+---------+---+---+---+------------+------+----------+---+---------------+
| ![]     |   |   | # |            |      |          |   | NRA-02-OES-06 |
| (media/ |   |   | # |            |      |          |   |               |
| image1. |   |   | # |            |      |          |   | Proposal      |
| jpeg){w |   |   | # |            |      |          |   | Number:       |
| idth="0 |   |   |   |            |      |          |   |               |
| .675in" |   |   | P |            |      |          |   | (Leave blank  |
| he      |   |   | r |            |      |          |   | for NASA use) |
| ight="0 |   |   | o |            |      |          |   |               |
| .582638 |   |   | p |            |      |          |   |               |
| 8888888 |   |   | o |            |      |          |   |               |
| 889in"} |   |   | s |            |      |          |   |               |
|         |   |   | a |            |      |          |   |               |
|         |   |   | l |            |      |          |   |               |
|         |   |   |   |            |      |          |   |               |
|         |   |   | C |            |      |          |   |               |
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|         |   |   | { |            |      |          |   |               |
|         |   |   | . |            |      |          |   |               |
|         |   |   | u |            |      |          |   |               |
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|         |   |   | d |            |      |          |   |               |
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|         |   |   | } |            |      |          |   |               |
+---------+---+---+---+------------+------+----------+---+---------------+
| ### Nam |   |   |   | NASA Ames  |      | **Congr  |   | California    |
| e of Su |   |   |   | Research   |      | essional |   | #14           |
| bmittin |   |   |   | Center     |      | Dis      |   |               |
| g Insti |   |   |   |            |      | trict:** |   |               |
| tution: |   |   |   |            |      |          |   |               |
+---------+---+---+---+------------+------+----------+---+---------------+
| **P     | S |   |   |            |      |          |   |               |
| roposal | a |   |   |            |      |          |   |               |
| T       | t |   |   |            |      |          |   |               |
| itle:** | e |   |   |            |      |          |   |               |
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|         | i |   |   |            |      |          |   |               |
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|         | u |   |   |            |      |          |   |               |
|         | n |   |   |            |      |          |   |               |
|         | p |   |   |            |      |          |   |               |
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|         | m |   |   |            |      |          |   |               |
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|         |   |   |   |            |      |          |   |               |
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|         | ) |   |   |            |      |          |   |               |
|         | a |   |   |            |      |          |   |               |
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|         | d |   |   |            |      |          |   |               |
|         | R |   |   |            |      |          |   |               |
|         | a |   |   |            |      |          |   |               |
|         | d |   |   |            |      |          |   |               |
|         | i |   |   |            |      |          |   |               |
|         | a |   |   |            |      |          |   |               |
|         | t |   |   |            |      |          |   |               |
|         | i |   |   |            |      |          |   |               |
|         | o |   |   |            |      |          |   |               |
|         | n |   |   |            |      |          |   |               |
|         | S |   |   |            |      |          |   |               |
|         | c |   |   |            |      |          |   |               |
|         | i |   |   |            |      |          |   |               |
|         | e |   |   |            |      |          |   |               |
|         | n |   |   |            |      |          |   |               |
|         | c |   |   |            |      |          |   |               |
|         | e |   |   |            |      |          |   |               |
|         | P |   |   |            |      |          |   |               |
|         | r |   |   |            |      |          |   |               |
|         | o |   |   |            |      |          |   |               |
|         | g |   |   |            |      |          |   |               |
|         | r |   |   |            |      |          |   |               |
|         | a |   |   |            |      |          |   |               |
|         | m |   |   |            |      |          |   |               |
|         | s |   |   |            |      |          |   |               |
|         | ) |   |   |            |      |          |   |               |
+---------+---+---+---+------------+------+----------+---+---------------+
| # Ce    |   |   |   |            |      |          |   |               |
| rtifica |   |   |   |            |      |          |   |               |
| tion of |   |   |   |            |      |          |   |               |
|  Compli |   |   |   |            |      |          |   |               |
| ance wi |   |   |   |            |      |          |   |               |
| th Appl |   |   |   |            |      |          |   |               |
| icable  |   |   |   |            |      |          |   |               |
| Executi |   |   |   |            |      |          |   |               |
| ve Orde |   |   |   |            |      |          |   |               |
| rs and  |   |   |   |            |      |          |   |               |
| US Code |   |   |   |            |      |          |   |               |
|         |   |   |   |            |      |          |   |               |
| By      |   |   |   |            |      |          |   |               |
| sub     |   |   |   |            |      |          |   |               |
| mitting |   |   |   |            |      |          |   |               |
| the     |   |   |   |            |      |          |   |               |
| p       |   |   |   |            |      |          |   |               |
| roposal |   |   |   |            |      |          |   |               |
| ide     |   |   |   |            |      |          |   |               |
| ntified |   |   |   |            |      |          |   |               |
| in this |   |   |   |            |      |          |   |               |
| *Cover  |   |   |   |            |      |          |   |               |
| Sheet/P |   |   |   |            |      |          |   |               |
| roposal |   |   |   |            |      |          |   |               |
| S       |   |   |   |            |      |          |   |               |
| ummary* |   |   |   |            |      |          |   |               |
| in      |   |   |   |            |      |          |   |               |
| r       |   |   |   |            |      |          |   |               |
| esponse |   |   |   |            |      |          |   |               |
| to this |   |   |   |            |      |          |   |               |
| R       |   |   |   |            |      |          |   |               |
| esearch |   |   |   |            |      |          |   |               |
| Announ  |   |   |   |            |      |          |   |               |
| cement, |   |   |   |            |      |          |   |               |
| the     |   |   |   |            |      |          |   |               |
| Auth    |   |   |   |            |      |          |   |               |
| orizing |   |   |   |            |      |          |   |               |
| O       |   |   |   |            |      |          |   |               |
| fficial |   |   |   |            |      |          |   |               |
| of the  |   |   |   |            |      |          |   |               |
| pr      |   |   |   |            |      |          |   |               |
| oposing |   |   |   |            |      |          |   |               |
| inst    |   |   |   |            |      |          |   |               |
| itution |   |   |   |            |      |          |   |               |
| (or the |   |   |   |            |      |          |   |               |
| ind     |   |   |   |            |      |          |   |               |
| ividual |   |   |   |            |      |          |   |               |
| p       |   |   |   |            |      |          |   |               |
| roposer |   |   |   |            |      |          |   |               |
| if      |   |   |   |            |      |          |   |               |
| there   |   |   |   |            |      |          |   |               |
| is no   |   |   |   |            |      |          |   |               |
| pr      |   |   |   |            |      |          |   |               |
| oposing |   |   |   |            |      |          |   |               |
| insti   |   |   |   |            |      |          |   |               |
| tution) |   |   |   |            |      |          |   |               |
| as      |   |   |   |            |      |          |   |               |
| ide     |   |   |   |            |      |          |   |               |
| ntified |   |   |   |            |      |          |   |               |
| below:  |   |   |   |            |      |          |   |               |
|         |   |   |   |            |      |          |   |               |
| -   ce  |   |   |   |            |      |          |   |               |
| rtifies |   |   |   |            |      |          |   |               |
|         |   |   |   |            |      |          |   |               |
|    that |   |   |   |            |      |          |   |               |
|     the |   |   |   |            |      |          |   |               |
|     sta |   |   |   |            |      |          |   |               |
| tements |   |   |   |            |      |          |   |               |
|         |   |   |   |            |      |          |   |               |
|    made |   |   |   |            |      |          |   |               |
|     in  |   |   |   |            |      |          |   |               |
|         |   |   |   |            |      |          |   |               |
|    this |   |   |   |            |      |          |   |               |
|     p   |   |   |   |            |      |          |   |               |
| roposal |   |   |   |            |      |          |   |               |
|     are |   |   |   |            |      |          |   |               |
|         |   |   |   |            |      |          |   |               |
|    true |   |   |   |            |      |          |   |               |
|     and |   |   |   |            |      |          |   |               |
|     c   |   |   |   |            |      |          |   |               |
| omplete |   |   |   |            |      |          |   |               |
|     to  |   |   |   |            |      |          |   |               |
|     the |   |   |   |            |      |          |   |               |
|         |   |   |   |            |      |          |   |               |
|    best |   |   |   |            |      |          |   |               |
|     of  |   |   |   |            |      |          |   |               |
|         |   |   |   |            |      |          |   |               |
| his/her |   |   |   |            |      |          |   |               |
|     kno |   |   |   |            |      |          |   |               |
| wledge; |   |   |   |            |      |          |   |               |
|         |   |   |   |            |      |          |   |               |
| -       |   |   |   |            |      |          |   |               |
|  agrees |   |   |   |            |      |          |   |               |
|     to  |   |   |   |            |      |          |   |               |
|         |   |   |   |            |      |          |   |               |
|  accept |   |   |   |            |      |          |   |               |
|     the |   |   |   |            |      |          |   |               |
|         |   |   |   |            |      |          |   |               |
|    obli |   |   |   |            |      |          |   |               |
| gations |   |   |   |            |      |          |   |               |
|     to  |   |   |   |            |      |          |   |               |
|         |   |   |   |            |      |          |   |               |
|  comply |   |   |   |            |      |          |   |               |
|         |   |   |   |            |      |          |   |               |
|    with |   |   |   |            |      |          |   |               |
|         |   |   |   |            |      |          |   |               |
|    NASA |   |   |   |            |      |          |   |               |
|         |   |   |   |            |      |          |   |               |
|   award |   |   |   |            |      |          |   |               |
|         |   |   |   |            |      |          |   |               |
|   terms |   |   |   |            |      |          |   |               |
|     and |   |   |   |            |      |          |   |               |
|     con |   |   |   |            |      |          |   |               |
| ditions |   |   |   |            |      |          |   |               |
|     if  |   |   |   |            |      |          |   |               |
|     an  |   |   |   |            |      |          |   |               |
|         |   |   |   |            |      |          |   |               |
|   award |   |   |   |            |      |          |   |               |
|     is  |   |   |   |            |      |          |   |               |
|         |   |   |   |            |      |          |   |               |
|    made |   |   |   |            |      |          |   |               |
|     as  |   |   |   |            |      |          |   |               |
|     a   |   |   |   |            |      |          |   |               |
|         |   |   |   |            |      |          |   |               |
|  result |   |   |   |            |      |          |   |               |
|     of  |   |   |   |            |      |          |   |               |
|         |   |   |   |            |      |          |   |               |
|    this |   |   |   |            |      |          |   |               |
|     pr  |   |   |   |            |      |          |   |               |
| oposal; |   |   |   |            |      |          |   |               |
|     and |   |   |   |            |      |          |   |               |
|         |   |   |   |            |      |          |   |               |
| -   c   |   |   |   |            |      |          |   |               |
| onfirms |   |   |   |            |      |          |   |               |
|     com |   |   |   |            |      |          |   |               |
| pliance |   |   |   |            |      |          |   |               |
|         |   |   |   |            |      |          |   |               |
|    with |   |   |   |            |      |          |   |               |
|     all |   |   |   |            |      |          |   |               |
|         |   |   |   |            |      |          |   |               |
|    prov |   |   |   |            |      |          |   |               |
| isions, |   |   |   |            |      |          |   |               |
|         |   |   |   |            |      |          |   |               |
|  rules, |   |   |   |            |      |          |   |               |
|     and |   |   |   |            |      |          |   |               |
|         |   |   |   |            |      |          |   |               |
|   stipu |   |   |   |            |      |          |   |               |
| lations |   |   |   |            |      |          |   |               |
|     set |   |   |   |            |      |          |   |               |
|         |   |   |   |            |      |          |   |               |
|   forth |   |   |   |            |      |          |   |               |
|     in  |   |   |   |            |      |          |   |               |
|     the |   |   |   |            |      |          |   |               |
|     two |   |   |   |            |      |          |   |               |
|         |   |   |   |            |      |          |   |               |
| Certifi |   |   |   |            |      |          |   |               |
| cations |   |   |   |            |      |          |   |               |
|     co  |   |   |   |            |      |          |   |               |
| ntained |   |   |   |            |      |          |   |               |
|     in  |   |   |   |            |      |          |   |               |
|         |   |   |   |            |      |          |   |               |
|    this |   |   |   |            |      |          |   |               |
|     NRA |   |   |   |            |      |          |   |               |
|     \[  |   |   |   |            |      |          |   |               |
| namely, |   |   |   |            |      |          |   |               |
|         |   |   |   |            |      |          |   |               |
|    (i*) |   |   |   |            |      |          |   |               |
|     As  |   |   |   |            |      |          |   |               |
| surance |   |   |   |            |      |          |   |               |
|     of  |   |   |   |            |      |          |   |               |
|     Com |   |   |   |            |      |          |   |               |
| pliance |   |   |   |            |      |          |   |               |
|         |   |   |   |            |      |          |   |               |
|    with |   |   |   |            |      |          |   |               |
|     the |   |   |   |            |      |          |   |               |
|         |   |   |   |            |      |          |   |               |
|    NASA |   |   |   |            |      |          |   |               |
|         |   |   |   |            |      |          |   |               |
|    Regu |   |   |   |            |      |          |   |               |
| lations |   |   |   |            |      |          |   |               |
|     P   |   |   |   |            |      |          |   |               |
| ursuant |   |   |   |            |      |          |   |               |
|     to  |   |   |   |            |      |          |   |               |
|     Non |   |   |   |            |      |          |   |               |
| discrim |   |   |   |            |      |          |   |               |
| ination |   |   |   |            |      |          |   |               |
|     in  |   |   |   |            |      |          |   |               |
|     Fe  |   |   |   |            |      |          |   |               |
| derally |   |   |   |            |      |          |   |               |
|     A   |   |   |   |            |      |          |   |               |
| ssisted |   |   |   |            |      |          |   |               |
|     Pro |   |   |   |            |      |          |   |               |
| grams*, |   |   |   |            |      |          |   |               |
|     *a  |   |   |   |            |      |          |   |               |
| nd (ii) |   |   |   |            |      |          |   |               |
|     C   |   |   |   |            |      |          |   |               |
| ertific |   |   |   |            |      |          |   |               |
| ations, |   |   |   |            |      |          |   |               |
|         |   |   |   |            |      |          |   |               |
|   Discl |   |   |   |            |      |          |   |               |
| osures, |   |   |   |            |      |          |   |               |
|     And |   |   |   |            |      |          |   |               |
|     Ass |   |   |   |            |      |          |   |               |
| urances |   |   |   |            |      |          |   |               |
|     Re  |   |   |   |            |      |          |   |               |
| garding |   |   |   |            |      |          |   |               |
|     L   |   |   |   |            |      |          |   |               |
| obbying |   |   |   |            |      |          |   |               |
|     and |   |   |   |            |      |          |   |               |
|     De  |   |   |   |            |      |          |   |               |
| barment |   |   |   |            |      |          |   |               |
|     &   |   |   |   |            |      |          |   |               |
|     Su  |   |   |   |            |      |          |   |               |
| spensio |   |   |   |            |      |          |   |               |
| n*\]*.* |   |   |   |            |      |          |   |               |
|         |   |   |   |            |      |          |   |               |
| Willful |   |   |   |            |      |          |   |               |
| pr      |   |   |   |            |      |          |   |               |
| ovision |   |   |   |            |      |          |   |               |
| of      |   |   |   |            |      |          |   |               |
| false   |   |   |   |            |      |          |   |               |
| info    |   |   |   |            |      |          |   |               |
| rmation |   |   |   |            |      |          |   |               |
| in this |   |   |   |            |      |          |   |               |
| p       |   |   |   |            |      |          |   |               |
| roposal |   |   |   |            |      |          |   |               |
| and/or  |   |   |   |            |      |          |   |               |
| its     |   |   |   |            |      |          |   |               |
| sup     |   |   |   |            |      |          |   |               |
| porting |   |   |   |            |      |          |   |               |
