# Presentation: 662441

## The Role of Aerosols in Cloud Growth, Suppression, and Precipitation:Yoram Kaufman and his Contributions

- The Role of Aerosols in Cloud Growth, Suppression, and Precipitation:Yoram Kaufman and his Contributions

- Aerosol optical & microphysical properties
- Ground-based sunphotometer measurements
- Optical thickness
- Size distribution & absorption properties
- Aircraft remote sensing
- SCAR-B and field validation/prototyping
- Satellite remote sensing
- Dense dark vegetation
- Spectral surface albedo characterization
- MODIS aerosol over land
- Cloud-aerosol interaction
- Relationship between absorbing and nonabsorbing aerosol & cloud formation, cloud cover, and optical properties

- Michael D. King
- NASA Goddard Space Flight Center

## Surface Measurements of Sun/Sky Radiation (B. N. Holben, T. F. Eck, I. Slutsker et al. – NASA GSFC)

- AERONET
- Automatic recording and transmitting sun/sky photometers
- Data Base: Aerosol optical thickness, size distribution, phase function, optical properties, and precipitable water
- Collaborative:	NASA – instruments/sites and centralized calibration & database
- 		Non-NASA – instruments/sites

- Holben et al. (1998)

- 589 citations

## AERONET-An Internationally Federated Network (B. N. Holben, T. F. Eck, O. Dubovik, A. Smirnov et al. – NASA GSFC)

- AERONET-An Internationally Federated Network (B. N. Holben, T. F. Eck, O. Dubovik, A. Smirnov et al. – NASA GSFC)

- Characterization of aerosol optical properties
- Validation of satellite aerosol retrievals and model predictions
- Near real-time acquisition; long term measurements
- aeronet.gsfc.nasa.gov

- 589 citations

## Aerosol Climatology from AERONET(O. Dubovik, B. N. Holben, T. F. Eck, A. Smirnov et al. - GSFC)

- Dubovik et al. (2002)

- Aerosol Climatology from AERONET(O. Dubovik, B. N. Holben, T. F. Eck, A. Smirnov et al. - GSFC)

- Cooling

- Heating

- Hansen et al. (1997)

## Difference between the Reflection Function and Surface Reflectance as a function of Ag and 0(Y. J. Kaufman and R. S. Fraser – NASA GSFC)

- Difference between the Reflection Function and Surface Reflectance as a function of Ag and 0(Y. J. Kaufman and R. S. Fraser – NASA GSFC)

- Fraser and Kaufman (1985)

- 83 citations

- Retrieval of a
- Optical thickness increases with a for dark surfaces
- Optical thickness decreases with a for bright surfaces
- There is a critical Ag where reflection function is insensitive to a
- depends on single scattering albedo

## Aerosol Effects on Reflected Radiation over Land (M. D. King, Y. J. Kaufman, D. Tanré, T. Nakajima – GSFC, Lille, Tokyo)

- Aerosol Effects on Reflected Radiation over Land (M. D. King, Y. J. Kaufman, D. Tanré, T. Nakajima – GSFC, Lille, Tokyo)

- Biomass burning
- Cuiabá, Brazil (August 25, 1995)

- 20 km

- 12  km

- R  = 0.66 μm
- G  = 0.55 μm
- B  = 0.47 μm

- R  = 1.6 μm
- G  = 1.2 μm
- B  = 2.1 μm

- King et al. (1999)

- 155 citations

- Ag (2.1 μm) < 0.10
- 0.10 < Ag (2.1 μm) < 0.15

- 0 = 36°

## Surface Reflectance at Near-Infrared Wavelengths (Y. J. Kaufman, A. Wald,  L. A. Remer et al. – NASA GSFC, U. Lille)

- Surface reflectance is high at 2.2 μm, moderate at 0.66 μm, and low at 0.49 μm
- The aerosol effect on reflected solar radiation is small at 2.2 μm and large at 0.49 μm
- MODIS operational algorithm over land assumes

- Surface Reflectance at Near-Infrared Wavelengths (Y. J. Kaufman, A. Wald,  L. A. Remer et al. – NASA GSFC, U. Lille)

- Ag(0.47 μm) 	= 0.5Ag(0.66 μm)
- 	= 0.25Ag(2.1 μm)

- Kaufman et al. (1997)

- 82 citations

**Notes:**
Kaufman, Y. J., A. Wald, L. A. Remer, B. C. Gao, R. R. Li, and L. Flynn, 1997b: Remote sensing of aerosol over the continents with the aid of a 2.2 μm channel. IEEE Trans. Geosci. Remote Sens., 36, 1286–1298.

