A Proposal to the Office of Naval Research

800 North Quincy Street

Arlington, VA 22217-5660

Attn: Dr. Ronald J. Ferek, Ph 703-696-0518, ferekr@onr.navy.mil

for

**Solar Spectral Flux, Optical Depth, and Water Vapor Measurements and
Analyses**

**in the Puerto Rico Dust Experiment (PRIDE)**

Co-Principal Investigators:

+-----------------------------------+-----------------------------------+
| Peter Pilewskie Date              | Philip B. Russell Date            |
|                                   |                                   |
| Atmospheric Physics Research      | Atmospheric Chemistry and         |
| Branch                            | Dynamics Branch                   |
|                                   |                                   |
| Earth System Science Division     | Earth System Science Division     |
|                                   |                                   |
| NASA Ames Research Center,        | NASA Ames Research Center,        |
| Moffett Field, CA 94035-1000      | Moffett Field, CA 94035-1000      |
|                                   |                                   |
| Telephone: 650-604-0746. Fax:     | Telephone: 650-604-5404. Fax:     |
| 650-604-3625                      | 650-604-6779                      |
|                                   |                                   |
| ppilewskie@mail.arc.nasa.gov      | prussell@mail.arc.nasa.gov        |
+-----------------------------------+-----------------------------------+

Co-Investigators:

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

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)

Research Period and Budget Requested from ONR:

[Task 1]{.underline} [Task 2]{.underline} [Total]{.underline}

June 1, 2000 - May 30, 2001: \$50.25K \$86.45K \$136.7K

Reviewed by:

+-----------------------------------+-----------------------------------+
| Warren J. Gore, Chief Date        | R. Stephen Hipskind, Chief Date   |
|                                   |                                   |
| Atmospheric Physics Research      | Atmospheric Chemistry and         |
| Branch                            | Dynamics Branch                   |
+-----------------------------------+-----------------------------------+

Authorizing Official:

Estelle P. Condon, Chief Date

Earth Science Division

NASA Ames Research Center

TABLE OF CONTENTS

[Page]{.underline}

ABSTRACT 1

1\. BACKGROUND 1

> 1.1 The Puerto Rico Dust Experiment (PRIDE) 1
>
> 1.2. Results From Previous Work 2
>
> 1.2.1 Solar Spectral Flux Radiometer (SSFR) Analysis and Results 2
>
> 1.2.2 Ames Airborne Tracking Sunphotometer (AATS) Analysis and Results
> 3

2\. PROPOSED RESEARCH 4

> 2.1 Objectives 4
>
> 2.2. Proposed Tasks 5
>
> 2.2.1 ONR-Funded Task One: SSFR Measurements and Analyses 5
>
> 2.2.2 ONR-Funded Task Two: AATS-6 Measurements and Analyses 5
>
> 2.2.3 NASA-Funded Integrated Analyses 5
>
> 2.3. Schedule 5
>
> 2.4. References 6

3\. BUDGET 7

4\. STAFFING, RESPONSIBILITIES, AND VITAE 7

ILLUSTRATIONS F1

ABSTRACT

We propose to provide measurements and analyses of solar spectral fluxes
and direct beam transmissions in support of the Puerto Rico Dust
Experiment (PRIDE). Spectral fluxes (300-1700 nm at 10 nm resolution)
will be measured by a zenith and nadir viewing Solar Spectral Flux
Radiometer (SSFR) on the SPAWAR Navajo and a zenith viewing ground-based
SSFR. Direct beam transmissions will be measured in 6 narrow bands
(380-1020 nm) by the 6-channel Ames Airborne Tracking Sunphotometer
(AATS-6) on the SPAWAR Navajo; they will be analyzed to derive aerosol
and thin-cloud optical depth at 5 wavelengths, plus column water vapor
overburden. The data will be used to determine the net solar radiative
forcing of dust (and other) aerosol, to quantify the solar spectral
radiative energy budget in the presence of elevated aerosol loading, to
support satellite algorithm validation, and to provide tests of closure
with in situ measurements.

**1 BACKGROUND**

**1.1 The Puerto Rico Dust Experiment (PRIDE)**

The Puerto Rico Dust Experiment (PRIDE) is a field study of the
radiative, microphysical, and transport properties of Saharan dust,
scheduled for July 2000 (Reid, 2000). A group of Navy, NASA, and
university scientists plan to conduct a combined surface, airborne,
satellite and modeling campaign out of the Roosevelt Roads Naval Base,
Puerto Rico in an effort to measure the properties of African dust
transported into the Caribbean. There will be two principal thrusts: 1)
Determine the extent to which the properties of dust particles and the
spectral surface reflectance of the ocean surface need to be known
before remote sensing systems can accurately determine optical depth and
flux. 2) Evaluate/validate the skill in which the Naval Research
Laboratory's Aerosol Analysis and Prediction System (NAAPS) predicts the
long-range transport and vertical distribution of African dust. The
results of these efforts will support Navy and NASA applied science
objectives on satellite validation and the prediction of dust-induced
visibility degradation. In addition, secondary thrusts of PRIDE will
address in situ issues of coarse mode particles and basic research
issues on climate forcing, geochemical cycles, and meteorology.

**1.2 Results From Previous Work**

**1.2.1 Solar Spectral Flux Radiometer (SSFR) Analysis and Results**

#### *Cloud Remote Sensing*

The SSFR is a newer version of a prototype spectroradiometer that was
first designed to infer the thermodynamic phase of clouds (Pilewskie and
Twomey, 1987; Pilewskie and Twomey, 1992). Using measurements of either
spectral reflectance or spectral transmission (defined by the observer's
viewing angle; for reflectance, /2; for transmission, 0/2), cloud phase
can be determined by the signal in the atmospheric window between 1.55 m
and 1.75 m. Since ice is nearly four times more absorbing than liquid
water at 1.65 m, ice spectra have lower amplitude signal in this band.
The ice spectrum also shows a shift of the peak signal towards longer
wavelength when compared to a water cloud spectrum, following the
absorption spectra of bulk liquid water and ice.