| doc     |   |   |   |            |      |          |   |               |
| uments, |   |   |   |            |      |          |   |               |
| or in   |   |   |   |            |      |          |   |               |
| reports |   |   |   |            |      |          |   |               |
| r       |   |   |   |            |      |          |   |               |
| equired |   |   |   |            |      |          |   |               |
| under   |   |   |   |            |      |          |   |               |
| an      |   |   |   |            |      |          |   |               |
| ensuing |   |   |   |            |      |          |   |               |
| award,  |   |   |   |            |      |          |   |               |
| is a    |   |   |   |            |      |          |   |               |
| c       |   |   |   |            |      |          |   |               |
| riminal |   |   |   |            |      |          |   |               |
| offense |   |   |   |            |      |          |   |               |
| (U.S.   |   |   |   |            |      |          |   |               |
| Code,   |   |   |   |            |      |          |   |               |
| Title   |   |   |   |            |      |          |   |               |
| 18,     |   |   |   |            |      |          |   |               |
| Section |   |   |   |            |      |          |   |               |
| 1001).  |   |   |   |            |      |          |   |               |
|         |   |   |   |            |      |          |   |               |
| **[NASA |   |   |   |            |      |          |   |               |
| PR      |   |   |   |            |      |          |   |               |
| OCEDURE |   |   |   |            |      |          |   |               |
| FOR     |   |   |   |            |      |          |   |               |
| H       |   |   |   |            |      |          |   |               |
| ANDLING |   |   |   |            |      |          |   |               |
| PRO     |   |   |   |            |      |          |   |               |
| POSALS] |   |   |   |            |      |          |   |               |
| {.under |   |   |   |            |      |          |   |               |
| line}** |   |   |   |            |      |          |   |               |
|         |   |   |   |            |      |          |   |               |
| This    |   |   |   |            |      |          |   |               |
| p       |   |   |   |            |      |          |   |               |
| roposal |   |   |   |            |      |          |   |               |
| shall   |   |   |   |            |      |          |   |               |
| be used |   |   |   |            |      |          |   |               |
| and     |   |   |   |            |      |          |   |               |
| di      |   |   |   |            |      |          |   |               |
| sclosed |   |   |   |            |      |          |   |               |
| for     |   |   |   |            |      |          |   |               |
| eva     |   |   |   |            |      |          |   |               |
| luation |   |   |   |            |      |          |   |               |
| p       |   |   |   |            |      |          |   |               |
| urposes |   |   |   |            |      |          |   |               |
| only,   |   |   |   |            |      |          |   |               |
| and a   |   |   |   |            |      |          |   |               |
| copy of |   |   |   |            |      |          |   |               |
| this    |   |   |   |            |      |          |   |               |
| Gov     |   |   |   |            |      |          |   |               |
| ernment |   |   |   |            |      |          |   |               |
| notice  |   |   |   |            |      |          |   |               |
| shall   |   |   |   |            |      |          |   |               |
| be      |   |   |   |            |      |          |   |               |
| applied |   |   |   |            |      |          |   |               |
| to any  |   |   |   |            |      |          |   |               |
| repro   |   |   |   |            |      |          |   |               |
| duction |   |   |   |            |      |          |   |               |
| or      |   |   |   |            |      |          |   |               |
| a       |   |   |   |            |      |          |   |               |
| bstract |   |   |   |            |      |          |   |               |
| t       |   |   |   |            |      |          |   |               |
| hereof. |   |   |   |            |      |          |   |               |
| Any     |   |   |   |            |      |          |   |               |
| aut     |   |   |   |            |      |          |   |               |
| horized |   |   |   |            |      |          |   |               |
| rest    |   |   |   |            |      |          |   |               |
| rictive |   |   |   |            |      |          |   |               |
| notices |   |   |   |            |      |          |   |               |
| that    |   |   |   |            |      |          |   |               |
| the     |   |   |   |            |      |          |   |               |
| su      |   |   |   |            |      |          |   |               |
| bmitter |   |   |   |            |      |          |   |               |
| places  |   |   |   |            |      |          |   |               |
| on this |   |   |   |            |      |          |   |               |
| p       |   |   |   |            |      |          |   |               |
| roposal |   |   |   |            |      |          |   |               |
| shall   |   |   |   |            |      |          |   |               |
| also be |   |   |   |            |      |          |   |               |
| s       |   |   |   |            |      |          |   |               |
| trictly |   |   |   |            |      |          |   |               |
| c       |   |   |   |            |      |          |   |               |
| omplied |   |   |   |            |      |          |   |               |
| with.   |   |   |   |            |      |          |   |               |
| Dis     |   |   |   |            |      |          |   |               |
| closure |   |   |   |            |      |          |   |               |
| of this |   |   |   |            |      |          |   |               |
| p       |   |   |   |            |      |          |   |               |
| roposal |   |   |   |            |      |          |   |               |
| for any |   |   |   |            |      |          |   |               |
| reason  |   |   |   |            |      |          |   |               |
| outside |   |   |   |            |      |          |   |               |
| the     |   |   |   |            |      |          |   |               |
| Gov     |   |   |   |            |      |          |   |               |
| ernment |   |   |   |            |      |          |   |               |
| eva     |   |   |   |            |      |          |   |               |
| luation |   |   |   |            |      |          |   |               |
| p       |   |   |   |            |      |          |   |               |
| urposes |   |   |   |            |      |          |   |               |
| shall   |   |   |   |            |      |          |   |               |
| be made |   |   |   |            |      |          |   |               |
| only to |   |   |   |            |      |          |   |               |
| the     |   |   |   |            |      |          |   |               |
| extent  |   |   |   |            |      |          |   |               |
| aut     |   |   |   |            |      |          |   |               |
| horized |   |   |   |            |      |          |   |               |
| by the  |   |   |   |            |      |          |   |               |
+---------+---+---+---+------------+------+----------+---+---------------+
| ##      |   | P |   |            | **Au |          | D |               |
| ### Pri |   | h |   |            | thor |          | a |               |
| ncipal  |   | i |   |            | ized |          | v |               |
|         |   | l |   |            | I    |          | i |               |
| **Inves |   | i |   |            | nsti |          | d |               |
| tigator |   | p |   |            | tuti |          | L |               |
| Name:** |   | B |   |            | onal |          | . |               |
|         |   | . |   |            | Offi |          | P |               |
|         |   | R |   |            | cial |          | e |               |
|         |   | u |   |            | Nam  |          | t |               |
|         |   | s |   |            | e:** |          | e |               |
|         |   | s |   |            |      |          | r |               |
|         |   | e |   |            |      |          | s |               |
|         |   | l |   |            |      |          | o |               |
|         |   | l |   |            |      |          | n |               |
+---------+---+---+---+------------+------+----------+---+---------------+
| **O     |   | N |   |            | *    |          | N |               |
| rganiza |   | A |   |            | *Org |          | A |               |
| tion:** |   | S |   |            | aniz |          | S |               |
|         |   | A |   |            | atio |          | A |               |
|         |   | A |   |            | n:** |          | A |               |
|         |   | m |   |            |      |          | m |               |
|         |   | e |   |            |      |          | e |               |
|         |   | s |   |            |      |          | s |               |
|         |   | R |   |            |      |          | R |               |
|         |   | e |   |            |      |          | e |               |
|         |   | s |   |            |      |          | s |               |
|         |   | e |   |            |      |          | e |               |
|         |   | a |   |            |      |          | a |               |
|         |   | r |   |            |      |          | r |               |
|         |   | c |   |            |      |          | c |               |
|         |   | h |   |            |      |          | h |               |
|         |   | C |   |            |      |          | C |               |
|         |   | e |   |            |      |          | e |               |
|         |   | n |   |            |      |          | n |               |
|         |   | t |   |            |      |          | t |               |
|         |   | e |   |            |      |          | e |               |
|         |   | r |   |            |      |          | r |               |
+---------+---+---+---+------------+------+----------+---+---------------+
| *       |   | A |   |            | **   |          | E |               |
| *Depart |   | t |   |            | Depa |          | a |               |
| ment:** |   | m |   |            | rtme |          | r |               |
|         |   | o |   |            | nt** |          | t |               |
|         |   | s |   |            |      |          | h |               |
|         |   | p |   |            |      |          | S |               |
|         |   | h |   |            |      |          | c |               |
|         |   | e |   |            |      |          | i |               |
|         |   | r |   |            |      |          | e |               |
|         |   | i |   |            |      |          | n |               |
|         |   | c |   |            |      |          | c |               |
|         |   | C |   |            |      |          | e |               |
|         |   | h |   |            |      |          | D |               |
|         |   | e |   |            |      |          | i |               |
|         |   | m |   |            |      |          | v |               |
|         |   | i |   |            |      |          | i |               |
|         |   | s |   |            |      |          | s |               |
|         |   | t |   |            |      |          | i |               |
|         |   | r |   |            |      |          | o |               |
|         |   | y |   |            |      |          | n |               |
|         |   | a |   |            |      |          |   |               |
|         |   | n |   |            |      |          |   |               |
|         |   | d |   |            |      |          |   |               |
|         |   | D |   |            |      |          |   |               |
|         |   | y |   |            |      |          |   |               |
|         |   | n |   |            |      |          |   |               |
|         |   | a |   |            |      |          |   |               |
|         |   | m |   |            |      |          |   |               |
|         |   | i |   |            |      |          |   |               |
|         |   | c |   |            |      |          |   |               |
|         |   | s |   |            |      |          |   |               |
|         |   | B |   |            |      |          |   |               |
|         |   | r |   |            |      |          |   |               |
|         |   | a |   |            |      |          |   |               |
|         |   | n |   |            |      |          |   |               |
|         |   | c |   |            |      |          |   |               |
|         |   | h |   |            |      |          |   |               |
+---------+---+---+---+------------+------+----------+---+---------------+
| **      |   | M |   |            | *    |          | M |               |
| Mailing |   | S |   |            | *Mai |          | S |               |
| Add     |   | 2 |   |            | ling |          | 2 |               |
| ress:** |   | 4 |   |            | Ad   |          | 4 |               |
|         |   | 5 |   |            | dres |          | 5 |               |
|         |   | - |   |            | s:** |          | - |               |
|         |   | 5 |   |            |      |          | 4 |               |
+---------+---+---+---+------------+------+----------+---+---------------+
| **City, |   | M |   |            | **C  |          | M |               |
| State   |   | o |   |            | ity, |          | o |               |
| Zip:**  |   | f |   |            | S    |          | f |               |
|         |   | f |   |            | tate |          | f |               |
|         |   | e |   |            | Zi   |          | e |               |
|         |   | t |   |            | p:** |          | t |               |
|         |   | t |   |            |      |          | t |               |
|         |   | F |   |            |      |          | F |               |
|         |   | i |   |            |      |          | i |               |
|         |   | e |   |            |      |          | e |               |
|         |   | l |   |            |      |          | l |               |
|         |   | d |   |            |      |          | d |               |
|         |   | , |   |            |      |          | , |               |
|         |   | C |   |            |      |          | C |               |
|         |   | A |   |            |      |          | A |               |
|         |   | 9 |   |            |      |          | 9 |               |
|         |   | 4 |   |            |      |          | 4 |               |
|         |   | 0 |   |            |      |          | 0 |               |
|         |   | 3 |   |            |      |          | 3 |               |
|         |   | 5 |   |            |      |          | 5 |               |
|         |   | - |   |            |      |          | - |               |
|         |   | 1 |   |            |      |          | 1 |               |
|         |   | 0 |   |            |      |          | 0 |               |
|         |   | 0 |   |            |      |          | 0 |               |
|         |   | 0 |   |            |      |          | 0 |               |
+---------+---+---+---+------------+------+----------+---+---------------+
| **Te    |   | 6 |   |            | **T  |          | 6 |               |
| lephone |   | 5 |   |            | elep |          | 5 |               |
| Nu      |   | 0 |   |            | hone |          | 0 |               |
| mber:** |   | - |   |            | N    |          | - |               |
|         |   | 6 |   |            | umbe |          | 6 |               |
|         |   | 0 |   |            | r:** |          | 0 |               |
|         |   | 4 |   |            |      |          | 4 |               |
|         |   | - |   |            |      |          | - |               |
|         |   | 5 |   |            |      |          | 5 |               |
|         |   | 4 |   |            |      |          | 8 |               |
|         |   | 0 |   |            |      |          | 9 |               |
|         |   | 4 |   |            |      |          | 9 |               |
+---------+---+---+---+------------+------+----------+---+---------------+
| **Fax   |   | 6 |   |            | *    |          | 6 |               |
| Nu      |   | 5 |   |            | *Fax |          | 5 |               |
| mber:** |   | 0 |   |            | N    |          | 0 |               |
|         |   | - |   |            | umbe |          | - |               |
|         |   | 6 |   |            | r:** |          | 6 |               |
|         |   | 0 |   |            |      |          | 0 |               |
|         |   | 4 |   |            |      |          | 4 |               |
|         |   | - |   |            |      |          | - |               |
|         |   | 6 |   |            |      |          | 3 |               |
|         |   | 7 |   |            |      |          | 6 |               |
|         |   | 7 |   |            |      |          | 2 |               |
|         |   | 9 |   |            |      |          | 5 |               |
+---------+---+---+---+------------+------+----------+---+---------------+
| **Email |   | [ |   |            | **E  |          | [ |               |
| Add     |   | p |   |            | mail |          | d |               |
| ress:** |   | r |   |            | Ad   |          | p |               |
|         |   | u |   |            | dres |          | e |               |
|         |   | s |   |            | s:** |          | t |               |
|         |   | s |   |            |      |          | e |               |
|         |   | e |   |            |      |          | r |               |
|         |   | l |   |            |      |          | s |               |
|         |   | l |   |            |      |          | o |               |
|         |   | @ |   |            |      |          | n |               |
|         |   | m |   |            |      |          | @ |               |
|         |   | a |   |            |      |          | m |               |
|         |   | i |   |            |      |          | a |               |
|         |   | l |   |            |      |          | i |               |
|         |   | . |   |            |      |          | l |               |
|         |   | a |   |            |      |          | . |               |
|         |   | r |   |            |      |          | a |               |
|         |   | c |   |            |      |          | r |               |
|         |   | . |   |            |      |          | c |               |
|         |   | n |   |            |      |          | . |               |
|         |   | a |   |            |      |          | n |               |
|         |   | s |   |            |      |          | a |               |
|         |   | a |   |            |      |          | s |               |
|         |   | . |   |            |      |          | a |               |
|         |   | g |   |            |      |          | . |               |
|         |   | o |   |            |      |          | g |               |
|         |   | v |   |            |      |          | o |               |
|         |   | ] |   |            |      |          | v |               |
|         |   | { |   |            |      |          | ] |               |
|         |   | . |   |            |      |          | { |               |
|         |   | u |   |            |      |          | . |               |
|         |   | n |   |            |      |          | u |               |
|         |   | d |   |            |      |          | n |               |
|         |   | e |   |            |      |          | d |               |
|         |   | r |   |            |      |          | e |               |
|         |   | l |   |            |      |          | r |               |
|         |   | i |   |            |      |          | l |               |
|         |   | n |   |            |      |          | i |               |
|         |   | e |   |            |      |          | n |               |
|         |   | } |   |            |      |          | e |               |
|         |   |   |   |            |      |          | } |               |
+---------+---+---+---+------------+------+----------+---+---------------+
| **Pr    |   |   |   |            | **Au |          |   |               |
| incipal |   |   |   |            | thor |          |   |               |
| Inves   |   |   |   |            | ized |          |   |               |
| tigator |   |   |   |            | I    |          |   |               |
| Signa   |   |   |   |            | nsti |          |   |               |
| ture:** |   |   |   |            | tuti |          |   |               |
|         |   |   |   |            | onal |          |   |               |
|         |   |   |   |            | Offi |          |   |               |
|         |   |   |   |            | cial |          |   |               |
|         |   |   |   |            | Sign |          |   |               |
|         |   |   |   |            | atur |          |   |               |
|         |   |   |   |            | e:** |          |   |               |
+---------+---+---+---+------------+------+----------+---+---------------+
| **      |   |   |   |            | *    |          |   |               |
| Date:** |   |   |   |            | *Dat |          |   |               |
|         |   |   |   |            | e:** |          |   |               |
+---------+---+---+---+------------+------+----------+---+---------------+

