; Durkee et al., 1999; Tanre et
al., 1999),

• Studies of oil- and forest-fire smokes and cirrus clouds (Pueschel et
al., 1988; Pueschel and Livingston, 1990),

• Studies of radiative and chemical effects of tropospheric and
stratospheric aerosols (Bergstrom and Russell, 1999; Russell et al.,
1993a,b; 1996, 1999; Toon et al., 1993),

• Apportionment of aerosol optical depth to aerosol chemical
constituents (e.g., Hegg et al., 1997; Collins et al., 1999),

• Other closure studies to judge the mutual consistency of remote and in
situ aerosol measurements and the models that link them (e.g., Schmid et
al., 1999; Livingston et al., 1999; Redemann et al., 1999a; Russell and
Heintzenberg, 1999; Welton et al., 1999), and

• Intercomparisons of water vapor measurement techniques (e.g., Schmid
et al., 1999a,b; Livingston et al., 1999).

The proposed work will include tests of satellite retrieval algorithms
and studies of possible improvements by incorporating realistic models
of complex aerosols, water vapor and ozone effects that are based on
field campaign measurements with both in situ and remote sensors. When
appropriate, it will include generation of new, illustrative satellite
data products using improved algorithms. It will also include regional
and global model calculations of radiative effects of realistic
aerosols, water vapor, and ozone. These model calculations will be based
on integration of satellite, aircraft, and surface data, analogous to
our approach in previous studies (e.g., deriving North Atlantic regional
aerosol radiative effects by combining AVHRR midvisible optical depth
fields with intensive properties obtained from the sunphotometer and
other correlative data; Bergstrom and Russell, 1999). More broadly, they
will examine the relationship between atmospheric chemical change and
climate change, e.g., by integrating and intercomparing satellite and
other results from such experiments as SAFARI-2000 and ACE Asia. These
experiments are expected to provide many cases where airborne
sunphotometer measurements are coordinated with satellite overpasses
during biomass burning, continental plume transport over oceans, aerosol
physico-chemical evolution, and oceanic processes revealed by spaceborne
color measurements. The proposed research will perform innovative
analyses and improve aerosol optical models to combine the resultant
data sets in addressing the above questions.

2.  **BACKGROUND: PLANNED BIOGEOCHEMICAL FIELD CAMPAIGNS AND EXPECTED
    ROLES OF SATELLITE AND AIRBORNE SUNPHOTOMETER DATA PRODUCTS**

**2.1 SAFARI 2000**

**2.1.1 SAFARI 2000 Goals and Overall Approach.** The Southern African
Fire-Atmosphere Regional Science Initiative (SAFARI 2000) is an
international, interdisciplinary science initiative designed to increase
our understanding of the southern African ecological and climate system
as a whole, as well as its relationship to hemispheric and global
climate (Swap et al., 1998a,b; Swap and Annegarn, 1999). Its goal is to
understand the key linkages between the physical, chemical and
biological processes, including human impacts, essential to the southern
African biogeophysical system. Specific objectives of SAFARI 2000 are
to:

1\. Characterize and quantify the biogenic, pyrogenic and anthropogenic
aerosol and trace gas sources and sinks in southern Africa;

2\. Validate these observations using atmospheric transport and
chemistry models, ground-based, air-borne, and satellite-based
observations; and

3\. Determine the climatic, hydrological, and ecosystem consequences of
these biogeochemical processes.

SAFARI 2000 aims to exploit the unique environmental features of
southern Africa, which include a semi-closed atmospheric circulation
with clearly defined inflow and outflow regions, favorable to mass
balance ("budget-closing") experiments. This is especially so in austral
winter, when anticyclonic circulation and associated clear sky
conditions favoring satellite and airborne remote sensing dominate the
region on as many as 80% of days. Within this context strong emissions
of aerosols and trace gases from heavy industry and some of the world's
most extensive biomass burning combine to effect significant changes in
the biogeochemical cycling of the region, which includes significant
natural biogenic emissions of volatile organic carbon. Manifestations of
these processes include not only strong regional hazes but also
anomalously large concentrations of ozone in the middle and upper
troposphere over the south Atlantic.

SAFARI 2000 addresses a list of scientific questions (Swap et al.,
1998a,b; Swap and Annegarn, 1999). Those of greatest interest to this
proposal are:

• What are the sources, magnitudes, locations and temporal pattern of
aerosol and trace gas emissions into the atmosphere over Southern
Africa?

• What urban, industrial and transport activities within Southern Africa
are responsible for aerosol and trace gas emissions?

• What ecosystem processes are responsible for aerosol and trace gas
emissions?

• How do climate and other environmental conditions affect these
processes?

• What are the chemical properties of the aerosols emitted?

• How are aerosols and trace gases chemically transformed and
transported between the surface and the atmosphere and within the
southern African atmosphere?

• How do complex mixtures of gases and aerosols interact in a sunny, dry
environment, where they are often contained within narrow stable layers?

• How are these atmospheric constituents transported into and out of the
region, and what quantity is transported?

• How might changes in atmospheric aerosols and trace gas concentrations
affect the regional climate, biogeochemistry and land use of Southern
Africa?

• How do changes in ecosystem functioning and land-surface processes
affect emissions and thereby atmospheric chemistry and radiative forcing
of the southern African atmosphere?

To address these questions the SAFARI 2000 Science Plan (Swap and
Annegarn, 1999) specifies a suite of measurement and modelling
activities, organized into core elements. Of greatest interest to this
proposal are Core Elements 3-6 (Aerosols, Trace Gases, Clouds and
Radiation, and Modelling). These include ground-based, airborne, and
satellite measurements to characterize aerosol concentrations,
size-resolved composition (including secondary organic aerosols),
optical thickness, and direct and indirect radiative forcing; trace gas
composition, concentration, and optical and radiative properties; and
changes in regional radiative transfer. Modeling activities include
studies of ozone formation, modeling of aerosol physico-chemical-optical
properties (including size-resolved composition, optical thickness, and
scattering angular dependence), and modeling of radiative transfer. The
Modeling Core Element includes validation of satellite products.

SAFARI 2000 will be conducted over a three-year period, starting in
1999, with three intensive ground and flying field campaigns. This
proposal focuses on modeling and data analysis associated with the third
campaign, scheduled for August-September 2000, during the dry season.
This campaign will track the movement, transformations, and deposition
of dry-season emissions from biomass burning and other sources. Ground
measurements will include a relatively dense deployment of AERONET
sun/skyphotometers (Holben et al., 1998) plus core field site towers
supporting a variety of radiometers to measure surface albedo, among
other properties. Aircraft expected to participate include the NASA ER-2
for remote measurements, the University of Washington CV-580 for in-situ
measurements of clouds, aerosols, trace gases, and radiation, and two
Aero Commanders operated by African organizations.

**2.1.2. Satellite Data Products Relevant to SAFARI 2000 and this
Proposal.** The EOS Terra platform will carry the sensors MODIS, MISR,
MOPITT, ASTER, and CERES. As shown in Table 1, each of these is expected
to produce data products relevant to SAFARI 2000 and this proposal. For
example, MODIS and MISR will produce aerosol optical depth spectra that
will be used to study aerosol spatial distributions, transport,
evolution, and radiative forcing. MODIS will also produce column water
vapor and column ozone. ASTER's fine spatial resolution is expected to
help pinpoint fires and fine-scale land-cover change and use; however,
ASTER will rely on MODIS and MISR aerosol, water vapor, and ozone
products for atmospheric corrections. MOPITT is expected to help resolve
large-scale source, sink, and transport questions via its carbon
monoxide and methane measurements; however, possible impacts of strong
vertical gradients (i.e., stratified profiles) and dense smoke aerosols
on those products need to be investigated. CERES will produce data
products describing various radiances, albedos, and fluxes useful in
radiative forcing studies. TOMS sensors on several platforms (e.g.,
Earth Probes, and the new GLI on ADEOS II) will provide regional maps of
both column ozone and aerosol index. POLDER on ADEOS II will provide
aerosol measurements that benefit from its polarization sensing
capability. SeaWiFS and MODIS data products will include both ocean
color and aerosols in regions impacted by African continental outflow
over both the Atlantic and Indian Oceans, with and without coastal
stratus. All these satellite products will require validation over a
wide range of conditions. SAFARI 2000's suborbital measurements will
provide many opportunities for such validation. The suborbital
measurements will also be essential in extending data outside the
satellite overpass times and locations.

**2.1.3. Expected Role of Airborne Sunphotometry in SAFARI 2000.**
Planning documents for SAFARI 2000 have listed airborne sunphotometry as
a key measurement, and NASA Ames has requested funding to participate
with one or both of the Ames Airborne Tracking Sunphotometers (AATS-6
and/or AATS-14; see Appendix A and Russell, 1999). Furthermore, the
University of Washington is funded to install a port in its CV-580
(Section 2.1.1) to accommodate AATS-14, and Ames has held preliminary
discussions with South African scientists regarding flying AATS-6 on the
South African Aero Commander. However, budgets available within the NASA
Radiation Sciences Program and EOS instrument teams (e.g., MODIS) are
not adequate to cover the kinds of analyses described in this proposal.
Indeed, those budgets, if available, can probably cover only the costs
of (1) essential pre- and/or post-mission AATS calibrations and minor
instrument upgrades, and (2) acquiring AATS transmission data on SAFARI
flights and reducing a subset to aerosol/cloud optical depth spectra
(0.38-1.02 μm or 0.38-1.56 μm). With proper quality control and
ancillary SAFARI 2000 data, that AATS data set would provide the raw
material to address the science goals of this proposal when used in the
range of modeling, algorithm development, analysis, and validation
studies described in Section 3. Therefore, this proposal requests
funding from MDAR (EOS/IDS and/or ACMAP) for such studies. Here we
sketch the measurements and analyses possible, with examples from recent
studies using AATS-6 and --14 data.

Airborne sunphotometer measurements flown along transects near the land
or ocean surface in SAFARI 2000 can provide aerosol optical depth
spectra useful for validating products from simultaneous satellite
overflights. This is illustrated in Figure 1, which shows a comparison
of airborne sunphotometer (AATS-6), AVHRR, and ATSR-2 data acquired in
TARFOX over the Atlantic Ocean when the UW C-131A flew across a gradient
of aerosol optical depth between latitudes 37-39 N (Veefkind et al.,
1999). The flight path was chosen using half-hourly GOES images to
locate the aerosol gradient. Comparing Figures 1a and 1b shows that the
ATSR-2 retrieval reproduces the sunphotometer-measured optical depth
gradient better than the AVHRR retrieval. Comparing Figures 1c and 1d
shows how the ATSR-2 retrieval also matches the sunphotometer-determined
Angstrom exponent better than AVHRR.

Figure 2 shows other comparisons from TARFOX, when AATS-6 on the UW
C-131A underflew the MODIS Airborne Simulator (MAS) on the NASA ER-2
(Tanre et al., 1999). These comparisons focus on the wavelength
dependence of optical depth and illustrate how the magnitude of optical
depth affects the success of the MAS retrieval. Specifically, the good
agreement in wavelength dependence and magnitude obtained when optical
depth is relatively large (\>0.2 for λ\<1 μm) degrades when optical
depth decreases below \~0.05 (causing MAS-measured radiance from the
aerosol to decrease relative to that from the ocean surface).
Establishing such limits and uncertainties is a major reason for
validation studies. In SAFARI 2000 they could be conducted for a variety
of smoke and haze types and conditions, over different types of land
surfaces (e.g., densely vs. sparsely vegetated), the ocean, and on
transects spanning land and ocean.

Figure 3 illustrates how a change in aerosol type can affect the
validity of satellite retrievals. Specifically, Figure 3a shows the good
agreement between AVHRR and sunphotometer optical depths obtained
frequently in ACE 2 when the aerosol was confined to the marine boundary
layer; Figure 3b shows how this agreement degrades when an elevated
layer of Sahara dust is present. Possible reasons for this degradation
include differences between the wavelength-dependent single scattering
albedos and phase functions of the Sahara dust and those assumed in the
AVHRR retrieval (Durkee et al., 1999; Livingston et al., 1999; Schmid et
al., 1999), plus the height of the absorbing dust aerosols (e.g.,
Quijano et al., 1999). In Safari 2000, sunphotometer underflights of
different types of smoke and haze (e.g., biomass burning vs. industrial
emissions) could provide analogous tests of the validity of satellite
products as a function of aerosol type. Vertical profile flights by the
sunphotometer aircraft (e.g., the UW CV-580) would provide simultaneous
in situ data on aerosol physicochemical properties, helping to complete
the picture.

Figure 4 illustrates the ability of the airborne sunphotometers to
measure vertical profiles of multiwavelength aerosol optical depth and
extinction during such aircraft profiles. The case shown, obtained in
ACE 2, documents an elevated layer of Sahara dust (\~2-3.5 km asl)
overlying a very clean layer (\~1-2 km asl) and a moderately polluted
marine boundary layer (\<\~1 km asl). Note that the wavelength
dependence of extinction is very different in the marine and Sahara
layers, with extinction nearly independent of wavelength between 380 and
864 nm in the Sahara layer, owing to the relatively large particles
there. In SAFARI 2000 the strong atmospheric stratification associated
with the South African anticyclonic gyre is expected to cause many
occurrences of analogous layering, with different layers often having
different sources and characteristics. Airborne sunphotometry combined
with simultaneous in situ physicochemical-optical measurements will
provide a rich data set for modeling such diverse, vertically structured
aerosols and understanding their impact on satellite retrievals.

Closure studies that examine the degree of consistency between
sunphotometer measurements, in situ measurements, and the models that
link them are an important source of information on the strengths and
weaknesses of the examined measurement and modeling techniques. A
typical result from such a closure study is shown in Figure 5. The data
were obtained in ACE 2 when the Pelican aircraft ascended through a
marine boundary layer, carrying AATS-14 and a variety of in situ
samplers. The optical depth spectrum labeled "Caltech OPC" was obtained
by combining in situ size spectra with refractive index models obtained
from size-resolved chemical composition measurements at a nearby surface
site (which were consistent with size-integrated chemistry measured on
the aircraft). The optical depths labeled "Neph+PSAP" were obtained by
combining nephelometer measurements of aerosol light scattering (at 1 or
3 wavelengths) with absorption measurements from an absorption
photometer.

The result in Figure 5 is typical in that the optical depth spectrum
measured by sunphotometer (AATS-14) exceeds that calculated from the in
situ measurements. Although some of the error bars overlap (e.g., the
OPC-derived optical depth bars with the others), the fact that
sunphotometer-measured optical depths nearly always exceed in situ
derived optical depths in ACE 2, TARFOX, and other comparisons (e.g.,
Clarke et al., 1996; Hegg et al., 1997; Hartley et al. 1999; Kato et
al., 1999; Remer et al., 1997) points to a systematic phenomenon that
bears explaining. Possible reasons include (1) loss of semivolatile
aerosol material (e.g., organics) during in situ sampling that is not
accounted for in the in situ analyses (e.g., Eatough et al., 1996), and
(2) light absorption by a gas on the sunphotometer viewing path that is
not accounted for in the sunphotometer analyses (e.g., Halthore et al.,
1998). Explaining this persistent difference could have fundamental
implications for our understanding of aerosol properties and/or
radiative transfer. SAFARI 2000 should present excellent opportunities
for studying this question, especially on the UW CV-580, which will
carry enhanced instrumentation for measuring organic aerosols (e.g.,
Eatough et al., 1996) and spectral flux radiometers (Pilewskie et al.,
1998) that can help to distinguish aerosol absorption from gas
absorption.

Another type of closure study relating in situ and sunphotometer
measurements compares in situ size distributions with those retrieved
from sunphotometer optical depth spectra. Such a comparison is shown in
Figure 6. Within the optically effective diameter range (\~0.22 to 8 μm)
the AATS-14 retrieved distribution replicates the main features of the
in situ distribution, although for some diameters (\~0.7 to 3 μm) the
AATS-14 retrieved distribution exceeds the in situ values. This
exceedence is in accord with the systematic difference between
sunphotometer and in situ optical depth spectra noted above.

The size distribution retrieval in Figure 6 used a refractive index
model based on ACE 2 marine boundary layer aerosol chemistry, combined
with the constrained linear inversion program of King et al. (1978). In
the proposed research (Section 3) new aerosol optical models appropriate
to the South African aerosols will be developed and used both in the
King inversion procedure and in a new procedure based on the recent
results of Remer et al. (1998a) regarding persistent features of
multimodal aerosols (see Sections 3.1.1 and 3.1.4).

Water in both vapor and condensed phases has a strong influence on
radiative transfer and on aerosol size and composition. Given the strong
stratification present in the South African gyre, as well as the
horizontal contrast in water vapor sources among continental and marine
parts of airmass trajectories, one can expect important variations in
water vapor and associated aerosol changes in SAFARI 2000. The ability
of AATS-6 and AATS-14 to measure water vapor and aerosols simultaneously
on a common viewing path should be useful in this regard. This ability
is illustrated in Figure 7, which compares an AATS-14 water vapor
profile to simultaneous in situ measurements. Figure 8 shows a scatter
plot comparing AATS-6 water vapor columns with those obtained by
integrating radiosonde profiles in ACE 2. The rms difference, 0.10 g
cm^--2^ over a range of 1.5 to 3.3 g cm^--2^, is typical of other
comparisons we have made. For example, in the fall 1997 Water Vapor
Intensive Observation Period (IOP) of the Atmospheric Radiation
Measurement (ARM) program, AATS-6 water vapor column retrievals agreed
within 0.11 g cm^--2^ with results from the Global Positioning System (2
locations), 3 microwave radiometers, radiosondes, and two other
sunphotometers. The range of water vapor column amounts during the IOP
was 1 to 5 g cm^--2^.

SAFARI 2000 planning documents stress the importance of realtime or
quick-turnaround data analyses and open data access as means of
maximizing the scientific return from the measurements. Both AATS-6 and
AATS-14 have demonstrated this in previous campaigns like TARFOX and ACE
2, where they produced realtime color plots of aerosol optical depth
spectra that were used in flight direction and planning, as well as in
daily science team meetings (which included comparisons to satellite
products). With adequate preparation, this capability could be extended
in SAFARI 2000 to include realtime or quick-turnaround displays of water
vapor and ozone overburdens, as well as of the effective radius, volume,
and/or mass of the overlying aerosol column. The latter would be useful
for observing the evolution of aerosol size when, for example, following
a plume downwind, or for mapping cross-plume column masses. Acquiring
analogous plume-integrated sizes and masses with in situ sensors would
require time-consuming vertical profiling (thus reducing time available
for horizontal surveys) and would subject the aerosols to the sampling
challenges that are especially difficult on a vertically profiling
aircraft. Providing the above-described realtime displays requires the
development and testing of algorithms before the campaign, as described
in Sections 3.1.1-3.1.4.