The result of applying asymptotic formulae to derive relationships
between measured transmission and the bulk absorption affords a simple
yet powerful constraint on the composition of absorbing material. These
relationships can be used not only to unambiguously discriminate between
cloud phase, but also to reveal the presence of a heretofore "unknown"
absorber. Our observations of near-infrared cloud transmission have
substantiated the premise that liquid water and ice are the dominant
absorbers in the near-infrared window bands. Similar relationships are
being employed to develop methods of inferring cloud ice/liquid water
content and enhanced water vapor path through the multiple scattering
medium of thick clouds (Pilewskie and Twomey, 1996).

# *Clear Sky Solar Radiative Energy Budget*

The first SSFR data to be extensively analyzed and compared to model
derived spectra for cloud-free conditions were obtained during the NASA
SUCCESS experiment in 1995. Comparisons between measurements and model
calculations of the spectrally resolved downwelling irradiance at the
ground showed that for cloud-free conditions there was agreement to
within instrumental and model uncertainties of 5% (Pilewskie, et al.,
1998). The greatest disagreement occurred in the 400 -700 nm band. The
integrated irradiance over the band from 400 nm to 2200 nm agreed to
within 3%. Roughly 85% of the difference between the modeled and
measured integrated irradiance occurred in the 400 to 700 nm band. The
level of agreement between measured and modeled spectra in the water
vapor absorption bands was encouraging, considering that water vapor is
the primary absorber in the atmosphere. However, we concluded that it
would be necessary to compare similar spectral data over a broader range
of atmospheric conditions to fully assess our ability to model solar
spectral irradiance.

Data acquired during the 1997 Department of Energy Atmospheric Radiation
Measurement (DOE ARM) Shortwave Intensive Operating Period (SWIOP) shows
that a discrepancy exists between models and observations in the cloud
free atmosphere and it is highly correlated with water vapor (Pilewskie
et al., 2000). The difference between modeled and measured flux
increases most rapidly in the two mid-visible bands between 442 nm and
778 nm and the trend becomes nearly flat in the near-infrared (see
Figure 1). Over this entire spectral region the difference grows at a
rate of approximately 9 Wm^-2^ per cm of water. Relative to the energy
at the top of the atmosphere, the bias increases by about 1% per cm of
water in the two bands between 442 and 625 nm and 625 and 778 nm, with
smaller relative contributions in the other bands. The source of the
discrepancy remains undetermined because of the complex dependencies of
other variables on water vapor.

## *Principal Component Analysis*

A formal approach to any remote sensing problem is to transform the
original set of measured variables into a smaller set of
mutually-orthogonal uncorrelated variables. For SSFR spectra, the
measurement variables are irradiance (or radiance) values at many
wavelengths. While several hundred measurements comprise a single
spectrum, relatively few are independent: measurement of flux at one
wavelength is sufficient to calculate flux in other regions of the
spectrum given constituents of known absorption and scattering. The
initial step is to determine the correlation between irradiance at
different wavelengths which is then used to derive the *principal
components*, linear combinations of the original irradiance values. The
virtue of this procedure is to define the minimum number of parameters
necessary to characterize atmospheric spectral irradiance, or the
*dimensionality* of atmospheric variability. PCA can be applied to set
limits on the number of parameters that can be inverted from a spectral
data set.

Physically independent influences (in our application, different
absorbers and scatterers: condensed water, oxygen, ozone, carbon
dioxide, aerosols, etc.) do not in general produce independent
orthogonal components in the measurement (spectral) domain. PCA produces
orthogonal patterns, which of necessity are weighted combinations of the
contributions of two or more independent influences. That difficulty
faces PCA in general and has been discussed at some depth by Richman
(1986), who describes so-called rotation schemes that affect a
recombination of raw orthogonal patterns to produce patterns
(non-orthogonal) that better separate effects of physically independent
causes.

This was the general procedure followed by Rabbette and Pilewskie (2000)
in the analysis of SSFR spectra from the ARM 1997 Fall Shortwave
Intensive Observation Period (SWIOP). The input variable matrix used in
that study constituted nearly 7000 spectra (between 360 and 1000 nm)
which were acquired over a three-week period at the ARM CART site in
north central Oklahoma. The time series of the first two rotated
Principal Components (PCs) reveal strong similarities to the time series
of cloud liquid water content (97% of the explained variance) and
integrated column water vapor (2.5% of explained variance). Since the
analyzed spectra were in the shortest wavelength region of the solar
spectrum, variability associated with cloud water was due to scattering,
not absorption.

# *The Solar Radiative Energy Budget in the Cloudy Atmosphere*

The solar radiative energy budget of cloud the cloudy atmosphere has
been the focus of considerable attention due to several recent studies
which suggested that our ability to estimate broadband radiative fluxes
and, consequently, to infer atmospheric absorption, using detailed
radiative transfer models is poor (Cess, et al., 1995; Pilewskie and
Valero, 1995; Valero et al., 1998). The recently completed Atmospheric
Radiation Measurement (Arm) Enhanced Shortwave Experiment (ARESE) was
the second major DOE field campaign dedicated to measuring the
absorption of solar radiation by clouds. Figure 2 is an example of SSFR
spectra during ARESEII and is representative of the type of data we will
obtain during the PRIDE flight missions. During ARESEII the SSFR was
integrated on the Sandia National Laboratory Twin Otter in nadir and
zenith viewing ports. The blue curve is the nadir-viewing (upwelling)
irradiance over north-central Oklahoma on 20 March 2000 at 1700 GMT.
Spectral integration time is 100 ms. The red curve is the zenith-viewing
(downwelling) irradiance, also at 1700 GMT, and the green spectrum is
the difference between downwelling and upwelling irradiance, or the net
flux. During ARESE II nearly 200,000 irradiance spectra were acquired
over a variety of scenes and altitudes in the lower and middle
troposphere.