+----------+---+---+---+----------------+-------------+----------+---+---+
| **Co-    |   |   |   |                |             |          |   |   |
| Investig |   |   |   |                |             |          |   |   |
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TABLE OF CONTENTS

LIST OF ACRONYMS i

ABSTRACT 1

1 BACKGROUND, OBJECTIVES AND JUSTIFICATION 1

2.  SUMMARY OF CURRENT RESEARCH TASKS 2

3.  EXAMPLE RESEARCH RESULTS 3

> 3.1 Satellite Validation 3

2.  Closure Among Suborbital Results 6

3.  Aerosol Absorbing Fraction from Radiative Flux and AOD Spectra 11

4.  Aerosol Optical Modeling 12

5.  Tests of Chemical Transport Models 12

6.  Regional Forcing from Satellite and Suborbital Results 13

7.  AATS Maintenance and Upgrades 15

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4.  PROPOSED RESEARCH 15

> 4.1 Integrated Analyses of Prior Experiments 15
>
> 4.2 Potential Future Experiments and Preferred Aircraft 18

3.  Instrument Maintenance and Enhancement 19

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5.  REFERENCES 20

6.  BUDGET 25

7.  STAFFING, RESPONSIBILITIES,

AND VITAE 28

> 7.1 Roles of PI and Co-Is 28
>
> 7.2 Collaborations 28
>
> 7.3 Vitae 28

8 CURRENT AND PENDING SUPPORT 35

**ACRONYMS**

  --------- ------------------ ----------------------------------------------------
  AATS-6                       6 (14)-channel Ames Airborne Tracking Sunphotometer
  (14)                         

  ACE                          Aerosol Characterization Experiment

  ACIP                         Aerosol-Climate Interactions Program

  ADAM                         Asian Dust Above Monterey

  AERONET                      Aerosol Robotic Network

  AMMA                         African Monsoon Multidisciplinary Analyses

  AOD                          Aerosol Optical Depth

  ARM                          Atmospheric Radiation Measurement

  ATSR                         Along Track Scanning Radiometer

  AVHRR                        Advanced Very High Resolution Radiometer

  CALIPSO                      Cloud-Aerosol Lidar and Infrared Pathfinder
                               Satellite Observations

  CARMA                        Community Aerosol and Radiation Model for
                               Atmospheres

  CCRI                         Climate Change Research Initiative

  CCSP                         Climate Change Science Program

  CERES                        Clouds and the Earth's Radiant Energy System

  CFORS                        Chemical Weather FORecasting System

  CIRPAS                       Center for Interdisciplinary Remotely Piloted
                               Aircraft Studies

  CTM                          Chemical Transport Model

  CWV                          Column Water Vapor

  DISORT                       DIScrete Ordinates Radiative Transfer

  EOS                          Earth Observing System

  GCM                          General Circulation Model

  GEWEX                        Global Energy and Water Cycle Experiment

  GLAS                         Geosciences Laser Altimeter System

  GMS                          Geostationary Meteorological Satellite

  GOCART                       Global Ozone Chemistry Aerosol Radiation Transport

  GOES                         Geostationary Operational Environmental Satellite

            INTEX-NA           Intercontinental Chemical Transport Experiment-North
                               America

  ISCCP                        International Satellite Cloud Climatology Program

  ITCT                         Intercontinental Transport and Chemical
                               Transformation

  MATCH                        Model of Atmospheric Transport and CHemistry

  MISR                         Multi-angle Imaging Spectro-Radiometer
  --------- ------------------ ----------------------------------------------------

  ------------------ ----------------------------------------------------
  MODIS              Moderate-resolution Imaging Spectroradiometer

  NAAPS              Navy Aerosol Analysis and Prediction System

  NACIP              National Aerosol-Climate Interactions Program

  NACP               North American Carbon Program

  NAS                National Academy of Sciences

  OMI                Ozone Measuring Instrument

  PBL                Planetary boundary layer

  PRIDE              Puerto RIco Dust Experiment

  PSAP               Particle Soot Absorption Photometer

  SAFARI             Southern African Regional Science Initiative

  SAL                Sahara Air Layer

  SCAR-B             Smoke, Clouds, Aerosols and Radiation-Brazil

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

  SGP                Southern Great Plains

  SSA                Single Scattering Albedo

  SSFR               Solar Spectral Flux Radiometer

  TARFOX             Tropospheric Aerosol Radiative Forcing Observational
                     Experiment

  TOMS               Total Ozone Mapping Spectrometer
  ------------------ ----------------------------------------------------

**Satellite-Sunphotometer Studies of Aerosol-Chemistry-Climate
Coupling**

**Abstract**. We propose to conduct research, as a renewal of our
current Interdisciplinary Science and Radiation Sciences tasks, that
addresses the following broad questions: (1) How are aerosols from
natural and anthropogenic sources affecting atmospheric radiation and
the climate, and (2) What are the effects of regional pollution on the
global atmosphere? We specifically will focus on the issues of (a) What
are the optical properties of aerosols containing black carbon and other
constituents, and how do these optical properties relate to their
physico-chemical makeup, including their mixing state? (b) How well can
these aerosols be measured from space, and what can be done to improve
space-based retrievals? (c) How well are these aerosols represented in
chemical-transport models? (d) What are the best ways to combine
satellite and suborbital data in assessing aerosol and trace gas
radiative-climatic effects?

Our approach features integrated analyses of data from field studies
that coordinate measurements from space, aircraft, and the surface, in
conjunction with models of aerosols and radiation. We emphasize the use
of airborne sunphotometry as a unique link between space-based
retrievals and a diversity of suborbital measurements. These include in
situ, vertically resolved measurements of radiative fluxes and of
aerosol physico-chemical microproperties, as well as remote sensing by
lidar and surface-based radiometers. Past experiments planned for
analysis include SAFARI-2000, ACE-Asia (2001), and CLAMS (2001; see
acronyms list on p. i). Planned and potential future experiments include
ADAM (2003), INTEX-NA/ITCT 2K4 (2004), and AMMA (2005), as well as
experiments to study Asian aerosols from biomass burning and other
sources. The proposed research will support concept development for such
missions, help prepare the community for participation, and, depending
on mission dates, provide integrated data analyses.

Expected outcomes from the research include: (1) Tests of retrieval
accuracy for satellite sensors such as MISR, MODIS, OMI, and SeaWiFS on
satellites such as Terra, Aqua, Aura and Orbview, along with
explanations of discrepancies and/or recommendations for improvements,
(2) Models of black carbon-containing aerosols based on closure studies
that integrate in situ sampling with remote measurements, (3) Tests of
aerosol chemical-transport models (CTMs), including their predicted
vertical distributions, (4) Implications of realistic, composite aerosol
models for remote sensing algorithms and aerosol radiative effects, and
(5) Regional assessments of aerosol radiative effects based on inputs
that combine the salient features of satellite and suborbital
measurements.

**1 BACKGROUND, OBJECTIVES AND JUSTIFICATION**

As noted by numerous studies and assessments (e.g., IPCC, 2001; NAS,
2001), atmospheric aerosols continue to be one of the largest sources of
uncertainty in understanding current and past climates and in predicting
the future climate. This uncertainty results from the great variety and
complexity of aerosol types, from their highly variable spatiotemporal
distributions, and from the variety of pathways by which aerosols can
affect the climate. These pathways include not only aerosol direct
effects on the scattering and absorption of radiation, but indirect
effects caused by aerosol roles in cloud microphysics, and "semi-direct"
effects caused by aerosol modification of atmospheric heating,
temperature profiles, convection, and large-scale horizontal transport
(e.g., Chameides and Bergin, 2002; Kaufman et al., 2002; Lelieveld et
al., 2002; Menon et al., 2002). Many of these pathways can affect
precipitation, and thus aerosols are intimately linked to the
hydrological cycle (e.g., Rosenfeld, 2000; Rotstayn et al., 2000).