SAFARI 2000 plans include an ER-2 lidar to measure vertical profiles of
aerosol backscatter, sometimes in coordination with vertical profile
flights by the UW CV-580. This will permit comparisons between AATS-14
extinction profiles (like those shown in Figure 4) and backscatter
and/or extinction profiles from the lidar. Both AATS-6 and AATS-14 have
participated in such comparisons previously. In ACE 2, for example,
Schmid et al. (1999) and Welton et al. (1999) compared lidar and
airborne sunphotometer profiles in a Sahara dust layer over the Izana
observatory in the Canary Islands. They got good agreement when the
lidar analysis used a backscatter-to-extinction ratio derived from
simultaneous ground-based sunphotometry. In TARFOX, Redemann et al.
(1999a) derived best-fit complex refractive indices in aerosol layers by
comparing simultaneous profiles of backscatter from an ER-2 lidar
profile with profiles of extinction and relative size distribution from
AATS-6 and optical particle counters on the UW C-131A. By combining the
best-fit complex refractive indices with the relative size distribution
profiles, Redemann et al. (1999b) then produced profiles of aerosol
single scattering albedo (SSA). Figure 9 shows an example result,
compared to the SSA profile obtained by Hartley et al. (1999) using
simultaneous measurements of aerosol scattering, absorption, and
scattering humidification factor.

Combining airborne sunphotometer optical depth profiles with radiative
flux profiles is a potentially powerful way to determine the absorption
properties (hence SSA) of the ambient aerosol, unperturbed by sampling
processes. This is illustrated by the TARFOX results shown Figure 10
(Russell et al., 1999b). The data points show the aerosol-induced
decrease in downwelling solar flux measured by pyranometers on the UK
C-130 during two descents into aerosol layers over the Atlantic Ocean,
plotted versus broadband aerosol optical depth derived from occulted
pyranometer measurements. (The absorbing gas and Rayleigh components
have been removed from both the flux change and the optical depth using,
e.g., concurrent water vapor measurements.) The curves show calculations
of the expected flux change, based on aerosol size distributions
retrieved from AATS-6 sunphotometer measurements on the UW C-131A, a
real refractive index spectrum for aqueous sulfate, and a range of
imaginary refractive indices giving the midvisible single-scattering
albedos ω(550 nm) shown. Comparing the data points and curves shows that
the best-fit value of ω(550 nm) is \~0.9; chi-square analyses using the
error bars on the pyranometer optical depths and flux changes (the cross
in Figure 10) yield ω(550 nm)=0.895±0.025 and 0.905±0.045 for July 25
and 27, respectively.

In SAFARI 2000 the UW CV-580 will be carrying Solar Spectral Flux
Radiometers (SSFR, Pilewskie et al., 1998), which, together with the
AATS-14 optical depth measurements (380-1558 nm), will permit much
improved flux change studies. The spectral resolution of SSFR and
AATS-14 will permit the type of flux change analysis shown in Figure 10
to be accomplished in a wide range of narrow (5 nm) spectral bands. This
will permit, for example, solving for SSA as a function of wavelength.
It will also aid in identifying absorption features that might be due to
unknown gas spectroscopy, rather than aerosols. And it will help to
identify artifacts that might be caused by cloud fragments or surface
albedo effects. The measurements in Figure 10 were made over the ocean
during a cloud-free period to minimize such effects. This will be done
in SAFARI 2000 also; however, the fine spectral resolution in the SSFR
flux measurements may allow the measurements to be extended over a
uniform land surface, and may also allow some relaxation in the
cloud-free criterion. This will be investigated. These types of
measurements will also be carried out when an absorbing aerosol is
carried over a uniform stratus deck; the underlying cloud reflectivity
maximizes aerosol absorption in such a case. Biomass smoke outflow over
Namibian coastal stratus in SAFARI 2000 could provide such an
opportunity.

Figure 11 shows a final example of how our sunphotometer data have been
combined with satellite data to estimate regional aerosol effects on
radiation budgets, as could also be done in SAFARI 2000. The
aerosol-induced flux changes shown in Figures 11a-e and 11g were
obtained by combining seasonal maps of midvisible aerosol optical depth
from AVHRR/NOAA (Husar et al., 1997) with aerosol intensive properties
determined in TARFOX (specifically, a relative size distribution derived
from a typical AATS-6 optical depth spectrum, an aqueous sulfate real
refractive index (\~1.38 at 550 nm) and an imaginary refractive index
(-0.01) that yielded the best-fit single-scattering albedo of 0.9 in
Figure 10). In Figures 11f and 11h a nonabsorbing aerosol is assumed, to
show the sensitivity of the results to single scattering albedo. In
SAFARI 2000 analogous estimates of regional radiative flux changes could
be calculated, but with considerably improved capabilities. MODIS, MISR,
and POLDER optical depths, plus the TOMS aerosol index, should all be
available over land (unlike the AVHRR optical depths which are
restricted to the oceans). And improved information on
wavelength-dependent aerosol absorption should be available from the
combination of spectral fluxes and optical depths (SSFR and AATS-14) on
the UW CV-580 mentioned above (not to mention potential improvements in
the in situ measurements).

**2.2 African Dust Plume and Water-Leaving Radiance Opportunities on
SAFARI 2000 Transits**

Transit flights by the UW CV-580 from the US to Africa and back before
and after the August-September 2000 SAFARI campaign can provide valuable
opportunities for measuring the Sahara dust plume and studying its
effect on satellite-derived water-leaving radiance, as well as its
relationship to TOMS aerosol and ozone products. A stopover in the Cape
Verde Islands (\~16 N, 22 W), currently planned by UW, would provide an
excellent base for such measurements, since the islands are near the
location of maximum dust optical depth in the August-September season.
Plume underflights across the gradient (cf. Figure 1), from maximum to
minimum optical depth, would provide a test of satellite
atmospheric-correction algorithms over a wide range of difficulty.
Vertical profiles through the layer (cf. Figure 4) would show the
relative altitudes of attenuation by aerosols, Rayleigh, water vapor,
and ozone. Flights within the elevated dust layer would provide
important in situ measurements for closure studies (cf. Figures 5 and 6)
and detailed characterization of the dust aerosols.

**2.3 ACE Asia Survey and Evolution Component (AA-SEC)**

**2.3.1 ACE Asia Goals and Overall Approach.** The Asian Pacific
Regional Aerosol Characterization Experiment (ACE Asia) is the fourth in
a series of aerosol characterization experiments organized by the
International Global Atmospheric Chemistry Program (IGAC). Each ACE is
designed to integrate suborbital and satellite measurements and models
so as to reduce the uncertainty in calculations of the climate forcing
due to aerosol particles (Huebert et al., 1999). ACE Asia focuses on
aerosol outflow from Asia to the Pacific basin because (1) Asian
anthropogenic emissions and mineral dust are very different from the
environments of previous ACE experiments, and (2) Expected increases in
Asian emissions have the potential to cause large changes in radiation
budgets, cloud microphysics, and hydrological output over the coming
decades.

The goals of ACE-Asia are to determine and understand the properties and
controlling factors of the aerosol in the anthropogenically modified
atmosphere of Eastern Asia and the Northwest Pacific and to assess their
relevance for radiative forcing of climate (Huebert et al., 1999).
Subsidiary objectives are to:

1\. Determine the physical, chemical, and optical properties of the
major aerosol types in the Asian Pacific region, determine their state
of mixing, and investigate the relationships among these properties.

2\. Quantify the physical and chemical processes controlling the
evolution of aerosols in the Asian Pacific region and in particular
their physical, chemical, and optical properties.

3\. Evaluate numerical models which will extrapolate aerosol properties
and processes from local to regional and hemispheric scales, and assess
the regional direct and indirect radiative forcing by aerosols in the
Asian Pacific region.

ACE Asia will include a network of ground stations operated over the
2000-2004 timeframe, with intensive, multiplatform field studies to
focus on specific objectives. The Survey and Evolution Component
(AA-SEC) is the first of the ACE Asia intensive field studies, and the
only one for which a written proposal (Huebert et al., 1999) has been
developed. Planned for March-April 2001, AA-SEC is designed to answer a
series of questions, which can be grouped as follows (Huebert et al.,
1999):

[Aerosol Survey]{.underline} (What are the vertical and regional
distributions of aerosol concentrations and properties under various
meteorological conditions?)

A. What are the relative size-dependent contributions of sulfate,
nitrate, carbonaceous material, sea salt, primary anthropogenic
particles, and dust to the optical properties (absorption, total and
angular scattering) of aerosols?

B. How do the interactions between these species (their state of mixing)
affect their optical properties?

C. How are the distributions affected by specific meteorological events?

######## Aerosol Evolution (How do aerosol properties evolve as they move offshore?) 

D. How do aerosol properties and process rates evolve with time
(distance) over the ocean?

E. What are the lifetimes or removal rates of particles?

F. What is the rate of exchange of particles and precursor gases between
the free troposphere, buffer layer, and boundary layer?

[Aerosol Interactions with Gas-Phase Atmospheric Chemistry]{.underline}
(What role does the atmospheric chemistry of the Asian-Pacific region
play in influencing aerosol properties and evolution, and likewise, how
does the Asian aerosol affect tropospheric chemistry in the region?)

G. How does mineral dust interact with atmospheric gas-phase chemistry?

H. How does sea salt interact with gas-phase chemistry?

I. How does the anthropogenic/urban aerosol interact with gas-phase
chemistry?

The AA-SEC omnibus proposal to NSF (Huebert et al., 1999) describes a
plan to address these questions using three US mobile platforms (the
NCAR C-130, the CIRPAS Twin Otter, and a NOAA or UNOLS ship) and 1-2
enhanced ground stations working in coordination with ships, aircraft,
lidars, and surface sites from a variety of nations (e.g., Japan, Korea,
China, and Taiwan). The operations base will probably be located in
southern Japan. Satellites will be used both for experimental planning
(such as locating dust layers) and for extrapolating results over larger
scales. AA-SEC will survey concentrations and properties vs. altitude
and location, and it will conduct Lagrangian experiments, in which
repeated flights are made into a tagged airmass for 1-2 days, to improve
process models, identify reaction pathways, and quantify rates. Efforts
will be made to coordinate some AA-SEC flights with the NASA TRACE-P
program, which will be focusing on photochemistry in Asian outflow at
about the same time, using measurements on the NASA DC-8 and P-3. If
possible AA-SEC will coordinate some observations with an airborne
simulator for the PICASSO-CENA spaceborne lidar.

**2.3.2 Satellite Data Products Relevant to AA-SEC.** As in previous
ACEs, satellite data products will be used both in realtime to plan and
direct flights and for post-campaign analyses. For example, in AA-SEC
flights to study the plumes of desert dust emanating from Asia,
satellite observations will be used to identify locations of maximum
dust concentrations and areas where concentration gradients can most
easily be studied. In Lagrangian experiments that study aerosol
evolution, satellite observations of the decay of backscatter by the
continental plume will be used to identify regions where removal
mechanisms seem especially effective. As in SAFARI 2000, the
availability of MODIS, MISR, and MOPITT on EOS Terra will provide new
capabilities that will help address the goals of AA-SEC (e.g., Table 1);
at the same time, AA-SEC will provide new conditions and data sets with
which to validate Terra and other satellite data products. As an example
of the latter, the yellowish soil dust aerosol layers emanating from
Asia are known to have different spectral absorption characteristics
than the red-brown Sahara dust; however, these differences are not well
quantified. AA-SEC measurements during yellow dust plume events should
provide important new validation data sets for TOMS aerosol and ozone
products, and for water-leaving radiance products from SeaWiFS as well
as MODIS. Many of the other validation opportunities provided by AA-SEC
are analogous to those described in Section 2.1.2 for SAFARI-2000
(albeit with different aerosols); for brevity the reader is referred to
Section 2.12.

**2.3.3 Expected Role of Airborne Sunphotometry in AA-SEC.** The AA-SEC
Science and Implementation Plan (Huebert et al., 1999) specifies aerosol
optical depth measurements as part of the minimum requirement for both
surface and airborne platforms, and it includes an Ames tracking
sunphotometer as part of the "Highest Priority -- Essential" payload for
the NCAR C-130 and part of the recommended payload for the Twin Otter.
Some of the reasons for these inclusions are summarized below. However,
it is important to note that the one budget identified so far for
possible support of the AA-SEC airborne sunphotometer measurements (the
NOAA Global Aerosols Program) is inadequate to support the type of
interdisciplinary, integrated analyses described in Section 3 of this
proposal. The NOAA budget, if obtained, would probably cover only the
costs of (1) essential pre- and/or post-mission AATS calibrations and
upgrades, and (2) acquiring data on AA-SEC flights and reducing a subset
to aerosol/cloud optical depth spectra. The Ames sunphotometer team is
ineligible for NSF funding. Therefore, this proposal requests MDAR
funding for the integrated modeling and analyses described in Section 3,
based on the following expected role of airborne sunphotometry in
AA-SEC.

The AA-SEC Science and Implementation Plan (Huebert et al., 1999)
includes a variety of schematic C-130 and Twin Otter fight plans, each
designed to address specific questions from the list above. For example,
they include flights at several altitudes across the edges of elevated
dust layers and upwind and downwind of urban-industrial plumes. Some
flight patterns include legs with the Twin Otter flying near the surface
under a plume while the C-130 overflies the plume with a
downward-looking lidar. When such a leg spans the gradient from plume
core to edge during a satellite overpass, AATS optical depth spectra
measured from the Twin Otter would provide validation data for
comparisons such as those in Figures 1-3. At the same time the AATS data
could provide a test of the backscatter-to-extinction ratios and other
assumptions used to derive optical depths from the C-130 lidar. Such
comparisons could be a valuable precursor to validation flights for
PICASSO-CENA conducted after its launch (scheduled for 2003). AA-SEC
flight plans also call for the Twin Otter to ascend from near the
surface through the aerosol layers aloft while collecting in situ data
on aerosol size distribution, chemistry, light scattering and
absorption. This would yield AATS vertical profiles of multiwavelength
extinction (as in Figure 4) for comparison to lidar profiles (as was
done, e.g., in ACE 2 by Schmid et al., 1999; and Welton et al., 1999).
It would also yield the in situ measurements needed for closure studies,
such as those illustrated by the ACE 2 results in Figure 5. Comparisons
of the profiles of sunphotometer extinction, lidar backscatter, and in
situ size distribution can yield best-fit values of complex refractive
index and single-scattering albedo for each sampled layer, as
demonstrated by Redemann et al. (1998, 1999a,b) with PEM-West and TARFOX
measurements. These values could be compared to single scattering
albedos from the in situ scattering and absorption measurements (e.g.,
Figure 10) and to complex refractive indices from the in situ chemistry
measurements, taking into account the local humidity and effects of
aerosol hygroscopicity.

Sunphotometer-derived column or layer size distributions could be
validated by comparisons to in situ data from profile flights (as, e.g.,
in Figure 6), and used when underflying plumes to document changes in
overlying aerosol effective radius, surface area, and mass. This
information should be valuable in aerosol evolution studies (e.g., to
see whether sedimentation modifies the dust size-distribution in a
predictable way) and reduce the need for aircraft profiles, which take
flight time away from horizontal legs. However, deriving accurate
information on aerosol size, surface area, and mass from sunphotometer
optical depth spectra requires algorithms that incorporate
size-dependent effective refractive indices that are appropriate to the
aerosol on the sunphotometer viewing path. Development of such
algorithms is discussed in Section 3. Incorporation of simultaneous AATS
data on water vapor will be investigated as a means of accounting for
possible humidification effects on refractive index (which will be
different in sulfate layers and dust layers, for example).

**2.4 Other Possible Experiments**

In addition to SAFARI 2000, its transit flights, and ACE Asia, there are
other experiments being considered or planned for CY 2000 and 2001 in
which our airborne sunphotometers may participate. If this occurs, the
resulting data sets would be made available to the modeling and data
analysis studies proposed here. An example of such a study is the
Florida/Caribbean Dust study being considered for Summer 2000. This
joint Navy/NASA study would investigate the African dust carried over
the Caribbean and Florida by using a combination of aircraft, satellite
and surface measurements. We have been approached about the possibility
of participating with AATS-6 or AATS-14 on the Navajo aircraft and are
interested; however, these measurements are not yet funded. Another
possibility is operating AATS-6 or AATS-14 on the NASA P-3 during the
TRACE-P study of the impact of Asian emissions on atmospheric chemistry
in the Pacific Basin. TRACE-P is planned for March and April 2001 and
would thus coincide, and possibly coordinate with ACE Asia SEC. We are
considering proposing to operate AATS-6 or AATS-14 on the P-3 in
TRACE-P, to provide satellite validation data and enhance aerosol
chemical-physical-optical closure studies and trace gas photochemical
studies. However, our decision to propose will depend on the experiment
definition in the TRACE-P NRA, the potential collaborations with other
TRACE-P scientists, and available budgets.

3.  **PROPOSED RESEARCH**

**3.1 Year One**

**3.1.1 Task 1.1: Optical Modeling of Smokes and Other Aerosols Expected
in SAFARI 2000.** The objective of this task is to produce models that
reflect the size-dependent chemical composition and mixing state of the
various SAFARI 2000 aerosols (e.g., biomass smokes, industrial and
biogenic aerosols) and can be used to forward-calculate single-particle
extinction kernels and extinction spectra for specified size
distributions. Such models are needed by algorithms that retrieve size
distributions and other properties from sunphotometer extinction or
optical depth spectra (see Task 1.4 below). When extended to calculate
scattering phase functions, they can also be used in algorithms that
retrieve optical depth from satellite-measured radiances and in
calculations of aerosol-induced radiative flux changes. In TARFOX
relatively simple models were developed for this purpose, assuming
size-independent homogeneous internal mixtures of sulfate, organics,
black carbon, and water (Hignett et al., 1999) or just sulfate, black
carbon and water (Russell et al., 1999b). In ACE 2 ground-based
measurements of size-resolved chemical composition (including three
forms of sulfate, organic and elemental carbon, sea salt, water, and
soil dust) were used to develop models of boundary-layer and dust-layer
aerosols that used a combination of internal and external mixing, all
assuming homogeneous spheres (Collins et al., 1999). Recently our group
has begun using shell-and-core calculations to model black carbon
inclusions in sulfate aerosols (Redemann et al., 1999c), including the
effect of hygroscopic growth on light absorption and single scattering
albedo. In this task we will extend our previous models to include
biomass smoke aerosols and others expected and/or found in the SAFARI
2000 area. Information on biomass smoke aerosols will be obtained from
published results on Brazilian biomass smokes measured in SCAR-B (e.g.,
Dubovik et al., 1998; Kaufman et al., 1998; Martins et al., 1998; Remer
et al., 1996, 1998b; Reid et al., 1998a,b,c; Yamosoe et al., 1998), on
African savanna smokes measured in SAFARI 92 (e.g., Andreae et al.,
1998; Le Canut et al., 1996) and on both measured in TRACE-A (e.g.,
Anderson et al., 1996). This will include the shell-and-core and
discrete diploe approximation results of Martins et al. (1998) used to
represent soot inclusions and packed soot clusters.

