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<tbody>
<tr class="odd">
<td colspan="5"><img src="media/image1.jpeg"
style="width:0.675in;height:0.58264in" /></td>
<td colspan="10"><p><u>Proposal Cover Page</u></p>
<p>Date: 4/15/2003</p></td>
<td colspan="4"><p>NRA-03-OES-02</p>
<p>Proposal Number:</p>
<p>(Leave blank for NASA use)</p></td>
</tr>
<tr class="even">
<td colspan="6">Name of Submitting Institution:</td>
<td colspan="7">Bay Area Environmental Research Institute</td>
<td colspan="4"><strong>Congressional District:</strong></td>
<td colspan="2">California #1</td>
</tr>
<tr class="odd">
<td><strong>Proposal Title:</strong></td>
<td colspan="18"><strong>Spatial variability of MODIS and MISR derived
atmospheric data products</strong></td>
</tr>
<tr class="even">
<td colspan="19"><p><strong><u>Certification of Compliance with
Applicable Executive Orders and US Code</u></strong></p>
<p>By submitting the proposal identified in this <em>Cover
Sheet/Proposal Summary</em> in response to this Research Announcement,
the Authorizing Official of the proposing institution (or the individual
proposer if there is no proposing institution) as identified below:</p>
<ul>
<li><p>certifies that the statements made in this proposal are true and
complete to the best of his/her knowledge;</p></li>
<li><p>agrees to accept the obligations to comply with NASA award terms
and conditions if an award is made as a result of this proposal;
and</p></li>
<li><p>confirms compliance with all provisions, rules, and stipulations
set forth in the two Certifications contained in this NRA [namely,
(i<em>) Assurance of Compliance with the NASA Regulations Pursuant to
Nondiscrimination in Federally Assisted Programs</em>, <em>and (ii)
Certifications, Disclosures, And Assurances Regarding Lobbying and
Debarment &amp; Suspension</em>]<em>.</em></p></li>
</ul>
<p>Willful provision of false information in this proposal and/or its
supporting documents, or in reports required under an ensuing award, is
a criminal offense (U.S. Code, Title 18, Section 1001).</p>
<p><strong><u>NASA PROCEDURE FOR HANDLING PROPOSALS</u></strong></p>
<p>This proposal shall be used and disclosed for evaluation purposes
only, and a copy of this Government notice shall be applied to any
reproduction or abstract thereof. Any authorized restrictive notices
that the submitter places on this proposal shall also be strictly
complied with. Disclosure of this proposal for any reason outside the
Government evaluation purposes shall be made only to the extent
authorized by the</p></td>
</tr>
<tr class="odd">
<td colspan="4"><strong>Principal Investigator Names:</strong></td>
<td colspan="6">Jens Redemann, Beat Schmid</td>
<td colspan="4"><strong>Authorized Institutional Official
Name:</strong></td>
<td colspan="5">Marion E. Williams</td>
</tr>
<tr class="even">
<td colspan="4"><strong>Organization:</strong></td>
<td colspan="6">Bay Area Environmental Research Institute (BAER)</td>
<td colspan="4"><strong>Organization:</strong></td>
<td colspan="5">Bay Area Environmental Research Institute</td>
</tr>
<tr class="odd">
<td colspan="4"><strong>Mailing Address:</strong></td>
<td colspan="6">NASA Ames Research Center</td>
<td colspan="4"><strong>Mailing Address</strong></td>
<td colspan="5">560 3<sup>rd</sup> St. West</td>
</tr>
<tr class="even">
<td colspan="4"></td>
<td colspan="6">MS 245-5</td>
<td colspan="4"></td>
<td colspan="5"></td>
</tr>
<tr class="odd">
<td colspan="4"><strong>City, State Zip:</strong></td>
<td colspan="6">Moffett Field, CA 94035-1000</td>
<td colspan="4"><strong>City, State Zip:</strong></td>
<td colspan="5">Sonoma, CA 95476-6502</td>
</tr>
<tr class="even">
<td colspan="4"><strong>Telephone Number:</strong></td>
<td colspan="6">(805) 658-2637</td>
<td colspan="4"><strong>Telephone Number:</strong></td>
<td colspan="5">707 938-9387</td>
</tr>
<tr class="odd">
<td colspan="4"><strong>Fax Number:</strong></td>
<td colspan="6">(805) 658-2637</td>
<td colspan="4"><strong>Fax Number:</strong></td>
<td colspan="5">707 938-3984</td>
</tr>
<tr class="even">
<td colspan="4"><strong>Email Address:</strong></td>
<td colspan="6"><p><a
href="mailto:jredemann@mail.arc.nasa.gov">jredemann@mail.arc.nasa.gov</a></p>
<p><a
href="mailto:bschmid@mail.arc.nasa.gov">bschmid@mail.arc.nasa.gov</a></p></td>
<td colspan="4"><strong>Email Address:</strong></td>
<td colspan="5"><u>williams@baeri.org</u></td>
</tr>
<tr class="odd">
<td colspan="4"><strong>Principal Investigator Signatures:</strong></td>
<td colspan="6"></td>
<td colspan="4"><strong>Authorized Institutional Official
Signature:</strong></td>
<td colspan="5"></td>
</tr>
<tr class="even">
<td colspan="4"><strong>Date:</strong></td>
<td colspan="6"></td>
<td colspan="4"><strong>Date:</strong></td>
<td colspan="5"></td>
</tr>
<tr class="odd">
<td colspan="9"><strong>Authorized Institutional Official
Name:</strong></td>
<td colspan="10">David L. Peterson</td>
</tr>
<tr class="even">
<td colspan="9"><strong>Organization:</strong></td>
<td colspan="10">NASA Ames Research Center</td>
</tr>
<tr class="odd">
<td colspan="9"><strong>Department</strong></td>
<td colspan="10">Earth Science Division</td>
</tr>
<tr class="even">
<td colspan="9"><strong>Mailing Address</strong></td>
<td colspan="10">MS 245-5</td>
</tr>
<tr class="odd">
<td colspan="9"><strong>City, State Zip:</strong></td>
<td colspan="10">Moffett Field, CA, 94035-1000</td>
</tr>
<tr class="even">
<td colspan="9"><strong>Telephone Number:</strong></td>
<td colspan="10">650 604-5899</td>
</tr>
<tr class="odd">
<td colspan="9"><strong>Fax Number:</strong></td>
<td colspan="10">650 604-3625</td>
</tr>
<tr class="even">
<td colspan="9"><strong>Email Address:</strong></td>
<td colspan="10"><a
href="mailto:David.L.Peterson@nasa.gov">David.L.Peterson@nasa.gov</a></td>
</tr>
<tr class="odd">
<td colspan="9"><strong>Authorized Institutional Official
Signature:</strong></td>
<td colspan="10"></td>
</tr>
<tr class="even">
<td colspan="9"></td>
<td colspan="10"><strong>Date:</strong></td>
</tr>
<tr class="odd">
<td colspan="19"><strong>Co-Investigator:</strong></td>
</tr>
<tr class="even">
<td colspan="3"><strong>Name</strong></td>
<td colspan="4"><strong>Telephone</strong></td>
<td colspan="5"><strong>Email</strong></td>
<td colspan="3"><strong>Institution</strong></td>
<td colspan="4"><strong>Address</strong></td>
</tr>
<tr class="odd">
<td colspan="3">Philip B. Russell</td>
<td colspan="4">650 604-5404</td>
<td colspan="5"><u>Philip.B.Russell@nasa.gov</u></td>
<td colspan="4">NASA Ames</td>
<td colspan="3">Moffett Field, CA 94035</td>
</tr>
<tr class="even">
<td colspan="2"><strong>Budget:</strong></td>
<td colspan="6"></td>
<td colspan="3"><strong>BAER</strong></td>
<td colspan="7"><strong>NASA Ames</strong></td>
<td><strong>Total</strong></td>
</tr>
<tr class="odd">
<td colspan="8">Year 1 (October 2003-September 2004):</td>
<td colspan="3">$00.0K</td>
<td colspan="7">$00.0K</td>
<td>$00.0K</td>
</tr>
<tr class="even">
<td colspan="8">Year 2 (October 2004-September 2005):</td>
<td colspan="3">$00.0K</td>
<td colspan="7">$00.0K</td>
<td>$00.0K</td>
</tr>
<tr class="odd">
<td colspan="8">Year 3 (October 2005-September 2006):</td>
<td colspan="3">$00.0K</td>
<td colspan="7">$00.0K</td>
<td>$00.0K</td>
</tr>
<tr class="even">
<td colspan="8"><strong>Total:</strong></td>
<td colspan="3"><strong>$</strong>00.0<strong>K</strong></td>
<td colspan="7"><strong>$</strong>00.0<strong>K</strong></td>
<td><strong>$</strong>00.0<strong>K</strong></td>
</tr>
</tbody>
</table>