**1.2.2 Ames Airborne Tracking Sunphotometer (AATS) Analysis and
Results**

The Ames Airborne Tracking Sunphotometers (AATS-6 and AATS-14) have
previously flown on a variety of aircraft to study a wide range of
aerosol and trace gas phenomena. Among the AATS results most relevant to
PRIDE are those obtained in the second Aerosol Characterization
Experiment (ACE-2), where elevated layers of Sahara dust were studied
over the eastern Atlantic Ocean (Russell and Heintzenberg, 2000). Figure
3 shows an example measured by AATS-14 on the Pelican aircraft in the
Canary Islands (Schmid et al., 2000). The optical depth profiles in the
left panel were smoothed and vertically differentiated to obtain the
extinction profiles in the right panel. The extinction profiles clearly
show the presence of three distinct layers: an elevated layer of Sahara
dust, a moderately polluted marine boundary layer, and an intervening
layer that is nearly aerosol-free. Note the marked difference in
extinction wavelength-dependence in the two aerosol layers: a strong
dependence in the boundary layer (extinction profiles separated in
wavelength) and almost no dependence in the elevated dust layer
(extinction profiles overlapping except at 1558 nm). This difference
reflects the difference of aerosol size in the two layers, with
accumulation-mode particles important in the polluted boundary layer and
coarse-mode particles more important in the Sahara layer.

Figure 4 shows how the presence of elevated dust layers can affect the
accuracy of optical depths retrieved from satellite radiance
measurements. The scatter diagram in Figure 4a (Durkee et al., 2000)
compares AVHRR-retrieved aerosol optical depth (AOD) at 630 and 860 nm
with AOD measured in ACE-2 by a variety of sunphotometers on land, ship,
and aircraft. Data points with AOD\>0.25 are cases where an elevated
layer of Sahara dust was present; those with AOD\<0.25 had no Sahara
dust. For all 23 cases shown the AVHRR standard error of estimate is
0.025 for 630 nm wavelength and 0.023 for 860 nm. Note that in the
dust-containing cases (AOD\>0.25), the AVHRR-retrieved AODs are biased
low compared to sunphotometer optical depths (by amounts ranging from
0.01 to 0.08). In contrast, for the dust-free cases AVHRR-retrieved
values are biased slightly high. Figure 4b compares AOD spectra for a
case from Figure 4a where dust was present (this is also the case from
Figure 3); Figure 4c is the analogous comparison for a dust-free case
(Livingston et al., 2000; Schmid et al., 2000). These cases show clearly
the change in bias of the AVHRR retrieved values between dust-free and
dust-containing cases, especially at 860 nm. Possible reasons for this
change 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., 2000), plus the height of
the absorbing dust aerosols (e.g., Quijano et al., 1999). In PRIDE,
sunphotometer underflights of aerosols in different conditions (e.g.,
marine aerosols with and without Sahara dust aloft) could provide
analogous tests of the validity of satellite products as a function of
condition. Vertical profile flights by the sunphotometer aircraft or a
coordinated aircraft could provide simultaneous in situ data on aerosol
physicochemical properties, helping to complete the picture.

In addition to vertical profile flights, airborne sunphotometer
measurements flown along horizontal transects near the land or ocean
surface can provide aerosol optical depth spectra useful for validating
products from simultaneous satellite overflights. This is illustrated in
Figure 5, which shows a comparison of airborne sunphotometer (AATS-6),
AVHRR, and ATSR-2 data acquired in TARFOX (Russell et al., 1999a) 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 5a and 5b shows that the ATSR-2
retrieval reproduces the sunphotometer-measured optical depth gradient
better than the AVHRR retrieval. Comparing 3c and 3d shows how the
ATSR-2 retrieval also matches the sunphotometer-determined Angstrom
exponent better than AVHRR. In PRIDE, GOES or other realtime satellite
imagery could be used to design flight legs across the gradient from
plume core to edge during a subsequent satellite overpass (by, e.g., EOS
Terra carrying MODIS, MISR, and CERES). AATS optical depth spectra on
legs flown near the surface would provide validation data for
comparisons such as those in Figure 5.

Figure 6 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 \<1 m) degraded when optical depth
decreased below \~0.05 (causing MAS-measured radiance from the aerosol
to decrease relative to radiance from the ocean surface). Establishing
such limits and uncertainties is a major reason for validation studies.
In PRIDE they could be conducted for a variety of aerosol types and
conditions, over different types of land surfaces (e.g., densely vs.
sparsely vegetated), glint-free and glinting swaths of ocean, and on
transects spanning land and ocean.

2 PROPOSED RESEARCH

**2.1 Objectives**

The objectives of the proposed research are to:

(1) Improve understanding of dust, other aerosol, and water vapor
    effects on radiative transfer, radiation budgets and climate in the
    Caribbean region, and

\(2\) Test and improve the ability of satellite remote sensors (such as
MODIS, MISR, CERES, TOMS, AVHRR) to measure these constituents and their
radiative effects.

**2.2 Proposed Tasks**

**2.2.1 ONR-Funded Task One: SSFR Measurements and Analyses**

The NASA Ames Radiation group will deploy a Solar Spectral Flux
Radiometer (SSFR) on the SPAWAR Navajo during the Puerto Rico Dust
Experiment (PRIDE) in June-July, 2000. The SSFR has zenith and nadir
viewing light collectors for measuring solar spectral upwelling and
downwelling irradiance from 300 to 1700 nm at 10 nm resolution. This
data will be used to determine the net solar radiative forcing of dust
(and other) aerosol, to quantify the solar spectral radiative energy
budget in the presence of elevated aerosol loading, and to support
satellite algorithm validation. We will attempt to deploy a zenith
viewing ground-based SSFR (for no additional cost to the project) at a
selected surface site.