**3.1.2 Task 1.2: Ozone-Aerosol Separation Algorithm Refinement and
Simulations.** The objective of this task is to optimize the AATS-14
ozone retrieval algorithm for the aerosol and ozone conditions expected
in SAFARI 2000 and to simulate its performance under those conditions.
Our current operational AATS-14 ozone algorithm uses the Chappuis-band
quadratic fitting technique described by King and Byrne (1976) and
previously applied by one of us (B. Schmid) to the University of Bern
18-Channel Tracking Sunphotometer, as well as by Michalsky et al. (1995)
to rotating shadowband radiometer measurements. We use this
ozone-aerosol separation algorithm primarily to improve the accuracy of
aerosol optical depth spectra in the Chappuis-band region (\~500-750 nm;
cf. Figure 12) when ancillary data on ozone column contents (e.g., from
TOMS) are not available. However, in the proposed research it may prove
useful to compare the TOMS aerosol index (obtained from measurements at
340-380 nm) and TOMS column ozone (obtained from the Hartley-Huggins
band, \~300-340 nm) to independently derived AATS-14 aerosol optical
depth spectra (380-1558 nm, Figure 12) and column ozone (from
Chappuis-band absorption). Also, when enhanced tropospheric ozone layers
are present above strong aerosol layers in SAFARI 2000 (as observed,
e.g., in TRACE-A by Browell et al., 1996), sunphotometer ozone column
retrievals obtained while flying transects above most aerosol optical
depth but below the tropospheric ozone peak may be able to reveal
tropospheric ozone spatial structure that has finer horizontal scale
than the overlying stratospheric ozone. This may prove useful since
current SAFARI 2000 plans do not include an airborne ozone lidar.
Therefore, in this task we will investigate possible refinements to our
AATS-14 ozone retrieval algorithm, and we will simulate its performance
with aerosol and ozone horizontal and vertical structures expected in
SAFARI 2000, based on ozone and aerosol results from SAFARI 92 and TRACE
A (e.g., Anderson et al., 1996; Browell et al., 1996; Chatfield et al.,
1996)

One possible refinement we will investigate is use of a SAGE III-like
least squares technique (Russell et al., 1996; Cunnold et al., 1996) for
ozone-aerosol separation. We recently compared our current algorithm to
a SAGE III-like algorithm as part of our SAGE III Science Team research.
The comparison used tropospheric data sets acquired with AATS-14 in the
ACE-2 field campaign (Schmid et al., 1999). The algorithms were compared
for a range of aerosol optical depths (0.008 \< τ~a~(500 nm) \< 0.4),
sampled by flying AATS-14 at altitudes from sea level to 3.6 km. Ozone
column amounts were about 300 Dobson Units (DU), which produced an ozone
optical depth of about 0.04 at the Chappuis peak near 600 nm. The
least-squares technique uses a matrix-inversion structure like that used
for SAGE II \[i.e., Eqs. (17)-(19) of Chu et al. (1989)\] and SAGE III
\[Eqs. (3.2.2.6)-(3.2.2.8) of Russell et al. (1996)\], with
transmissions measured at AATS-14 wavelengths 380, 453, 500, 525, 605,
667, 779, 864, and 1558 nm (cf. Figure 12). Results to date show that
the two algorithms produce ozone values that agree within about 5 DU for
τ~a~(500) \< 0.01 and within 10 DU for 0.01 \<τ~a~(500) \< to 0.07.
However, differences can approach or exceed 100 DU when τ~a~(500) \>
0.3.

Steele and Turco (1997) and Cox (1998) have shown that the accuracy of
ozone-aerosol separation via least-squares techniques can be sensitive
to the coefficients used to express aerosol extinction at an
ozone-sensitive wavelength (e.g., 600 nm) in terms of aerosol extinction
at ozone-insensitive or less-sensitive wavelengths (e.g., 1020 and 453
nm). They show how different choices of these coefficients are more or
less appropriate depending on the typical range of aerosol size
distributions present during the measurements (e.g., they consider a
wide range of prevolcanic and postvolcanic stratospheric sulfate
aerosols). However, it is also important to consider the sensitivity of
derived ozone and aerosol products to measurement error. This
sensitivity is also dependent on the choice of the above coefficients.
Thus the choice of the "best" coefficients must carefully consider both
typical measurement errors at each wavelength and the typical range of
aerosol characteristics (e.g., size distributions and compositions)
likely to be encountered. This range is considerably wider in the
troposphere than in the stratosphere. Therefore in this task we will use
the tropospheric data sets from ACE 2, SCAR-B, SAFARI 92, and TRACE-A
mentioned above, plus the aerosol optical models developed in Task 1.1,
to investigate the best forms of least-squares techniques for separating
ozone and aerosols in AATS-14 data sets.

A primary determinant of the accuracy of ozone-aerosol separation in the
vicinity of 600 nm is the relative size of ozone and aerosol
line-of-sight optical depths there. For example, a typical stratospheric
ozone optical depth at 600 nm is only \~0.05 (cf. Figure 12). Hence,
when midvisible aerosol optical depths exceed about 0.2, retrieved ozone
amounts become very sensitive to aerosol extinction estimated at 600 nm
from other wavelengths; consequently, the retrieved ozone amounts have
large uncertainties. These uncertainties can be markedly reduced by
flying the sunphotometer to higher altitudes, where aerosol optical
depth is less. The usefulness of this approach in SAFARI 2000 for
getting information on tropospheric ozone columns will depend on whether
there is significant tropospheric ozone above the strong aerosol layers.
Therefore, in this task we will use ozone and aerosol results from
SAFARI 92 and TRACE A (e.g., Anderson et al., 1996; Browell et al.,
1996) as inputs to simulations of AATS-14 ozone retrievals in vertical
profiles from the surface to the top of the tropospheric aerosol layers.
The results of Browell et al. (1996) showing that sometimes there are
large tropospheric ozone concentrations above the tropospheric aerosols
is encouraging. Nevertheless, the simulations may show that the
frequency of occurrence of such conditions will not often lead to
successful Chappuis-band retrievals of tropospheric ozone features with
AATS-14 in SAFARI 2000. In this case we will also look at the
desirability and feasibility of replacing some of the aerosol channels
in AATS-14 with channels in the Hartley-Huggins ozone band.

**3.1.3 Task 1.3: Water Vapor Retrieval Refinement.** Schmid *et al.*
(1996) reported a comparison of modeling (using LOWTRAN7, MODTRAN3,
FACSODE3P and the Thomason (1985) Model) and empirical approaches to
retrieve columnar water vapor from ground-based sunphotometers. More
recently, Halthore et al. (1997) emphasized the improved performance
achievable by using a bandwidth of 10 nm or less for the 940-nm filter
and by using MODTRAN3 for water vapor absorption calculations. And very
recently, Giver et al. (1999) reported errors in the HITRAN data base
(used by MODTRAN) for certain lines in the 940-nm band (cf. Figure 12),
showing that the HITRAN line strengths are 14.4% too small. If this
error applies to all lines in the 940-nm band, water vapor columns
retrieved from measured band transmittances would be about 14% too
large. As noted in Section 2.1.2, previous comparisons of our AATS-6 and
AATS-14 water vapor retrievals (which use MODTRAN 3.5 v 1.1) to results
from radiosondes, airborne in situ measurements, Global Positioning
System retrievals, microwave radiometers, and other sunphotometers under
a wide range of water vapor columns (1 to 5 g cm^--2^) have yielded
typical agreement within 0.1 g cm^--2^ (cf. Figures 7 and 8), which
suggests that any systematic bias in our retrievals caused by erroneous
line strengths is less than 14%. Nevertheless, the fact that AATS
retrievals in the Fall 1997 Water Vapor Intensive Observation Period
(IOP) were "wetter" than the average suggests that we perform a review
of the latest spectroscopy available for the 940-nm band and make any
necessary revisions to our AATS water vapor retrieval algorithm. We will
do so in this task.

**3.1.4 Task 1.4: Aerosol Column Size Distribution and Mass Retrieval
Algorithm Development.** The objective of this task is to produce
algorithms, tailored to the aerosols expected in SAFARI 2000, that
retrieve aerosol column size distribution, effective radius, surface
area, volume, and mass from AATS-6 and AATS-14 optical depth or
extinction spectra (380-1020 nm and 380-1558 nm). An example of a size
distribution retrieved from an AATS-14 extinction spectrum has been
shown in Figure 6 (Section 2.1.3). That retrieval used the constrained
linear inversion program of King et al. (1978) and assumed internally
mixed homogeneous spherical aerosols with a complex refractive index
consistent with the chemical composition of the polluted marine boundary
layer in the ACE 2 area. An advantage of the King et al. technique is
that it makes no assumption about the mathematical form of the retrieved
size distribution. However, it usually requires some human intervention
in judging the best radius limits, smoothing parameter values, and
iteration-averaging procedures, each of which is influenced by the
nature of the aerosol extinction spectrum being inverted. Hence, it is
not well suited to automated inversion of large volumes of data.

Recently, as part of TARFOX and ACE 2 analyses supported by NASA's
Global Aerosol Climatology Program (GACP), we developed a retrieval
algorithm that is better suited to automated inversions and that can
also accommodate aerosols with size-dependent chemical composition and,
with some restrictions, shell-and-core structures and external or
internal mixtures. The technique is based on the findings of Remer and
Kaufman (1998) that their very large set of Sun/sky radiometer
measurements in the US Eastern seaboard for a wide range of aerosol
optical depths (0.05 to 0.60 at 670 nm) can be well represented by a
linear combination of 5 lognormal modes, each with a fixed width and
central radius value. Moreover, two of the modes, identified as coarse
and stratospheric (Pinatubo volcanic), also had fixed amplitude
(particle number or volume). Thus, the variability of the best-fit size
distribution model resulted entirely from variations in the amplitude of
the remaining three modes (called accumulation-1, accumulation-2, and
salt). Our new retrieval algorithm assumes the 5 Remer/Kaufman modes
(with the stratospheric mode currently set to zero) and varies the
amplitude of the 3 variable modes to obtain a best fit to our measured
AATS-6 and AATS-14 optical depth and extinction spectra from TARFOX and
ACE 2. Because the algorithm uses a precomputed extinction spectrum for
each mode (assuming intensive optical properties from TARFOX and/or ACE
2), best-fit solutions are obtained in a single step via linear least
squares, with no need for iteration or human intervention. It is thus
fast and lends itself well to automated retrievals for large volumes of
data. To date it has provided a good fit to all TARFOX or ACE 2 optical
depth spectra tried.

Remer et al. (1996; 1998) have found analogous regularities in the
multimodal size distributions retrieved from their Sun/sky measurements
of biomass burning aerosol during SCAR-B in Brazil. Their dynamic
aerosol model, which is based on the combined regularities found in
Brazil and Eastern US aerosols, is now used in the spaceborne MODIS
algorithm to retrieve aerosol properties over land (Kaufman et al.,
1997b; King et al., 1999). In this task we will extend our multimodal
retrieval algorithm to include biomass burning aerosols and others
expected in SAFARI 2000. The work will use the smoke size modes found by
Remer et al. (1996; 1998) for Brazil biomass smokes and will also look
at results from SAFARI 92 (cf. Task 1.1) for possible differences in
African smokes and other South African aerosols. Extinction spectra for
each mode will be precalculated for a variety of size-dependent chemical
compositions based on the SCAR-B and SAFARI 92 results, using refractive
indices, shell-and-core structures, and discrete dipole approximation
results from Task 1.1. The resulting algorithms will be built into the
AATS-6 and/or AATS-14 data acquisition computers before the SAFARI 2000
deployment so that results can be displayed in realtime during flights
or made available for postflight Science Team meetings. This task will
also assess the potential value to size distribution retrievals of
extending AATS-14's longest wavelength from 1558 nm to about 2200 nm,
especially for the soil dust aerosols to be probed on SAFARI 2000
transit flights and in ACE Asia.

**3.1.5 Task 1.5: Quick-Look Analyses and Comparisons to Satellite
Data.** This task will use the algorithms developed in Tasks 1.2-1.4 to
display in realtime during the SAFARI 2000 deployment (August-September
2000) the aerosol column size distribution, effective radius, surface
area, volume, and mass, plus water vapor and ozone column amounts,
retrieved from AATS-6 and/or AATS-14 optical depth and transmission
spectra. The optical depth spectra and retrieved products will be made
available in flight and during field Science Team meetings for flight
planning and direction. They will also be used for quick-look
comparisons to whatever satellite data products are available in the
field. In past experiments these have included aerosol optical depths
from AVHRR on NOAA 14, Imager on GOES, and a radiometer on Meteosat. Any
analogous quick-look products from EOS Terra MODIS and MISR (including
atmospheric corrections for ocean color and land products), plus TOMS
aerosol index and ozone, will be compared to the sunphotometer products
in the field.

**3.1.6 Task 1.6: Preliminary Aerosol Radiative Effect Calculations.**
The goal of this task is to prepare for calculating radiative effects of
SAFARI 2000 aerosols over Africa and surrounding oceans by making
preliminary calculations that combine pre-SAFARI 2000 satellite data
(e.g., 1996-7 results from OCTS and POLDER on ADEOS, or TOMS aerosol
indices) with results from the mixed aerosol optical models developed in
Task 1.1. Our group has extensive experience in the application of
radiative transfer models to the calculation of aerosol-induced
radiative flux changes. For example, *Bergstrom and Russell* \[1999\]
used a generalized two-stream model to derive North Atlantic regional
aerosol radiative effects (by combining AVHRR midvisible optical depth
fields with intensive aerosol optical properties---see Figure 11), while
*Redemann et al.* \[1999a\] used the Fu-Liou broadband radiative
transfer model \[*Fu and Liou*, 1992; *Fu and Liou*, 1993\] to
investigate the vertical structure of the direct shortwave aerosol
radiative forcing. Similar approaches will be used in this task.

**3.2 Years Two and Three**

**3.2.1 Task 2.1: Satellite Validation Studies.** Extensive comparisons
of the type shown in Figures 1-3 will be made between satellite data
products and airborne sunphotometer aerosol optical depth spectra,
wavelength dependence parameters (e.g., the Angstrom exponent), and
water vapor and ozone column contents. Satellite data expected to be
available for this purpose are listed in Table 1. Efforts will focus
first on the SAFARI 2000 data set (including data from Sahara dust
measurements on transits) and later on the ACE-Asia data set. The degree
of agreement or disagreement found will be quantified in terms of
root-mean-square differences and mean biases, all as functions of
wavelength, aerosol type, and viewing condition (including surface type
and solar and satellite angles). The airborne sunphotometer data will be
used to assess the degree of variability within satellite pixels
(including variations between AERONET and other ground sunphotometer
sites), which may be particularly important near localized sources like
small biomass fires or for measurements in broken cloud fields. Aerosol
models assumed in the satellite retrievals will be compared to the
aerosol models developed in Tasks 1.1 and 2.2, and also to aerosol
properties determined from in situ measurements in each campaign. Where
significant differences in assumed and actual aerosol properties are
found, examples of adjusted satellite products will be produced, using
the single scattering albedo and phase function of the actual aerosols.
Possible shape effects for soil dust and sea salt aerosols will be
investigated (e.g., Mishchenko et al., 1997; Kahn et al., 1997), as well
as effects of the vertical distribution of absorbing and nonabsorbing
aerosols (e.g., Clark et al., 1997; Quijano et al., 1999). Implications
of these studies will be investigated not only for atmospheric products
(e.g., aerosols, water vapor, and ozone), but also for ocean color and
land surface products as affected by atmospheric corrections.

**3.2.2 Task 2.2: Update of Aerosol Optical Models, Including Mineral
Dusts.** The aerosol optical models developed in Task 1.1 will be
updated using the suborbital measurements (e.g., airborne sunphotometer,
ground Sun/sky radiometer, air and ground lidar, and in situ chemical,
physical and optical) made in SAFARI 2000 and ACE Asia. Areas of
emphasis will include quantifying characteristic differences between the
African (reddish-brown) and Asian (yellowish) soil dust aerosols (e.g.,
Sokolik and Toon, 1999; Sokolik, 1999) and capturing changes that occur
during downwind evolution of various aerosols (including dusts and
smokes) as a result of agglomeration of different particles (e.g., soot,
sulfates, nitrates), condensation of water and/or organic vapors, and
photochemical reactions outside and inside of clouds. Particular
emphasis will be placed on quantifying the wavelength- and
humidity-dependent single scattering albedo of realistic multicomponent
aerosols, since this parameter is so important in determining aerosol
radiative impacts on climate (including top-of-atmosphere forcing,
surface forcing, stability changes, and cloud changes). Effects of shape
on scattering phase functions will also be investigated, including
characteristic shape changes that occur during downwind evolution.

**3.2.3 Task 2.3: Aerosol Evolution and Budget Studies.** We will
combine the algorithms developed in Task 1.4 with airborne sunphotometer
data acquired while underflying plumes and hazes in downwind and
crosswind transects to study how aerosol sizes and masses evolve during
downwind transport, and how various sources contribute to regional mass
budgets. Efforts will be made to use the airborne sunphotometer water
vapor measurements to estimate the condensed water content of overlying
aerosols and thereby choose the most appropriate aerosol optical
property models to use in the algorithms that retrieve size distribution
and mass from optical depth spectra. This work will be closely
coordinated with modeling studies proposed to ACMAP by Dr. Robert
Chatfield of NASA Ames. Those studies will examine the effects of
meteorological processes (like dry boundary layer lifting and
cumulonimbus clouds) in determining trace gas and aerosol budgets in the
boundary layer and mid to upper troposphere using MM5 and the GRACES
model together with SAFARI 2000 data from MOPITT and lidars, among other
sources.

**3.2.4 Task 2.4: Aerosol Chemical-Physical-Optical Closure Studies.**
In addition to the satellite validation studies in Task 2.1 we plan to
conduct many closure studies that evaluate the mutual consistency of the
sunphotometer data products, other remote, radiometric, and in situ
measurements, and the models that link them. Examples include:

• Comparisons (as in Figure 5) between optical depth spectra measured by
airborne sunphotometer and calculated from in situ measurements of size
distribution, chemical composition (including condensed water), light
scattering, and absorption on the same aircraft profile,

• Comparisons (as in Figure 6) between size distributions retrieved from
airborne sunphotometer extinction or optical depth spectra and obtained
from in situ measurements (after correcting for such sampling effects as
evaporation, inlet size cutoffs, and composition-dependent calibration
factors),

• Comparisons between sunphotometer optical depths and those obtained
from lidar profiles using the backscatter-to-extinction values assumed
in the lidar analyses. These backscatter-to-extinction ratios will also
be compared to those derived from in situ measurements and the aerosol
models developed in Tasks 1.1 and 2.2. Effects of nonsphericity in soil
dust and seasalt aerosols will be considered, since lidar backscatter is
sensitive to nonsphericity. These results will be provided to the
development of PICASSO-CENA retrieval algorithms.