**TABLE OF CONTENTS**

[ACRONYMS iii](#acronyms)

[1 ABSTRACT / EXECUTIVE SUMMARY 1](#abstract-executive-summary)

[2 BACKGROUND AND RATIONALE 2](#background-and-rationale)

[2.1 MODIS aerosol retrievals over land
2](#modis-aerosol-retrievals-over-land)

[2.2 MODIS aerosol retrievals over ocean
2](#modis-aerosol-retrievals-over-ocean)

[2.3 Suborbital Measurements of AOD using AATS
3](#suborbital-measurements-of-aod-using-aats)

[3 PREVIOUS RESEARCH RELEVANT TO THIS PROPOSAL
4](#previous-research-relevant-to-this-proposal)

[3.1 Scientific Motivation 4](#scientific-motivation)

[3.2 Suborbital Measurements of aerosol optical depth on a moving
platform
6](#suborbital-measurements-of-aerosol-optical-depth-on-a-moving-platform)

[3.3 Measurements of aerosol optical depth in the vicinity of clouds
7](#measurements-of-aerosol-optical-depth-in-the-vicinity-of-clouds)

[4 SUMMARY OF PLANNED ACTIVITIES AS MODIS SCIENCE TEAM MEMBERS
9](#summary-of-planned-activities-as-modis-science-team-members)

[5 REFERENCES 11](#references)

[6 MANAGEMENT PLAN 13](#management-plan)

[6.1 Roles of Co-PI's and Co-I 13](#roles-of-co-pis-and-co-i)

[7 CURRENT SUPPORT OF PI's (B. Schmid/J. Redemann)
13](#current-support-of-pis-b.-schmidj.-redemann)

[8 BUDGET 14](#budget)

[8.1 General Budget 14](#general-budget)

[8.2 Travel budget 15](#travel-budget)

[9 VITAE 16](#vitae)

# ACRONYMS {#acronyms .unnumbered}

  -------------------- --------------------------------------------------
  AATS                 Ames Airborne Tracking Sunphotometer(s)

  ACE                  Aerosol Characterization Experiment

  ADAM                 Asian Dust and Aerosols above Monterey

  AERONET              Aerosol Robotic Network

  AOD                  Aerosol Optical Depth

  ARM                  Atmospheric Radiation Measurement

  AVHRR                Advanced Very High Resolution Radiometer

  AVIRIS               Airborne Visible Infrared Imaging Spectrometer

  CALIPSO              Cloud-Aerosol Lidar and Infrared Pathfinder
                       Satellite Observations

  CIRPAS               Center for Interdisciplinary Remotely Piloted
                       Aircraft Studies

  CERES                Clouds and the Earth\'s Radiant Energy System

  CLAMS                Chesapeake Lighthouse & Aircraft Measurements for
                       Satellites

  CWV                  Columnar Water Vapor

  DOE                  Department of Energy

  EOS                  Earth Observation System

  HIS                  High-resolution Interferometer Sounder

  IGAC                 International Global Atmospheric Chemistry

  IOP                  Intensive Observation Period

  MAS                  MODIS Airborne Simulator

  MASTER               MODIS/ASTER Airborne Sensors

  MISR                 Multi-Angle Imaging Spectroradiometer

  MODIS                Moderate-resolution Imaging Spectroradiometer

  OMI                  Ozone Monitoring Instrument

  POLDER               Polarization and Directionality of the Earth's
                       Reflectances

  PRIDE                Puerto Rico Dust Experiment

  PSAP                 Particle Soot Absorption Photometer

  PW                   Precipitable Water

  SAFARI               Southern African Regional Science Initiative

  SGP                  Southern Great Plains

  TARFOX               Tropospheric Aerosol Radiative Forcing
                       Observational Experiment

  TOMS                 Total Ozone Mapping Spectrometer

  UV                   Ultraviolet

                       

                       

                       

                       

                       

                       

                       

                       

                       

                       

                       

                       

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

#  {#section .unnumbered}

# ABSTRACT / EXECUTIVE SUMMARY

We propose the combined analysis of suborbital and EOS satellite
measurements of aerosol optical depth and columnar water vapor collected
during recent field experiments, with the intent of joining the
MODIS-Atmosphere Science Team. The proposed work is aimed at
investigating the spatial variability in MODIS- and MISR-derived data
products and assessing how well this variability is captured by
satellite sensors and their data products. In particular, the goals of
our study are:

1)  based on the combination of suborbital and satellite measurements,
    to determine the spatial variability of aerosol optical depth in the
    vicinity of clouds and assess how well current EOS satellite sensors
    capture or suppress such variability within their processing
    algorithms,

2)  to determine what fraction of the direct aerosol radiative forcing
    of climate may be undetected because the aerosol optical depth in
    the vicinity of clouds is erroneously filtered out or masked as
    cloud by current EOS sensor retrievals,

3)  to compare the spatial variability in aerosol optical depth and
    columnar water vapor in different geographical regions, thereby
    assessing the performance of current EOS sensor algorithms under a
    variety of regional and climatic conditions,

4)  to make available the validation capabilities of the NASA Ames
    Airborne Sunphotometer group to the MODIS-Atmosphere science team in
    support of future refinements to AOD and water vapor algorithms and
    future developments of over-the-ocean (glint/off-glint) algorithms
    to derive aerosol absorption.

Measurements taken by the NASA Ames Airborne Tracking Sunphotometers
(AATS-6 and AATS-14) in recent field campaigns have been used
extensively in the validation of satellite sensors aboard the EOS Terra
and other platforms, providing important aerosol information used in the
revision of retrieval algorithms for the MISR and MODIS sensors.