As a result of these large and multifaceted uncertainties, the US
Government's Climate Change Research Initiative (CCRI) and the proposed
National Aerosol-Climate Research Interactions Program (NACIP) have
called for research to improve our understanding of the climatic effects
of aerosols and their interplay with radiatively active gases. This call
is echoed by NRA-02-OES-06, which specifically solicits proposals for
research on aerosol radiative-climatic effects---in particular research
that builds on results of the NASA/GEWEX Global Aerosol Climatology
Project (GACP), supports the strategy of NACIP, and responds to issues
identified by IPCC (2001) and NAS (2001). An issue highlighted by the
NRA is the role of black carbon (BC)-containing aerosols in climate
change, and the need to develop better techniques for measuring them and
representing them in satellite retrieval algorithms and in models
describing their global distributions and effects. Also solicited by the
NRA are proposals for analyses of existing field experiment data sets,
with analyses of integrated satellite-suborbital data favored.

This proposal requests funding to renew our current tasks in the
Interdisciplinary Science (IDS) and Radiation Sciences programs (see
Section 2 for current task descriptions). In accord with the call in
NRA-02-OES-06, the objective of the proposed research is to address the
following broad questions: (1) How are aerosols from natural and
anthropogenic sources affecting atmospheric radiation and the climate,
and (2) What are the effects of regional pollution on the global
atmosphere? We specifically will focus on the issues of (a) What are the
optical properties of aerosols containing black carbon and other
constituents, and how do these optical properties relate to their
physico-chemical makeup, including their mixing state? (b) How well can
these aerosols be measured from space, and what can be done to improve
space-based retrievals? (c) How well are these aerosols represented in
chemical-transport models? (d) What are the best ways to combine
satellite and suborbital data in assessing aerosol and trace gas
radiative-climatic effects?

Section 3 describes results from the IDS and Radiation Sciences tasks we
seek to renew. Also described are the approaches and conceptual
framework of those tasks, which set the stage for the approaches to be
used in the proposed research. Section 4 outlines the proposed research,
including data sets from completed field studies and summaries of
planned experiments.

**2 SUMMARY OF CURRENT RESEARCH TASKS**

**2.1 IDS Task: Satellite-Sunphotometer Studies of Aerosol, Water Vapor,
and Ozone Roles in Climate-Chemistry-Biosphere Interactions.** NASA RTOP
291-01-91-45, Interdisciplinary Science (IDS) Program, 2/2000-12/2002,
\$760,000.

# This IDS award has supported modeling and integrated analyses of suborbital and satellite data acquired primarily in three international multiplatform field campaigns: PRIDE (conducted in 2000), SAFARI 2000, and ACE Asia (2001). To date this task has produced 13 journal publications (Bergstrom et al., 2002b; Gatebe et al., 2002; Levy et al., 2002; Livingston et al., 2002; Magi et al., 2002; McGill et al., 2002; Pilewskie et al., 2002a; Reid et al., 2002a,b; Schmid et al., 2001, 2002; Wang et al., 2002a,b; Xu et al., 2002) and an additional submission (Colarco et al., 2002) describing results from these three campaigns. Examples of these results are shown in Section 3.

**2.2 Radiation Sciences Task: Improved Exploitation of Field Data Sets
to Address Aerosol Radiative-Climatic Effects and Development of a
Global Aerosol Climatology.** NASA RTOP 622-44-75-10, Global Aerosol
Climatology Program (GACP), 10/1998-3/2003, \$777,000.

This GACP award has focused primarily on integrated analyses of data
sets from TARFOX (conducted in 1996) and ACE-2 (1997), plus initial
analyses of data from CLAMS (2001). Results are described in 12 journal
publications led by the Ames sunphotometer-satellite team (Bergstrom and
Russell, 1999; Bergstrom et al., 2002a; Livingston et al., 2000;
Redemann et al., 2000a,b, 2001; Russell and Heintzenberg, 2000; Russell
et al., 1999a,b; 2002; Schmid et al., 1999, 2000), plus 12 others we
coauthored (Collins et al., 2000; Durkee et al., 2000; Ferrare et al.,
2000a,b; Flamant et al., 2000; Gasso et al., 2000; Hartley et al., 2000;
Ismail et al., 2000; Pilewskie et al., 2000; Tanre et al., 1999;
Veefkind et al., 1999; Welton et al., 2000). Examples of these results
are shown in Section 3.

**3 EXAMPLE RESEARCH RESULTS**

Figures 1 and 2 show schematically the scientific motivation and overall
approach for our IDS and GACP tasks. As indicated by Figure 1, aerosols
caused 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). 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. Two gas-phase constituents, water vapor
and ozone, are also relevant to these tasks, because they interact with
aerosols both chemically and physically, and they are themselves major
players in the Earth's radiation budget. All three
constituents---aerosols, water vapor, and ozone---can be retrieved
quantitatively from spaceborne measurements. However, retrieval accuracy
is still being determined, because it depends strongly on constituent
type, measurement conditions (e.g., over land vs. water, in or out of
sun glint, in or out of cirrus or other cloud fields), and spaceborne
measurement technique (e.g., multiangle, multiwavelength, polarization,
nadir- vs. limb-viewing, passive vs. active, etc.).

The three constituent types can also be measured by airborne
sunphotometry. Our IDS and Radiation Science tasks have emphasized the
use of airborne sunphotometry as a unique link between space-based
retrievals and a diversity of suborbital measurements. These include in
situ, vertically resolved measurements of radiative fluxes and of
aerosol physico-chemical microproperties, as well as remote sensing by
lidar and surface-based radiometers. A key theme has been combining
satellite and suborbital measurements to develop more complete and
realistic descriptions of aerosol and gas properties and effects.

Figure 2 illustrates the coordination of satellite and suborbital
measurements used in many field studies---e.g., TARFOX, ACE-2, PRIDE,
SAFARI 2000, ACE-Asia, CLAMS---to maximize the synergy between the
different types of measurements. Following such coordinated
measurements, the analysis challenge has been to capture the salient
results from each type of measurement in developing a sufficiently
accurate and complete description of aerosol and trace gas properties
and effects in the study region. Successful analyses have included not
only testing (and sometimes improving) the accuracy of
satellite-retrieved products, but also combining those products with
information from suborbital measurements in models to describe regional
aerosol radiative effects.

# In the remainder of this section we show illustrative results, as an introduction to the proposed research.

1.  **Satellite Validation**

    During the experiments analyzed in our IDS and Radiation Sciences
    tasks (TARFOX, ACE-2, PRIDE, SAFARI-2000, ACE-Asia, and CLAMS),
    considerable effort was devoted to coordinating aircraft
    measurements with satellite overpasses. The list of satellite
    sensors includes AVHRR, GMS-5, GOES-8 imager, MISR, MODIS, SeaWiFS,
    TOMS and ATSR- 2. The aircraft measurements include aerosol optical
    depth spectra measured by an Ames Airborne Tracking Sunphotometer
    (AATS-14

    or AATS-6; e.g., Matsumoto et al., 1987). When measured on transects
    flown near the land or ocean surface, such optical depth spectra are
    useful for validating products from the satellite sensors. Here we
    show a representative sampling of such comparisons we have completed
    to date.

    **MODIS Dust Retrievals in PRIDE**. Figure 3 shows a scatter plot
    comparing aerosol optical depths (AOD) at four wavelengths, as
    retrieved by MODIS and as measured by AATS-6 flying near the ocean
    surface in the MODIS scene. All measurements were made in the Puerto
    Rico Dust Experiment (PRIDE). Data points with AOD\>0.2 are from
    conditions dominated by Saharan dust transported to the Caribbean
    (Reid et al., 2002a,b). For the cases with little or no dust
    (AOD\<0.2), MODIS and AATS-6 values are within \~1 error bar of the
    1:1 line. In dust-dominated conditions (AOD\>0.2), this is also true
    for AOD at wavelength 870 nm. However, at the shorter wavelengths,
    MODIS-retrieved AOD systematically exceeds the AATS-6 values. Thus,
    in dust-dominated conditions the slope of AOD vs. wavelength is
    steeper in MODIS-retrieved spectra than in AATS-6 spectra. This

![](media/image2.wmf){width="6.0in" height="3.5416666666666665in"}

**Figure 1.** Schematic of the scientific motivation and overall
approach for our current IDS and Radiation Science tasks.

![](media/image3.wmf){width="6.0in" height="3.875in"}

**Figure 2.** Schematic of the approach used in field experiments that
coordinate a variety of suborbital measurements, including airborne
sunphotometry, with satellite overflights. Example of size-resolved
composition data is from Wang et al. (2002a). Electron microscope (EM)
image of particles is courtesy of James Anderson, Arizona State
University. EM image is 7 μm wide.

![](media/image2.wmf)

**Figure 3**. Scatter plot comparing AODs retrieved by MODIS to those
measured by AATS-6 in PRIDE (Livingston et al., 2002).

is shown explicitly in Figure 4, which plots the same data as spectra of
AOD vs. wavelength.

The likely cause of this slope difference is dust nonsphericity, which
causes the MODIS retrieval to substitute more small mode aerosol for
nonspherical large mode dust (Remer et al., 2002). An updated MODIS
algorithm that adds nonspherical phase functions is being developed to
address this.

**MODIS Retrievals in SAFARI 2000**. MODIS-AATS comparisons in SAFARI
2000 helped confirm that the biomass smoke single scattering albedo
(SSA) originally used in MODIS AOD retrievals (SSA \~0.9, based on
SCAR-B) produced retrieved AODs \< correlative AODs (see, e.g., the
points marked MODIS 9:02 UT in Figure 5. Adopting a new SSA (\~0.85) has
now produced retrieved AODs (V4 MODIS in Figure 5) that agree with AATS,
AERONET, and other AODs in regions with strong biomass burning such as
in Zambia.

> Other AATS-14 measurements in SAFARI 2000 (not shown for brevity)
> provided the first validation of MODIS-retrieved AODs at wavelengths
> 1.2 and 1.6 μm over water (Schmid et al., 2002).

![](media/image3.wmf){width="3.0972222222222223in"
height="8.563194444444445in"}

**Figure 4**. MODIS and AATS spectra for the 7 cases in Figure 3
(Livingston et al., 2002).

![](media/image2.wmf)

**Figure 5**. Comparison of AOD spectra from MODIS retrievals and
AATS-14 measurements in SAFARI 2000 during a dense haze episode from
biomass burning.

![](media/image3.wmf){width="3.0833333333333335in"
height="2.5277777777777777in"}

> **Figure 6.** Comparison of AOD spectra from MISR retrievals and
> AATS-14 measurements in SAFARI 2000.

**MISR Retrievals in SAFARI-2000**. MISR-AATS comparisons in SAFARI-2000
(e.g., Figure 6) showed that a model including small, spherical,
non-absorbing particles needed to be restored to the MISR retrieval. (It
had been deleted early in the mission to reduce computer resource
requirements.) As shown in Figure 6, before this model was restored,
neither the best-fit nor the 2^nd^ best-fit MISR model was able to match
both the slope and magnitude of the AATS-14 AOD spectrum.

**SeaWiFS Retrievals in ACE-Asia**. Comparisons (e.g., Figure 7) between
AATS measurements and SeaWiFS retrieved AOD yield good agreement if the
new 4-wavelength Hsu et al. (2002) algorithm is used, but disagreement
if using the standard SeaWiFS algorithm.

**MISR Retrievals in ACE-Asia**. MISR-AATS comparisons in ACE-Asia (not
shown for brevity) confirmed that early MISR-derived AODs were skewed
high for some low-light-level scenes. Subsequent experiments
demonstrated that scattered light played a key role in this phenomenon,
and led to a revision of the MISR low-light-level calibration (that
significantly affects MISR-derived AOD over dark water) (R. Kahn,
personal communication).

2.  **Closure Among Suborbital Measure- ments**

    Closure studies test the consistency of different measurements that
    are linked by one or more models. Because the linking models (e.g.,
    of aerosol growth in humidity, of light scattering by mixed
    aerosols) are often used as components of the chemical transport
    models or general circulation models that predict aerosol effects on
    climate, closure studies provide important assessments of both the
    measurements and the models that undergird our current understanding
    of aerosol effects on climate.

An important class of closure studies addresses the question: \"Can in
situ measurements of aerosol properties account for the solar beam
attenuation (extinction) by an aerosol layer or column?\" Such closure
studies have revealed important insights about aerosol sampling and
inadvertent modification in such previous experiments as TARFOX (Hegg et
al., 1997; Hartley et al. 2000), ACE-2 (Collins et al., 2000; Schmid et
al., 2000) and SAFARI 2000 (Magi et al., 2002).

Key to these studies is the measurement of aerosol optical depth and
columnar water vapor with an Ames Airborne Tracking Sunphotometer
(AATS-14 or AATS-6). This is because inlet effects (e.g., loss or
enhancement of large particles, shrinkage by evaporation of

![](media/image4.wmf){width="4.807638888888889in"
height="3.613888888888889in"}

**Figure 7.** Comparison of spectral aerosol optical depth on April 12,
2001 between AATS-14 and SeaWiFS, using standard and Hsu et al. (2002)
algorithms.