• Comparisons between radiative flux changes measured by SSFRs
(Pilewskie et al., 1998) and calculated from simultaneously measured
aerosol and gas properties. These comparisons will be analogous to those
in Figure 10, with the advantage that both the flux changes (from SSFR)
and the optical depths (from AATS-6 or --14) will be available in narrow
wavelength bands. Hence best-fit aerosol single scattering albedos
derived from analyses like those in Figure 10 will also be available as
a function of wavelength.

• Comparisons of aerosol single scattering albedos derived by a variety
of techniques, including (1) comparing lidar backscatter, sunphotometer
extinction, and in situ size distribution profiles (e.g., Redemann et
al., 1999a), (2) combining in situ measurements of aerosol light
scattering, absorption, and hygroscopicity (e.g., Hegg et al., 1997;
Hartley et al., 1999), (3) flux-change comparisons (e.g., Russell et
al., 1999b), and (4) the optical modeling in Tasks 1.1 and 2.2. A
comparison of results from techniques (1) and (2) is illustrated in
Figure 9.

The above examples are only illustrative. Our experience has been that
participation in multiplatform, multiagency campaigns like SAFARI 2000
and ACE Asia presents many opportunities for comparisons and closure
studies, some of which, though very important, were not anticipated in
advance. These closure studies, which typically entail collaborations
among several groups using disparate measurement and modeling
techniques, germinate during pre- and post-campaign science team
meetings as well as during the campaigns. We expect that this will be
the case during the proposed research.

**3.2.5 Task 2.5: Aerosol Radiative Effect Calculations.** We will
expand on the radiative transfer modeling carried out in Task 1.6. by
incorporating the aerosol optical properties actually measured by
satellite during the field campaigns (e.g., SAFARI 2000 third campaign
\[Aug-Sep 2000\], ACE Asia SEC \[Mar-Apr 2001\]; see Table 1). In
addition, aerosol parameters obtained from the multi-instrument closure
studies in Task 2.4 and those derived from the advanced mixed aerosol
optical models outlined in Tasks 1.1 and 2.2 will be used to drive the
radiative transfer codes. In this manner, the uncertainties in the
aerosol radiative effects will become smaller as the uncertainties in
the aerosol optical properties will be reduced through mutual
consistency (closure) studies.

**3.2.6 Task 2.6: Integrated Analyses and Assessments.** We expect that
these interdisciplinary investigations will be carried out partly
through collaborations among the CoIs and PI of this proposal and partly
through collaborations with other participants in SAFARI 2000, ACE Asia,
and MDAR (EOS/IDS and/or ACMAP). Here we sketch a few examples. The
satellite validation studies in Task 2.1 that relate to atmospheric
correction of ocean color data products will be tightly linked to the
algorithms for such products and will entail close collaboration with
CoI Kenneth Voss, who coauthored the Normalized Water-leaving Radiance
(atmospheric correction) algorithm for MODIS. However, these studies
would benefit from collaborations with investigators who use the ocean
color products to study ocean biogeochemical processes, and who
therefore see the biogeochemical implications of changes to ocean color
products via revised atmospheric corrections. Hence we will seek such
collaborations through Dr. Voss and Science Team activities. The same is
true regarding atmospheric correction of land surface products used to
study, for example, terrestrial ecosystems. Hence we will seek
collaboration with concerned ecosystem scientists, e.g., on the MODIS
land team or the SAFARI 2000 team. Our results on smoke plume particle
evolution and mass budgets obtained from realtime and post-campaign
sunphotometer flights on downwind and crosswind transects of plumes and
regional hazes should be of interest to SAFARI 2000 fire scientists who
conduct emission, evolution and mass budget studies (e.g., Scholes et
al., 1996; Ward et al., 1991, 1993); hence we will seek such
collaborations on the SAFARI 2000 team.

As noted in Task 2.4 above, not all the important collaborations can be
anticipated in advance; nevertheless, the success of our previous
collaborations with ecosystem scientists, atmospheric chemists, and
others in, e.g., ISLSCP, HAPEX-Sahel, BOREAS, AASE, TARFOX, and ACE 2
will inspire us to seek them out.

4.  **SCHEDULE**

<table>
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<tbody>
<tr class="odd">
<td rowspan="3">Task No.</td>
<td rowspan="3">Task or Event</td>
<td colspan="13">CY 2000</td>
<td colspan="15">CY 2001</td>
<td colspan="16">CY 2002</td>
<td></td>
</tr>
<tr class="even">
<td colspan="9">FY 2000</td>
<td colspan="15">FY 2001</td>
<td colspan="15">FY 2002</td>
<td colspan="5">03</td>
<td></td>
</tr>
<tr class="odd">
<td>J</td>
<td>F</td>
<td>M</td>
<td>A</td>
<td>M</td>
<td>J</td>
<td>J</td>
<td>A</td>
<td colspan="2">S</td>
<td>O</td>
<td>N</td>
<td colspan="3">D</td>
<td>J</td>
<td>F</td>
<td>M</td>
<td>A</td>
<td>M</td>
<td>J</td>
<td>J</td>
<td>A</td>
<td colspan="2">S</td>
<td>O</td>
<td>N</td>
<td colspan="3">D</td>
<td>J</td>
<td>F</td>
<td>M</td>
<td>A</td>
<td>M</td>
<td>J</td>
<td>J</td>
<td>A</td>
<td colspan="2">S</td>
<td>O</td>
<td>N</td>
<td colspan="3">D</td>
</tr>
<tr class="even">
<td>1.1</td>
<td>Optical modeling of smokes etc. for SAFARI</td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
</tr>
<tr class="odd">
<td>1.2</td>
<td>Ozone-aerosol algorithm and simulations</td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
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<td></td>
<td colspan="3"></td>
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<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
</tr>
<tr class="even">
<td>1.3</td>
<td>Water vapor retrieval refinement</td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
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<td></td>
<td colspan="3"></td>
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<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
</tr>
<tr class="odd">
<td>1.4</td>
<td>Aerosol column size distrib. &amp; mass alg. devel.</td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
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<td colspan="3"></td>
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<td colspan="3"></td>
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<td></td>
<td></td>
<td colspan="3"></td>
</tr>
<tr class="even">
<td>1.5</td>
<td>Quick-look analyses and comparisons</td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
<td></td>
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</tr>
<tr class="odd">
<td></td>
<td><blockquote>
<p>- Preparations</p>
</blockquote></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
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<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
</tr>
<tr class="even">
<td></td>
<td><blockquote>
<p>- Field analyses and comparisons</p>
</blockquote></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
</tr>
<tr class="odd">
<td>1.6</td>
<td>Preliminary aerosol radiative effect calculations</td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
</tr>
<tr class="even">
<td></td>
<td><h1 id="safari-2000"><u>SAFARI 2000</u></h1></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
</tr>
<tr class="odd">
<td></td>
<td><blockquote>
<p>- Workshop</p>
</blockquote></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
</tr>
<tr class="even">
<td></td>
<td><blockquote>
<p>- Third intensive air/ground campaign</p>
</blockquote></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
</tr>
<tr class="odd">
<td></td>
<td><blockquote>
<p>- Archiving, meeting presentations, journal special issues</p>
</blockquote></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
</tr>
<tr class="even">
<td></td>
<td>EOS/IDS plenary program review meeting</td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
</tr>
<tr class="odd">
<td></td>
<td>EOS/IDS disciplinary or ACMAP meeting</td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
</tr>
<tr class="even">
<td>2.1</td>
<td>Satellite validation studies</td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
</tr>
<tr class="odd">
<td>2.2</td>
<td>Optical model updates, including mineral dusts</td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
</tr>
<tr class="even">
<td>2.3</td>
<td>Aerosol evolution and budget studies</td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
</tr>
<tr class="odd">
<td>2.4</td>
<td>Aerosol chem-phys-optical closure studies</td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
</tr>
<tr class="even">
<td>2.5</td>
<td>Aerosol radiative effect calculations</td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
</tr>
<tr class="odd">
<td>2.6</td>
<td>Integrated analyses and assessments</td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
</tr>
<tr class="even">
<td></td>
<td><h1 id="ace-asia"><u>ACE Asia</u></h1></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
</tr>
<tr class="odd">
<td></td>
<td><blockquote>
<p>- Science Team meeting near ops center site</p>
</blockquote></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
</tr>
<tr class="even">
<td></td>
<td><blockquote>
<p>- Survey &amp; Evolution Component campaign</p>
</blockquote></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
</tr>
<tr class="odd">
<td></td>
<td><blockquote>
<p>- Data workshop/Science Team meeting</p>
</blockquote></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
</tr>
<tr class="even">
<td></td>
<td><blockquote>
<p>- Archiving, meeting presentations, journal special issues</p>
</blockquote></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td colspan="2"></td>
<td></td>
<td></td>
<td colspan="3"></td>
</tr>
<tr class="odd">
<td></td>
<td></td>
<td>J</td>
<td>F</td>
<td>M</td>
<td>A</td>
<td>M</td>
<td>J</td>
<td>J</td>
<td>A</td>
<td colspan="2">S</td>
<td>O</td>
<td>N</td>
<td colspan="3">D</td>
<td>J</td>
<td>F</td>
<td>M</td>
<td>A</td>
<td>M</td>
<td>J</td>
<td>J</td>
<td>A</td>
<td colspan="2">S</td>
<td>O</td>
<td>N</td>
<td colspan="3">D</td>
<td>J</td>
<td>F</td>
<td>M</td>
<td>A</td>
<td>M</td>
<td>J</td>
<td>J</td>
<td>A</td>
<td colspan="2">S</td>
<td>O</td>
<td>N</td>
<td colspan="3">D</td>
</tr>
<tr class="even">
<td></td>
<td></td>
<td colspan="14">CY 2000</td>
<td colspan="15">CY 2001</td>
<td colspan="14">CY 2002</td>
<td colspan="2"></td>
</tr>
</tbody>
</table>

######### REFERENCES 

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Anderson, B. E., et al., Aerosols from biomass burning over the South
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Andreae, M. O., T. W. Andreae, H. Annegarn, J. Beer, H. Cachier, P. le
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Bergstrom, R. W., and P. B. Russell, \"Estimation of aerosol radiative
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Browell, E. V., et al., Ozone and aerosol distributions and air mass
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Chatfield, R. B., J. A. Vastano, H. B. Singh, and G. Sachse, A general
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Chu, W. P., M. P. McCormick, J. Lenoble, C. Brogniez, and P. Pruvost,
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Chu, W. P., E.-W. Chiou, J. C. Larsen, L. W. Thomason, D. Rind, J. J.
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Cox \[formerly Steele\], H. M., *Information Retrieval from Solar
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Cunnold, D. M., M. P. McCormick, and the SAGE III Ozone ATBD Team*, SAGE
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1996.

Clark, D. K., H. R. Gordon, K. J. Voss, Y. Ge, W. Broenkow, and C.
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Clarke, A. D., Porter, J. N., Valero, F. P. J., and Pilweskie P. 1996.
Vertical profiles, aerosol microphysics, and optical closure during the
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Collins, D. R., Jonsson, H. H., Flagan, R. C., Seinfeld, J. H., Noone,
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accepted, 1999.

Dubovik, O., B. N. Holben, Y. J. Kaufman, M. Yamasoe, A. Smirnov, D.
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Durkee, P. A., Nielsen, K. E., Russell, P. B., Schmid, B., Livingston,
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Russell, L. M. this issue. Regional aerosol properties from satellite
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Eatough, D. J., Eatough, D. A., Lewis, L. and Lewis, E. A.. Fine
particulate chemical composition and light extinction at Canyonlands
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Res*. **101**, 19,515-19,531, 1996.

Ferrare, R., S. Ismail, E. Browell, V. Brackett, S. Kooi, M. Clayton, S.
H. Melfi, D. Whiteman, G. Schwemmer, K. Evans, P. Russell, J.
Livingston, B. Schmid, B. Holben, L. Remer, A. Smirnov, P. Hobbs,
Comparisons of aerosol optical properties and water vapor among ground
and airborne lidars and sun photometers during TARFOX, *J. Geophys.
Res*., submitted 1999.

Ferrare, R., S. Ismail, E. Browell, V. Brackett, S. Kooi, M. Clayton, P.
Hobbs, S. Hartley, J.P. Veefkind, P. Russell, J. Livingston, D. Tanre,
P. Hignett, Comparisons of LASE, aircraft, and satellite measurements of
aerosol optical properties and water vapor during TARFOX, *J. Geophys.
Res*., submitted 1999.

Fraser, R. S., and Y. J. Kaufman, The relative importance of aerosol
scattering and absorption in remote sensing, *IEEE Trans. Geosci. Remote
Sens., 23*, 625-633, 1985.

Fraser, R. S., S. Mattoo, E.-N. Yeh, and C. R. McClain, Algorithm for
atmospheric and glint corrections of satellite measurements of ocean
pigment, *J. Geophys. Res., 102*, 17,107-17,118, 1997.

Fu, Q., and K.N. Liou, On the Correlated k-Distribution Method for
Radiative Transfer in Nonhomogeneous Atmospheres, *J.Atmos.Sci*., 49,
2139-2156, 1992.

Fu, Q., and K.N. Liou, Parameterization of the Radiative Properties of
Cirrus Clouds, *J.Atmos.Sci*., 50, 2008-2025, 1993.

Fukushima, H., and M. Toratani, Asian dust aerosol: Optical effect on
satellite ocean color signal and a scheme of its correction, *J.
Geophys. Res., 102*, 17,119-17,130, 1997.

Giver, L. P., C. Chackerian, Jr., and P. Varanasi, Visible and
near-infrared H~2~O line intensity corrections for HITRAN 96*, J. Quant.
Spectrosc. Rad. Transfer*, submitted, 1999.

Gordon, H. R., Atmospheric correction of ocean color imagery in the
Earth Observing System era, *J. Geophys. Res., 102*, 17,081-17,106,
1997.

Halthore, R. N., T. F. Eck, B. N. Holben, and B. L. Markham, Sun
photometric measurements of atmospheric water vapor column abundance in
the 940-nm band, *J. Geophys. Res., 102*, 4343-4352, 1997.

Halthore, R. N., Nemesure, S., Schwartz, S. E., Imre, D. G., Berk, A.,
Dutton, E. G. and Bergin, M. H. 1998. Models overestimate diffuse
clear-sky surface irradiance: A case for excess atmospheric absorption.
*Geophys. Res. Lett.* **25**, 3591-3594, 1998.

Hartley, W. S., P. V. Hobbs, J. L. Ross, P. B. Russell and J. M.
Livingston, Properties of aerosols aloft relevant to direct radiative
forcing off the mid-Atlantic coast of the United States, *J. Geophys.
Res.* (2^nd^ Special Issue on TARFOX), submitted, 1999.

Hegg, D. A., J. Livingston, P. V. Hobbs, T. Novakov, and P. B. Russell,
Chemical apportionment of aerosol column optical depth off the
Mid-Atlantic coast of the United States, *J. Geophys. Res, 102,*
25,293-25,303, 1997.

Herman, J. R., P. K. Bhartia, O. Torres, C. Hsu, C. Seftor, and E.
Celarier, Global distributions of UV-absorbing aerosols from Nimbus
7/TOMS data, *J. Geophys. Res., 102*, 16,911-16,922, 1997.

Hignett, P., J. P. Taylor, P. N. Francis, and M. D. Glew, Comparison of
observed and modelled direct aerosol forcing during TARFOX*, J. Geophys.
Res.,* 104, 2279--2287, 1999.

Holben, B. N., et al., AERONET---A federated instrument network and data
archive for aerosol characterization, *Remote Sens. Environ., 66*, 1-16,
1998.

Hsu, N. C., J. R. Herman, O. Torres, B. N. Holben, D. Tanre, T. F. Eck,
A. Smirnov, B. Chatenet, and F. Lavenu, Comparisons of the TOMS aerosol
index with Sun-photometer aerosol optical thickness: Results and
applications, , *J. Geophys. Res., 104*, 6269-6279, 1999.

Huebert, B., T. Bates, J. Seinfeld, and J. Merrill, ACE Asia Survey and
Evolution Component (AA-SEC) NSF Large Field Program Scientific
Overview, omnibus proposal submitted to U.S. National Science
Foundation, 22 July 1999. Available at
<http://saga.pmel.noaa.gov/aceasia/si_nsf/index.html>.

Husar, R. B., J. M. Prospero and L. L. Stowe, Characterization of
tropospheric aerosols over the oceans with the NOAA advanced very high
resolution radiometer optical thickness operational product*, J.
Geophys. Res.,* 102, 16,889--16,909, 1997.

Kahn, R. R. West, D. McDonald, B. Rheingans, and M. I. Mishchenko,
Sensitivity of multiangle remote sensing observations to aerosol
sphericity, *J. Geophys. Res., 102*, 16,861-16,870, 1997.

Kato, S., Bergin, M. H., Laulainen, N., Ferrare, R., Turner, D.,
Michalsky, Charlock, T. P., Clothiaux, E. E., Mace, G. G. and Ackerman,
T. P. 1999. A comparison of the aerosol optical thickness derived from
ground-based and airborne measurements. *J. Geophys. Res.* (submitted).

Kaufman, Y. J., et al., Passive remote sensing of tropospheric aerosol
and atmospheric correction for the aerosol effect, *J. Geophys. Res.,
102*, 16,815-16,830, 1997a.

Kaufman, Y. J., et al., Operational remote sensing of tropospheric
aerosol over land from EOS-Moderate Resolution Imaging
Spectroradiometer, *J. Geophys. Res., 102*, 17,051-17,067, 1997b.

Kaufman, Y. J., et al., Smoke, Clouds, and Radiation-Brazil (SCAR-B)
experiment, *J. Geophys. Res., 103*, 31,783-31,808, 1998.

King M. D. and D. M. Byrne, A method for inferring total ozone content
from the spectral variation of total optical depth obtained with a solar
radiometer. *J. Atmos. Sci., 33*, 2242-2251, 1976.

King, M. D., D. M. Byrne, B. M. Herman, and J. A. Reagan. \"Aerosol Size
Distributions Obtained by Inversion of Spectral Optical Depth
Measurements.\" *J. Atmos. Sci.*, *35*, 2153--2167, 1978.

King, M. D., Y. J. Kaufman, D. Tanre, and T. Nakajima, Remote sensing of
tropospheric aerosols from space: Past, present and future, *Bull. Am.
Meteor. Soc*., in press, 1999.

Kuring, N., R. Simmon, and J. Acker, SeaWiFS observes transport of Asian
dust over the Pacific Ocean,
<http://daac.gsfc.nasa.gov/CAMPAIGN_DOCS/OCDST/asian_dust.html>, 1999.