The SSFR is calibrated for wavelength, absolute power, and angular
response at the NASA Ames Research Center. Some of this work is done in
conjunction with the Ames Airborne Sensors Facility which takes part in
round robin calibration comparisons with NIST and the University of
Arizona. The Airborne Sensors Facility is also responsible for
calibrating flight simulation sensors, such as the MODIS Airborne
Simulator (MAS), and the use of identical standards will allow us to
trace SSFR calibrations to MAS.

We will meet all data archival schedules; we anticipate three levels of
data release.

**2.2.2 ONR-Funded Task Two: AATS-6 Measurements and Analyses**

For the funding requested in this proposal (Section 3) the NASA Ames
Sunphotometer/Satellite group will perform the following subtasks: (a)
Integrate the 6-channel Ames Airborne Tracking Sunphotometer (AATS-6) on
the SPAWAR Navajo. (b) Calibrate AATS-6 before and after PRIDE. (c)
Provide continuous realtime measurements of aerosol and thin cloud
optical depth spectra and water vapor column contents during PRIDE
flights. (d) Use these data in flight direction and planning.

**2.2.3 NASA-Funded Integrated Analyses**

In addition to ONR funded Tasks One and Two, we plan to perform the
following subtasks using NASA funding: (e) Compare AATS-6 results to
those of the satellite sensors listed above (as, e.g., in Figures 4-6);
in cases of disagreement, investigate causes and retrieval algorithm
improvements. (f) For aircraft profiles derive profiles of aerosol
extinction spectra and water vapor density by differentiating optical
depth and column water vapor profiles (as exemplified by Figures 3 and
7). (g) Combine these data with those from the SSFR and conduct new
analyses of aerosol radiative forcing sensitivity, single scattering
albedo, and the solar spectral radiative energy budget (as exemplified
by Figure 8). (h) Derive aerosol size distributions from optical depth
and extinction spectra (as exemplified by Figure 9). (i) Combine data
with in situ measurements (e.g., the SPAWAR measurements of size
distribution, scattering, and/or absorption) to provide tests of closure
and integrated assessments of aerosol and trace gas radiative effects.
An example of such a closure test is shown in Figure 10 (Schmid et al.,
2000). Results of the analyses will be reported in joint publications
with collaborating investigators.

**2.3 Schedule**

6/00: Integration of SSFR and AATS-6 on SPAWAR Navajo

6/00: Final pre-flight SSFR and AATS-6 calibration

6-7/00: Field deployment

8-10/00: post-flight calibrations

11/00: first data release

3/01: second data release

6/01: final data release

**2.4 References**

Cess, R.D., et al., Absorption of solar radiation by the earth's
surface: Observations versus models. *Science*, **267**, 496 (1995).

Durkee, P. A., Nielsen, K. E., Russell, P. B., Schmid, B., Livingston,
J. M., Collins, D., Flagan, R. C., Seinfeld, H. H., Noone, K. J.,
Ostrom, E., Gassó, S., Hegg, D., Bates, T. S., Quinn, P. K., and
Russell, L. M. this issue. Regional aerosol properties from satellite
observation: ACE-1, TARFOX and ACE-2 results. *Tellus B* in press, 2000.

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 in press, 2000.

Pilewskie, P., M. Rabbette, 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.* **25**, 137 (2000).

Pilewskie, P. and S. Twomey, Cloud properties derived from surface-based
near-infrared spectral transmission**.** *IRS \'96: Current Problems in
Atmospheric Radiation*, A. Deepak Publishing, Fairbanks, Alaska (1996).

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

Pilewskie, P., and S. Twomey, Optical remote sensing of ice in clouds.
*J. of Wea. Modif.*, **24**, 80, (1992).

Pilewskie, P. and S. Twomey, Discrimination of ice from water in clouds
by optical remote sensing. *Atmos. Research*, **21**, 113 (1987).

Pilewskie, P., and S. Twomey, Cloud phase discrimination by reflectance
measurements near 1.6 and 2.2 m. *J. Atmos. Sci.*, **44**, 3419 (1987).

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.

Rabbette , M. and P. Pilewskie, Multivariate analysis of solar spectral
irradiance measurements. *J. Geophys. Res*. In press (2000).

Richman, M. B., 1986: Rotation of principal components. *J. Clim*,
**6**, 293-335.

Reid, J., Preliminary Mission Plan for a Puerto Rico Dust Experiment
(PRIDE) for Summer 2000. Available from the author, SPAWARSYSCEN SAN
DIEGO D883, 49170 Propagation Path, San Diego, CA 92152-7385, email:
<jreid@spawar.navy.mil>, http://www.spawar.navy.mil

Russell, P. B., and J. Heintzenberg, An overview of the ACE-2 Clear Sky
Column Closure Experiment (CLEARCOLUMN), *Tellus*, in press, 2000.

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.

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*
in press, 2000.

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.

Valero, F.P.J., R.D. Cess, M. Zhang, S.K. Pope, A. Bucholtz, B. Bush,
and J. Vitko, Jr., Absorption of solar radiation by the atmosphere:
interpretations of collocated aircraft measurements. *J. Geophys. Res*.,
**102**, 29,917-29,927 (1997).

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.

![](media/image1.pct)

**4. STAFFING, RESPONSIBILITIES, AND VITAE**

Drs. Peter Pilewskie and Philip B. Russell will be Co-Principal
Investigators. Dr. Pilewskie will be responsible for the SSFR
measurements and analyses; Dr. Russell will be responsible for the
AATS-6 measurements and analyses. Drs. Pilewskie and Russell will
collaborate on analyses that combine SSFR and AATS-6 measurements, as
well as on flight planning for such measurements. They will be
responsible for the completion of their tasks within budget and
schedule. Mr. John Livingston will have primary responsibility for
AATS-6 calibrations and airborne measurements. He and Dr. Beat Schmid
will participate in AATS-6 preparation, data analyses, and publications.
Dr. Jens Redemann will participate in selected calibrations and
analyses. Ames will furnish additional engineering and technical
personnel necessary to maintain, operate, and repair the instrumentation
before, during, and after the calibrations and field measurements.