To date, little use has been made of the AATS instruments' unique
capabilities of measuring the spatial variability of aerosol optical
depth and water vapor on scales of a few hundred meters. Such spatial
variability can only be assessed from suborbital platforms that move
fast by comparison to wind advection speeds, and the AATS instruments
are currently the only sensors that can provide AOD measurements on
these scales. Small scale AATS measurements have frequently revealed the
presence of significant aerosol fields in the direct vicinity of clouds,
a phenomenon termed "cloud-halo" by the in situ measurement community.
These spatial scales are also comparable to the scales at which the EOS
satellite sensors apply cloud masking for the purpose of aerosol
retrievals. Therefore we propose to study the aerosol variability in the
vicinity of clouds and try to estimate what fraction of the direct
aerosol radiative forcing may be screened out by the current operational
cloud masking procedures for the MODIS and MISR aerosol algorithms. This
approach is directly aimed at answering the ESE questions about Earth's
natural variability (ESE strategic question 1) and how this variability
is captured by EOS sensors. Further, because aerosols are one of the
major climate forcing agents, the aerosol variability work is also aimed
at determining how well EOS sensors measure the primary forcings of the
Earth system (ESE strategic question 2).

Because of our experience in the combined analysis of suborbital and
satellite data and our previous work on the interpretation of MODIS and
MISR aerosol products, we feel uniquely qualified to carry out the
spatial variability assessment work proposed here.

# BACKGROUND AND RATIONALE 

A major uncertainty in predicting possible future changes to the Earth
system in general, and its climate in particular, stems from the
necessary inclusion of atmospheric aerosols in climate models. The
current low confidence in the estimates of aerosol induced perturbations
of Earth's radiation balance is caused by the highly non-uniform
compositional, spatial and temporal distribution of tropospheric
aerosols owing to their heterogeneous sources and short lifetimes.
Because of their short lifetimes, aerosols are most conveniently studied
using space-borne satellite sensors \[*Kaufman et al.*, 2002;
*Ramanathan et al*., 2002\]. Among the sensors that have provided global
aerosol information in the past are AVHRR and TOMS, which were not
optimized for the detection of aerosols. With the launch of the EOS
Terra satellite in 1999, a new era of satellite-based observations of
aerosols has begun. The MODIS \[*Kaufman et al*., 1997\] and MISR
\[*Kahn et al*., 2001, *Martonchik et al*., 1998\] instruments aboard
the Terra satellite as well as the MODIS instrument aboard the Aqua
satellite are much more capable of detailed global aerosol observations.
In the case of the MODIS instrument for example, the advantages of the
new sensor include its improved spectral coverage, narrower bandwidth of
the individual channels and improved spatial resolution of 500m (and
250m for some channels, as compared to 1km or 4km for AVHRR and 50km for
TOMS). In particular, the improved spatial resolution of the new sensors
allows for a better masking of clouds and hence an improved separation
of aerosols from clouds. Because a major part of this proposal is aimed
at investigating MODIS' capabilities of representing aerosol spatial
variability and separating aerosols from clouds, the following sections
briefly describe the MODIS aerosol retrieval algorithm.

## MODIS aerosol retrievals over land

The MODIS aerosol retrieval algorithm for measurements taken over land
is considerably different from the over-ocean algorithm \[*Kaufman et
al*., 1997\]. The first step in converting the satellite-measured
radiances into AOD is to organize the measured radiances of the three
MODIS channels at 0.47, 0.66 and 2.1µm into nominal 10 km boxes
corresponding to 20 by 20 or 400 pixels for each box. The 400 pixels in
the box are then evaluated to determine if the standard MODIS cloud mask
(MODIS product MOD35) has identified pixels as cloudy, as snow/ice or as
water. If the Normalized Difference Vegetation Index (NDVI) of a given
pixel is above a certain threshold level and the surface reflectance in
the 2.13µm channel is between 1 and 25% the pixel is considered suitable
for aerosol retrieval. After cloud masking and dark target selection the
pixels are sorted in terms of their visible reflectance at 0.66µm. The
darkest 20% and the brightest 50% of all pixels (at 0.66µm) are
discarded to eliminate remaining pixels possibly contaminated by cloud
shadows or odd surfaces at the dark end or residual cloud contamination
and odd surfaces at the bright end. The possibility of residual bright
cloud contamination is more common than cloud shadows, thus the filter
is skewed towards permitting more dark pixels than bright ones \[L.
Remer, private communication\]. The remaining 30% of the pixels will be
used to derive a mean reflectance for the 10 km box, but only if there
are at least 12 of the 400 pixels remaining. In the next step, the mean
measured reflectance is calculated from these 12 or more dark target
pixels in the three wavelengths. After surface reflectances have been
subtracted, the estimated surface reflectances and the measured mean
top-of-atmosphere reflectances at 0.47 and 0.66µm are used as input into
the Continental model Look-Up Table (LUT) to retrieve values for the
aerosol optical thickness at those two wavelengths.

## MODIS aerosol retrievals over ocean

The mechanics of the ocean algorithm are similar to the land algorithm
\[*Tanré et al*., 1997\], but channels used and other features are quite
different. In the first step, the reflectances from the six channels at
0.55, 0.66, 0.86, 1.24, 1.6 and 2.13 µm are grouped into nominal 10km
boxes of 20 by 20 pixels at 500 m resolution. The standard MOD35 cloud
mask includes using the brightness in the visible channels to identify
clouds. This procedure will mistake heavy aerosol as \'cloudy\', and
miss retrieving important aerosol events over ocean. On the other hand,
relying on IR-tests alone permits low altitude, warm clouds to be
misidentified as \'clear\', introducing cloud contamination in the
aerosol products. Thus, the cloud mask used in the aerosol retrieval
algorithm is based on the difference in spatial variability between
aerosols and clouds. It computes the standard deviation of 0.55µm
reflectances in every group of 3 by 3 pixels within a box. Any group of
9 contiguous pixels with standard deviation greater than 0.0025 is
labeled as \'cloudy\', and all 9 pixels in the group are discarded
\[Martins et al., 2002\]. This test separates aerosol from most cloud
types, but may fail at the centers of large, thick clouds and with
cirrus, both of which can be spatially homogeneous. It may also
erroneously identify inhomogeneous aerosol fields (e.g., dust) as
clouds. In an effort to avoid both scenarios, additional spectral
dependence filters are applied.

## Suborbital Measurements of AOD using AATS

From the previous two sections it is apparent that both the MODIS ocean
and land aerosol retrieval algorithms are dependent on the spatial
variability of aerosol fields in order to detect/mask cloudy pixels. In
the case of the land algorithm the standard MODIS cloud mask may discard
pixels that contain increased aerosol optical depth in the immediate
vicinity of clouds (less than 500m). Also, the aerosol retrieval
algorithm will discard those pixel which have sufficient cloud
contamination to place them in the upper 50% in terms of their
reflectance at 0.66µm. In the case of the ocean algorithm, cloud masking
is based solely on the spatial variability of the reflectance at 0.55µm.
Hence, suborbital measurements of the actual spatial variability of
aerosol optical depth and tests of the impact of that variability on
satellite radiances are crucial in assessing the adequacy of the cloud
screening procedures of either algorithm.

The only instruments currently capable of characterizing the spatial
variability of aerosol optical depth and column water vapor on scales of
a few hundred meters are the NASA Ames Airborne Tracking Sunphotometers
(AATS-6 and AATS-14). Both AATS instruments measure direct solar beam
transmission in narrow channels by using detectors in a tracking head
that rotates in two axes. Azimuth and elevation motors controlled by
differential sun sensors rotate the tracking head ,thereby locking on to
the solar beam and keeping detectors normal to it. The tracking head of
each instrument mounts external to the aircraft skin, to minimize
blockage by aircraft structures and also to avoid data contamination by
aircraft-window effects. The data yield AOD spectra and column water
vapor. Vertical differentiation of these data in suitable flight
patterns yields extinction spectra and water vapor concentration.
Examples are given in *Russell et al*., 1999, *Schmid et al*., 2000,
*Livingston et al*., 2002, *Schmid et al.*, 2002, *Redemann et al*.,
2002.