Le Canut, P. M. O. Andreae, G. W. Harris, F. G. Weinhold, and T. Zenker,
Airborne studies of aerosol emissions from savanna fires in southern
Africa: 1. Aerosol emissions measured with a laser optical particle
counter, *J. Geophys. Res., 101*, 23,615-23,630,1996.

Leroy, M., et al., Retrieval of atmospheric properties and surface
bidirectional reflectances over land from POLDER/ADEOS, *J. Geophys.
Res., 102*, 17,023-17,038, 1997.

Livingston, J.M. and P.B. Russell, Comparison of satellite-inferred
(SAGE II) aerosol optical depths with corresponding airborne
sun-photometer optical depths, Preprint AIAA 27th Aerospace Sciences
Meeting, January 9-12, 1989, Reno Nevada.

Livingston, J. M., Kapustin, V. N., Schmid, B., Russell, P. B., Quinn,
P. K., Timothy, S. B., Philip, A. D., and Freudenthaler, V. this issue.
Shipboard sunphotometer measurements of aerosol optical depth spectra
and columnar water vapor during ACE 2. Tellus B accepted, 1999.

Martins, J. V., P. Artaxo, C. Liousse, J. S. Reid, P. V. Hobbs, and Y.
J. Kaufman, Effects of black carbon content, particle size, and mixing
on light absorption by aerosols from biomass burning in Brazil, *J.
Geophys. Res., 103*, 32,041-32,050, 1998.

Michalsky, J., C. Liljegren, and L. C. Harrison, A comparison of
sunphotometer derivations of total column water vapor and ozone to
standard measures of the same at the Southern Great Plains atmospheric
radiation measurement site, *J. Geophys. Res., 100*, 25,995-26,003,
1995.

Mishchenko, M. I., L. D. Travis, R. A. Kahn, and R. A. West, Modeling
phase functions for dustlike tropospheric aerosols using a shape mixture
of randomly oriented polydisperse spheroids, *J. Geophys. Res., 102*,
16,831-16,848, 1997.

Nakajima, T., and A. Higurashi, AVHRR remote sensing of aerosol optical
properties in the Persian Gulf region, summer 1991, *J. Geophys. Res.,
102*, 16,935-16,946, 1997.

Nakajima, T., M. Tanaka, M. Yamano, M. Shiobara, K. Arao, and Y.
Nakanishi, Aerosol optical characteristics in the yellow sand events
observed in May, 1982 in Nagasaki, II, Model, *J. Meteorol. Soc. Japan,
67*, 279-291, 1989.

Pilewskie, P., A. F. H. Goetz, D. A. Beal, R. W. Bergstrom, and P.
Mariani, Observations of the spectral distribution of solar irradiance
at the ground during SUCCESS, *Geophys. Res. Lett, 25*, 1141-1144, 1998.

Pilewskie, P., M. Rabette, R. Bergstrom, J. Marquez, B. Schmid, and P.
B. Russell, The discrepancy between measured and modeled downwelling
solar irradiance at the ground: Dependence on water vapor, *Geophys.
Res. Lett,* submitted, 1998.

Pilewskie, P., and F. P. J. Valero, Radiative effects of the smoke
clouds from the Kuwait oil fires, *J. Geophys. Res., 97*, 14,541-14,544,
1992.

Pilewskie, P., and F. P. J. Valero, Direct observation of excess solar
absorption by clouds, *Science, 267*, 1626-1629, 1995.

Pueschel, R.F., J.M. Livingston, P.B. Russell, D.A. Colburn, T.P.
Ackerman, D.A. Allen, B.D. Zak and W. Einfeld: Smoke optical depths:
magnitude, variability and wavelength dependence, *J. Geophys. Res.,
93*, 8388-8402, 1988.

Pueschel, R.F. and J.M. Livingston, Aerosol spectral optical depths: Jet
fuel and forest fire smokes, *J. Geophys. Res., 95*, 22,417-22,422,
1990.

Quijano, A.L., I.N. Sokolik, and O.B. Toon, Influence of the aerosol
vertical distribution on the retrievals of aerosol optical depth from
satellite radiance measurements, in *Workshop on Mineral Dust*, edited
by I.N. Sokolik, Boulder, CO, 1999.

Redemann J., R. P. Turco, R. F. Pueschel, M. A. Fenn, E. V. Browell, W.
B. Grant, A multi-instrument approach for characterizing the vertical
structure of aerosol properties: case studies in the Pacific basin
troposphere, *J.Geophys.Res*., 103, 23,287 - 23,298, 1998.

Redemann, J., R. Turco, Liou, Russell, Bergstrom, Schmid, Livingston,
Hobbs, Hartley, Ismail, Ferrare, Browell, Retrieving the Vertical
Structure of the Aerosol Complex Index of Refraction From Aerosol In
Situ and Remote Sensing Measurements During TARFOX, *J. Geophys. Res*.,
(2^nd^ Special Issue on TARFOX), submitted 1999a.

Redemann, J., R. Turco, Liou, Russell, Bergstrom, Hobbs, Browell, Case
Studies of the Vertical Structure of the Direct Aerosol Radiative
Forcing During TARFOX, *J. Geophys. Res*., (2^nd^ Special Issue on
TARFOX), submitted 1999b.

Redemann, J., P. Russell, and P. Hamill, Measurements and modeling of
aerosol absorption and single scattering albedo at ambient relative
humidity, Fall Meeting, Amer. Geophys. Union, submitted, 1999c.

Reid, J. S., and P. V. Hobbs, Physical and optical properties of young
smokes from individual biomass fires in Brazil, *J. Geophys. Res.*, 103,
32,013-32,030, 1998a.

Reid, J. S., P. V. Hobbs, R. J. Ferek, D. R. Blake, J. V. Martins, M. R.
Dunlap, and C. Liousse, Physical, chemical, and optical properties of
regional hazes dominated by smoke in Brazil, *J. Geophys. Res.*, 103,
32,059-32,080, 1998b.

Reid, J. S., P. V. Hobbs, C. Liousse, J. V. Martins, R. E. Weiss, and T.
F. Eck, Comparisons of techniques for measuring shortwave absorption and
black carbon content of aerosols from biomass burning in Brazil, *J.
Geophys. Res.*, 103, 32,031-32,040, 1998c.

Remer, L. A., Gassó, S., Hegg, D. A., Kaufman, Y. J. and Holben, B. N.
1997. Urban/industrial aerosol: Ground-based Sun/sky radiometer and
airborne in situ measurements, *J. Geophys. Res*. **102**,
16,849-16,859.

Remer, L. A., and Y. Kaufman, Dynamic aerosol model: Urban/industrial
aerosol, J. Geophys. Res., 103, 13,859-13,871, 1998a.

Remer, L. A., Y. Kaufman, and B. Holben, The size distribution of
ambient aerosol particles: Smoke vs. urban/industrial aerosol. *Global
Biomass Burning*, J. S. Levine, Ed., MIT Press, Cambridge, MA 519-530,
1996.

Remer, L. A., Y. Kaufman, B. Holben, A. M. Thompson, and D. McNamara, A
model of tropical biomass burning smoke aerosol size distribution, *J.
Geophys. Res.*, 103, 31,879-31,892, 1998b.

Russell, P. B., Airborne sunphotometry and integrated analyses of smoke
and haze aerosols, thin clouds, water vapor, and ozone in SAFARI 2000, A
Proposed Investigation Presented at NASA EOS SAFARI 2000 Workshop,
Boulder, CO, 12-14 May, 1999. Cost estimate and schedule submitted to
NASA EOS Program Science Office and NASA Radiation Science Program
Office, February 1999; available from the author, NASA Ames Research
Center, Moffett Field, CA 94035-1000.

Russell, P. B., et al., Measurements with an airborne, autotracking,
external-head sunphotometer, Preprint Volume, Sixth Conference on
Atmospheric Radiation, May 13-16, 1986, pp. 55-58, Amer. Meteor. Soc.,
Boston, MA, 1986.

Russell, P.B. et al., Pinatubo and pre-Pinatubo optical depth spectra:
Mauna Loa measurements, comparisons, inferred particle size
distributions, radiative effects, and relationship to lidar data. J.
Geophys. Res, 98, 22, 969-22,985, 1993a.

Russell, P. B. , and J. Heintzenberg, An overview of the ACE 2 Clear Sky
Column Closure Experiment (CLEARCOLUMN), *Tellus*, accepted, 1999.

Russell, P. B., P. V. Hobbs, and L. L. Stowe, Aerosol properties and
radiative effects in the United States east coast haze plume: An
overview of the Tropospheric Aerosol Radiative Forcing Observational
Experiment (TARFOX), *J. Geophys. Res., 104*, 2213-2222, 1999a.

Russell, P. B., J. M. Livingston, P. Hignett, S. Kinne, J. Wong, and P.
V. Hobbs, Aerosol-induced radiative flux changes off the United States
Mid-Atlantic coast: Comparison of values calculated from sunphotometer
and in situ data with those measured by airborne pyranometer, *J.
Geophys. Res., 104*, 2289-2307, 1999b.

Russell, P.B., J.M. Livingston, R.F. Pueschel, J.A. Reagan, E.V.
Browell, G.C. Toon, P.A. Newman, M.R. Schoeberl, L.R. Lait, L. Pfister,
Q. Gao, and B.M. Herman, Post-Pinatubo optical depth spectra vs.
latitude and vortex structure: Airborne tracking sunphotometer
measurements in AASE II. *Geophys Res. Lett, 20*, 2571-2574, 1993b.

Russell, P. B., J. M. Livingston, R. F. Pueschel, J. B. Pollack, S. L.
Brooks, P. J. Hamill, J. J. Hughes, L. W. Thomason, L. L. Stowe, T.
Deshler, E. G. Dutton, and R. W. Bergstrom. Global to microscale
evolution of the Pinatubo volcanic aerosol, derived from diverse
measurements and analyses. *J. Geophys. Res., 101*, 18,745-18,763, 1996.

Russell, P. B., M. P. McCormick, and the SAGE III Aerosol ATBD Team*,
SAGE III Algorithm Theoretical Basis Document (ATBD): Aerosol Data
Products, Version 1.0*, NASA Langley Research Center, Hampton, VA,
(http://eospso.gsfc.nasa.gov/atbd/sagetables.html) November 15, 1996c.

Schmid B., K. J. Thome, P. Demoulin, R. Peter, C. Mätzler, and J.
Sekler. \"Comparison of Modeled and Empirical Approaches for Retrieving
Columnar Water Vapor from Solar Transmittance Measurements in the 0.94
Micron Region\". *Journal of Geophysical Research* , *101*, 9345-9358,
1996*.*

Schmid, B., J. J. Michalsky, R. N. Halthore, M. C. Beauharnois, L. C.
Harrison, J. M. Livingston, and P. B. Russell, Comparison of aerosol
optical depth from four solar radiometers during the Fall 1997 ARM
Intensive Observation Period, *Geophys. Res. Lett., 27*, 2725-2728,
1999a.

Schmid, B., Livingston, J. M., Russell, P. B., Durkee, P. A., Collins,
D. R., Flagan, R. C., Seinfeld, J. H., Gasso, S., Hegg, D. A., Ostrom,
E., Noone, K. J., Welton, E. J., Voss, K., Gordon, H. R., Formenti, P.,
and Andreae, M. O.. Clear sky closure studies of lower tropospheric
aerosol and water vapor during ACE 2 using airborne sunphotometer,
airborne in-situ, space-borne, and ground-based measurements. *Tellus*
accepted, 1999b.

Scholes, R.J., D.E. Ward and C.O. Justice: Emissions of trace gases and
aerosol particles due to vegetation burning in southern hemisphere
Africa. *J. Geophys. Res., 101*, 23,677-23,682, 1996.

Sokolik I.N., and O.B. Toon, Incorporation of mineralogical composition
into models of the radiative properties of mineral aerosol from UV to IR
wavelengths. J. Geophys. Res., 104, 9423-9444, 1999.

Sokolik I.N., Nuts and bolts of radiative forcing by mineral dust.
IGACtivities Newsletter, Issue 17, 12-14, May 1999.

Spanner, M.A., R.C. Wrigley, R.F. Pueschel, J.M. Livingston and D.S.
Colburn, Determination of atmospheric optical properties during the
first international satellite land surface climatology project field
experiment*. J. Spacecraft and Rockets, 27*, 373-379, 1990.

Steele, H. M., and R. P. Turco, The measurement and prediction of
aerosol extinction: implications for SAGE II ozone concentrations and
trends*, J. Geophys. Res*., in press, 1997.

Swap, R. J., and H. J. Annegarn, Southern African Regional Science
Initiative: SAFARI 2000: Science Plan (Draft available at
<http://safari.gecp.virginia.edu/schedule/ftptoc.html)>, 1999.

Swap, R., H. Annegarn, M. Scholes, and C. Justice, SAFARI-2000: A
Southern African Regional Science Initiative, *IGACtivities Newsletter
15*, IGAC Core Project Office, Cambridge, MA, 1998a.

Swap, R., J. Privette, M. King, D. Starr, T. Suttles, H. Annegarn, M.
Scholes, and C. Justice, SAFARI 2000: A Southern African Fire/Atmosphere
Regional Science Initiative, *Earth Observer 10*, No. 6, 31-34, EOS
Project Science Office, NASA Goddard Space Flight Center, Greenbelt, MD,
1998b.

Tanre, D., L. A. Remer, Y. J. Kaufman, S. Mattoo, P. V. Hobbs, J. M.
Livingston, P. B. Russell, and A. Smirnov, Retrieval of aerosol optical
thickness and size distribution over ocean from the MODIS airborne
simulator during TARFOX, *J. Geophys. Res., 104*, 2261-2278, 1999.

Thomason L. W., 1985: Extinction of near infrared solar radiation as a
means for remote determination of atmospheric water vapor. Ph. D.
dissertation, University of Arizona Tucson. pp. 122.

Toon, O., E. Browell, B. Gary, L. Lait, J. Livingston, P. Newman, R.
Pueschel, P. Russell, M. Schoeberl, G. Toon, W. Traub, F.P.J. Valero, H.
Selkirk, J. Jordan, Heterogeneous reaction probabilities, solubilities,
and the physical state of cold volcanic aerosols, *Science, 261*,
1136-1140, 1993.

Veefkind, J. P., G. de Leeuw, P. A. Durkee, P. B. Russell, P. V. Hobbs,
and J. M. Livingston, Aerosol optical depth retrieval using ATSR-2 and
AVHRR data during TARFOX, *J. Geophys. Res., 104*, 2253-2260, 1999.

Vermote, E. F., et al., Atmospheric correction of visible to
middle-infrared EOS-MODIS data over land surfaces: Background,
operational algorithm and validation, *J. Geophys. Res., 102*,
17,131-17,142, 1997.

Wanner, W., et al., Global retrieval of bidirectional reflectance and
albedo over land from EOS MODIS and MISR data: Theory and algorithm, *J.
Geophys. Res., 102*, 17,143-17,162, 1997.

Ward, D. E., and C. C. Hardy, Smoke emissions from wildland fires,
*Environ. Int., 17*, 117-134, 1991.

Ward, D. E., and L. F. Radke, Emission measurements from vegetation
fires: A comparative evaluation of methods and results, in *Fire in the
Environment: The Ecological, Atmospheric and Climatic Importance of
Vegetation Fires* edited by P. J. Crutzen and J. G. Goldammer, John
Wiley, Chichester, England, 1993.

Welton, E.J., K.J. Voss, H.R. Gordon, H. Maring, A. Smirnov, B. Holben,
B. Schmid, J.M. Livingston, P.B. Russell, P.A. Durkee, P. Formenti, M.O.
Andrea, and O. Dobovik, Ground-based lidar measurements of aerosols
during ACE 2: Instrument description, results, and comparisons with
other ground based and airborne measurements, *Tellus*, accepted, 1999.

Wrigley, R.C., M.A. Spanner, R.E.. Sly, R.F. Pueschel, and H.R.
Aggarwal, Atmospheric correction of remotely sensed image data by a
simplified model. J. Geophys. Res., 97, 18797-18814, 1992.

Yamasoe, M. A., Y. J. Kaufman, O. Dubovik, L. A. Remer, B. N. Holben,
and P. Artaxo, Retrieval of the real part of the refractive index of
smoke particles from Sun/sky measurements during SCAR-B, *J. Geophys.
Res., 103*, 31,893-31,902, 1998.

5.  **BUDGET**

6.  **STAFFING, RESPONSIBILITIES, AND VITAE**

Dr. Philip B. Russell will be Principal Investigator. As such, he will
supervise the work, lead the planning, and participate in the modeling
and analyses, as well as selected presentations and publications. He
will be responsible for the completion of the work within budget and
schedule. John Livingston and Drs. Beat Schmid, Jens Redemann, and
Robert Bergstrom will participate in the development and use of
algorithms and models and will lead and/or participate in specified data
analyses, presentations, and publications. Specifically, Drs. Russell
and Redemann will co-lead Tasks 1.1 and 2.2, Dr. Schmid will lead Tasks
1.2, 1.3, and 2.4, Mr. Livingston will lead Tasks 1.4 and 1.5, Drs.
Bergstrom and Redemann will co-lead Tasks 1.6 and 2.5, and Dr. Russell
will lead Tasks 2.1, 2.3, and 2.6.

Prof. Kenneth Voss, who coauthored the Algorithm Theoretical Basis
Document for the MODIS Normalized Water-leaving Radiance (atmospheric
correction) data product will provide a link to the MODIS Ocean data
product algorithms, access to quick-look MODIS ocean data products, and
advice and oversight on the use of the airborne sunphotometers in
validating MODIS ocean algorithms and furnishing complementary data to
MODIS ocean investigations. Dr. Didier Tanre, a member of the MODIS
Atmosphere Science Team, will provide a link to that team and will
provide advice and oversight on the use of the airborne sunphotometers
in validating MODIS and MODIS Airborne Simulator (MAS) aerosol products
and furnishing complementary data to MODIS atmospheric investigations.
Dr. Tanre's institution, USTL, has endorsed his participation in NASA
research projects, including development of MODIS algorithms and use of
MODIS and MODIS Airborne Simulator data in integrated
satellite/aircraft/ground field experiments. He makes frequent trips to
the US for this purpose, and he will be available to interact with other
team members and attend program reviews on these trips. Dr. Jay Herman,
the PI for Meteor-3M/TOMS and for TOMS Aerosol/UV projects, will provide
access to quick-look TOMS aerosol and ozone products, as well as advice
and oversight on the use of the airborne sunphotometers in validating
TOMS aerosol and ozone products and furnishing complementary data to
TOMS atmospheric investigations.

**(a) Philip B. Russell**

**Vita**

B.A., Physics, Wesleyan University (1965, Magna cum Laude; Highest
Honors). M.S. and Ph.D., Physics, Stanford University (1967 and 1971,
Atomic Energy Commission Fellow). M.S., Management, Stanford University
(1990, NASA Sloan Fellow).