**(a) Peter Pilewskie**

**Abbreviated Curriculum Vitae**

**Education:**

B.S., Meteorology, Pennsylvania State University, 1983

M.S., Atmospheric Science, University of Arizona, 1986

Ph.D., Atmospheric Science, University of Arizona, 1989

**Professional Experience:**

Radiation Group Leader, Atmospheric Physics Branch, NASA Ames Research
Center, 1994-present

Research Scientist, Atmospheric Physics Branch, NASA Ames Research
Center, 1989-1994

Research Assistant, Institute of Atmospheric Physics, University of
Arizona, 1983-1989

**Professional Activities:**

Member, Atmospheric Radiation Measurement (ARM) Enhanced Shortwave
Experiment (ARESE) II Science Team

Member, Solar Radiation and Climate Experiment (SORCE), 1999-present

Member, Triana Science Team, 1998-present

Member, Global Aerosol Climatology Program (GACP), 1998-present

Member, Atmospheric Radiation Measurement Program (ARM) Science Team,
1997-present

Member, International Global Atmospheric Chemistry (IGAC), Focus on
Atmospheric Aerosols, Direct Aerosol Radiative Forcing Activity,
1995-present

Member, First International Satellite Cloud Climatology Program (ISCCP)
Regional Experiment, Phase III (FIRE III) Science Team, 1994-present

# Science Team Leader, International Global Aerosol Program (IGAP), Radiative Effects of Aerosols, 1993

**Professional Honors:**

NASA Exceptional Scientific Achievement Medal, 1997

NASA Group Achievement Award, FIRE Phase II Science and Operations Team,
1997

NASA Ames Honor Award, Scientist, 1995

**Selected Publications:**

Pilewskie, P., M. Rabbette, 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.* **25**, 137(2000).

Rabbette , M. and P. Pilewskie, Multivariate analysis of solar spectral
irradiance measurements. *J. Geophys. Res*. In press (2000).

Curry, J.A., P.V. Hobbs, M.D. King, D.A. Randall, P. Minnis, G.A. Isaac,
J.O. Pinto, T. Uttal, A. Bucholtz, D.G. Cripe, H. Gerber, C.W. Fairall,
T.J. Garrett, J. Hudson, J.M. Intrieri, C. Jakob, T. Jensen, P. Lawson,
D. Marcotte, L. Nguyen, P. Pilewskie, A. Rangno, D.C. Rogers, K.B.
Strawbridge, F.P.J. Valero, A.G. Williams, and D. Wyliep, FIRE Arctic
Clouds Experiment, *Bulletin of the American Meteorological Society,*
**81**, 5 (2000).

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 (1998).

Heymsfield, J.A., G.M. McFarquhar, W.D. Collins, J.A. Goldstein, F.P.J.
Valero, W. Hart, and P. Pilewskie, Cloud properties leading to highly
reflective tropical cirrus: interpretations from CEPEX, TOGA COARE, and
Kwajalein, Marshall Islands, *J. Geophys. Res.*, **103**, 8805 (1998).

Valero, F.P.J., W. Collins , P. Pilewskie, A. Bucholtz, and P. Flatau,
Direct observations of the super greenhouse effect over the equatorial
Pacific, *Science,* **275***,* 1773 (1997).

Dong, X., T.P. Ackerman, E.E. Clothiaux, P. Pilewskie and Y. Han,
Microphysical and Radiative Properties of Boundary Layer Stratiform
Clouds Deduced from Ground-Based Measurements, *J. Geophy. Res*.,
**102**, 23829 (1997).

Pilewskie, P. and F.P.J. Valero, *Response to*: How much solar radiation
do clouds absorb?, *Science*, **271**, 1134 (1996).

Lubin, D., J.P. Chen, P. Pilewskie, V. Ramanathan, and F.P.J. Valero,
Microphysical examination of excess cloud absorption in the tropical
atmosphere, *J. Geophys. Res.*, **101**, 16961 (1996).

Westphal, D. L., S. Kinne, P. Pilewskie, J. M. Alvarez, P. Minnis, D.
F.Young, S. G. Benjamin, W. L. Eberhard, R. A. Kropfli, S. Y. Matrosov,
J. B. Snider, T. A. Uttal, A. J. Heymsfield, G. G. Mace, S. H. Melfi, D.
O\'C. Starr, and J. J. Soden, Initialization and validation of a
simulation of cirrus using FIRE-II data. *J. Atmos. Sci*., **53**, 3397
(1996).

Collins, W.D., F.P.J. Valero, P. Flatau, D. Lubin, H. Grassl, P.
Pilewskie, and J. Spinhirne, Radiative effects of convection in the
tropical Pacific, *Journal of Climate,* **101**, 14999 (1996).

Clarke, A.D., J.N. Porter, F.P.J. Valero, and P. Pilewskie, Vertical
profiles, aerosol microphysics and optical closure during ASTEX:
measured and modeled column optical properties, *J. Geophys. Res.*,
**101**, 4443 (1996)

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

Sokolik I.N., F.P.J. Valero, and P. Pilewskie, Spatial and temporal
variations of the radiative characteristics of the plume from the Kuwait
oil fires, submitted to *Biomass burning and Global Climate Change*,
Levine J.S., Ed., MIT Press, Cambridge, MA (1995)

Valero, F.P.J., S. Platnick, S. Kinne, P. Pilewskie, and A. Bucholtz,
Airborne brightness temperature measurements of the polar winter
troposphere as part of the Airborne Arctic Stratospheric Experiment II
and the effect of brightness temperature variations on the diabatic
heating in the lower stratosphere, *Geophys. Res. Lett.*, **20**, 2575
(1993).