![](media/image5.wmf){width="4.831944444444445in"
height="3.6256944444444446in"}

**Figure 8.** Left panel: Aerosol optical depth profiles at 13
wavelengths from 354 to 1558 nm calculated from AATS-14 measurements
acquired during an aircraft ascent south of Korea on 17 April 2001
during ACE-Asia. Right panel: Corresponding aerosol extinction profiles
derived by differentiating spline fits (dashed lines in left panel) to
the optical depth profiles.

water, organics, or nitrates) and filter effects are avoided. During
ACE-Asia, AATS-14 measured the transmission of the direct solar beam at
14 discrete wavelengths λ, from 354 to 1558 nm, and AATS-6 measured at 6
discrete wavelengths between 380 and 1020 nm. From these direct solar
beam transmission measurements we derived spectral aerosol optical
depths AOD(λ), columnar water vapor CWV, and columnar ozone. Flying at
different altitudes over a fixed location allows derivation of AOD(λ) or
CWV in a given layer. Data obtained in vertical profiles allows
derivation of spectral aerosol extinction *E~a~*(λ) (see Figure 8) and
water vapor density *ρ*~w~.

Measuring solar beam attenuation by an AATS on the same aircraft as in
situ sensors allows a close match in the aerosol layers described by the
attenuation and in situ measurements (see, e.g., Figure 2). Such a match
allows the best-defined comparison between attenuation and in situ
results. It avoids the ambiguity that occurred in previous experiments
when the only sunphotometer was on the ground and thus provided no
information on what fraction of column optical depth was above the
aircraft's maximum sampling height. An example from ACE-Asia where the
in situ extinction is computed as the sum of scattering (from humidified
nephelometry) and absorption (from a PSAP instrument) is shown in Figure
9.

Figure 10 shows an example result from an ACE-Asia closure study (Wang
et al., 2002a) that compares aerosol extinction from AATS-14 with values
calculated from Mie theory using measured size distributions and
size-resolved composition (used to determine the complex refractive
indices). In the uppermost layer, the underestimate of Mie-predicted
extinction compared to the AATS-14 result is attributed to nonspherical
dust particles there, which are undersized by the in situ mobility
analyzer (Wang et al., 2002a).

Our extinction closure analyses have also included comparisons with the
numerous lidars deployed during TARFOX, ACE-2, SAFARI-2000, and ACE-Asia
on land, ships and aircraft. Figure 10 shows an example using the
ACE-Asia ship lidar (e.g., Welton et al., 2001) during the same flight
as shown in Figures 8 and 9.

AATS-6 and AATS-14 measure the overlying column water vapor (CWV) using
a channel in the 940-nm water vapor absorption band. Vertical
differentiation of AATS CWV profiles in aircraft ascents or descents
yields profiles of water vapor concentration. Our closure studies have
included many comparisons between the AATS water vapor results and those
from a variety of other measurement techniques (e.g., Schmid et al.,
2000, 2001). Figure 11 shows examples for AATS-14 in ACE-Asia.

Initial results from CLAMS were presented at the AGU Fall 2001 and
Spring 2002 meetings and at the AMS 2002 Radiation Conference. The talks
included data measured by AATS-14 aboard the University of Washington
CV-580, plus comparisons to other suborbital measurements obtained using
(i) the AERONET sun/sky radiometer at the Chesapeake Lighthouse, (ii)
the MODIS Airborne Simulator (MAS), and (iii) in situ measurements
aboard the UW CV-580. Having examined the agreement of the various
suborbital aerosol measurement techniques, further comparisons were
presented of suborbital AOD measurements to AOD retrievals using data
acquired by MISR and MODIS aboard the Terra satellite. To date (December
2002), our participation in CLAMS has resulted in 12 conference
publications, some of which we plan to develop into peer-reviewed
journal papers as part of the proposed research (see Section 4).

Our closure studies have also included comparisons of aerosol absorption
and single scattering albedo (SSA) derived by different techniques. In
Russell et al. (2002) we compared aerosol absorption derived by diverse
techniques in TARFOX and ACE-2, and found that absorption derived from
broadband solar irradiance measurements (\~300-700 and 300-4000 nm) was
larger than that derived from other techniques. As shown in the next
section, using spectrally resolved irradiance measurements can yield
absorption spectra and, when combined with AOD spectra, SSA spectra.

![](media/image6.wmf){width="4.831944444444445in"
height="3.6256944444444446in"}

**Figure 9.** Aerosol optical depth (left) and extinction (right)
profile at 550 nm measured by AATS-14 and computed as the sum of
scattering (from humidified nephelometry) and absorption (PSAP
instrument) during aircraft ascent shown in Figure 8.

![](media/image7.png){width="4.477083333333334in"
height="3.9944444444444445in"}

**Figure 10.** Comparison of aerosol extinction derived from AATS-14
measurement, aerosol size distributions, and lidar measurements on R/V
Ron Brown during the ascent shown in Figure 8 (Wang et al., 2002a).

![](media/image8.wmf){width="5.583333333333333in"
height="7.972222222222222in"}**Figure 11**. Comparison of water vapor
measurements on the Twin Otter in ACE-Asia by AATS-14 and in situ
sensors. (a-l) Representative vertical profiles. (m) Comparison of layer
water vapor for 26 profiles. Error bars are based on horizontal distance
spanned by a profile, combined with average horizontal variability of
CWV in ACE-Asia flights. (n) Comparison of water vapor density for the
26 profiles.

3.  **Aerosol Absorbing Fraction from Radiative Flux and AOD Spectra**

Results in this section are from a collaboration with Dr. Peter
Pilewskie of NASA Ames, who was funded by a separate task of the
Radiation Sciences Program. Dr. Pilewskie flew Solar Spectral Flux
Radiometers (SSFRs) on the same aircraft as our AATS-6 or AATS-14 in
PRIDE, SAFARI-2000, and ACE-Asia. The SSFRs measured downwelling and
upwelling solar radiative flux spectra, from which the net (downwelling
minus upwelling) flux spectrum was derived. The difference between net
flux spectra at two altitudes is the absorption spectrum of the
atmospheric layer (gases and particles) between the two altitudes.
Combining this SSFR-measured absorption with AATS-measured AOD in a
radiative tranfser model yields spectra of SSA in the layer.

Figure 12 illustrates this type of analysis for an ACE-Asia flight of
the Twin Otter, which included level legs at altitudes 43 and 2277 m.
The measured absorption spectrum (blue curve in frame a) is shown in
frame b as a fraction of the downwelling radiation at the upper level.
Frame c shows AOD spectra measured by AATS-14 at the same altitudes. The
radiative

![](media/image9.wmf){width="3.1902777777777778in"
height="2.5069444444444446in"}

**Figure 12**. (a) Measured and modeled absorption spectra for the
ACE-Asia profile flown on Twin Otter Flight RF07, 12 April 2001. (b) As
in (a), expressed as fraction of downwelling flux on 2277 m leg. (c) AOD
spectra measured simultaneously on the same aircraft.

transfer model of Bergstrom et al. (2002b) used these measured AOD
spectra with an assumed wavelength-independent SSA to calculate the
model absorption spectra (red curves) shown in frames a and b. Note that
this assumed SSA clearly underestimates absorption for wavelengths \<600
nm.

![](media/image10.wmf){width="3.120833333333333in"
height="2.6527777777777777in"}

**Figure 13**. Aerosol single scattering albedo spectra derived from the
measured flux and AOD spectra in Figure 12.

![](media/image11.wmf){width="3.2979166666666666in"
height="2.5215277777777776in"}

**Figure 14**. Derived dust single scattering albedo from PRIDE (blue
curve) and ACE-Asia (green curve). Five aerosol models are shown for
comparison (Quijano et al., 2000; Ackerman and Cox, 1988)

Adjusting model SSA to produce a match between modeled and measured
absorption yields the SSA values shown in Figure 13 with the wavelength
regions dominated by gaseous absorption removed. Figure 14 compares the
SSA spectra derived for this ACE- Asia case and an analogous PRIDE case
to published results for Saharan, Afghan and SW Asian dusts (Quijano et
al., 2000; Ackerman and Cox, 1988).

4.  **Aerosol Optical Modeling**

    During the course of our IDS and Radiation Sciences tasks we have
    developed and used a variety of aerosol optical models in an effort
    to capture the salient features of aerosol measurements in a form
    that can be used in radiative transfer modeling. Here we cite two
    examples.

    ![](media/image12.wmf){width="3.1666666666666665in" height="2.5in"}

    **Figure 15.** Difference in single scattering albedo estimates
    (solid), absorption humidification factor (short-dashed) and
    absolute value of the single scattering albedo (long-dashed) at 550
    nm for a mono-modal log-normal size distribution with a geometric
    mean radius of 0.06 µm and a geometric standard deviation of 1.5.
    Highlighted in the gray box is the area for which the single
    scattering albedo is greater than or equal to 0.75 (lower limit of
    observed values) \[Redemann et al., 2001)\].

    In Redemann et al. (2001) we used a core/shell model of internally
    mixed soot/sulfate particles to show that, when aerosol black carbon
    (BC) occurs as an inclusion in a sulfate shell, humidity increases
    can increase absorption. This occurs because the shell focuses the
    electromagnetic field on the BC, and shell growth in rising humidity
    increases the focused field strength. Calculations of this effect
    for realistic size distributions, humidities, and BC/sulfate ratios
    show that, for the range of SSA found in TARFOX and ACE-2 (i.e.,
    0.85**≤**ω~midvis~**≤**0.99), the frequently used assumption that
    absorption is humidity-independent may overestimate SSA by \~0.02
    (more for smaller dry particles in narrow size distributions, less
    for larger particles in broad distributions). This effect is
    illustrated in Figure 15.

    In Bergstrom et al. (2002a) we compared the wavelength dependence of
    aerosol absorption measured in TARFOX with theoretical predictions
    for black carbon (BC) particles. We found that the measured λ^-1^
    dependence of absorption was consistent with model calculations of
    absorption by small BC particles with little wavelength dependence
    of real and imaginary refractive indices.

5.  **Tests of Chemical-Transport Models**

    International comparisons (e.g., Penner et al., 2001) of the
    chemical-transport models (CTMs) that predict aerosol spatial
    distributions show that vertical distributions often differ markedly
    from model to model. Hence, the vertical profiles of AOD and
    extinction measured by our airborne sunphotometers (AATS-6 and -14)
    can provide a key performance test for such CTMs. We have
    participated in such tests of the models GOCART (Chin et al., 2001,
    2002), CARMA/MATCH (Colarco et al., 2002), and MATCH (Collins, 2002;
    Rasch and Collins, 2001).

    Figure 16 shows examples of such comparisons (Colarco et al., 2002)
    between Sahara dust AOD profiles simulated by CARMA/MATCH and AOD
    profiles measured by AATS-6 in the Puerto Rico Dust Experiment
    (PRIDE; see Reid et al., 2002a,b; Livingston et al., 2002). In the
    first case shown (June 28, 2000, top frame), the AOD profile
    measured by AATS-6 shows a decrease from near the surface to \~4 km
    altitude, with the steepest AOD decrease in the PBL (\~0 to \~1.4
    km). Since the vertical rate of decrease of AOD is aerosol
    extinction, the AATS AOD profile therefore shows the largest aerosol
    extinction in the PBL, with less above. Other PRIDE measurements for
    this case indicate that most of the aerosol extinction, both in the
    PBL and above, was from dust. PRIDE analyses identify this as a case
    of low-level transport of Saharan dust to the Caribbean (Reid et
    al., 2002a,b), which was typical early in the PRIDE period (June 28
    -- July 24, 2000). In contrast to the data, two of the model
    profiles (0% and 10% scavenging) show constant or nearly constant
    AOD in the PBL (0 to \~1.2 km), indicating little or no dust there,
    but steadily decreasing AOD from 1.2 km to 5.5 km, indicating
    significant dust extinction aloft. Thus these modeled dust profiles
    show most dust above the PBL, indicating a case of predominant
    transport in an elevated Sahara Air Layer (SAL). The model
    simulations with \<100% scavenging in the precipitating part of
    clouds (see labels in figure) do show some dust in the PBL (i.e.,
    some AOD decrease with height there), but none of the simulations
    for this case reproduces the measured vertical profile of AOD very
    well.

    ![](media/image13.wmf){width="3.1527777777777777in"
    height="4.986111111111111in"}

    **Figure 16.** Comparison of AOD profiles measured by airborne
    sunphotometer (AATS-6) and computed by the CARMA/MATCH model. Model
    AOD profiles are labeled by the assumed wet scavenging within the
    precipitating part of clouds (Colarco et al., 2002).

    Better agreement between model and measurements is shown in the
    lower frame (July 5, 2000). This is another case of low-level dust
    transport. Both AATS-6 and the model show AOD decreasing steadily
    from the surface with height. The model profile with 10% scavenging
    in the precipitating part of clouds matches the AATS-6 AOD well from
    the surface to \~1 km. Above that height, model calculations with
    more than 10% scavenging produce better agreement with AATS AOD.