Postdoctoral Appointee, National Center for Atmospheric Research
(1971-72, at University of Chicago and NCAR). Physicist to Senior
Physicist, Atmospheric Science Center, SRI International (1972-82).
Chief, Atmospheric Experiments Branch (1982-89), Acting Chief and Acting
Deputy Chief, Earth System Science Division (1988-89), Chief,
Atmospheric Chemistry and Dynamics Branch (1989-95), Research Scientist
(1995-present), NASA Ames Research Center.

Currently, Co-coordinator for the CLEARCOLUMN component of the Second
Aerosol Characterization Experiment (ACE 2) of the International Global
Atmospheric Chemistry (IGAC) Project. Member, Science Team for Global
Aerosol Climatology Project (GACP; Investigation Title: Improved
Exploitation of Field Data Sets to Address Aerosol Radiative-Climatic
Effects and Development of a Global Aerosol Climatology). Member,
Science Teams for SAGE II and SAGE III (satellite sensors of
stratospheric aerosols, ozone, nitrogen dioxide, and water vapor).
Primary responsibilities: analyses of volcanic aerosol properties and
effects, development of the SAGE III Aerosol Algorithm Theoretical Basis
Document (ATBD), and experiment design and data analyses to validate the
satellite measurements.

Previously, NASA Ames Associate Fellow (1995-96, awarded for excellence
in atmospheric research).

Previously, Coordinator for IGAC's Tropospheric Aerosol Radiative
Forcing Observational Experiment (TARFOX). Convenor of TARFOX Special
Sessions, Spring 1997 Meeting, American Geophysical Union (AGU).
Coordinator, TARFOX special issues of *Journal of Geophysical Research*
(1998-99). Program Co-Chair, International Specialty Conference on
Visual Air Quality, Aerosols, and the Global Radiation Balance
(Bartlett, New Hampshire, 10/1997). Member, Direct Aerosol Radiative
Forcing Committee of IGAC Focus 8: Atmospheric Aerosols (1996-98).

Previously, Editor (1993, 1996) and Editor-in-Chief (1994-95),
*Geophysical Research Letters*; Member, Board of Editors and Atmospheric
Science Executive Committee, American Geophysical Union. Guest Editor,
*Journal of Geophysical Research* Special Issues on \"Midlatitude
Stratospheric Dynamics and Cross-Tropopause Exchange,\" \"Tropical
Stratosphere-Troposphere Exchange,\" and \"SAGE II Aerosol and Ozone
Data Validation and Initial Data Use\" (1988-93). Convenor, Sessions on
the Atmospheric Effects of 1991 Pinatubo Eruption, AGU Fall Meeting
(1992). Organizer and/or report editor, Workshops on \"Requirements for
a Very-High-Altitude Aircraft for Atmospheric Research,\" \"Scientific
Application of Remotely Piloted Aircraft Measurements of Radiation,
Water Vapor, and Trace Gases to Climate Studies,\" and \"Mission
Measurement Strategies for the Subsonic Assessment Program\" (1989-94).
Member, Interagency Task Group on Airborne Geoscience (1987-89), Member,
American Institute of Aeronautics and Astronautics (AIAA) Losey
Atmospheric Sciences Award Selection Committee, (1986-87), Member, AIAA
Atmospheric Environment Technical Committee (1984-90), Invited
Participant, World Meteorological Organization Experts Meeting on
Aerosols and their Climatic Effects (1983), Invited Participant, NOAA
Workshop on Global Large Aerosols (1982), Chair, American Meteorological
Society International Committee on Laser Atmospheric Studies (1979-82,
Member, 1978-82), Member, National Research Council Committee on Army
Basic Research (1979-81), Member, American Meteorological Society
Committee on Radiation Energy (1979-81).

Previously, Project Scientist, Small High-Altitude Science Aircraft
(SHASA) Project to develop the Perseus A Remotely Piloted Aircraft (RPA,
1992-94), Member, Science/Aeronautics Seam Team of NASA Ames
Reorganization Team (1994), Member, Ad Hoc Committee on the NASA
Environmental Research Aircraft and Sensor Technology (ERAST) Program
(1993-4), Member, NASA Red Team on Remote Sensing and Environmental
Monitoring of Planet Earth (1992-3), Leader, NASA Ames Earth Science
Advanced Aircraft (ESAA) Team (1990-94), Member, National Aero-Space
Plane (NASP) Committee on Natural Environment (1988-94), Member, NASA
Ames Strategy and Tactics Committee (1986-87), Chair, NASA Ames
Atmospheric Science Strategy Review Team (1986-87), Manager, NASA
Stratosphere-Troposphere Exchange Project (STEP, 1983-93), Member, NASA
Solar-Terrestrial Observatory Science Study Group (1979-80), Member,
NASA Atmospheric Lidar Working Group (1977-79) , Member, NASA Spacelab 2
Investigations Review Panel (1977).

NASA Exceptional Service Medal (1988, for managing
Stratosphere-Troposphere Exchange Project), NASA Space Act Award (1989,
for invention of Airborne Autotracking Sunphotometer), and NASA Group
Achievement Awards (1994, for Stratospheric Photochemistry, Aerosols and
Dynamics Expedition; 1991, for Airborne Arctic Stratospheric Expedition;
and 1989, for Airborne Antarctic Ozone Experiment). Graham Prize (1965,
outstanding undergraduate in natural science, Wesleyan University).
Member, Phi Beta Kappa and Sigma Xi.

Patent, \"Airborne Tracking Sunphotometer Apparatus and System\" ( U.S.
Pat. No. 4,710,618, awarded 1987)

####### PUBLICATIONS

(Selected from 81 peer-reviewed publications)

Russell, P. B., and J. Heintzenberg, An overview of the ACE 2 Clear Sky
Column Closure Experiment (CLEARCOLUMN), *Tellus*, accepted, 1999.

Bergstrom, R. W., and P. B. Russell, Estimation of aerosol radiative
effects over the mid-latitude North Atlantic region from satellite and
in situ measurements. *Geophys. Res. Lett., 26*, 1731-1734, 1999.

Russell, P. B., P. V. Hobbs, and L. L. Stowe, Aerosol properties and
radiative effects in the United States Mid-Atlantic haze plume: An
overview of the Tropospheric Aerosol Radiative Forcing Observational
Experiment (TARFOX), *J. Geophys. Res*., *104*, 2213-2222, 1999a.

Russell, P. B., J. M. Livingston, P. Hignett, S. Kinne, J. Wong, and P.
V. Hobbs, Aerosol-induced radiative flux changes off the United States
Mid-Atlantic coast: Comparison of values calculated from sunphotometer
and in situ data with those measured by airborne pyranometer, *J.
Geophys. Res.,* 104, 2289-2307, 1999b.

Russell, P. B., S. Kinne and R. Bergstrom, \"Aerosol Climate Effects:
Local Radiative Forcing and Column Closure Experiments,\" *J. Geophys.
Res.,* *102*, 9397-9407, 1997.

Russell, P. B., J. M. Livingston, R. F. Pueschel, J. J. Bauman, J. B.
Pollack, S. L. Brooks, P. Hamill, L. W. Thomason, L. L. Stowe, T.
Deshler, E. G. Dutton, and R. W. Bergstrom. \"Global to Microscale
Evolution of the Pinatubo Volcanic Aerosol, Derived from Diverse
Measurements and Analyses.\" *J. Geophys. Res.*, *101*, 18,745-18,763,
1996a.

Russell, P.B., L. Pfister, and H.B. Selkirk. \"The Tropical Experiment
of the Stratosphere-Troposphere Exchange Project (STEP): Science
Objectives, Operations, and Summary Findings.\" *J. Geophys. Res.*,
*98*, 8563-8589, 1993.

Russell, P.B., J. M. Livingston, R. F. Pueschel, J. A. Reagan, E.V.
Browell, G. C. Toon, P.A. Newman, M.R. Schoeberl, L.R. Lait, L. Pfister,
Q. Gao, and B. M. Herman. \"Post-Pinatubo Optical Depth Spectra vs.
Latitude and Vortex Structure: Airborne Tracking Sunphotometer
Measurements in AASE II.\" *Geophys. Res. Lett.*, *20*, 2571-2574, 1993.

Russell, P.B., and M.P. McCormick. \"SAGE II Aerosol Data Validation and
Initial Data Use: An Introduction and Overview.\" *J. Geophys. Res.*,
*94*, 8335-8338, 1989.

Russell, P.B., M.P. McCormick, T.J. Swissler, J.M. Rosen, D.J. Hofmann,
and L.R. McMaster. \"Satellite and Correlative Measurements of the
Stratospheric Aerosol: III. Comparison of Measurements by SAM II, SAGE,
Dustsondes, Filters, Impactors, and Lidar.\" *J. Atmos. Sci.*, *41*,
1791-1800, 1984.

Russell, P.B., T.J. Swissler, M.P. McCormick, W.P. Chu, J.M. Livingston,
and T.J. Pepin. \"Satellite and Correlative Measurements of the
Stratospheric Aerosol: I. An Optical Model for Data Conversions.\" *J.
Atmos. Sci.,* *38*, 1270-1294, 1981.

Russell, P.B., J.M. Livingston, and E.E. Uthe. \"Aerosol-Induced Albedo
Change: Measurement and Modeling of an Incident.\" *J. Atmos. Sci.*,
*36,* 1587-1608, 1979.

**(b) Beat Schmid**

## Vita

Senior Research Scientist, Bay Area Environmental Research Institute

MS-245, NASA Ames Research Center, Moffett Field, CA 94035-1000

Phone: 650 604 5933 Fax: 650 604 3625, E-Mail: bschmid@mail.arc.nasa.gov

## Relevant Education

• Diploma, Physics (1991, Institute of Applied Physics, University of
Bern, Switzerland. Thesis: \"Monitoring Vegetation Development in
Switzerland by Means of NOAA/AVHRR-Satellite Data\")

• Ph. D., Physics (1995, Institute of Applied Physics, University of
Bern, Switzerland. Thesis: \"Sun Photometry, a Tool for Monitoring
Atmospheric Parameters\")

•June 1995-April 1997: Research assistant, University of Bern, Institute
of Applied Physics.

•Oct. 1995 -Jan. 1996: Visiting scientist at University of Arizona,
Optical Sciences Center, Tucson, AZ.

• May 1997-Present: Senior Research Scientist, Bay Area Environmental
Research Institute / NASA Ames Research Center, Moffett Field, CA.

## Qualifications Summary

• Expert in the field of ground-based and airborne sunphotometry

• Extensive experience in radiometric calibration

• Strong background in the measurement and the theory of atmospheric
aerosol, gases and radiation

• Experience in Earth and atmospheric remote sensing from UV to
micro-wave

• Excellent communication and public speaking skills

## Publications

Schmid B., C. Mätzler C., and E. Schanda, 1991: Temporal Evolution of
Vegetation Indices and Atmospheric Effects, *Proceedings of the 11th
EARSeL-Symposium, 3-5 July 1991*, Graz, Austria, pp. 355-368.

Peter R., and B. Schmid, 1993, Comparison of Columnar Water Vapor
Determined from Microwave Emission and Solar Transmission Measurements.
*Proceedings of Topical Symposium on Combined Optical-Microwave Earth
and Atmosphere Sensing*, March 22-25, Albuquerque, NM, pp. 193-197.

Schmid B., R. Peter R., and C. Mätzler, 1993: Intercomparisons of
Columnar Water Vapor Retrievals Obtained with a Sun photometer and a
Microwave Radiometer, *PIERS\'93*, July 12-16, Pasadena, CA.

Schmid B., and C. Wehrli, 1994: High Precision Calibration of a Sun
Photometer Using Langley Plots Performed at Jungfraujoch (3580 m) and
Standard Irradiance Lamps. *Proceedings of IGARSS'94*, August 8-12,
Pasadena, CA, pp. 2'314-2'316.

Schmid B., and C. Wehrli, 1995: Comparison of Sun Photometer Calibration
by Langley Technique and Standard Lamp. *Applied Optics*, Vol. 34, No.
21, 4500-4512.

Schmid B., K. J. Thome, P. Demoulin, R. Peter, C. Mätzler, and J.
Sekler, 1996: Comparison of Modeled and Empirical Approaches for
Retrieving Columnar Water Vapor from Solar Transmittance Measurements in
the 0.94 Micron Region. *Journal of Geophysical Research*, Vol. 101, No.
D5, 9345-9358.

Demoulin P., B. Schmid, G. Roland and C. Servais, 1996: Vertical Column
Abundance and Profile Retrievals of Water Vapor Above the Jungfraujoch.
*Atmospheric Spectroscopic Aplications Workshop*, Reims, France,
September 1996, pp. 131-134.

Schmid B., C. Mätzler, A. Heimo, and N. Kämpfer, 1997: Retrieval of
Optical Depth and Size Distribution of Tropospheric and Stratospheric
Aerosols by Means of Sun Photometry. *IEEE Transactions on Geoscience
and Remote Sensing,* Vol 35, No. 1, 172-182.

Schmid B., J.M. Livingston, P.B. Russell, and P.A. Durkee, 1997: \"Three
Dimensional Measurements of Lower Tropospheric Aerosol Optical Depth
Spectra and Water Vapor Amounts during ACE 2 by Means of Airborne
Sunphotometry.\" *EOS Trans. Amer Geophys. Union*, 78, F97, 1997.

Livingston J.M., V. Kapustin, B. Schmid, P.B. Russell, P.A. Durkee, T.S.
Bates, and P.K. Quinn, 1997: \"Shipboard Sunphotometer Measurements of
Aerosol Optical Depth Spectra During ACE 2.\" *EOS Trans. Amer Geophys.
Union*, 78, F97-98.

Schmid B., P.R. Spyak, S.F. Biggar, Ch. Wehrli, J. Sekler, T. Ingold, C.
Mätzler, and N. Kämpfer, 1998: "Evaluation of the applicability of solar
and lamp radiometric calibrations of a precision Sun photometer
operating between 300 and 1025 nm." *Appl. Opt.,* Vol 37, No. 18,
3923-3941.

**(c) Jens Redemann**

## Vita

Research Scientist, Bay Area Environmental Research Institute

MS-245, NASA Ames Research Center, Moffett Field, CA 94035-1000

Phone: (650) 604-6259 Fax: (650) 604-3625, email:
<jredemann@mail.arc.nasa.gov>

# PROFESSIONAL EXPERIENCE

  ---------------------------------- ------------------------------------
  Research Scientist                 April 1999 to present

  ---------------------------------- ------------------------------------

> Bay Area Environmental Research Institute, San Francisco.

  ---------------------------------- ------------------------------------
  Research Assistant                 May 1995 to March 1999

  ---------------------------------- ------------------------------------

> **University of California, Los Angeles, Department of Atmospheric
> Sciences.**

  ------------- ---------------------------------------------------------
  Lecturer      Jan. 1999 to March 1999

  ------------- ---------------------------------------------------------

**University of California, Los Angeles, Department of Atmospheric
Sciences.**

  ---------------------------------- ------------------------------------
  Tutor                              1997 to 1998

  ---------------------------------- ------------------------------------

**Ivy West Educational Services, Marina Del Rey, CA.**

  ---------------------------------- ------------------------------------
  Research Assistant                 June 1994 to April 1995

  ---------------------------------- ------------------------------------

**Free University of Berlin, Germany. Department of Physics.**

  ---------------------------------- ------------------------------------
  Consultant                         July 1989 to August 1993

  ---------------------------------- ------------------------------------

Zander Cleanroom Technology, Nuremberg, Germany.

# EDUCATION

+----------------------------------+-----------------------------------+
| Ph.D. in Atmospheric Sciences.   | > 1999                            |
+----------------------------------+-----------------------------------+

> University of California, Los Angeles. Specialization: atmospheric
> physics and chemistry.

+----------------------------------+-----------------------------------+
| M.S. in Atmospheric Sciences.    | > 1997                            |
+----------------------------------+-----------------------------------+

> University of California, Los Angeles. Specialization: atmospheric
> physics and chemistry.

+----------------------------------+-----------------------------------+
| M.S. in Physics.                 | > 1995                            |
+----------------------------------+-----------------------------------+

> Free University of Berlin, Germany. Specialization in experimental
> physics and mathematics.

# RelevanT research experience

-   Developed inversion algorithms (C and IDL) and data analysis tools
    for aircraft-based lidar and sunphotometer measurements during field
    experiments (PEM, TARFOX).

-   Compared remotely sensed data to aerosol in situ measurements and
    devised techniques to retrieve the vertical structure of aerosol
    optical properties and radiative effects.

-   Involved in the development of a multi-wavelength, ground-based
    lidar system at the Free University of Berlin, Germany.

-   Provided solutions to scientific and numerical problems pertaining
    to aerosol physics and performed validation measurements relevant to
    Clean Room Technology for the computer chip industry.

-   Specialized course work in atmospheric sciences, geophysical fluid
    dynamics, cloud physics, radiative transfer and remote sensing.

# HONORS

+----------------------------------------------------------+-----------+
| > Invited Speaker at the Atmospheric Chemistry           | ####      |
| > Colloquium for Emerging Senior Scientists (ACCESS V).  | June 1999 |
+----------------------------------------------------------+-----------+
| > Outstanding Student Paper Award, American Geophysical  | > 1998    |
| > Union - fall meeting.                                  |           |
+----------------------------------------------------------+-----------+
| > NASA Global Change Research Fellowship Awards.         | >         |
|                                                          | 1996-1998 |
+----------------------------------------------------------+-----------+
| > UCLA Neiburger Award for excellence in the teaching of | > 1997    |
| > the atmospheric sciences.                              |           |
+----------------------------------------------------------+-----------+

# ORGANIZATIONS

American Association for Aerosol Research, American Geophysical Union,
Co-president of the UCLA - Atmospheric Sciences Graduate Student Group.

# SELECTED PUBLICATIONS

Redemann, J., R.P. Turco, K.N. Liou, P.B. Russell, R.F. Pueschel, E.V.
Browell. Evidence of Positive Aerosol Radiative Forcing Events in the
Pacific Basin Troposphere, 1999 (in preparation for
*[GRL]{.underline}*).

Redemann, J., R.P. Turco, K.N. Liou, P.B. Russell, R.W. Bergstrom, B.
Schmid, J.M. Livingston, P.V. Hobbs, S. Ismail, E.V. Browell. Retrieving
the Vertical Structure of the Aerosol Complex Index of Refraction From
Aerosol In Situ and Remote Sensing Methods During TARFOX, 1999
(submitted, 2nd *[TARFOX JGR special issue]{.underline}*).

Redemann, J., R.P. Turco, K.N. Liou, P.B. Russell, R.W.Bergstrom, P.V.
Hobbs, E.V. Browell. Case Studies of the Vertical Structure of the
Aerosol Radiative Forcing During TARFOX, 1999 (submitted, 2nd *[TARFOX
JGR special issue]{.underline}*).