Pilewskie, P., F.P.J. Valero, Optical depths and haze particle sizes
during AGASP III. *Atmos. Environment*, **27A**, 2895 (1993).

Russell, P.B., J.M. Livingston, E.G Dutton, R.F Pueschel, J.A. Reagan,
T.E DeFoor, M.A. Box, D. Allen, P. Pilewskie, B.M. Herman, S.A. Kinne,
and D.J. Hoffmann, 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**, 22969 (1993).

Valero, F.P.J. and P. Pilewskie, Latitudinal survey of spectral optical
depths of the Pinatubo volcanic cloud derived particle sizes, columnar
mass loadings, and effects on planetary albedo, *Geophys. Res. Lett.*,
**19,** 163 (1992).

Pilewskie, P., F.P.J. Valero, Radiative effects of the smoke from the
Kuwait oil fires. *J. Geophys. Res.*, **97**, 14541 (1992).

Pilewskie, P., and S. Twomey, Optical remote sensing of ice in clouds.
*J. of Wea. Modif.*, **24**, 80 (1992).

Pilewskie, P. and S. Twomey, Discrimination of ice from water in clouds
by optical remote sensing. *Atmos. Research*, **21**, 113 (1987).

Pilewskie, P., and S. Twomey, Cloud phase discrimination by reflectance
measurements near 1.6 and 2.2 m. *J. Atmos. Sci.*, **44**, 3419 (1987).

Reagan, J.A., P.A. Pilewskie, I.C. Scott-Fleming, and B.M. Herman,
Extrapolation of earth-based solar irradiance measurements to
exoatmospheric levels for broad-band and selected absorption-band
observations. *IEEE Trans. on Geosci. Remote Sensing*, **GE-25**, 647
(1987).

**(b) Philip B. Russell**

**Abbreviated Curriculum Vitae**

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, 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, Co-coordinator for the CLEARCOLUMN component of the Second
Aerosol Characterization Experiment (ACE-2) of the International Global
Atmospheric Chemistry (IGAC) Project. 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)

**SELECTED PUBLICATIONS**

**2000:**

Collins, D. R., et al. (with P. B. Russell), In situ aerosol size
distributions and clear column radiative closure during ACE-2. *Tellus
B*, in press, 2000.

Durkee, P. A., et al. (with P. B. Russell), Regional aerosol properties
from satellite observation: ACE-1, TARFOX and ACE-2 results. *Tellus B*,
in press, 2000.

Ferrare, R., et al. (with P. B. Russell), Comparisons of aerosol optical
properties and water vapor among ground and airborne lidars and sun
photometers during TARFOX, *J. Geophys. Res*., in press, 2000a.

Ferrare, R., et al. (with P. B. Russell), Comparisons of LASE, aircraft,
and satellite measurements of aerosol optical properties and water vapor
during TARFOX, *J. Geophys. Res*., in press, 2000b.

Gassó, S., et al. (with P. B. Russell), Influence of humidity on the
aerosol scattering coefficient and its effect on the upwelling radiance
during ACE-2. *Tellus B*, in press, 2000.

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), in press, 2000.

Ismail, S. , E.V. Browell, R. Ferrare, S. A. Kooi, M. Clayton, V.
Brackett, P.B. Russell, LASE measurement of aerosol and water vapor
profiles measured during TARFOX, *J. Geophys. Res.* (2^nd^ Special Issue
on TARFOX), in press, 2000.

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,* 27, 137-140, 2000.

Russell, P. B., and J. Heintzenberg, An overview of the ACE-2 Clear Sky
Column Closure Experiment (CLEARCOLUMN), *Tellus B*, in press, 2000.

Welton, E. J., et al. (with P. B. Russell), Ground-based lidar
measurements of aerosols during ACE-2: Instrument description, results,
and comparisons with other ground-based and airborne measurements.
*Tellus B*, in press, 2000.

\[See 2 *Tellus B* papers led by Livingston and Schmid in their CVs.\]

\[See 2 *J. Geophys. Res.* papers led by Redemann in his CV.\]

**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.

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.

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.

\[See *Geophys. Res. Lett.* paper led by Schmid in his CV.\]

**1998:**

Boucher, O. et al. (with P. B. Russell), Intercomparison of models
representing direct shortwave radiative forcing by sulfate aerosols, *J.
Geophys. Res., 103*, 16,979-16,998, 1998.

\[6 2-page peer-reviewed extended abstracts in *J. Aerosol. Sci.*
describing TARFOX and ACE-2 results.\]

**1997:**

Hamill, P., E. J. Jensen, P. B. Russell, and J. J. Bauman, \"The Life
Cycle of Stratospheric Aerosol Particles\", *Bull. Am. Meteor. Soc.*,
*78*, 1395-1410, 1997.

Hansen, J., et al. (with P. Russell), "Forcings and Chaos in Interannual
to Decadal Climate Change." *J. Geophys. Res. 102*, 25,679-25,720, 1997.

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.

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.

**Five Other Relevant Papers:**

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,
1996.

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., 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.