Spatial variability on the scale of a few hundred meters can only be
assessed from suborbital platforms that move fast by comparison to wind
advection speeds and only with instruments that provide data at rates of
a few Hz (1 Hz being equivalent to a spatial resolution of \~103m at an
aircraft speed of 200 knots). Because the AATS instruments measure the
direct solar beam transmission and are hence unaffected by surface
properties and because they are deployed on relatively fast-moving
suborbital platforms they are the only feasible tool for suborbital
studies of the spatial variability of aerosol optical depth. The
following section provides brief examples of AATS measurements and how
they may be exploited for the assessment of the performance of EOS
aerosol sensors.

# PREVIOUS RESEARCH RELEVANT TO THIS PROPOSAL

## Scientific Motivation

The deployments of AATS-6 and AATS-14 in previous field campaigns have
made significant contributions to the airborne study of atmospheric
aerosols. Most notably, the AATS-derived measurements of aerosol optical
depth in the Southern African Regional Science Initiative (SAFARI-2000),
the Puerto Rico Dust Experiment (PRiDE, 2000), the Asian-Pacific Aerosol
Characterization Experiment (ACE-Asia, 2001), and the Chesapeake
Lighthouse & Aircraft Measurements for Satellites (CLAMS, 2001) have
been used extensively in the validation of satellite sensors aboard the
NASA EOS Terra platform, providing important aerosol information used in
the revision of retrieval algorithms for the MISR \[*Kahn et al*., 2001,
*Martonchik et al*., 1998\] and MODIS sensors \[*Martins et al*., 2002,
*Levy et a*l., 2003\].

Figure 1 shows schematically the scientific motivation and overall
approach used in the AATS team's research. As indicated by Figure 1,
aerosols produced by biomass burning, desert dust storms, urban
pollution, and other processes form features recognizable from space on
regional to intercontinental scales \[e.g., *Husar et al*., 1997;
*Kaufman et al*., 2002; *Prospero et al*., 2002\]. These aerosols can
change the climate by perturbing energy exchange between the sun, Earth,
and space, as well as by redistributing energy within the atmosphere.

![](media/image2.wmf){width="6.0in" height="3.5375in"}

**Figure 1**. Schematic of the scientific motivation and overall
approach used in the AATS team's research.

To date, little use has been made of the AATS instruments' unique
capabilities of measuring aerosol optical depth and water vapor on
spatial scales of a few hundred meters. These small scale measurements
have frequently revealed the presence of significant aerosol fields in
the direct vicinity of clouds, a phenomenon termed "cloud-halo" in the
in situ measurement community.

Table 1 summarizes satellite validation studies that have used an AATS
instrument. To date, seven published studies have compared AATS
measurements to retrievals by MODIS or MISR aboard the EOS Terra
satellite.

*Table 1: Validation of satellite derived spectral AOD published by the
PI's and Co-I of this proposal.*

+-------+---------+---------+----------+---------+-------------------+
| **Sen | **Cam   | **R     | **S      | **P     | **Publication**   |
| sor** | paign** | egion** | urface** | eriod** |                   |
+-------+---------+---------+----------+---------+-------------------+
| AVHRR | TARFOX  | US East | Ocean    | July    | Veefkind et al.,  |
|       |         | Coast   |          | 1996    | 1999              |
+-------+---------+---------+----------+---------+-------------------+
| AVHRR | ACE 2   | Canary  | Ocean    | Ju      | Durkee et al.,    |
|       |         | Islands |          | ne/July | 2000              |
|       |         |         |          | 1997    |                   |
|       |         |         |          |         | Livingston et     |
|       |         |         |          |         | al., 2000         |
|       |         |         |          |         |                   |
|       |         |         |          |         | Schmid et al.,    |
|       |         |         |          |         | 2000              |
+-------+---------+---------+----------+---------+-------------------+
| A     | TARFOX  | US East | Ocean    | July    | Veefkind et al.,  |
| TSR-2 |         | Coast   |          | 1996    | 1999              |
+-------+---------+---------+----------+---------+-------------------+
| A     | SAFARI  | N       | Ocean    | Se      | Schmid et al.,    |
| TSR-2 | 2000    | amibian |          | ptember | 2003              |
|       |         | Coast   |          | 2000    |                   |
+-------+---------+---------+----------+---------+-------------------+
| GMS-5 | A       | Eastern | Ocean    | April   | Wang et al, 2003b |
|       | CE-Asia | Asia    |          | 2001    |                   |
+-------+---------+---------+----------+---------+-------------------+
| G     | PRIDE   | Puerto  | Ocean    | Ju      | Livingston et     |
| OES-8 |         | Rico    |          | ne/July | al., 2003         |
|       |         |         |          | 2000    |                   |
|       |         |         |          |         | Wang et al.,      |
|       |         |         |          |         | 2003a             |
+-------+---------+---------+----------+---------+-------------------+
| MAS   | TARFOX  | US East | Ocean    | July    | Tanré et al. 1999 |
|       |         | Coast   |          | 1996    |                   |
+-------+---------+---------+----------+---------+-------------------+
| MISR  | SAFA    | S       | Ocean &  | Se      | Schmid et al.,    |
|       | RI-2000 | outhern | Land     | ptember | 2003              |
|       |         | Africa  |          | 2000    |                   |
+-------+---------+---------+----------+---------+-------------------+
| MISR  | A       | Eastern | Ocean    | April   | Kahn et al., 2003 |
|       | CE-Asia | Asia    |          | 2001    |                   |
+-------+---------+---------+----------+---------+-------------------+
| MISR  | CLAMS   | US East | Ocean    | July    | Redemann et al.,  |
|       |         | Coast   |          | /August | 2001              |
|       |         |         |          | 2001    |                   |
+-------+---------+---------+----------+---------+-------------------+
| MODIS | PRIDE   | Puerto  | Ocean    | Ju      | Livingston et     |
|       |         | Rico    |          | ne/July | al., 2003         |
|       |         |         |          | 2000    |                   |
|       |         |         |          |         | Levy et al., 2003 |
+-------+---------+---------+----------+---------+-------------------+
| MODIS | SAFA    | S       | Ocean &  | Se      | Schmid et al.,    |
|       | RI-2000 | outhern | Land     | ptember | 2003              |
|       |         | Africa  |          | 2000    |                   |
+-------+---------+---------+----------+---------+-------------------+
| MODIS | CLAMS   | US East | Ocean    | July    | Levy et al., 2002 |
|       |         | Coast   |          | /August |                   |
|       |         |         |          | 2001    |                   |
+-------+---------+---------+----------+---------+-------------------+
| MODIS | A       | Eastern | Ocean    | April   | Chu et al., in    |
|       | CE-Asia | Asia    |          | 2001    | prep.             |
+-------+---------+---------+----------+---------+-------------------+
| POAM  | SOLVE-2 | Arctic  | Ocean &  | Jan/Feb | in prep.          |
|       |         |         | Land     | 2003    |                   |
+-------+---------+---------+----------+---------+-------------------+
| SAGE  | SOLVE-2 | Arctic  | Ocean &  | Jan/Feb | in prep.          |
| 3     |         |         | Land     | 2003    |                   |
+-------+---------+---------+----------+---------+-------------------+
| Se    | A       | Eastern | Ocean    | April   | Hsu et al, in     |
| aWiFS | CE-Asia | Asia    |          | 2001    | prep.             |
+-------+---------+---------+----------+---------+-------------------+
| TOMS  | PRIDE   | Puerto  | Ocean    | Ju      | Livingston et     |
|       |         | Rico    |          | ne/July | al., 2003         |
|       |         |         |          | 2000    |                   |
+-------+---------+---------+----------+---------+-------------------+
| TOMS  | SAFA    | S       | Land     | Se      | Schmid et al.,    |
|       | RI-2000 | outhern |          | ptember | 2003              |
|       |         | Africa  |          | 2000    |                   |
+-------+---------+---------+----------+---------+-------------------+