    Comparisons between GOCART and AATS-14 for Asian aerosols measured
    in ACE-Asia have been presented by Chin et al. (2001, 2002).
    Comparisons between MATCH simulations and AATS measurements in
    ACE-Asia are also underway.

6.  **Regional Forcing Assessments by Combining Satellite and Suborbital
    Results**

Our first regional assessment of aerosol radiative forcing (Bergstrom
and Russell, 1999) combined single-wavelength seasonal AOD maps of the
North Atlantic region with aerosol intensive properties derived from the
TARFOX and ACE-2 field programs. The AOD maps were derived by Husar et
al. (1997) from AVHRR reflectances; an example is shown in Figure 17a.
The aerosol intensive properties included optical depth wavelength
dependence across the solar spectrum, single scattering albedo,
hemispheric upscatter fraction, and relative vertical profile, all
synthesized from suborbital measurements by aircraft and ground sites
(including lidars). The satellite and suborbital inputs were combined in
a radiative transfer model (Bergstrom et al., 2002b) to derive maps of
cloud-free and all-sky radiative forcing; an example for cloud-free
conditions is shown in Figure 17b. As shown in Bergstrom and Russell
(1999), cloud effects, estimated from ISCCP data, greatly reduce the
regional annual average, because of the large cloud fractions in the
North Atlantic.

More recently we have been using ACE-Asia satellite and suborbital data
to estimate the radiative impact of the Asian Pacific plume of desert
dust and pollution, which is one of the world's most climatically
significant aerosols.

![](media/image14.png){width="6.747222222222222in"
height="3.089583333333333in"}

**Figure 17.** (a) June-August mean AOD at 500 nm derived from AVHRR
radiances by Husar et al. (1997). (b) 24h-average, cloud-free direct
shortwave aerosol radiative forcing at the tropopause derived from the
total aerosol optical depth map in (a). The radiative calculation
(Bergstrom and Russell, 1999) assumes an aerosol model based on
suborbital measurements in TARFOX and ACE-2. The choice of SSA shown
here, ω~a~=0.9, is based on radiative flux measurements; other
measurements yielded larger SSA (ω~a~\~0.92 to 0.98) (Russell et al.,
2002a). Bergstrom and Russell (1999) show results for ω~a~=1 and
ω~a~=0.9.

![](media/image15.jpeg){width="6.751388888888889in"
height="2.8048611111111112in"}**Figure 18.** (a) April 2001 monthly mean
AOD at 865 nm derived from SeaWiFS radiances using the algorithm of Hsu
et al. (2002). (b) 24h-average, cloud-free direct shortwave aerosol
radiative forcing at the surface in Wm^-2^, derived from total aerosol
optical depth shown in (a). The radiative calculation assumes an aerosol
model of dust over pollution aerosols. The relative amounts of dust and
pollution aerosols are adjusted pixel-by-pixel to force model Angstrom
exponent to equal the Angstrom exponent derived from the 4-wavelength
SeaWiFS radiances by Hsu et al. (2002).

Our initial studies have used SeaWiFS-derived maps of aerosol optical
depth and Angstrom exponent, as well as in situ data obtained during
ACE-Asia (Russell et al., 2002b). Figure 18a shows a map of the April
2001 monthly mean aerosol optical depth at 865 nm, derived from
SeaWiFS-measured radiances using the algorithm of Hsu et al. (2002). We
computed corresponding maps of shortwave direct aerosol radiative
forcing of climate at the surface and at the top of the atmosphere (TOA)
by using the map in Figure 18a in conjunction with profiles of a model
dust over a model pollution aerosol, each constrained by ACE-Asia
measurements. We adjusted the relative amounts of dust and pollution in
each pixel to produce a model Angstrom exponent that matches the
SeaWiFS-retrieved Angstrom exponent in that pixel. An example result for
surface radiative forcing in cloud-free conditions is shown in Figure
18b.

In another approach, presented by Redemann et al. (2002b), we have made
more explicit use of ACE-Asia aerosol intensive properties derived in
closure-study vertical profiles and obtained a cloud-free surface
radiative forcing map similar to that in Figure 18b.

**3.7 AATS Maintenance and Upgrades**

Our Radiation Science task also provided limited but important support
for maintenance and upgrades to the Ames Airborne Tracking
Sunphotometers (AATS). Maintenance and upgrades for AATS-14 included
repairing a water leak, extending the wavelength range by adding a new
channel at wavelength 2.139 μm, removing the liquid cooling system
(thereby reducing the instrument weight by \~ 6 to 8 lbs), doubling the
power to the detector heaters to help maintain detector set point
temperature in extremely cold environments aloft, cleaning all filters
and detectors, cleaning seals, cleaning/lubricating bearings, and
procuring new optical filters to and replace those that have slowly
degraded over time. We calibrated the newly modified AATS-14 at Mauna
Loa Observatory in August and November 2002. We flew it on three DC-8
flights in September 2002 to test its performance and conduct an
airborne Langley calibration.

3.  **PROPOSED RESEARCH**

For the funding requested in Section 6 we propose to conduct the
following research over a period of three years.

1.  **Integrated Analyses of Prior Experiments**

We propose to apply methods similar to those described above to analyze
existing data sets from three experiments: ACE-Asia, CLAMS, and SAFARI
2000.

[Data Set 1. ACE-Asia (Spring 2001)]{.underline}. This set includes
measurements on the Twin Otter aircraft by AATS-14, SSFRs, and many in
situ sensors, plus measurements on the C-130 aircraft by AATS-6 and many
other sensors, all made in coordination with satellite overpasses. The
satellite data products include multiwavelength aerosol optical depth
(AOD) from sensors such as MISR, MODIS, SeaWiFS, AVHRR, and others. Also
available through collaborations are fields of AOD and other properties
predicted by the chemical-transport models (CTMs) CFORS, GOCART, MATCH,
and NAAPS (see list of acronyms on p. iii; see Section 3.5 for
references describing models).

The ACE-Asia results shown in Section 3 are a very small sample of
analyses already underway and possible in the future. Two special issues
of *J. Geophys. Res.* are planned for ACE-Asia, with papers due November
30, 2002 and \~six months later. Our team is leading two ACE-Asia
closure papers (Redemann et al., 2002c; Schmid et al., 2002b) and
participating in many more. This work is funded by our current IDS task
and a NOAA task, both of which will expire in the next several months.

We propose the following research on the ACE-Asia data set:

(1a) Complete, through final journal publication, the closure papers now
underway (2 led by our team, \~6 coauthored). These papers include a
detailed analysis of all available ACE-Asia profiles including
stratification of the closure results with respect to aerosol types,
relative humidity, flight pattern during profile and other factors. The
data include lidar extinction profiles and total column AOD from various
satellites.

(1b) Extend the derivations of SSA spectra from SSFR absorption spectra
and AATS AOD spectra (e.g., Section 3.3) to include more cases
representative of the variety of aerosols in ACE-Asia (e.g., dust,
pollution, sea salt, biomass burning, and various mixtures).

(1c) Participate in tests of the ACE-Asia performance of the CTMs GOCART
and MATCH by using AATS-6 and --14 data in vertical profiles and along
horizontal gradients. Complete this work through journal publications.

(1d) Contribute to the validation of CERES data by furnishing ACE-Asia
AATS-6 and -14 data, and data-use advice, to Dr. Sundar Christopher of
the University of Alabama in Huntsville. Dr. Christopher is proposing an
investigation that would, among other things, use biaxial scan mode
CERES data to develop angular models for estimating radiative fluxes and
thereby reduce uncertainties in aerosol radiative forcing.

(1e) Complete, through journal publication, the assessment of regional
radiative forcing by ACE-Asia aerosols. For this assessment the
following satellite-derived aerosol products are available:

• Maps of optical depth mode radius and the ratio of coarse to fine
particles from MODIS (<http://modis-atmos.gsfc.nasa.gov/MOD04_L2/>);

• Maps of aerosol optical depth from AVHRR
(<ftp://ssa.noaa.gov/patmosa/>)

• Maps of a dust index from GMS-5 (dustnpgs at
<http://www.joss.ucar.edu/cgi-bin/joss-catalog/ace-asia/products/index>)

• Maps of absorbing aerosol index from TOMS
([http://toms.gsfc.nasa.gov/aerosols/
aerosols.html](http://toms.gsfc.nasa.gov/aerosols/aerosols.html))

• Maps of aerosol optical depth and Angstrom exponent from SeaWiFS (Hsu
et al. (2002), available at

<http://code916.gsfc.nasa.gov/Missions/ACEASIA/satellite>)

• Maps of optical depths and the dominant aerosol type (dust, black
carbon, sea salt and sulfate) (Higurashi and Nakajima, 2002; Hsu et al.,
2002).

This assessment will also utilize the results of the column closure and
SSA studies (1a and 1b above). These are expected to yield:

• Comparisons between aerosol absorption properties as derived from
radiative flux and as measured by the PSAP instruments aboard the NCAR
C-130 and the CIRPAS Twin-Otter;

• The vertical distribution of aerosol extinction from comparison of
sunphotometer- and in situ- derived aerosol properties (cf. Figures
8-10);

• Information on the vertical distribution of aerosol species based on
the vertical distribution of Angstrom parameters.

This information will be combined with the observed absorption results
to constrain the inputs to the radiative transfer model. For example,
the aerosol observed during the ACE Asia campaign was extremely complex
mixture of dust and urban pollution. Using our detailed radiative
transfer model (Bergstrom et al., 2002b), we will compute the effect of
the multi-modal aerosol on the observed satellite radiances. (The
included multiple scattering code, DISORT, can compute radiances as well
as fluxes.)

To avoid the inconsistency in using one model of aerosol radiative
properties to convert the satellite-measured radiances into aerosol
optical depth and a different model to convert the aerosol optical depth
to aerosol radiative forcing, we also propose to collaborate with the
teams of A. Higurashi (National Institute of Environmental Studies,
Ibaraki, Japan) and T. Nakajima (Univ. of Tokyo, Tokyo, Japan). We will
work with them to develop an aerosol model for SeaWiFS measurements that
will be used in both the conversion of satellite radiances to AOD and in
the conversion of AOD to aerosol radiative forcing of climate. We will
also perform sensitivity tests to assess how changing aerosol model
parameters affects derived forcing, both when using the same model for
both steps, and when using different models in each step. This should
enable us to more accurately estimate the aerosol radiative forcing and
the associated uncertainties. A major objective will be to quantify and
reduce the uncertainties in aerosol radiative-climatic effects cited by
NACIP (Ramanathan et al., 2002)

Initial comparisons between various satellite sensors (e.g., MODIS vs.
SeaWiFS) indicate considerable differences in temporally-averaged fields
of aerosol optical depth. Such differences could be due to the complex
interaction of aerosols and clouds in the western Pacific region and the
associated complications in satellite cloud screening algorithms, or due
to inadequate modeling of the mixtures of various aerosol types in
satellite retrieval algorithms. Hence, as a second element of this task,
we propose to compare the aerosol optical depth fields derived from
various satellite sensors (MODIS, SeaWiFS, MISR, AVHRR) as they are
relevant to the calculation of regional mean aerosol radiative forcing
of climate. Based on the comparison of instantaneously measured aerosol
optical depth between suborbital and satellite sensors, we expect to aid
in explaining any differences found between aerosol products from
different satellite sensors.

[Data Set 2. CLAMS (Summer 2001)]{.underline}. This set includes
measurements on the UW CV-580 by AATS-14 and many in situ sensors, plus
measurements by AERONET and other surface samplers and lidar, all made
in coordination with satellite overpasses. A special journal issue is
planned, with papers due in Spring 2003.

We propose the following research using the CLAMS data set:

(2a) Complete processing and archival of data acquired by AATS-14, using
formats that facilitate intercomparison with aerosol and water vapor
products derived by EOS Terra sensors (e.g., MISR, MODIS, CERES).

(2b) Compare AATS-14 results to ground-based measurements taken by the
MODIS-Atmosphere team using a network of hand-held sunphotometers;
provide AATS-14 measurements during fly-by's at these sites as a
"calibration standard".

(2c) Support the MODIS-Atmosphere team in the development of an AOD
retrieval algorithm over MODIS/MAS sun-glint regions by providing high
spatial resolution AATS-14 measurements.

(2d) Collaborate with the MODIS-Atmospheres team to test the standard
AOD retrieval algorithm in cases of small-scale AOD variability and
gradients; assess small-scale aerosol variability for all low-level
flight legs of the UW CV-580.

(2e) Support the MISR aerosol team in their efforts to improve and
refine the existing MISR AOD look-up tables and retrieval algorithm.

(2f) For AATS-14 data taken during suitable flight patterns, derive
profiles of aerosol extinction spectra and water vapor density by
differentiating optical depth and column water vapor profiles for all
feasible time periods.

(2g) Combine data with in situ measurements to provide tests of closure
and integrated assessments of aerosol and trace gas radiative effects.

(2h) Report results of the analyses in joint publications with
collaborating investigators by the deadline for the JGR-CLAMS special
issue.