Redemann, J., R.P. Turco, R.F. Pueschel, M.A. Fenn, E.V. Browell and
W.B. Grant. A Multi-Instrument Approach for Characterizing the Vertical
Structure of Aerosol Properties: Case Studies in the Pacific Basin
Troposphere, *[J. Geophys. Res]{.underline}., 103,* 23,287 - 23,298,
1998. (peer-reviewed)

Redemann, J., R.P. Turco, R.F. Pueschel, E.V. Browell, W.B. Grant.
Combining Data From Lidar and In Situ Instruments to Characterize the
Vertical Structure of Aerosol Optical Properties, Presented at the
Nineteenth International Laser Radar Conference, Annapolis, MD, July
6-10, 1998, *[NASA/CP-1998-207671/PT1]{.underline}*, pp.95-99, 1998.

Redemann, J., R.P. Turco, R.F. Pueschel, E.V. Browell, W.B. Grant.
Comparison of Aerosol Measurements by Lidar and In Situ Methods in the
Pacific Basin Troposphere, in '*[Advances in Atmospheric Remote Sensing
with Lida]{.underline}r*', A. Ansmann, R.Neuber, P.Rairoux, U.Wandinger
(eds.), pp.55-58, Springer, Berlin, 1996. (peer-reviewed)

Pueschel, R.F.; D.A. Allen, C. Black, S. Faisant, G.V. Ferry, S.D.
Howard, J.M. Livingston, J. Redemann, C.E. Sorensen, S. Verma, Condensed
Water in Tropical Cyclone "Oliver", 8 February 1993, *[Atmospheric
Research]{.underline}*, 38, pp.297-313, 1995. (peer-reviewed)

**(d) John Livingston**

**Vita**

Senior Research Meteorologist, Geoscience and Engineering Center,
Advanced Development Division

SRI International, Menlo Park, CA 94025

Specialized Professional Competence

Atmospheric physics and meteorology; atmospheric radiometry; computer
simulation of atmospheric remote sensing systems; numerical analysis and
inversion of in-situ and remotely sensed atmospheric data

Representative Research Assignments at SRI (Since 1978)

Acquisition and analysis of spectral solar radiance measurements

Validation of satellite particulate extinction measurements (SAM II,
SAGE I, and SAGE II), and corresponding studies of the global
distribution of stratospheric aerosols

Inversion of spectral extinction measurements to derive aerosol
size-distribution parameters

Analysis of *in situ* measurements of stratospheric and tropospheric
aerosols

Modeling and analysis of Differential Absorption Lidar measurements of
tropospheric ozone

Simulation of passive sensor radiance measurements to infer range to an
absorbing gas

Experimental study of aerosol effects on solar radiation using remote
sensors

Error analysis and simulation of lidar aerosol measurements

Analysis of lidar propagation through fog, military smoke, and dust
clouds

Evaluation of the lidar opacity method for enforcement of stationary
source emission standards

Weather forecasting for large-scale air pollution field study

Testing and evaluation of an offshore coastal dispersion computer model

Application of objective wind field and trajectory models to
meteorological measurements

Other Professional Experience

Research assistant, University of Arizona Institute of Atmospheric
Physics (1974-1977)

NASA Kennedy Space Center (1975-1976): participant in thunderstorm
electrification studies

Academic Background

B.S. summa cum laude in geology (1974), University of Notre Dame

M.S. in atmospheric sciences (1977), University of Arizona

M.B.A. with highest honors (1992), Santa Clara University

University of Notre Dame Year-in-Japan Program (1971-1972), Sophia
University, Tokyo

Professional Associations and Honors

American Meteorological Society; American Geophysical Union

Publications

Author or co-author of more than two dozen articles in refereed
scientific journals, in addition to numerous contributions in conference
proceedings, and SRI reports

**(e) Robert W. Bergstrom**

## Vita

B.S., Mechanical Engineering, Oregon State University (1968). M.S. and
Ph.D., Mechanical Engineering, Purdue University (1969 and 1972). J.D.,
Law, Stanford University (1983). Member of the California Bar
(1983-present).

Post-Doctoral Fellow, Mainz University, Germany (1972-1973). National
Research Associate, NASA Ames Research Center (1974-1977) . Senior
Scientist, Systems Application Inc., San Rafael CA (1997 -- 1980).
Associate, Law Firm of McCutchen, Doyle, Brown and Enersen, San
Francisco (1983-1984). Assistant Regional Counsel, U.S. EPA, Region IX,
San Francisco, (1984-1992).

Founder of the Bay Area Environmental Research Institute, San Francisco,
CA (1992). Currently, Director of Research. Guest Investigator on the
UARS Satellite Science Team using the satellite data to explore the
effects of the Pinatubo aerosol on atmospheric radiation. Principal
Investigator on several Cooperative Agreements with NASA Ames Research
Center. Currently investigating the effects of aerosols on atmospheric
radiation during ACE 2.

# Selected Publications

Bergstrom, R.W. and P.B. Russell, Estimation of aerosol radiative
effects over the mid-latitude North Atlantic region from satellite and
in situ measurements, **Geophys. Res. Lett**., [26]{.underline},
1731-1734, (1999).

Sokolik, I., O.B. Toon and R.W. Bergstrom, "Modeling the Radiative
Characteristics of

Airborne Mineral Aerosols at Infrared Wavelengths," **J. Geophys.
Res**., [103]{.underline}, 8813-8826, (1998).

Pilewskie, P. et al. (including R.W. Bergstrom), Observations of the
spectral distribution of solar irradiance at the ground During SUCCESS,"
**Geophys. Res. Lett**[.]{.underline}, [25]{.underline}, 1141-1144,
1998.

Russell, P.B. S. Kinne and R.W. Bergstrom: "Aerosol climate effects:
Local radiative forcing and column closure experiments," **J.
Geophys.Res**, [102]{.underline}, 9397, (1997)

Kinne, S. et al (including R.W. Bergstrom), \"Cirrus Cloud Radiative and
Microphysical Properties from Ground Observations during FIRE '91,\"
**J. Atmos. Sci.,** [54]{.underline}, 2320 (1997).

Seiegnuer, C., et al (including R.W. Bergstrom), "Formulation of a
Second-Generation Reactive Plume and Visibility Model," **J. Air & Waste
Man. Assoc**., [47]{.underline}, 176 (1997)

Russell, P.B. et al (including R.W. Bergstrom), "Global to microscale
evolution of the Pinatubo volcanic aerosol derived from diverse
measurement and analyses," **J. Geophys. Res**., [101]{.underline},
18,745 (1996)

Wu, X.H., S. Seignuer and R. W. Bergstrom "Evaluation of a sectional
representation of aerosol size distributions for calculations of optical
properties," **J. Geophys. Res**. [101]{.underline}, 19277, (1996)

Bergstrom, R.W., B.L. Babson and T.P. Ackerman, \"Calculation of
Multiply Scattered Radiation in Clean Atmospheres,\" **Atmos.
Environ**., [15]{.underline}, 1821 (1981).

Bergstrom, R.W. and A.C. Cogley, \"Scattering of Emitted Radiation from
Inhomogeneous and Nonisothermal Layers,\" **J. Quant. Spect. Rad.
Trans**., [21]{.underline}, 279 (1979).

Cogley A.C. and R.W. Bergstrom, \"Numerical Results for the Thermal
Scattering Functions,\" **J. Quant. Spect. Rad. Trans**.,
[21]{.underline}, 263 (1979).

Bergstrom R.W. and J.T. Peterson, \'Comparison of Observed and Predicted
Solar Radiation in an Urban Area,\" **J. App. Met**., [16]{.underline},
1107 (1977).

Bergstrom, R.W. \"Extinction and Absorption Coefficients of Atmospheric
Aerosols as a Function of Particle Size,\" **Beiträge zur Physik der
Atmosphäre**, [46]{.underline}, 223 (1973).

Bergstrom, R.W. \"Comments on the Estimation of the Absorption
Coefficients of Atmospheric Aerosols,\" **Beiträge zur Physik der
Atmosphäre**, [46]{.underline}, 198 (1973).

Bergstrom, R.W. \"Prediction of the Spectral Absorption and Extinction
Coefficients of An Urban Air Pollution Aerosol Model,\" **Atmos.
Environ**[.]{.underline}, [6]{.underline}, 247 (1972).

**(f) Kenneth J. Voss**

## Vita

Professor, Department of Physics

University of Miami, Coral Gables Fl. 33124

Phone: (305) 284 2323 Fax: (305) 284 4222, email:
<voss@physics.miami.edu>

B.S. Physics, Washington State University (1979), Ph. D., Physics, Texas
A&M University, (1984).

Postgraduate Research Physicist (1984-1987, Visibility Laboratory,
Scripps Institution of Oceanography, Univ. of Cal. San Diego). Assistant
Research Optical Oceanographer, (1987-1989, Institute of Marine
Resources, Scripps Institution of Oceanography). Assistant Professor to
Professor, University of Miami (1989-present).

Topical Editor for Applied Optics(1994 -- present). Chairman,
Atmospheric and Oceanic Optics Technical Group, Optical Society of
America (1994-1995). Vice Chairman, Atmospheric and Oceanic Optics
Technical Group, Optical Society of America (1993).

Recent Refereed journal articles (last 2 years):

C. Hu and K. J. Voss, "Measurement of solar stimulated fluorescence in
natural waters", 1998, Limnol. and Ocean., **43**: 1198 - 1206.

K J. Voss, W. M. Balch, K. A. Kilpatrick, Scattering and attenuation
properties of [Emiliania]{.underline} [huxleyi]{.underline} cells and
their detached coccoliths, 1998, Limnol. and Ocean., **43**: 870-876.

K. D. Moore, K. J. Voss, and H. R. Gordon, "Spectral reflectance of
Whitecaps: Instrumentation, calibration, and performance in coastal
waters", 1998, J. Atm. and Ocean. Techn., **15**: 496-509.

J. S. Bartlett, K. J. Voss, S. Sathyendranath, and A. Vodacek, " Raman
scattering by pure water and seawater", 1998, Applied Optics, **37**:
3324 - 3332.

Y. Liu and K. J. Voss, "Polarized radiance distribution measurements of
skylight: II. experiment and data", 1997, Applied Optics, **36**: 8753 -
8764.

C. Hu and K. J. Voss, "*In situ* measurement of Raman scattering in
clear ocean water", 1997, Applied Optics, **36**: 6962 - 6967.

D. K. Clark, H. R. Gordon, K. J. Voss, Y. Ge, W. Broenkow, and C. Trees,
"Validation of Atmospheric Correction over the Oceans", 1997, J.
Geophys. Res., **102**: 17,209-17,217.

K. J. Voss and Y. Liu, "Polarized radiance distribution measurements of
skylight: I. system description and characterization.", 1997, Applied
Optics, **36** :6083-6094.

B. J. Frew and K. J. Voss, "Measurement of the Point Spread Function in
a layered system", 1997, Applied Optics, **36**: 3335-3337.

**(g) Didier Tanre**

## Vita

> **[Education:]{.underline}**
>
> M.Sc. in Physics in 1975 and Thèse de 3ème Cycle and Doctorat d\'État
> in Atmospheric Physics in 1977 and 1982, respectively; all from the
> Université des Sciences et Techniques de Lille, France.
>
> **[Research and academic employment:]{.underline}**
>
> Joined CNRS (Centre National de la Recherche Scientifique), collocated
> with the Laboratoire d\'Optique Atmosphérique at the Université des
> Sciences et Techniques de Lille, Villeneuve d\'Ascq, France, as a
> Research Scientist in 1982.
>
> NRC Resident Research Associate at NASA Goddard Space Flight center
> from 1989 through 1991.
>
> **[Research interest]{.underline}**
>
> Remote sensing of aerosol from space,
>
> Experience in ground based-measurements (AERONET).
>
> Experience in radiative transfer theory (5S and 6S codes)
>
> **[Memberships]{.underline}**
>
> Member of Earth Observing System - MODIS science team.
>
> Member of the POLDER Science Team on ADEOS
>
> Member of the GEWEX Radiation Panel
>
> Chairman of the French Satellite Remote Sensing Program
>
> **[Honors and Awards]{.underline}**
>
> Transactions Prize Paper Award (1993) from the IEEE Geoscience and
> Remote Sensing Society for best paper of the year in the IEEE
> Transactions on Geoscience and Remote Sensing.
>
> **[Recent publications:]{.underline}**

**1997 :**

Bouffies S., Bréon F.M., Tanré D., Dubuisson P., Atmospheric Water Vapor
Estimate by a Differential absorption Technique with the POLDER
Instrument, J. Geophys. Res., 102, 3831-3841, 1997.

Cachorro V. E., Tanré D., The Correlation between Particle Mass Loading
and Extinction: Application to Desert Dust Aerosol Content Estimation,
Rem. Sens. Environ., 60, 187-194, 1997.

Liousse C., Dulac F., Cachier H., Tanré D., Remote Sensing of
Carbonaceous Aerosol Production by African Savanna Biomass Burning, J.
Geophys. Res., 102, 5895-5911, 1997.

Roujean J.L., Tanré D., Bréon F.M., Deuzé J.L., Retrieval of land
surface parameters for GCM from POLDER bidirectional measurements during
HAPEX-SAHEL, J. Geophys. Res., 102, 11201-11218, 1997.

Soufflet V., Tanré D., Royer A., O\'neil N., Remote Sensing of aerosols
over boreal forest and lake from AVHRR/NOAA data, Rem. Sens. Environ.,
60, 22-34, 1997.

Vermote E. F., Tanré D., Deuzé J.L, Herman M., Morcrette J.J., Second
Simulation of the Satellite Signal in the Solar Spectrum: An Overview,
IEEE Transactions on Geoscience and Remote Sensing, 35, 675-686, 1997.

**1997: (JGR/Numéro Spécial: Passive remote sensing of tropospheric
aerosols and atmospheric corrections of the aerosol effect)**

Bréon, F.M., J.L. Deuzé, D. Tanré, M. Herman, Validation of spaceborne
estimates of aerosol loading from sunphotometer measurements with
emphasis on the polarization, J. Geophys. Res., 17187-17196, 1997.

Herman M., Deuzé J.L., Devaux C., Goloub P., Bréon F.M., Tanré D.,
Remote Sensing of Aerosols over Land Surfaces Including Polarization
Measurements: Applications to POLDER Measurements, J. Geophys. Res.,
17039-17050, 1997.

Kaufman Y.J., Tanré D., Gordon H.R., Nakajima T., Lenoble J., Frouin R.,
Grassl H., Herman B.M., King M., Teillet P.M., Passive Remote Sensing of
Tropospheric Aerosol and Atmospheric correction for the Aerosols
Effects, J. Geophys. Res., 16815-16830, 1997.

Kaufman Y.J., Tanré D., Remer L., Vermote E., Holben B.N., Operational
Remote Sensing of Tropospheric Aerosols over the Land from EOS-MODIS, J.
Geophys. Res., 17051-17068, 1997.

Leroy, M., J.L. Deuzé, F.M. Bréon, O. Hautecoeur, M. Herman, J.C.
Buriez, D. Tanré, S. Bouffiès, P. Chazette, And J.L. Roujean, Retrieval
of Atmospheric Properties and Surface Bidirectional Reflectances Over
the Land From POLDER/ADEOS, J. Geophys. Res., 17023-17038, 1997.

Tanré D, Kaufman Y.J., Herman M., Mattoo S., Remote sensing of aerosols
properties over oceans using the MODIS/EOS spectral radiances, J.
Geophys. Res., 16971-16988, 1997.

Vermote E., N. El. Saleous, C.O. Justice, Y.J. Kaufman, J.L. Privette,
L. Remer, J.C. Roger, D. Tanré, Atmospheric corrections of visible to
middle-infrared EOS-MODIS data over land surfaces: background,
operational algorithm and validation, J. Geophys. Res., 17131-17142,
1997.

**1998:**

Alpert P., Kaufman Y.J., Shay-El Y., Tanré D., Da Silva A., Schubert S.,
Joseph Y.H., Quantification of dust-forced heating of the lower
troposphere, Nature, 395, 367-370, 1998.

Dubovik O., Holben B.N., Kaufman Y.J., Yamasoe M., Smirnov A., Tanré D.,
Slutsker I., Single-scattering albedo of smoke retrieved from the
sky-radiance and solar transmittance measured from the ground, J.
Geophys. Res., 31903-31924 , 1998.

Holben B.N., Eck T.F., Slutsker I., Tanré D., Buis J.P. Setzer A.,
Vermote E., Reagan J.A., Kaufman Y., Nakajima T., Lavenu F., Jankowiak
I. AERONET-A Federated Instrument Network and Data Archive for Aerosol
Characterization, Rem. Sens. Environ., 66, 1-16, 1998.

Plana-Fattori A., Legrand M., Tanré D., Devaux C., Vermeulen A.,
Dubuisson P., Estimating of the Atmospheric Water Vapor Content from Sun
Photometer Measurements, J. Appl. Meteor., 37, 790-804, 1998.

Wald A., Kaufman Y. Tanré D., Gao B.C., Daytime and nighttime detection
of mineral dust over desert using infrared spectral contrast, J.
Geophys. Res., 103, 32307-32313, 1998.

**1999:**

Deuzé J.L., M Herman, P. Goloub, D. Tanré, A. Marchand, Characterization
of aerosols over ocean from POLDER/ADEOS-1, Geophys. Res. Lett., 26,
1421-1424, 1999.

Goloub P, D. Tanré, J.L. Deuzé, M. Herman, A. Marchand, F.M. Bréon,
Validation of the first algorithm applied for deriving the aerosol
properties over the ocean using the POLDER/ADEOS measurements, IEEE
Transactions on Geoscience and Remote Sensing, 37, 1586-1596, 1999.

Hsu N.C., J.R. Herman, O. Torres, B.N. Holben, D. Tanré, T.F. Eck, A.
Smirnov, B. Chatenet, F. Lavenu, Comparison of the TOMS Aerosol Index
with Sunphotometer Aerosol Optical Thickness: Results and Applications,
J. Geophys. Res., 104, 6269-6279, 1999.

Tanré D., L.A. Remer, Y.J. Kaufman, S. Mattoo, P.V. Hobbs, J.M.
Livingston, P.B. Russell, A. Smirnov, Retrieval of Aerosol Optical
Thickness and Size Distribution Over Ocean from the MODIS Airborne
Simulator during TARFOX, J. Geophys. Res., 104, 2261-2278, 1999.

Vesperini M., Bréon F.M., Tanré D., Atmospheric water vapor content from
space-borne POLDER measurements, IEEE Transactions on Geoscience and
Remote Sensing, 37, 1613-1619, 1999.

*In press*

Chiapello I., P. Goloub, D. Tanré, J. Herman, O. Torres, A. Marchand,
Aerosol detection by TOMS and POLDER over oceanic regions, J. Geophys.
Res., accepté, 1999.

Kaufman Y.J., A. Karnieli, D. Tanré, Detection of dust over deserts
using satellite data in solar wavelengths, IEEE Transactions on
Geoscience and Remote Sensing, accepté, 1999.