## Suborbital Measurements of aerosol optical depth on a moving platform

As indicated in Table 1 the NASA Ames Airborne Tracking Sunphotometers
have participated in 7 major field campaigns since 1996. In its most
recently completed deployment to study tropospheric aerosols, AATS-14
flew successfully aboard the University of Washington CV-580 research
aircraft during 10 research flights (45.09 flight hours) as part of the
Chesapeake Lighthouse and Aircraft Measurements for Satellites (CLAMS)
experiment, July 10 - August 2, 2001. The CLAMS campaign was a clear
sky, shortwave (SW) closure campaign and entailed measurements from the
Chesapeake Lighthouse research platform, several land sites, 6 research
aircraft and the EOS Terra satellite. CLAMS research goals included
validation of satellite-based retrievals of aerosol properties, vertical
profiles of radiative fluxes, temperature and water vapor. Because of
the primary goal of EOS sensor validation, the CV-580 aircraft spent a
considerable amount of time flying low-level transects. During these
transects, AATS-14 measurements frequently revealed the presence of
persistent spatial gradients or general variability in the aerosol
optical depth field \[*Redemann et al*., 2002\]. Figure 2 shows the
spatial variability in AOD as measured during a low level flight leg on
July 17, 2001 in CLAMS. Terra satellite overpass time was at 16:12 UT.

![](media/image3.png){width="6.75in" height="4.631944444444445in"}

**Figure 2.** Spatial variability in AOD at 0.353, 0.525 and 1.558µm
during a low level leg flown on July 17, 2001 in CLAMS (see text).

Figure 3 shows a comparison of the spatial variability in AOD at three
wavelengths (0.353, 0.525 and 1.558µm) as measured during low level
flight legs flown in 11 flights of CLAMS.

![](media/image4.png){width="6.672916666666667in"
height="4.579166666666667in"}

**Figure 3.** Spatial variability in AOD at 0.353, 0.525 and 1.558µm
during low level legs flown in CLAMS (see text).

Figure 3 indicates that, during this time of the year (summer) off the
US East Coast, AOD can change by 40% or more over horizontal distances
less than 50km. Because of the high speed of the aircraft platform
relative to advection wind speed we interpret all of the variability
seen in Figures 2 and 3 to be true instantaneous spatial variability
rather than variability in aerosols due to microphysical evolution
during transport. Figures 2 and 3 further indicate that variability of
10% or more even within a 10km range is not uncommon. This finding is
significant considering that the 10km range is exactly the scale of the
MODIS level 2 data products. The research proposed here is aimed at
determining:

1.  How common is spatial variability of this order of magnitude?

2.  How does this variability compare to other geographic regimes where
    AATS measurements were made?

3.  What are the consequences of such variability for the aerosol
    retrieval algorithms of MODIS and MISR?.

## Measurements of aerosol optical depth in the vicinity of clouds

While the primary objective of the coordinated studies described in
section 3.2 was the validation of satellite sensor data, the data
collected in these studies can be equally useful for investigating
aerosol optical depth variability. In particular, the combination of
aircraft speed and AATS data acquisition rate yields suborbital aerosol
optical depth data at spatial resolution of 100-200 m. As pointed out in
section 2, knowledge of aerosol variability on these spatial scales is
crucial for assessing the performance of cloud masking procedures
currently used in aerosol retrievals of EOS sensors. Therefore, it is
important to assess the spatial variability of AOD in the vicinity of
clouds. Frequently, AATS measurements indicate increased AOD in the
vicinity of clouds on spatial scales of about 1-2 km. Figure 4 (panel 2)
shows an example of such increased AOD in the vicinity of a cloud. The
cloud is identified by a large drop in AATS signal voltages (panel 1)
and a steep drop in the Angstrom exponent (panel 4). Note that the
Angstrom exponent shown in Figure 4 is generally not used for cloud
screening of AATS data. Rather, we use the variability in signal
voltages to separate clouds from aerosols (i.e., blue from green data
points in Figure 4, panel 4) much like the cloud screening procedure
applied in the aerosol retrieval algorithm for MODIS over-ocean
measurements.

![](media/image5.png){width="6.995138888888889in"
height="5.240277777777778in"}

**Figure 4.** Spatial variability in signal strength, AOD and Angstrom
exponent α during a low level leg flown on July, 26, 2001 in CLAMS (see
text).

For orientation, panel 1 of Figure 4 contains boxes of 500 m width - the
same width as the pixels in the MODIS aerosol retrieval algorithms.
Figure 4 indicates increases in AOD at visible wavelengths of 10-25% in
the immediate (500m) vicinity of the cloud field (pixel 4 and 5). It
should be noted that the standard MODIS cloud mask would mask the
increased AOD in pixel 5 simply based on the presence of some cloud
fraction in that pixel. Assuming (for argument's sake) that the surface-
and aerosol-induced radiances at the satellite are comparable within
each pixel in Figure 4, the MODIS over-ocean algorithm would
additionally screen out pixel 4, because the difference of 10% in AOD in
pixel 4 relative to the adjacent pixels would result in standard
deviations of the total .55µm radiances greater than 1% for the set of 9
pixels (the standard deviation threshold for cloud screening being
0.0025 = 0.25%).

One of the goals of the research proposed here is to determine how
common AOD variability of 10% or more in the immediate vicinity of
clouds is in order to determine how frequently such increased AOD is
suppressed when determining average satellite derived radiances for
retrieving aerosol optical depth.

# SUMMARY OF PLANNED ACTIVITIES AS MODIS SCIENCE TEAM MEMBERS

As future MODIS science team members, we propose the combination of
suborbital and satellite (MODIS) measurements to determine the spatial
variability of aerosol optical depth in the vicinity of clouds and
assess how well current EOS satellite sensors capture or suppress such
variability within their processing algorithms. This approach is
directly aimed at answering the ESE questions about Earth's natural
variability (ESE strategic question 1) and how this variability is
captured by EOS sensors. Further, because aerosols are one of the major
climate forcing agents, the aerosol variability work is also aimed at
determining how well EOS sensors measure the primary forcings of the
Earth system (ESE strategic question 2).

In detail, we propose to carry out the following tasks as part of our
project:

1)  Screen the AATS data collected in the 7 field experiments described
    in Table 1 for occurrences of significant spatial variations in
    aerosol optical depth and water vapor in the vicinity of clouds (by
    the time this proposal is being considered for funding, data from
    the ADAM (Asian Dust and Aerosols above Monterey) experiment and the
    Oklahoma SGP ARM IOP may also be available). Select cases when these
    suborbital measurements were coordinated with Terra satellite
    overpasses and analyze the actual cloud masking for the MODIS and/or
    MISR sensors for those incidences. Attempt to determine what
    fraction of the area in the vicinity of clouds was screened out and
    assess what impact such a screening had on the average optical depth
    retrieved by the sensor(s).