[Data Set 3. SAFARI 2000]{.underline}. The first set of SAFARI 2000
journal papers is already in press, including two led by our team
(Schmid et al., 2002a; Bergstrom et al., 2002b) and several others we
coauthored (e.g., Gatebe et al., 2002; Magi et al., 2002; McGill et al.,
2002; Pilewskie et al., 2002). However, the integrated SAFARI 2000 data
set has strong potential for further advanced collaborative analyses,
and this is highly encouraged by the SAFARI organizers. We propose the
following:

(3a) Revisit MODIS validation using MODIS version 4, which uses not only
a new SSA but also allows over brighter surfaces, leading to potentially
more matchups than in Schmid et al. (2002a).

(3b) Redo the MISR comparisons using the latest MISR algorithm (which
has a more complete set of aerosol models).

(3c) Collaborate with Eric Vermote to validate his high-resolution (1km)
over-land MODIS retrieval.

(3d) Compare aerosol SSA values retrieved from satellite with those from
in situ sensors and SSFR on the CV-580.

(3e) Investigate radiative forcing by African outflow aerosols over
stratus clouds off the Namibian coast (which was measured by AATS-14 in
SAFARI-2000 to have AOD in excess of 0.7 in the midvisible).

2.  **Potential Future Experiments and Preferred Aircraft**

Several future experiments relevant to the goals of this proposal are in
various stages of planning or conception. This proposal does not request
funding for [measurements]{.underline} in these experiments. However,
these future experiments are relevant to this proposal for several
reasons. First, the analyses proposed above will support concept
development for such future missions and help prepare the community for
participation. Moreover, if we participate in one or more of these
future experiments with separate funding, the resulting data would help
answer the questions addressed by this proposal. Therefore, we propose
to use some of the requested funds for integrated analyses of such data
sets.

[Experiment 1. Asian Dust Above Monterey (ADAM)]{.underline}. This
experiment, planned for April 2003, will use the CIRPAS Twin Otter to
test predictions by the NAAPS model (Westphal and Liu, 2000; Bucholtz et
al., 2002) of Asian dust outbreaks, cross-Pacific transport, and North
American impacts. We are currently planning to participate in ADAM by
making measurements with AATS-14 using other funding. However, our
available funding cannot cover analyses of our expected ADAM data set.
If this proposal is funded we will analyze our ADAM data set using the
methods exemplified in Section 3 and outlined in Section 4.1.

[Experiment 2. Intercontinental Chemical Transport Experiment-North
America (INTEX-NA).]{.underline} Phase A of this experiment, planned for
May-August 2004, will use the NASA DC-8 and P-3B aircraft to study the
exchange of chemicals and aerosols between continents and the global
troposphere (Singh et al., 2002). INTEX-NA will coordinate its
activities with concurrent measurement programs including satellites (e.
g. Terra, Aura, Envisat), field activities undertaken by the North
American Carbon Program (NACP), and other U. S. and international
partners. INTEX-NA planning documents call for measurements of aerosol
optical depth, and we plan to propose such measurements when the
INTEX-NA call is released. However, funding for such experiments often
does not cover the type of integrated analyses that we typically do in
such integrated experiments. Hence, if we are funded for measurements in
INTEX-NA Phase A, we propose to use funds from this IDS-Radiation
Sciences proposal to perform such integrated analyses. Depending on the
degree of satellite coordination achieved by INTEX-NA, these analyses
could include validation of sensors carried by Terra, Aqua, Aura, and
Envisat (see below).

[Experiment 3. Intercontinental Transport and Chemical Transformation
(ITCT).]{.underline} This experiment is planned to coordinate with
INTEX-NA in Spring-Summer 2004 and make measurements on a NOAA P-3. Its
goals will be similar to those of INTEX-NA, with perhaps more emphasis
on aerosols and their radiative-climatic impact. We have discussed with
NOAA representatives the possibility of flying AATS-6 or AATS-14 on the
NOAA P-3 or perhaps operating an AATS on the NOAA ship Ron Brown.
Depending on funding arrangements with NOAA, there may be a need for
analysis support from the current IDS-Radiation Sciences proposal.

[Experiment 4. African Monsoon Multidisciplinary Analyses
(AMMA).]{.underline} This experiment, planned for 2005, will study the
processes that influence the development of the African Monsoon. An
aerosol component is possible. \[More coming in Prospero email??\]

[Experiment 5. Asian Brown Cloud (ABC) and/or Biomass Aerosol and Smoke
Experiment (BASE-Asia).]{.underline} Several efforts are underway to
plan one or more experiments to study aerosols produced by biomass
burning and other sources in Southeast and East Asia, including Thailand
and possibly China. We will stay in touch with these planning efforts,
and if there is an opportunity to propose participation, we will do so.

**[Note on Satellite Validation]{.underline}**

Many of the above experiments will provide opportunities for validating
both new satellite sensors and those currently flying. Several of
particular note are summarized here.

**OMI on Aura.** The INTEX White Paper (Singh et al., 2002) notes that,
if Aura is making measurements during INTEX, aircraft flights will be
coordinated with Aura overpasses, thus providing opportunities for Aura
validation and integrated studies. Of the Aura sensors, OMI is of
particular relevance to the proposed research, OMI's goals include
measuring aerosols and distinguishing between aerosol types, such as
smoke, dust, and sulfates. As shown in Section 3, AATS measurements as
part of an integrated aircraft payload could make a major contribution
to validating such OMI measurements. We plan to propose such
measurements to the INTEX call when it appears.

**GLAS and CALIPSO.** Both GLAS (scheduled for launch in December 2002
on ICESat) and CALIPSO (August-October 2004 with CloudSat) have a goal
of producing profiles of aerosol extinction from their measurements of
backscattered laser light. As noted in Section 3, we have used AAST-6
and AATS-14 to validate lidar-derived extinction profiles in many
experiments (e.g., Figure 10), including profiles from the
downward-viewing Cloud Physics Lidar System on the ER-2 (Schmid et al.,
2002a). If there is an opportunity to propose validation measurements
for either GLAS or CALIPSO, we plan to do so.

**[Suborbital platform preferences]{.underline}**

The earliest future experiment, ADAM (April 2003) will use the Twin
Otter of the Center for Interdisciplinary Remotely Piloted Aircraft
Studies (CIRPAS). Our 14-channel Ames Airborne Tracking Sunphotometer
(AATS-14) has already flown on the CIRPAS Twin Otter.

(A payload similar to ADAM's, including AATS-14, will fly on the Twin
Otter in the May 2003 Aerosol IOP at the Southern Great Plains site.
Those AATS-14 measurements and analyses are funded separately from this
proposal.)

The next experiments of interest to this proposal are the coordinated
INTEX-NA and ITCT 2K4 (May-August 2004), which will use the NASA DC-8
and P-3B and a NOAA P-3. AATS-6 and -14 have flown on the NASA DC-8 and
on aircraft similar to the P-3 (e.g., CV-580, C-130). We are currently
discussing with NOAA personnel possible ways of integrating AATS-14 on a
NOAA P-3. Recently there has been some mention of the CIRPAS Twin Otter
participating in these experiments, to provide more focus on aerosol
radiative effects than the other platforms will. We would favor this.

The following aircraft can also be well suited to flying an AATS,
depending on configuration and on mission scientific objectives: NSF
HIAPER, NRL P-3, SKYResearch Cessna Caravan.

**4.3 Instrument Maintenance and Enhancement**

As time and funding permit, we propose to explore potential AATS-14
enhancements beyond those implemented in FY02 (see Section 3.7).
Possibilities now being considered include (a) installing a spectrometer
or electrically calibrated pyranometer, and (b) further reducing weight
and size to permit flight opportunities on more platforms and missions.

A separate proposal (Schmid et al., 2002c) proposes to develop and fly
an airborne pointing sun-sky photometer based on AATS-14 and on AERONET
optics and analyses.

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Tanré, D., et al. (w. J.M. Livingston, P.B. Russell), Retrieval of
aerosol optical thickness and size distribution over ocean from the
MODIS Airborne Simulator during TARFOX, *J.* *Geophys. Res., 104*,
2261-2278*,* 1999.

Uno, I*.,* M. Chin, W. Collins, P. Ginoux, P. Rasch, G. R. Carmichael,
and J. J Yienger, ACE-Asia chemical transport modeling overview, *EOS
Trans. AGU*, 82 (47), Fall Meet. Suppl., Abstract A22A-0101, 2001.

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

Wang, J., R. C. Flagan, J. H. Seinfeld, H. H. Jonsson, D. R. Collins, P.
B. Russell, B. Schmid, J. Redemann, J. M. Livingston, S. Gao, D.A. Hegg,
E.J. Welton, and D. Bates, Clear-column radiative closure during
ACE-Asia: Comparison of multiwavelength extinction derived from particle
size and composition with results from sunphotometry *J. Geophys. Res*.,
in press, 2002a.

Wang, J, S. A. Christopher, J. S. Reid, H. B. Maring , D. L. Savoie , B.
N. Holben, J. M. Livingston, P. B. Russell and S-K. Yang, GOES-8
retrieval of dust aerosol optical thickness over the Atlantic Ocean
during PRIDE, *J. Geophys. Res.*, in press, 2002b.

Welton, E. J., Voss, K. J., Gordon, H. R., H. Maring, Smirnov, A.,
Holben, B., Schmid, B., Livingston, J. M., Russell, P. B., et al.,
Ground-based lidar measurements of aerosols during ACE 2: Instrument
description, results, and comparisons with other ground-based and
airborne measurements. *Tellus B 52*, 636-651, 2000.

Welton, E. J., J. R. Campbell, J. D. Spinhirne, and V. S. Scott,
\"Global monitoring of clouds and aerosols using a network of
micro-pulse lidar systems \", in Lidar Remote Sensing for Industry and
Environmental Monitoring, U. N. Singh, T. Itabe, N. Sugimoto, (eds.),
Proc. SPIE, 4153, 151-158, 2001.

Westphal, D. L., and M. Liu, Recent dust events as simulated by NAAPS:
Navy Aerosol Analysis and Prediction System,
<http://irina.colorado.edu/oral/oral_Westphal.htm>, 2000.

Xu, J., M.H. Bergin, R. Greenwald, P.B. Russell, Direct aerosol
radiative forcing in the Yangtze delta region of China: observation and
model estimation, *J. Geophys. Res.*, in press, 2002.

**6 BUDGET**

**7. STAFFING, RESPONSIBILITIES, AND VITAE**

**7.1 Roles of PI and Co-Is**

Dr. Philip Russell will be Principal Investigator. As such, he will
supervise the work, lead the planning, and participate in the analyses,
as well as selected presentations and publications. He will be
responsible for completion of the work within budget and schedule. Drs.
Beat Schmid, Jens Redemann, Robert Bergstrom, and Mr. John Livingston
will be Co-Is, each responsible for key research tasks and for
coordinating with the project team at Ames and with outside
collaborators.

**7.2 Collaborations**

The proposed research requires many comparisons to data produced outside
our group, as well as use of still other data in our integrated
assessments of aerosol effects. The best way to accomplish such research
is through collaborations with the experimenters, analysts, and modelers
who produce these data. This was also true of the previous work on our
IDS and Radiation Sciences tasks. The resulting collaborations are
evidenced by the coauthor lists on the papers cited in Section 2. We
have found that such collaborations develop naturally through
participation in the integrated experiments that we join. Not all these
collaborations can be anticipated in advance. However, several key
collaborations are worth citing here.

**Dr. Peter Pilewskie** of NASA Ames is submitting a separate proposal
to NRA-02-OES-06 that includes collaboration with our team to combine
his SSFR data and our AATS data to derive SSA from the ACE-Asia data
set.

**Dr. Sundar Christopher** of the University of Alabama in Huntsville is
proposing an investigation that would, among other things, use biaxial
scan mode CERES data to develop angular models for estimating radiative
fluxes and thereby reduce uncertainties in aerosol radiative forcing. If
our proposal is funded, we plan to collaborate with Dr. Christopher and
contribute to the validation of such CERES data by furnishing ACE-Asia
AATS-6 and -14 data, and data-use advice.

**7.3. Vitae**

**(a) 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).

**SELECTED PUBLICATIONS (from 103 peer-reviewed papers)**

Russell, P. B., et al., Comparison of aerosol single scattering albedos
derived by diverse techniques in two North Atlantic experiments, *J.
Atmos. Sci.,* *59*, 609-619, 2002.

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

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., 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., 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, 1999.

Russell, P. B., S. Kinne and R. Bergstrom, Aerosol climate effects:
Local radiative forcing and column closure experiments, *J. Geophys.
Res.,* *102*, 9397-9407, 1997.

Russell, P. B., et al. 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., et al. 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., L. Pfister, and H.B. Selkirk, \"The tropical experiment
of the Stratosphere-Troposphere Exchange Project (STEP): Science
objectives, operations, and summary findings, *J. Geophys. Res.*, *98*,
8563-8589, 1993.

Russell, P.B., 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., et al., Satellite and correlative measurements of the
stratospheric aerosol: III. Comparison of measurements by SAM II, SAGE,
dustsondes, filters, impactors, and lidar, *J. Atmos. Sci.*, *41*,
1791-1800, 1984.