King M.D., Y. J. Kaufman, D. Tanré, and T. Nakajima, Remote Sensing of
Tropospheric Aerosols from Space: Past, Present, and Future, Bulletin of
the American Meteorological Society, accepté, 1999.

**(h) Jay R. Herman**

## Vita

RESEARCH AREA Ion chemistry, earth ionosphere, planetary ionospheres,

EXPERIENCE: wave propagation in plasmas, stratospheric chemistry and
modeling, radiative transfer, atmospheric spectroscopy, uv solar flux
measurements, ozone inversion algorithms, and long-term ozone trend
analysis.

Recent Experience Instrument design for spaceflight (e.g., Triana
spectroradiometer), UV radiation at the Earth's surface, aerosols, and
cloud properties.

PRESENT POSITION: **Project Scientist** for Triana mission

**Principal Investigator** for TOMS/Meteor project now in post-launch
phase.

**Principal Investigator** for FM-5 TOMS project

**Principal Investigator** for TOMS UV and aerosol projects

> **Lead Scientist** for TOMS Project Data Acquisition, Validation and
> Analysis:

TOMS-SBUV/Nimbus-7 US

TOMS/Meteor US/Russia

TOMS/Earth Probes US

TOMS/ADEOS US/Japan

> Atmospheric Chemistry and Dynamics Branch, NASA/Goddard Space Flight
> Center, Code 916.

EDUCATION: 1959 B.S. Physics with minor in mathematics, (obtained with
high honor) Clarkson College, Potsdam, New York

1963 M.S. Physics Penn. State Univ., State College, PA

1965 Ph.D. Physics Penn. State Univ., State College, PA

Recent Publications (1997 to 1999)

1\. "Earth Surface Reflectivity Climatology at 340 nm to 380 nm from
TOMS Data", J. R. Herman and E. A. Celarier, J. Geophys. Res.**102**,
28003-28011, 1997.

2\. "Global Distribution of UV-Absorbing Aerosols From Nimbus-7/TOMS
Data", J.R. Herman, P.K. Bhartia, O.Torres, C. Hsu, C. Seftor, E.
Celarier, J.Geophys. Res., **102**, 16,911-16,922, 1997.

3\. "Derivation of Aerosol Properties From Satellite Measurements of
Backscattered Ultraviolet Radiation. Theoretical Basis", O. Torres, P.K.
Bhartia, J.R.Herman, and Z. Ahmad, J.Geophys. Res., 103, 17099-17110,
1998.

4\. "The Meteor-3/total ozone mapping spectrometer version 7 data set:
Cal;ibration and analysis", C.J. Seftor, G. Jaross, J.R. Herman, X.Gu,
L. Moy, S.L. Taylor,and C.G. Wellemeyer, J. Geophys. Res., **102**,
19,247-19,256, 1997.

5\. "Satellite estimation of spectral surface UV irradiance in the
presence of tropospheric aerosols 1:Cloud free case", N.A. Krotkov, P.K.
Bhartia, J.R. Herman, V. Fioletov, J. Kerr, J. Geophys. Res., **103**,
8779-8793 1998.

6\. Total ozone/UV-B monitoring and forecasting: Imapct of clouds and
the horizontal resolution of satellite retrievals", J.R. Ziemke., J.R.
Herman, J.L. Stanford, and P.K.Bhartia,, J. Geophys. Res., **103**,
3865-3871, 1998.

7\. "New TOMS instrument measures ozone and aerosols" J. Kaye, R.D.
McPeters, J.R. Herman, P.K. Bhartia, and A.J. Krueger, EOS Transactions,
AGU, 79, 57, 1998.

8\. "NIMBUS-7/TOMS detection of mineral dust over the north Africa and
the eastern north Atlantic Ocean", I. Chiapello, J.R.Herman, C. Hsu, J.
Prospero, Accepted by J. Geophys. Res. 1999.

9\. "Comparisons of the TOMS aerosol index with sun photometer aerosol
optical thickness", N. Christina Hsu, Jay R. Herman, O.Torres, B.N.
Holben,D. Tanre, T.F. Eck, A.Smirnov, B. Chatenet, and F. Lavenu, J.
Geophys. Res. 104, 6269-6279, 1999.

10\. "The Distribution of UV Radiation at the Earth's Surface From TOMS
Measured UV-Backscattered Radiances**",** J.R. Herman, N. Krotkov,E.
Celarier, D. Larko and G. Labow, J. Geophys. Res. 104, 12059-12076,
1999.

11\. UV Radiation an the Earth's Surface" Chapter 9, J. R. Herman,
McKenzie, S. Diaz, J. Kerr, S. Madronich, and G. Seckmeyer, WMO 1999,
UNEP/WMO Scientific Assessment of Ozone Depletion: 1999, edited by D. L.
Albritton, R. T. Watson, and P. J. Aucamp*, WMO Global Ozone Res. and
Monit. Proj*., Geneva, 1999.

12\. \"Response of the Climatic Temperature to Dust Forcing, inferred
from TOMS Aerosol Index and the NASA Assimilation Model\", P. Alpert, J.
Herman, Y. J. Kaufman and I. Carmona, Atmos. Res., 1999 (accepted).

13\. "Satellite and ground-based study of 1997 Indonesian forest fire
aerosols", Teruyuki, Nakajima, a. Higurashi, N. Takeuchi, and J.R.
Herman, Accepted, Geophysical Research Letters26, 2421_2424, 1999.

14\. "Satellite detection of smoke aerosols over a snow/ice surface by
TOMS", Hsu, N.C., J.R. Herman, J.F. Gleason, O. Torres., C.J. Seftor,
Geophys. Res. Lett., 26, 1165-1168, 1999.

15\. "Regional Changes in Global UV Reflectivity from Clouds and
Aerosols", J. R. Herman, D. Larko, and J. Ziemke, submitted to, J.
Geophys. Res., 1999.

16\. "Comparison of daily UV doses estimated from Nimbus-7/TOMS
measurements and ground-based spectroradiometric data", Kalliskota, S.,
J. Kaurola, P. Taalas, J.R. Herman, E. Celarier, and N. Krotkov,
accepted, J. Geophys. Res., 1999.

17\. "Determination of Radiative Forcing of Saharan Dust Using Combined
TOMS and ERBE Data", N. Christina Hsu, Herman, J.R., and Clark Weaver,
submitted to J. Geophys. Res., 1999.

18\. "Satellite estimation of spectral surface UV irradiance 2: Effect
of horizontally homogeneous clouds", N. Krotkov, Herman, J.R., Bhartia,
P.K., Ahmad, Z., Fioletov, V., submitted to J. Geophys. Res., 1999.

19\. "Erythemally weighted UV trends over northern latitudes derived
from Nimbus 7 TOMS measurements", J.R. Ziemke, S. Chandra, J. Herman,
and C. Varotsos, submitted to J. Geophys. Res., 1999.

20\. "Quasi-biennial oscillation in UV-B solar irradiance at
Thessaloniki and San Diego from ground-based and satellite
measurements", C. Zerefor, M. Tsortziou, J. Herman, A. Bias, submitted
to Geophys. Res. Lett, 1999.

7.  **CURRENT SUPPORT**

As specified in Appendices B and A of the NRA, other projects being
conducted by the Principal Investigator (PI) are identified by title,
funding agency, and ending date, and other support for co-investigators
is listed. For projects supported by NASA's Office of Earth Science, the
subject is described, to distinguish it from the research proposed here.

**8.1 Principal Investigator, Philip B. Russell**

**NASA RTOP 229-10-32-00**, PI P. Russell. \$125,000 in FY99,
10/95-9/00, 2 person-months/17% LoE per year. "SAGE III Science Team
Activities." Principal activities include developing the SAGE III
Aerosol Algorithm Theoretical Basis Document (ATBD), planning and
preparing for validation/correlative measurements, using the new
14-channel sunphotometer as a test-bed for SAGE III algorithm
development (including ozone-aerosol separation), and investigating
retrieval algorithms for aerosol particle surface area, volume, and
effective radius.

**NASA RTOP 622-44-10-10**, PI P. Russell. \$150,000 in FY99,
10/95-9/99, 3 person-months/25% LoE per year. "Aerosol Radiative Effect
Analyses for TARFOX and ACE 2." Airborne sunphotometer and related data
acquired in TARFOX and ACE 2 are analyzed to reduce uncertainties in
aerosol effects on climate. PI also serves as International Global
Atmospheric Chemistry Project (IGAC) Coordinator for TARFOX.

**NASA RTOP 622-44-75-10**, PI P. Russell. \$175,000 in FY99,
10/98-9/01, 3 person-months/25% LoE per year. "Improved Exploitation of
Field Data Sets to Address Aerosol Radiative-Climatic Effects and
Development of a Global Aerosol Climatology." Airborne sunphotometer and
related data acquired in TARFOX and ACE 2 are analyzed to reduce
uncertainties in aerosol effects on climate.

**NASA RTOP 621-45-51-10**, PI P. Russell. \$57,000 in FY99, 10/99-9/00,
2 person-months/17% LoE per year. "Composite Data Analyses for Pinatubo
Volcanic Aerosols." SAGE II, UARS, and other data are combined to
develop a composite data set describing the evolution of the Pinatubo
volcanic aerosol.

**NOAA Interagency Transfer of Funds NAAZ0000700110**, PI P. Russell.
\$99,000 in FY99, 4/97-3/00, 2 person-months/17% LoE per year.
"Evaluation of the Direct Effects of Anthropogenic Aerosols on the
Radiation Balance of the Atmosphere." The Ames 6-channel autotracking
sunphotometer and two handheld instruments were installed on a ship for
measurements in ACE 2. Measurements are being analyzed with other data
sets to improve understanding of the radiative/climatic effects of
European and African aerosols. PI also serves as Co-coordinator for the
CLEARCOLUMN component of ACE 2.

**8.2 Co-Investigators**

**8.2.1 Co-Investigators at NASA Ames**

+------------+---------------+----+-------+-------+--------+--------+
| **A        | **Short       | *  | **Per |       |        |        |
| gency/Task | Title**       | *E | son-M |       |        |        |
| No.\***    |               | nd | onths |       |        |        |
|            |               | Da | per   |       |        |        |
|            |               | te | Year/ |       |        |        |
|            |               | ** | Level |       |        |        |
|            |               |    | of    |       |        |        |
|            |               |    | Eff   |       |        |        |
|            |               |    | ort** |       |        |        |
+------------+---------------+----+-------+-------+--------+--------+
|            |               |    | J.    | B.    | J.     | R.     |
|            |               |    | Livin |       |        |        |
|            |               |    | gston | S     | Re     | Ber    |
|            |               |    |       | chmid | demann | gstrom |
+------------+---------------+----+-------+-------+--------+--------+
| NASA RTOP  | SAGE III      | 9/ | 4/33% | 5/42% | 1/8%   |        |
|            | Science Team  | 00 |       |       |        |        |
| 22         |               |    |       |       |        |        |
| 9-10-32-00 |               |    |       |       |        |        |
+------------+---------------+----+-------+-------+--------+--------+
| NASA RTOP  | TARFOX/ACE 2  | 9/ | 2/17% | 2/25% | 3/25%  | 4/33%  |
|            | Analyses      | 99 |       |       |        |        |
| 62         |               |    |       |       |        |        |
| 2-44-10-10 |               |    |       |       |        |        |
+------------+---------------+----+-------+-------+--------+--------+
| NASA RTOP  | TARFOX/ACE 2  | 9/ | 2/17% | 3/25% | 6/50%  |        |
|            | Analyses in   | 01 |       |       |        |        |
| 62         | GACP          |    |       |       |        |        |
| 2-44-75-10 |               |    |       |       |        |        |
+------------+---------------+----+-------+-------+--------+--------+
| NASA RTOP  | SAGE II       | 9/ |       |       |        |        |
|            | Science Team  | 00 |       |       |        |        |
| 62         |               |    |       |       |        |        |
| 1-45-51-10 |               |    |       |       |        |        |
+------------+---------------+----+-------+-------+--------+--------+
| NOAA       | ACE 2 Ship    | 9/ | 4/33% | 2/17% | 2/17%  | 2/16%  |
| I          |               | 99 |       |       |        |        |
| nteragency | Sunphotometry |    |       |       |        |        |
| Transfer   | & Integrated  |    |       |       |        |        |
| of Funds   | Analyses      |    |       |       |        |        |
| NAAZ       |               |    |       |       |        |        |
| 0000700110 |               |    |       |       |        |        |
+------------+---------------+----+-------+-------+--------+--------+

\*PI, Award Amount, Period of Performance, Project Title, and Short
Abstract are described in preceding Section 8.1.

8.2.2 Other Co-Investigators

[Kenneth Voss]{.underline}

ONR (PI K. Voss) 0/1/98 - 9/30/00, \$235,651, 2.5 person months/year.
"Bi-Directional reflectance measurements in the coastal environment".

NASA (PI Howard Gordon), 1/1/91-12/31/01, \$14,648,439 4.5 person
months/year. "Ocean observation with EOS/Modis: Algorithm Development
and Post Launch Studies".

[Didier Tanre]{.underline}

Dr. Tanre currently receives no funding from NASA, and no support for
him is requested by this proposal. As noted in Section 7, Dr. Tanre's
institution, USTL, has endorsed his participation in NASA research
projects, and he makes frequent trips to the US for this purpose. He
will be available to interact with other team members and attend program
reviews on these trips.

[Jay Herman]{.underline}

As noted in his vita above, Dr. Herman is a civil servant at NASA GSFC,
currently working as Project Scientist for the Triana mission, Principal
Investigator for the TOMS/Meteor project, Principal Investigator for the
FM-5 TOMS project, Principal Investigator for TOMS UV and aerosol
projects, and Lead Scientist for TOMS Project Data Acquisition,
Validation and Analysis. This proposal requests no funding for Dr.
Herman personally; the time he contributes to the proposed effort (see
Section 7) will be covered by his current projects at GSFC. To
facilitate his contribution, this proposal requests salary and travel
support for a programmer at GSFC, to provide quick access to TOMS
aerosol and ozone data, and to travel to NASA Ames to collaborate with
Ames team members regarding TOMS algorithms and validation.

**8.3 Other Agencies to Which This Proposal, or Parts Thereof, Have Been
Submitted.**

No part of this proposal has been submitted to any other agency.

**Table 1.** Satellites, Sensors, Data Products, and Planned Field
Campaigns Relevant to This Proposal

1 = Primary validation opportunity. 2 = Secondary validation
opportunity.

3 = Opportunity to investigate effects of strong vertical gradients and
dense aerosols on retrievals.

+----------+--------------+----------+-----------------+-------------+
| **SA     | **DATA       | **FIELD  |                 |             |
| TELLITES | PRODUCTS**   | CAM      |                 |             |
| AND      |              | PAIGNS** |                 |             |
| S        |              |          |                 |             |
| ENSORS** |              |          |                 |             |
+----------+--------------+----------+-----------------+-------------+
| # E      |              | SAFARI   | African Dust    | ACE Asia    |
| OS Terra |              | 2000     | Plume and       | Survey and  |
|          |              | Third    | Water-leaving   | Evolution   |
|          |              | C        | Radiance        | Component   |
|          |              | ampaign, | Opportunities   |             |
|          |              | Aug-Sep  | on SAFARI 2000  | (AA-SEC),   |
|          |              | 2000     | Transits, Aug & |             |
|          |              |          | Sep 2000        | Mar-Apr     |
|          |              |          |                 | 2001        |
+----------+--------------+----------+-----------------+-------------+
| MODIS    | Aerosol      | 1        | 1               | 1           |
|          | optical      |          |                 |             |
|          | depth        |          |                 |             |
|          | spectra &    |          |                 |             |
|          | R~eff~       |          |                 |             |
+----------+--------------+----------+-----------------+-------------+
|          | Normalized   | 2        | 1               | 1           |
|          | w            |          |                 |             |
|          | ater-leaving |          |                 |             |
|          | radiance     |          |                 |             |
|          | (Atmos.      |          |                 |             |
|          | Corr.)       |          |                 |             |
+----------+--------------+----------+-----------------+-------------+
|          | Water vapor  | 1        | 1               | 1           |
|          | column       |          |                 |             |
+----------+--------------+----------+-----------------+-------------+
|          | Ozone column | 1        | 1               | 1           |
+----------+--------------+----------+-----------------+-------------+
| MISR     | Aerosol      | 1        | 1               | 1           |
|          | optical      |          |                 |             |
|          | depth (4 λ)  |          |                 |             |
|          | and type     |          |                 |             |
+----------+--------------+----------+-----------------+-------------+
|          | Normalized   | 2        | 1               | 1           |
|          | w            |          |                 |             |
|          | ater-leaving |          |                 |             |
|          | radiance     |          |                 |             |
|          | (Atmos.      |          |                 |             |
|          | Corr.)       |          |                 |             |
+----------+--------------+----------+-----------------+-------------+
| MOPITT   | CO profile   | 3        | 3               | 3           |
+----------+--------------+----------+-----------------+-------------+
|          | CH~4~ column |          |                 |             |
+----------+--------------+----------+-----------------+-------------+
| ASTER    | (Atmospheric | 2        | 2               | 2           |
|          | corrections  |          |                 |             |
|          | use MODIS &  |          |                 |             |
|          | MISR gases & |          |                 |             |
|          | aerosols)    |          |                 |             |
+----------+--------------+----------+-----------------+-------------+
| CERES    | Radiances,   | 2        | 2               | 2           |
|          | Albedos,     |          |                 |             |
|          | Fluxes       |          |                 |             |
+----------+--------------+----------+-----------------+-------------+
| Earth    |              |          |                 |             |
| Probe    |              |          |                 |             |
+----------+--------------+----------+-----------------+-------------+
| TOMS     | Ozone column | 1        | 1               | 1           |
+----------+--------------+----------+-----------------+-------------+
|          | Aerosol      | 1        | 1               | 1           |
|          | index        |          |                 |             |
+----------+--------------+----------+-----------------+-------------+
| #        |              |          |                 |             |
| ADEOS II |              |          |                 |             |
+----------+--------------+----------+-----------------+-------------+
| POLDER   | Aerosol      | 1        | 1               | 1           |
|          | optical      |          |                 |             |
|          | depth        |          |                 |             |
|          | spectra &    |          |                 |             |
|          | R~eff~       |          |                 |             |
+----------+--------------+----------+-----------------+-------------+
| # Se     |              |          |                 |             |
| aStar, O |              |          |                 |             |
| rbView 2 |              |          |                 |             |
+----------+--------------+----------+-----------------+-------------+
| SeaWiFS  | Normalized   | 2        | 1               | 1           |
|          | w            |          |                 |             |
|          | ater-leaving |          |                 |             |
|          | radiance     |          |                 |             |
|          | (Atmos.      |          |                 |             |
|          | Corr.)       |          |                 |             |
+----------+--------------+----------+-----------------+-------------+