2)  Based on the findings in task 1, estimate what fraction of AOD may
    have gone undetected and use correlative measurements of aerosol
    radiative properties in conjunction with a radiative transfer model
    to estimate the fraction of the direct radiative forcing of climate
    that may have gone undetected as a consequence.

3)  Compare the spatial variability in aerosol optical depth and the
    associated performance of the EOS sensors in detecting that
    variability under a variety of regional and climatic conditions.
    Where satellite viewing geometry permits, compare the Terra-MODIS
    and MISR derived aerosol optical depth products and try to assess
    which product captures the variability in suborbital measurements of
    aerosol optical properties more closely.

4)  Make available the validation capabilities of the NASA Ames Airborne
    Sunphotometer group to the MODIS-Atmosphere science team in support
    of future refinements to AOD and water vapor algorithms and future
    developments of over-the-ocean (glint/off-glint) algorithms to
    derive aerosol absorption.

Because our team has been an integral part of aerosol field campaigns,
we expect considerable success in identifying the atmospheric and
surface conditions which are conducive to the accurate inversion of EOS
satellite sensor data. Both the first and the second task will be highly
relevant to the future CALIPSO mission by assessing small-scale aerosol
variability. The findings regarding spatial aerosol variability are
expected to help guide validation efforts for the CALIPSO instrument and
other aerosol sensors envisioned to be flying in the A-Train formation
(POLDER, OMI, MODIS-Aqua).

The cloud-halo work proposed here may lead to refinements of the MODIS
and MISR AOD algorithms. However, such refinements are not considered a
main aspect of this work. The analysis of AATS-derived near-cloud
aerosol optical depth data and its combination with satellite-derived
cloud properties may further lead to insights into aerosol-induced
modifications of cloud properties, hence the aerosol indirect forcing of
climate.

The newly added AATS-14 channel at 2.14µm will be important in
validating future MODIS-Terra and MODIS-Aqua aerosol measurements, in
particular because MODIS-Aqua has had problems with the 1.6µm detectors.
Because the two MODIS near-IR channels (1.6 and 2.1µm) are used
extensively for the determination of cloud and land surface properties
and because the aerosol optical depth data in those channels carries
most of the information on the size of larger particles (thereby
frequently allowing the separation of smaller anthropogenic particles
from larger natural particles), there will be a continued need for
over-the-ocean validation of these data products. Although of lesser
importance to this proposal, we intend to make the resources and
capabilities of the NASA Ames Airborne Sunphotometer team available for
future satellite validation efforts. However, actual costs for deploying
the AATS instruments are not included in this proposal and will have to
be covered by additional funding.

# REFERENCES

Durkee, P. A., K. E. Nielsen, P. J. Smith, P. B. Russell, B. Schmid, J.
M. Livingston, B. N. Holben, D. R. Collins, R. C. Flagan, J. H.
Seinfeld, K. J. Noone, E. Öström, S. Gassó, D. A. Hegg, L. M. Russell,
T. S. Bates, and P. K. Quinn. Regional aerosol properties from satellite
observations: ACE-1, TARFOX and ACE-2 results. *Tellus,* B 52, 484-497,
2000.

Hsu, N. C., Tsay, S, Herman, J Holben, B, Comparisons of satellite
retrieval of aerosol properties from SeaWiFS and TOMS to the AERONET
measurements, *EOS Trans. AGU*, 82 (47), Spring Meet. Suppl., Abstract
A51B-03, 2002.

Husar, R. B., J. M. Prospero and L. L. Stowe, Characterization of
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Kahn, R., P. Banerjee, and D. McDonald, The sensitivity of multiangle
imaging to natural mixtures of aerosols over ocean, *J. Geophys. Res*.,
*106*, 18,219-18,238, 2001.

Kahn R. et al. (with J. Redemann, B. Schmid, P. Russell), Relationships
Among Surface, Airborne, and Satellite Multi-angle Aerosol Observations
During the ACE-Asia Field Campaign, *J. Geophys. Res*., to be submitted,
2003.

Kaufman, Y.J., D. Tanré, L.A. Remer, E. Vermote, A. Chu and B.N. Holben,
Operational remote sensing of tropospheric aerosol over land from EOS
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the climate system, *Nature*, 419, 215-223, 2002.

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J. Redemann, P. Russell, G. L. Schuster, W. J. Rodriquez, K. Rutledge,
R. Kleidman, Y. J. Kaufman, Validation of MODIS Aerosol Retrieval over
the Ocean during CLAMS,  *[EOS Transactions]{.underline}*, Vol. 83, no.
19, pp. S36, 2002.

Levy, R. C., L. A. Remer, D. Tanré, Y. J. Kaufman, C. Ichoku, B. N.
Holben, J. M. Livingston, P. B. Russell, H. Maring, Evaluation of the
MODIS retrievals of dust aerosol over the ocean during PRIDE. *J.
Geophys. Res.*, in press, 2003.

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. Gassó, D. A. 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*, B 52, 594-619, 2000.

Livingston J. M., P. B. Russell, J. S. Reid, J. Redemann, B. Schmid, D.
A. Allen, O. Torres, R. C. Levy, L. A. Remer, B. N. Holben, A. Smirnov,
O. Dubovik, E. J. Welton, J. R. Campbell, J. Wang, S. A. Christopher,
Airborne sunphotometer measurements of aerosol optical depth and
columnar water vapor during the Puerto Rico Dust Experiment, and
comparison with land, aircraft, and satellite measurements, *J. Geophys.
Res.*, in press, 2003.

Martins, J.V., D. Tanré, L.A. Remer, Y.J. Kaufman, S. Mattoo and R.
Levy, 2002: MODIS Cloud screening for remote sensing of aerosol over
oceans using spatial variability. *Geophys. Res. Lett.*, **29**,
10.1029/2001GL013252.

Martonchik, J. V., D. J. Diner, R. Kahn, T. P. Ackerman, M. M.
Verstraete, B. Pinty, and H. R. Gordon, Techniques for the retrieval of
aerosol properties over land and ocean using multiangle imaging. *IEEE
Trans. Geosci. Rem. Sens*., *36*, 1212-1227, 1998.

Prospero, J.M., P. Ginoux, O. Torres, S. Nicholson, and T. Gill.
Environmental characterization of global sources of atmospheric soil
dust identified with the NIMBUS 7 Total Ozone Mapping Spectrometer
(TOMS) absorbing aerosol product. *Reviews of Geophysics*,
10.1029/2000RG000095, 2002.

Ramanathan, V., T. S. Bates, J. E. Hansen, D. J. Jacob, Y. J. Kaufman,
J. E. Penner, M. J. Prather, S. E. Schwartz, and J. H. Seinfeld,
*National Aerosol-Climate Interactions Program (NACIP), A National
Research Imperative*, White Paper, <http://www-NACIP/ucsd.edu>, 2002.

Redemann, J., B. Schmid, J. M. Livingston, P. B. Russell, J. E. Eilers,
P. V. Hobbs, R. Kahn, W. L. Smith Jr., B. Holben , K. Rutledge, Airborne
Sunphotometry in Support of the Chesapeake Lighthouse and Aircraft
Measurements for Satellites (CLAMS) Experiment, 2001, *[EOS
Transactions]{.underline}*, Vol. 82, no. xx, pp. Fxx, 2001.