**(c) John Livingston**

**Abbreviated Curriculum Vitae**

Senior Research Meteorologist, Applied Physical Sciences Laboratory,

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 ground-based, airborne, and shipboard
> sunphotometer measurements
>
> Validation of satellite particulate extinction measurements (SAM II,
> SAGE I, and SAGE II), and corresponding studies of the global
> distribution of stratospheric aerosols
>
> Analysis of *in situ* measurements of stratospheric and tropospheric
> aerosols
>
> Acquisition, 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

Professional Experience

> Research Meteorologist to Senior Research Meteorologist, SRI
> International (1978-present)
>
> Research assistant, University of Arizona Institute of Atmospheric
> Physics (1974-1977)
>
> NASA Kennedy Space Center (1975-1976): participant in thunderstorm
> electrification studies

Academic Background

> University of Notre Dame Year-in-Japan Program (1971-1972), Sophia
> University, Tokyo, Japan
>
> B.S. summa cum laude in earth sciences (1974), University of Notre
> Dame, Notre Dame, IN
>
> M.S. in atmospheric sciences (1977), University of Arizona, Tucson, AZ
>
> M.B.A. with highest honors (1992), Santa Clara University, Santa
> Clara, CA

Honors

> NASA Ames Research Center Contractor of the Year (1997), NASA
> Certificate of Recognition (1992) for co-authored technical paper,
> NASA Group Achievement Award (1989) for Airborne Antarctic Ozone
> Experiment

Professional Associations

> American Geophysical Union

**PUBLICATIONS**

**2000:**

Collins, D. R., et al. (with J. M. Livingston), In situ aerosol size
distributions and clear column radiative closure during ACE-2. *Tellus
B*, in press, 2000.

Durkee, P. A., et al. (with J. M. Livingston), Regional aerosol
properties from satellite observation: ACE-1, TARFOX and ACE-2 results.
*Tellus B*, in press, 2000.

Ferrare, R., et al. (with J. M. Livingston), Comparisons of aerosol
optical properties and water vapor among ground and airborne lidars and
sun photometers during TARFOX, *J. Geophys. Res*., in press, 2000a.

Ferrare, R., et al. (with J. M. Livingston), Comparisons of LASE,
aircraft, and satellite measurements of aerosol optical properties and
water vapor during TARFOX, *J. Geophys. Res*., in press, 2000b.

Gassó, S., et al. (with J. M. Livingston), Influence of humidity on the
aerosol scattering coefficient and its effect on the upwelling radiance
during ACE-2. *Tellus B*, in press, 2000.

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), in press, 2000.

> Livingston, J. M., V. N. Kapustin, B. Schmid, P. B. Russell, P. K.
> Quinn, T. S. Bates, P. A. Durkee, P. J. Smith, V. Freudenthaler, M.
> Wiegner, D. S. Covert, S. Gassó, D. Hegg, D. R. Collins, R. C. Flagan,
> J. H. Seinfeld, V. Vitale and C. Tomasi, Shipboard sunphotometer
> measurements of aerosol optical depth spectra and columnar water vapor
> during ACE-2 and comparison with selected land, ship, aircraft, and
> satellite measurements. *Tellus B*, in press, 2000.

Redemann, J., et al. (with J. M. Livingston), Retrieving the Vertical
Structure of the Aerosol Complex Index of Refraction From Aerosol In
Situ and Remote Sensing Methods During TARFOX. *J. Geophys. Res*. 2^nd^
TARFOX special issue, in press, 2000.

Schmid, B., et al. (with J. M. Livingston), 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 B*, in press, 2000.

Welton, E. J., et al. (with J. M. Livingston), Ground-based lidar
measurements of aerosols during ACE-2: Instrument description, results,
and comparisons with other ground-based and airborne measurements.
*Tellus B*, in press, 2000.

**1999:**

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, 1999.

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.

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.

Schmid, B., J. Michalsky, R. Halthore, M. Beauharnois, L. Harrison, J.
Livingston, P.. Russell, B. Holben, T. Eck, and A. Smirnov, Comparison
of aerosol optical depth from four solar radiometers during the Fall
1997 ARM Intensive Observation Period, *Geophys. Res*. *Lett*., *104*,
2261-2278, 1999.

**1998:**

\[6 2-page peer-reviewed extended abstracts in *J. Aerosol. Sci.*
describing TARFOX and ACE-2 results.\]

**1997:**

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.

**Five Other Relevant Papers:**

Livingston, J.M., and P. B. Russell, Retrieval of aerosol size
distribution moments from multiwavelength particulate extinction
measurements. *J. Geophys. Res.*, *94*, 8425-8433, 1989.

Pueschel, R.F., J. M. Livingston, G. V. Ferry, and T. E. DeFelice,
Aerosol abundances and optical characteristics in the Pacific basin free
troposphere. *Atmos. Envir.*, *28*, 951-960, 1993.

Pueschel, R.F., J. M. Livingston, P. B. Russell, and S. Verma, Physical
and optical prop­erties of the Pinatubo volcanic aerosol: aircraft
observations with impactors and a Sun-tracking photometer. *J. Geophys.
Res.*, *99*, 12,915-12,922, 1994.

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,
1996.

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.

**(d) Beat Schmid**

**Abbreviated Curriculum Vitae**

### Bay Area Environmental Research Institute

3430 Noriega Street

San Francisco, CA 94122

# Education

  -------------------- --------- ------ -------------------------------------------
  M.S. (Lizentiat)               1991   Institute of Applied Physics, University of
                                        Bern, Switzerland

  Ph.D.                          1995   Institute of Applied Physics, University of
                                        Bern, Switzerland

  Postdoctoral         1995-97          Institute of Applied Physics, University of
  Fellowship                            Bern, Switzerland
  -------------------- --------- ------ -------------------------------------------

# Professional Experience

[Bay Area Environmental Research Institute]{.underline}, San Francisco,
CA (1997-Present)

-Senior Research Scientist

[University of Arizona]{.underline}, Tucson, AZ (Oct. 1995 -Jan. 1996)

-Visiting Scientist

::: Definition-Term
[University of Bern]{.underline}, Switzerland (1989-1997)
:::

-Research Assistant (1989-1995)

-Postdoctoral Researcher (1995-1997)

# Scientific Contributions

-   7 years of leading studies in ground-based and airborne sun
    photometry: instrument design and calibration, development and
    validation of algorithms to retrieve aerosol optical depth and size
    distribution, H~2~O and O~3~.