**(b) Beat Schmid**

**Abbreviated Curriculum Vitae**

Bay Area Environmental Research Institute

560 Third Street West, Sonoma, CA 95476

## Education

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

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

## Professional Experience

[Bay Area Environmental Research Institute]{.underline}, Sonoma, CA
(1997-Present): Senior Research Scientist

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

[University of Bern]{.underline}, Switzerland (1989-1997): Postdoctoral
Researcher (1995-1997)

## Scientific Contributions

-   9 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),
    SAFARI 2000 (Southern African Regional Science Initiative; 2000),
    and ACE-Asia (Asian Pacific Regional Aerosol Characterization
    Experiment; 2001). Extensive comparison of results (closure studies)
    with other techniques: lidar, optical particle counters,
    nephelometers, and satellites.

-   Participated with the 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.

-   Participated with NASA Ames Cavity Ringdown instrument in Reno
    Aerosol Optics Study (June, 2002).

## Scientific Societies/Editorships

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

-   Member, American Geophysical Union and American Meteorological
    Society

## Selected Publications (from 28 published or in press, plus 1 recently submitted)

Schmid B., et al., Coordinated airborne, spaceborne, and ground-based
measurements of massive, thick aerosol layers during the dry season in
Southern Africa, *J. Geophys. Res.,* accepted, 2002.

Livingston, J. M., et al., incl, B. Schmid, 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.*, submitted, 2002.

Wang, J., et al., incl, B. Schmid, Clear-column radiative closure during
ACE-Asia: Comparison of multiwavelength extinction derived from particle
size and composition with results from sunphotometry J. Geophys. Res.,
submitted, 2002.

Pilewskie, P., et al., incl, B. Schmid, Solar Spectral Radiative Forcing
During the South African Regional Science Initiative, *J. Geophys.
Res.*, submitted, 2002.

Schmid B., et al., Comparison of columnar water-vapor measurements from
solar transmittance methods. *Applied Optics,* Vol. 40, No. 12,
1886-1896, 2001.

Schmid, B., et al., 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., et al., Comparison of Aerosol Optical Depth from Four Solar
Radiometers During the Fall 1997 ARM Intensive Observation Period,
*Geophys. Res. Lett*., *26*(17), 2725-2728, 1999.

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 Geosci. Remote. Sens*., 35(1),
172-182, 1997.

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. *J. Geophys. Res., 101*(D5), 9345-9358, 1996.

Schmid, B., and C. Wehrli, Comparison of Sun Photometer Calibration by
Langley Technique and Standard Lamp. *Appl. Opt.,* *34*(21), 4500-4512,
1995.

**(c) Jens Redemann**

**Abbreviated Curriculum Vitae**

Bay Area Environmental Research Institute, 560 Third Street West,
Sonoma, CA 95476

# PROFESSIONAL EXPERIENCE

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

  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 for the participation of AATS-14 in the CLAMS
    (Chesapeake Lighthouse Aerosol Measurements for Satellites)
    satellite validation study (July 2001). Responsible for proposal
    writing, experiment design and instrument integration. Member of
    CLAMS Science Team.

-   Participated in the SAFARI-2000, ACE-Asia field experiments,
    investigating aerosol-climate interactions.

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

-   Related airborne measurements using sunphotometers, lidar (light
    detection and ranging) systems and flux radiometers to in situ
    measurements of atmospheric (mineral dust) aerosols and gases and
    modeled the local radiative transfer in Earth's atmosphere.

```{=html}
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```
-   Specialized course work in atmospheric sciences, geophysical fluid
    dynamics, cloud physics, radiative transfer and remote sensing.

# HONORS / ORGANIZATIONS

+-----------------------------------------------------------+----------+
| Invited Speaker at the Atmospheric Chemistry Colloquium   | #### J   |
| for Emerging Senior Scientists (ACCESS V)                 | une 1999 |
+-----------------------------------------------------------+----------+
| Outstanding Student Paper Award, American Geophysical     | 1998     |
| Union - fall meeting                                      |          |
+-----------------------------------------------------------+----------+
| NASA Global Change Research Fellowship Awards             | 1        |
|                                                           | 996-1998 |
+-----------------------------------------------------------+----------+
| UCLA Neiburger Award for excellence in the teaching of    | 1997     |
| the atmospheric sciences                                  |          |
+-----------------------------------------------------------+----------+
| American Association for Aerosol Research, American       | since    |
| Geophysical Union                                         | 1997     |
+-----------------------------------------------------------+----------+

# SUMMARY OF BIBLIOGRAPHY (selection is appended)

8 peer-reviewed (6 senior-authored + 2 junior-authored), + 4 submitted
junior-authored journal articles. 21 senior-authored (33 total)
conference presentations.

# BIBLIOGRAPHY (Selection) 

Russell, P.B., J. Redemann, et al., Comparison of aerosol single
scattering albedos derived by diverse techniques in two North Atlantic
experiments, *J. Atmos. Sci.,* *59*, 609-619, 2002.

Redemann, J., P.B. Russell, and P. Hamill, Dependence of aerosol light
absorption and single scattering albedo on ambient relative humidity for
sulfate aerosols with black carbon cores, *J. Geophys. Res.*, *106*,
27,485-27,495, 2001.

Redemann, J., et al., 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, *J. Geophys. Res.* ,
*105*, 9949-9970, 2000.

Redemann, J., et al., Case studies of the vertical structure of the
direct shortwave aerosol radiative forcing during TARFOX, *J. Geophys.
Res., 105,* 9971-9979, 2000.

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., 103,* 23,287 - 23,298, 1998.

# (d) John M. Livingston

SRI International

MS 306-42

333 Ravenswood Avenue

Menlo Park, CA 94025

# Education

  ---------------------------- --------- ----------------------------------
  Notre Dame Year-in-Japan     1971-72   Sophia University, Tokyo, Japan
  Program                                

  B.S., earth sciences         1974      University of Notre Dame, Notre
                                         Dame, IN

  M.S., atmospheric sciences   1977      University of Arizona, Tucson, AZ

  M.B.A.                       1992      Santa Clara University, Santa
                                         Clara, CA
  ---------------------------- --------- ----------------------------------

# Professional Experience

[SRI International]{.underline} (formerly Stanford Research Institute),
Menlo Park, CA (1978-present)

\- Senior Research Meteorologist, Applied Physical Sciences Laboratory

[University of Arizona]{.underline},Tucson, AZ (1974-1977)

\- Research assistant, Institute of Atmospheric Physics

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

# Scientific Contributions

\- Acquisition and analysis of ground-based, airborne, and shipboard
sunphotometer measurements in a variety of coordinated international
field campaigns to study the radiative impact on climate of
anthropogenic pollution, volcanic aerosol, and African and Asian dust

\- Validation of satellite aerosol 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

\- Analysis of ground-based lidar measurements obtained at Sondrestrom,
Greenland to retrieve atmospheric density and temperature profiles in
the polar stratosphere and mesosphere and to characterize the physical
properties of noctilucent clouds

\- 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

\- Error analysis and simulation of lidar aerosol measurements

\- Analysis of lidar propagation through fog, smoke, and dust clouds

\- Weather forecasting for large-scale air pollution field study

\- Testing and evaluation of an offshore coastal dispersion computer
model

\- Application of objective wind field/trajectory models to
meteorological measurements

# Honors and Awards

\- 1997 NASA Ames Research Center Contractor of the Year

## Scientific Societies 

\- American Geophysical Union

### Publications 

Over 45 scientific publications in various major atmospheric science
journals

Selected publications:

Livingston, J. M., P. B. Russell, J. S. Reid, J. Redemann, B. Schmid, D.
Allen, O. Torres, R. C. Levy, L. A. Remer, B. N. Holben, A. Smirnov, O.
Dubovik, E. J. Welton, J. Campbell, S. A. Christopher, J. Wang, 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.*, submitted,
2002.

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. Gasso, D. Hegg, D.R. Collins, R.C. Flagan, J.H. Seinfeld, V.
Vitale, and C. Tomasi, 2000: "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*, [52B]{.underline}*.*

Livingston, J.M., and P.B. Russell, 1989: "Retrieval of Aerosol Size
Distribution Moments from Multiwavelength Particulate Extinction
Measurements," *J. Geophys. Res.*, [94]{.underline}, 8425-8433.

Livingston, J.M., and R.M. Endlich, 1988: "The Relationship of
Satellite-Inferred Stratospheric Aerosol Extinction to the Position of
the 50 mb North Polar Jet Stream," *J. Appl. Meteor.*, [27]{.underline},
757-773.

Livingston, J.M., and E.P. Krider, 1978: "Electric Fields Produced by
Florida Thunderstorms," *J. Atmos. Sci.*, [83]{.underline}, 385-401.

Ludwig, F.L., J.M. Livingston, and R.M. Endlich, 1991: "Use of Mass
Conservation and Critical Dividing Streamline Concepts for Efficient
Objective Analysis of Winds in Complex Terrain," *J. Appl. Meteor.*,
[30]{.underline}, 1490-1499.

Oberbeck, V.R., J.M. Livingston, P.B. Russell, R.F. Pueschel, J.N.
Rosen, M.T. Osborn, M.A. Kritz, K.G. Snetsinger, and G.V. Ferry, 1989:
"SAGE II Aerosol Validation: Selected Alti­tude Measurements, Including
Particle Micromeasurements," *J. Geophys. Res.*, [94]{.underline},
8467-8380.

Pueschel, R.F., and J.M. Livingston, 1990: "Aerosol Spectral Optical
Depths: Jet Fuel and Forest Fire Smokes," *J. Geophys. Res.*,
[95]{.underline}, 22,417-22,422.

> Russell, P.B., J.M. Livingston, P. Hignett, S. Kinne, J. Wong, A.
> Chien, R. Bergstrom, P. Durkee, and P.V. Hobbs, 1999: "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]{.underline}, 2289-2307.

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, 1993: "Post-Pinatubo Optical Depth Spectra vs.
Latitude and Vortex Structure: Airborne Tracking Sunphotometer
Measurements in AASE II," *Geophys. Res. Lett.*, [20]{.underline},
2571-2574.

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

Uthe, E.E., J.M. Livingston, and N.B. Nielsen, 1992: "Airborne Lidar
Mapping of Ozone Concen­trations During the Lake Michigan Ozone Study,"
*J. Air and Waste Management Assoc.*, [42]{.underline}, 1313-1318.

Uthe, E.E., and J.M. Livingston, 1986: "Lidar Extinction Methods Applied
to Observations of Obscurant Events," *Appl. Opt.*, [25]{.underline},
678-684.

**(e) Robert W. Bergstrom**

### Abbreviated Currriculum Vitae

Bay Area Environmental Research Institute

560 Third Street West, Sonoma, CA 95476

**Education:**

B.S., Mechanical Engineering, Oregon State University (1968).

M.S. and Ph.D., Mechanical Engineering, Purdue University (1969 and
1972).

J.D., Law, Stanford University (1983). Member of the California Bar
(1983-present).

**Professional Experience:**

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

Founder of the Bay Area Environmental Research Institute, San Francisco,
CA (1992). Currently, Director of Research. Principal Investigator on
several Cooperative Agreements with NASA Ames Research Center.

# Selected Recent Publications

Bergstrom, R.W., P. Pilewskie, B. Schmid, P.B. Russell, Comparision of
measured and predicted aerosol radiative effects during SAFARI 2000,
accepted, *J. Geophys. Res.,* 2002.

Bergstrom, R. W., P. B. Russell, and P. Hignett, Wavelength dependence
of the absorption of black carbon particles: Predictions and results
from the TARFOX experiment and implications for the aerosol single
scattering albedo, *J. Atmos. Sci., 59,* 568-578, 2002.

Pilewskie, P. et al. (including R.W. Bergstrom), The Discrepancy between
measured and modeled downwelling solar irradiance at the ground:
Dependence on water vapor. *Geophys. Res. Lett., 25*, 137-14, 2000.

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

Sokolik, I., O.B. Toon and R.W. Bergstrom, Modeling the radiative
characteristics of airborne mineral aerosols at infrared wavelengths,
*J. Geophys. Res., 103*, 8813-8826, 1998.

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

Russell, P.B. S. Kinne and R.W. Bergstrom: Aerosol climate effects:
Local radiative forcing and column closure experiments, *J. Geophys.Res,
102*, 9397, 1997.

**8. CURRENT AND PENDING SUPPORT FOR PRINCIPAL INVESTIGATOR**

  ------------------------- --------------------- ------------------------
  **Short Title**           **Agency/Task No.**   **Duration**

  Satellite-Sunphotometer   NASA RTOP             2/2000-12/2002
  Studies of Aerosol,...    291-01-91-45          

  Global Aerosol            NASA RTOP             10/1998-3/2003
  Climatology (GACP) &      622-44-75-10          
  Bridge Period                                   

  Airborne Sunphotometry in NASA RTOP             8/2002-7/2003
  SOLVE II                  621-45-51-10          

  ACE-2 & ACE-Asia Aerosol  NOAA Interagency      5/2000-4/2003 (Renewal
  Radiative Effect Studies  Transfer of Funds     proposed)
                            NA02AANRG0129         

  Composite Data Analyses   NASA RTOP             10/1995-9/2002 (Renewal
  for Pinatubo Volcanic     621-45-51-10          proposed)
  Aerosols for SAGE II                            

  SAGE III Science Team     NASA RTOP             11/1990-9/2002 (Renewal
                            229-10-32-00          proposed)
  ------------------------- --------------------- ------------------------