Redemann, J., B. Schmid, J. M. Livingston, P. B. Russell, et al.,
Airborne Sunphotometer Measurements of Aerosol Optical Depth and Water
Vapor in ACE-Asia and their Comparisons to Correlative Measurements and
Calculations, *Abstracts*, 11^th^ Conference on Atmospheric Radiation,
American Meteorological Society, Ogden, UT, June 3-7, pp. 35, 2002.

Redemann, J., S. Masonis, B. Schmid, T. Anderson, P. Russell, J.
Livingston, O. Dubovik, A. Clarke, Clear-column closure studies of
aerosols and water vapor aboard the NCAR C-130 in ACE-Asia, 2001, *J.
Geophys. Res.* ms# 2002JD00 3442, submitted January 23, 2003.

Remer, L. A., et al., Validation of MODIS aerosol retrieval over ocean,
*Geophys. Res. Lett.,* 29(12), 10.1029/2001GL013204, 2002

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.

Russell, P. B., and J. Heintzenberg, An Overview of the ACE 2 Clear Sky
Column Closure Experiment (CLEARCOLUMN), *Tellus* B 52, 463-483, 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*, B 52, 568-593, 2000.

Schmid B., J.J. Michalsky, D.W. Slater, J.C. Barnard, R.N. Halthore,
J.C. Liljegren, B.N. Holben, T.F. Eck, J.M. Livingston, P.B. Russell, T.
Ingold, and I. Slutsker. Comparison of columnar water-vapor measurements
from solar transmittance methods. *Applied Optics,* Vol. 40, No. 12,
1886-1896, 2001.

Schmid, B., D. A. Hegg, J. Wang, D. Bates, J. Redemann, P. B. Russell,
J. M. Livingston, H. H. Jonsson, E. J. Welton, J. H. Seinfeld, R. C.
Flagan, D. S. Covert, O. Dubovik, A. Jefferson, Column closure studies
of lower tropospheric aerosol and water vapor during ACE-Asia using
airborne sunphotometer, airborne in-situ and ship-based lidar
measurements, *J. Geophys. Res.* ms# 2002JD003361, submitted December
26, 2002.

Schmid B., J. Redemann, P. B. Russell, P. V. Hobbs, D. L. Hlavka, M. J.
McGill, B. N. Holben, E. J. Welton, J. Campbell, O. Torres, R. A. Kahn,
D. J. Diner, M. C. Helmlinger, D. A. Chu, C. Robles Gonzalez, and G. de
Leeuw, Coordinated airborne, spaceborne, and ground-based measurements
of massive, thick aerosol layers during the dry season in Southern
Africa, *J. Geophys. Res*, 108, doi:10.1029/2002JD002297, 2003.

Tanré, D., Y.J. Kaufman, M. Herman and S. Mattoo, 1997: Remote sensing
of aerosol properties over oceans using the MODIS/EOS spectral
radiances. *J. Geophys. Res.*, 102, 16971-16988.

Tanré, D., Remer, L. A., Kaufman, Y. J.; Mattoo, S.; Hobbs, P. V.;
Livingston, J. M.; Russell, P. B.; Smirnov, A. Retrieval of aerosol
optical thickness and size distribution over ocean from the MODIS
airborne simulator during TARFOX. *J. Geophys. Res*. 104 (D2) 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.

Wang J., S. A. Christopher, J. S. Reid, H. Maring, D. Savoie, B. N.
Holben, J. M. Livingston, P. B. Russell, and Shi-Keng Yang. GOES-8
Retrieval of Dust Aerosol Optical Thickness over the Atlantic Ocean
during PRIDE. *J. Geophys. Res.*, in press, 2003a.

Wang J., S. A. Christopher, F. Brechtel, J. Kim, B. Schmid, P. B.
Russell, J. Redemann, B. N. Holben, Geostationary Satellite Retrievals
of Aerosol Optical Thickness during ACE-Asia. *J. Geophys. Res*.,
submitted, 2003b.

# MANAGEMENT PLAN

## Roles of Co-PI's and Co-I

Drs. Beat Schmid and Jens Redemann will be Co-Principal Investigator.
They will be responsible for the overall scientific direction, project
management, administration, and communications with NASA HQ. They will
be responsible for completing the work on time and within budget.

Dr. Philip B. Russell (Co-Investigator) will assist the Co-PI's in the
proposed activities as EOS/MODIS science team members. Dr. Russell will
assist in communications with NASA HQ.

Ms. Stephanie Ramirez will work part-time on this project as a
programmer under the guidance of the PIs'.

BAER Institute and NASA Ames Research Center will furnish additional
personnel necessary to accomplish the research.

# CURRENT SUPPORT OF PI's (B. Schmid/J. Redemann)

+--------------------------+-----------------------+------------------+
| **Short Title**          | **Agency/Task No.**   | **Duration**     |
+--------------------------+-----------------------+------------------+
| Vertically resolved      | DOE ARM Science Team  | 11/2002-10/2005  |
| aerosol optical          |                       |                  |
| properties over the ARM  | DE-AI03-03ER63535     |                  |
| SGP site                 |                       |                  |
+--------------------------+-----------------------+------------------+
| NASA New Investigator    | NASA HQ / NAG5-12573  | 11/2002-10/2005  |
| Program: "Validating EOS |                       |                  |
| Terra sensor retrievals" |                       |                  |
+--------------------------+-----------------------+------------------+
| AATS-14 aboard the       | DOE ARM IOP funds     | 2/2003-12/2003   |
| CIRPAS Twin Otter during |                       |                  |
| the May 2003 Aerosol IOP | ITF 355506-A          |                  |
| over the SGP ARM site    |                       |                  |
+--------------------------+-----------------------+------------------+
| Quantification of        | NOAA, OGP,            | 3/2003-2/2006    |
| aerosol radiative        | Aerosol-Climate       |                  |
| effects by integrated    | Interactions Program. |                  |
| analysis of airborne     |                       |                  |
| measurements, satellite  |                       |                  |
| retrievals, and          |                       |                  |
| radiative transfer       |                       |                  |
| models                   |                       |                  |
+--------------------------+-----------------------+------------------+
| Global Aerosol           | NASA RTOP             | 10/1998-9/2003   |
| Climatology (GACP)       |                       |                  |
|                          | 622-44-75-10          |                  |
+--------------------------+-----------------------+------------------+
| SOLVE-2 Science Team     | NASA                  | 8/2002-6/2003    |
+--------------------------+-----------------------+------------------+

#  BUDGET

## General Budget

## Travel budget

# VITAE

(a) **Beat Schmid**

**Abbreviated Curriculum Vitae**

Education

  -------------------- --------- ------ -------------------------------------------
  M.S.                           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}, Sonoma, CA
(1997-Present)

Senior Research Scientist, Principal Investigator

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

Visiting Scientist

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

Research Assistant (1989-1995)

Postdoctoral Researcher (1995-1997)

Scientific Contributions

-   Conducted 10 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~.

-   Participated 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.

-   Employed NASA Ames Airborne Sun photometers in the US Dept. of
    Energy, Atmospheric Radiation Measurement (ARM) program integrated
    fall 1997 and fall 2000 intensive observation periods in Oklahoma.
    Led sun photometer intercomparison. Extensive comparison of water
    vapor results with radiosondes, microwave radiometers, lidar, and
    Global Positioning System.