-   Participate with the NASA Ames Airborne Sun photometers in ACE-2
    (North Atlantic Regional Aerosol Characterization Experiment, 1997,
    Tenerife). Extensive comparison of results (closure studies) with
    other techniques: lidar, optical particle counters, nephelometers,
    and satellites.

-   Participate with the NASA Ames Airborne Sun photometers in the Dep.
    of Energy, Atmospheric Radiation Measurement (ARM) program
    integrated fall 1997 intensive observation period (IOP) in Oklahoma.
    Appointed to lead sun photometer intercomparison. Extensive
    comparison of water vapor results with radiosondes, microwave
    radiometers, lidar, and Global Positioning System.

-   Test of candidate methods for SAGE 3 satellite ozone/aerosol
    separation using airborne sunphotometer data.

-   Application of NOAA/AVHRR satellite data to monitor vegetation
    growth in Switzerland

# Scientific Societies/Committees

-American Geophysical Union

-American Meteorological Society

# Publications

**2000:**

**Schmid, B.,** J. M. Livingston, P. B. Russell, P. A. Durkee, H. H.
Jonsson, D. R. Collins, R. C. Flagan, J. H. Seinfeld, S. Gassó, D. A.
Hegg, E. Öström, K. J. Noone, E. J. Welton, K. J. Voss, H. R. Gordon, P.
Formenti, and M. O. Andreae, 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, in press, 2000.

Collins, D. R., Jonsson, H. H., Seinfeld, J. H., Flagan, R. C., Gassó,
S., Hegg, D. A., **Schmid, B**., Russell, P. B., Livingston, J. M.,
Öström, E., Noone, K. J., Russell, L. M. and Putaud, J. P. In situ
aerosol size distributions and clear column radiative closure during
ACE-2. Tellus, in press, 2000.

Durkee, P. A., Nielsen, K. E., Smith, P. J., Russell, P. B., **Schmid,
B**., Livingston, J. M., Holben, B. N., Collins, D. R., Flagan, R. C.,
Seinfeld, J. H., Noone, K. J., Öström, E., Gassó, S., Hegg, D., Russell,
L. M., Bates, T. S. and Quinn, P. K. Regional aerosol properties from
satellite observations: ACE-1, TARFOX and ACE-2 results. Tellus, in
press, 2000.

Gassó, S., Hegg, D. A., Noone, K. J., Covert, D. S., **Schmid, B.**,
Russell, P. B., Livingston, J. M., Durkee, P.A. and Jonsson, H. H.
Influence of humidity on the aerosol scattering coefficient and its
effect on the upwelling radiance during ACE2. Tellus, in press, 2000.

Livingston, J. M., V. Kapustin, **B. Schmid**, P. B. Russell, P. K.
Quinn, T. S. Bates, P. A. Durkee, P. J. Smith, V. Freudenthaler, D. S.
Covert, S. Gasso, D. Hegg, D. R. Collins, R. C. Flagan, J. H. Seinfeld,
V. Vitale, and C. Tomasi, Shipboard sunphotometer measurements of
aerosol optical depth spectra and columnar water vapor during ACE-2 and
comparison to selected land, ship, aircraft, and satellite measurements.
Tellus, in press, 2000.

Welton, E. J., Voss, K. J., Gordon, H. R., Maring, H., Smirnov, A.,
Holben, B. N., **Schmid, B.**, Livingston, J. M., Russell, P. B.,
Durkee, P. A., Formenti, P., Andreae, M. O. and Dubovik, O. Ground-based
lidar measurements of aerosols during ACE-2: lidar description, results,
and comparisons with other ground-based and airborne measurements.
Tellus, in press, 2000.

Redemann, J., R.P. Turco, K.N. Liou, P.B. Russell, R.W. Bergstrom, **B.
Schmid**, J.M. Livingston, P.V. Hobbs, W.S. Hartley, S. Ismail, R.A
Ferrare, E.V. Browell. Retrieving the Vertical Structure of the
Effective Aerosol Complex Index of Refraction From a Combination of
Aerosol In Situ and Remote Sensing Measurements During TARFOX. Journal
of Geophysical Research, in press, 2000.

Ferrare, R., S. Ismail, E. Browell, V. Brackett, M. Clayton, S. Kooi, 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. Journal of
Geophysical Research, in press, 2000.

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,* 27, 137-140, 2000.

**1999:**

**Schmid B.**, J. Michalsky, R. Halthore, M. Beauharnois, L. Harrison,
J. Livingston, P. Russell, B. Holben, T. Eck, and A. Smirnov, Comparison
of Aerosol Optical Depth from Four Solar Radiometers During the Fall
1997 ARM Intensive Observation Period, *Geophys. Res. Lett.*, Vol. 26,
No. 17, 2725-2728, 1999.

**1998:**

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

\[5 2-page peer-reviewed extended abstracts describing TARFOX and ACE-2
results in *J. Aerosol Sci.,* Vol. 29, Suppl. 1 and 2.\]

**1997:**

**Schmid, B.**, C. Mätzler, A. Heimo, and N. Kämpfer, 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, 1997.

**Two other relevant papers:**

**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, Vol. 101, No. D5,
9345-9358, 1996.

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

**(e) Jens Redemann**

**Abbreviated Curriculum Vitae**

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.

# 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.

# RELEVANT PUBLICATIONS

**2000:**

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 Effective Aerosol Complex Index of
Refraction From Aerosol In Situ and Remote Sensing Methods During
TARFOX, *[J. Geophys. Res.]{.underline}*, in press*.*

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, *[J. Geophys.
Res.]{.underline}*, in press*.*

**1999:**

Redemann, J., P.B. Russell, P. Hamill. Measurements and Modeling of
Aerosol Absorption and Single Scattering Albedo at Ambient Relative
Humidity, Presented at the AGU 1999 Fall Meeting, Dec. 13-17, San
Francisco, CA, 1999.

**1998:**

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.

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.

**Before 1997:**

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.

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.