# Presentation: 222546

## Looking Forward:

- Using MODIS for aerosol
- science over the next 3 years

- Lorraine A. Remer, J. Vanderlei Martins,
- Robert Levy, Shana Mattoo, Charles Ichoku,
- Richard Kleidman, Hongbin Yu, Ilan Koren

## Where do we go from here?

- The MODIS aerosol algorithm
-  Aerosol-cloud interaction
-  Absorption and composition
-  Air quality and long range transport of aerosols
-  Lidar

## The MODIS Algorithm: Accomplishments

- Recent improvements to the over ocean retrieval

## The MODIS Algorithm: Accomplishments

- Recent improvements to the over land algorithm.

- Levy et al. (2006)

## The MODIS Algorithm: For the future

- Develop an urban product: surface

- Robert Levy’s work (ATBD)

- Urban: y = 0 +0.77x

- nonUrban: y=0.007 + 0.51x

## The MODIS Algorithm: For the future

- Develop an
- urban product:
- Fine resolution

- Work from Shana Mattoo
- Data from Andrea Castanho

## The MODIS Algorithm: For the future

- POLDER

- Use POLDER with MODIS to solve
- the nonsphericity issues once and
- for all.

- Herman et al. (2005)

## The MODIS Algorithm: For the future

- reflectance

- Distance from clouds (km)

- Work by
- Ilan Koren

- MODIS image

- Distance from clouds

## The MODIS Algorithm: For the future

- Develop an urban product: surface reflectance
-     assumptions and finer resolution.
- Combine MODIS and POLDER to solve
-     nonspherical problems.
- Elevated reflectance in the vicinity of clouds:
-     real or artifact?  Deal with it.

## Cloud-Aerosol Interaction

- In this elevation of reflectance near clouds, is any of it real?

- We don’t think it is classical
- cloud contamination.

- Work by A. Marshak

## Cloud-Aerosol Interaction

- Wen et al. (2006; in preparation)

- What about enhancement of radiation from scattering light
- from cloud sides into the satellite view?

- That is a possible artifact.

## Cloud-Aerosol Interaction

- However, it could also be real
- Hygroscopic growth to larger, more optically effective sizes
- Cloud outflow and decay

- Remer et al. (1997)
- From work by
- Santiago Gassó

## Cloud-Aerosol Interaction

- The more
- absorbing the aerosol
- the more likely
- it will act to increase
- cloud cover
- Kaufman and Koren
- Science (2006)

## Cloud-Aerosol Interaction

- We think that the aerosol absorption is the key to
- understanding the aerosol role in modifying cloud cover.
- We will approach this problem with a measurement-based
- strategy using a variety of instruments, but supported by
- modeling.
- The end, as always, is a better estimate of the aerosols’
- roles in influencing climate change and the hydrological
- cycle.

## Aerosol absorption and composition

- Work by J. Vanderlei Martins

- fine

- coarse

- From Sede Boker, Israel

- Both size and absorption characteristics matter
- in determining composition.

## Aerosol absorption and composition

- More work by
- J. Vanderlei Martins

- Note that in the UV, there is a deviation from the -1 curve
- that characterizes “black carbon”
- Kirchstetter et al. (2004) shows similar plots.  The deviation is due to different combustion efficiencies.

## Aerosol absorption and composition

- wavelength

- 

- 

- fmf

- base

- The UV is sensitive to absorption.  The midIR to size.

- Work by
- Viktor Zubko

- We will combine OMI and MODIS to cover this range.

## Aerosol absorption and composition

- Work by
- J. Vanderlei Martins

- There is a one-to-one
- Relationship between
- Rcrit and o.

## Aerosol absorption and composition

- You need a variety
- of surface reflectances
- so you need to
- work over land.
- You need two images,
- one with aerosol,
- one without, having
- the same geometry.

## Aerosol absorption and composition

- Critical Reflectance

- Path Radiance

- Martins

## Aerosol absorption: Laboratory work

## Air Quality and long range transport

- Kaufman et al. (2005)

- Long range transport of dust.

## Air Quality and long range transport

- It doesn’t have to be dust and it doesn’t have to be the Atlantic
- Hongbin Yu has been working in this area.
- Other aspects of air quality:
- Producing an urban aerosol product from MODIS
- Using results of INTEX-B to refine assumptions in retrievals.

## Fire radiative energy

## Looking Forward:

- We still have things to do with the MODIS algorithm
-      (urban product, nonsphericity, cloud artifacts)
- Some cloud “artifacts” may be real and that would
-       be exciting.
- Aerosol absorption may be key to understanding
-       aerosol influences on cloud cover.
- 4. We have 3 plans for increasing our knowledge on
-     absorption (MODIS-OMI; critical reflectance;
-     laboratory analysis).
- 5. Fire emissions
- 6. MODIS and CALIPSO joint inversions.

## The MODIS aerosol group (more or less) Sept 2006

- Announcing the arrivals of:
- Claire Yu, Jordan Levy, Arava Koren