-   Operated NASA Ames Airborne Sun photometers in SAFARI 2000 (Southern
    African Regional Science Initiative; August/September 2000).
    Validation of lidar and satellite retrievals.

-   Participated with the NASA Ames Airborne Sun photometers in ACE-Asia
    (Asian Pacific Regional Aerosol Characterization Experiment; April
    2001). Closure studies, satellite and lidar validation.

-   Operated the NASA Ames Cavity Ringdown instrument in Reno Aerosol
    Optics Study (June, 2002). Comparison of aerosol extinction,
    scattering and absorption from various methods (cavitiy ring down,
    photo-acoustic, nephelometer, filter based)

-   Led planning of DOE ARM May 03 Aerosol Intensive Observation Period.
    Responsible for defining airborne payload on the CIRPAS Twin Otter
    aircraft.

-   Evaluated candidate methods for SAGE III satellite ozone/aerosol
    separation using airborne sunphotometer data.

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

Scientific Societies/Editorships

-   Associate Editor, *Journal Geophysical Research* (2002- )

-   Member, American Geophysical Union and American Meteorological
    Society

Grants

-   Principal Investigator, DOE ARM Science Team.

-   Principal Investigator on two Cooperative Agreements between Bay
    Area Environmental Research Institute and NASA Ames Research Center
    since 2000. Responsible for research and financial administration of
    3.5 fulltime scientists.

-   Co-PI and Co-I on numerous research grants funded by NASA, NOAA,
    Office of Naval Research (ONR) and National Science Foundation
    (NSF).

Bibliography

-   28 peer-reviewed journal articles (8 first-authored)

-   5 peer-reviewed journal articles (1 first-authored) submitted
    recently

-   97 conference publications (23 first-authored)

-   13 invited talks at conferences, workshops and seminars

Publications relevant to this NRA are listed in section 5 of this
proposal

**(b) Jens Redemann**

> **Abbreviated Curriculum Vitae**

PROFESSIONAL EXPERIENCE

  --------------------- ----------------- --------------------------------
  Senior Research       BAERI, Sonoma, CA **April 1999 to present**
  Scientist                               

  Research Assistant    UCLA, CA          **May 1995 to March 1999**

  Lecturer              UCLA, CA          **Jan. 1999 to present**

  Research Assistant    FU Berlin,        **June 1994 to April 1995**
                        Germany           
  --------------------- ----------------- --------------------------------

EDUCATION

+----------------------------------+-----------------------------------+
| Ph.D. in Atmospheric Sciences,   | > **1999**                        |
| UCLA.                            |                                   |
+----------------------------------+-----------------------------------+
| M.S. in Atmospheric Sciences,    | > **1997**                        |
| UCLA.                            |                                   |
+----------------------------------+-----------------------------------+
| M.S. in Physics, FU Berlin,      | > **1995**                        |
| Germany.                         |                                   |
+----------------------------------+-----------------------------------+

RELEVANT RESEARCH EXPERIENCE

-   Principal Investigator, NASA New Investigator Program, 2002-2005.

-   Principal Investigator for the participation of AATS-14 (a
    narrow-band tracking sunphotometer) in the CLAMS satellite
    validation study (July 2001). Responsible for proposal writing and
    experiment design, instrument integration, as well as scheduling and
    supervision of three group members.

-   Developed a coupled aerosol microphysics and chemistry model to
    study the dependence of the aerosol single scattering albedo on
    ambient relative humidity.

-   Related airborne measurements using a sunphotometer, a lidar (light
    detection and ranging) system and a spectral solar flux radiometer
    to in situ measurements of atmospheric (mineral dust) aerosols and
    gases and modeled the local radiative transfer in Earth's
    atmosphere.

-   Participated in the SAFARI-2000, ACE-Asia, PRIDE and CLAMS field
    experiments aimed at investigating atmospheric aerosols. Member of
    CLAMS (Chesapeake Lighthouse Aerosol Measurements for Satellites)
    science team.

-   Utilized satellite derived aerosol optical depth fields and aerosol
    properties from the ACE-Asia campaign to determine the aerosol
    radiative forcing of climate in the Pacific Basin troposphere.

HONORS / ORGANIZATIONS

+----------------------------------------------------------+-----------+
| Invited Presentation at the 5^th^ International APEX     | #### **   |
| workshop, Miyazaki, Japan.                               | July 2002 |
|                                                          | ** {#july |
|                                                          | -2002 .un |
|                                                          | numbered} |
+----------------------------------------------------------+-----------+
| Invited Presentation at the Atmospheric Chemistry        | ##        |
| Colloquium for Emerging Senior Scientists (ACCESS V).    | ## **1999 |
|                                                          | ** {#sect |
|                                                          | ion-1 .un |
|                                                          | numbered} |
+----------------------------------------------------------+-----------+
| Outstanding Student Paper Award, AGU Fall meeting.       | **1998**  |
+----------------------------------------------------------+-----------+
| NASA Global Change Research Fellowship Awards.           | **19      |
|                                                          | 95-1998** |
+----------------------------------------------------------+-----------+
| UCLA Neiburger Award for excellence in teaching of the   | **1997**  |
| atmospheric sciences.                                    |           |
+----------------------------------------------------------+-----------+

SUMMARY OF BIBLIOGRAPHY

12 peer-reviewed journal articles (6 first-authored).

34 conference presentations (23 first-authored).

Publications relevant to this NRA are listed in section 5 of this
proposal.

**(c)** **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, Earth
System Science Division (1988-89), Chief, Atmospheric Chemistry and
Dynamics Branch (1989-95), Research Scientist (1995-present), NASA Ames
Research Center.

NASA Ames Honor Award (2002, for excellence in scientific research).
NASA Ames Associate Fellow (1995, for excellence in atmospheric
science). NASA Space Act Award (1989, for invention of Airborne
Autotracking Sunphotometer). NASA Exceptional Service Medal (1988, for
managing Stratosphere-Troposphere Exchange Project). Member, Phi Beta
Kappa and Sigma Xi.

Currently, Member, Science Teams for NASA's Earth Observing System
Inter-Disciplinary Science (EOS-IDS) and the Asian Pacific Regional
Aerosol Characterization Experiment (ACE-Asia) of the International
Global Atmospheric Chemistry (IGAC) Project.

Previously, Mission Scientist for ACE-Asia C-130 flights addressing
aerosol-radiation interactions. Co-coordinator for the CLEARCOLUMN
component of IGAC's Second Aerosol Characterization Experiment (ACE-2).
Coordinator for IGAC's Tropospheric Aerosol Radiative Forcing
Observational Experiment (TARFOX). Member, Science Teams for SAGE II and
SAGE III (satellite sensors of stratospheric aerosols, ozone, nitrogen
dioxide, and water vapor). Member, Science Team for Global Aerosol
Climatology Project (GACP).

Previously, Editor-in-Chief (1994-95) and Editor (1993, 1996),
*Geophysical Research Letters*. Chair, American Meteorological Society
Committee on Laser Atmospheric Studies (1979-82). Member, AMS Committee
on Radiation Energy (1979-81). Member, National Research Council
Committee on Army Basic Research (1979-81).

Previously, Project Scientist, Small High-Altitude Science Aircraft
(SHASA) Project to develop the Perseus A Remotely Piloted Aircraft (RPA,
1992-94). 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).

Over 100 peer-reviewed publications. Selected publications relevant to
this NRA are included in section 5 of this proposal.