## Dynamic Aerosol Models (L. A. Remer, Y. J. Kaufman and B. N. Holben – NASA GSFC)

- Accumulation mode particles (*r* < 0.3 μm)
- mostly organic smoke particles or sulfates
- depend on optical thickness
- Aerosol-free troposphere plus stratospheric aerosol (0.3 μm < *r* < 0.8 μm)
- Maritime salt particles in the mid-Atlantic region (0.8 μm < *r* < 2.5 μm)
- Coarse particles (*r* > 2.5 μm)

- King et al. (1999)

- 155 citations

## Remote Sensing of Aerosol over Land: SCAR-B (D. A. Chu, Y. J. Kaufman, L. A. Remer, B. N. Holben – NASA GSFC)

- Chu et al. (1998)

- Remote Sensing of Aerosol over Land: SCAR-B (D. A. Chu, Y. J. Kaufman, L. A. Remer, B. N. Holben – NASA GSFC)

- Spectral optical thickness derived from MAS
- Intercomparison with ground-based AERONET
- Dot-dashed lines are the retrieval error (a = 0.05 ± 0.2a) anticipated using the MODIS aerosol optical thickness retrieval algorithm

- 24 citations

- Brazil (August-September 1995)

**Notes:**
Chu, D. A., Y. J. Kaufman, L. A. Remer, and B. N. Holben, 1998: Remote sensing of smoke from MODIS airborne simulator during the SCAR-B experiment.  J. Geophys. Res., 103, 31979–31988.

## Spectral Variability of Urban Ecosystem(E. G. Moody, M. D. King, C. B. Schaaf, S. Platnick - GSFC, Boston U.)

- Moody et al. (2005)

- January - June

## Remote Sensing of Aerosol over Ocean: TARFOX (D. Tanré, L. A. Remer, Y. J. Kaufman et al. – U. Lille, NASA GSFC)

- Remote Sensing of Aerosol over Ocean: TARFOX (D. Tanré, L. A. Remer, Y. J. Kaufman et al. – U. Lille, NASA GSFC)

- Spectral optical thickness derived from MAS using the MODIS at-launch algorithm
- Aerosol optical thickness measured by the sunphotometer (AATS-6) aboard the University of Washington C-131A aircraft

- 38 citations

- Atlantic Ocean (July 1996)

## Validation of Aerosol Retrievals over Ocean: TARFOX (D. Tanré, L. A. Remer, Y. J. Kaufman et al. – U. Lille, NASA GSFC)

- Retrieval of a
- Spectral optical thickness derived from MAS using MODIS at-launch algorithm
- Aerosol optical thickness measured by the sunphotometer (AATS-6) aboard the University of Washington C-131A aircraft

- King et al. (1999)

- 155 citations

- Tanré et al. (1999)

- 38 citations

## How well does Terra Represent the Daily Average? (Y. J. Kaufman, B. N. Holben, D. Tanré et al. - NASA GSFC, Univ. Lille)

- Kaufman et al. (2000)

- 32 citations

- AERONET analysis of a
- Scatter plot of the daily ratio of a during Terra overpass time to the daily average
- no systematic bias
- No diurnal bias observed in Ångström exponent or column water vapor

- 0.01

- 1

- 0.1

- 10

- 0.001

- 1.5

- 0.5

- 1.0

- 0.5

- Ratio of parameter for Terra/whole day

- Terra aerosol optical thickness (550 nm)

- 1.0

- 0.5

- 1.0

- 0.0

- 0.5

- 1.0

- 1.5

**Notes:**
Rayleigh Scattering calculations - comparison with Coulson, Dave, and Sekera (Auxiliary Equation) Tables.

## MODIS Aerosol Product(Y. J. Kaufman, L. A. Remer, D. Tanré - NASA GSFC, Univ. Lille)

- Seven MODIS bands are utilized to derive aerosol properties
- 0.47, 0.55, 0.65, 0.86, 1.24, 1.64, and 2.13 μm
- Ocean
- reflectance contrast between cloud-free atmosphere and ocean reflectance (dark)
- aerosol optical thickness (0.55-2.13 μm)
- size distribution characteristics (fraction of aerosol optical thickness in the fine particle mode; effective radius)
- Land
- dense dark vegetation and semi-arid regions determined where aerosol is most transparent (2.13 μm)
- contrast between Earth-atmosphere reflectance and that for dense dark vegetation surface (0.47 and 0.66 μm)
- aerosol optical thickness (0.47 and 0.66 μm)
- fraction of aerosol optical thickness in the fine particle mode

- Kaufman et al. (1997)

- 179 citations

- Tanré et al. (1997)

- 190 citations

**Notes:**
Rayleigh Scattering calculations - comparison with Coulson, Dave, and Sekera (Auxiliary Equation) Tables.

## Terra/MODIS Aerosol Optical Thickness  (Y. J. Kaufman, L. A. Remer, D. Tanré - NASA GSFC, Univ. Lille)

- Terra/MODIS Aerosol Optical Thickness  (Y. J. Kaufman, L. A. Remer, D. Tanré - NASA GSFC, Univ. Lille)

- True Color Composite (0.65, 0.56, 0.47)

- May 4, 2001

- Aerosol Optical Thickness

- 0.4

- 0.8

- 0.0

- 0.2

- 0.6

- 1.0

- a (0.56 μm)

- sunglint

- 97 citations

**Notes:**
Recently came up with a way to visualize both the retrievals and the cloud phase simultaneously with a single image.

## MODIS Monthly Mean Aerosol Optical Thickness(Y. J. Kaufman, D. Tanré, O. Boucher – NASA GSFC, U. Lille)

- Terra
- September 2000

- Fine Mode
- Industrial pollution
- US, Europe, China, India
- Smoke from biomass burning
- South America (Brazil, Bolivia)
- Southern Africa (Angola, Zambia)
- Australia, Borneo
- Coarse Mode
- Desert dust
- Sahara, Arabian Sea
- Sea salt
- Southern ocean

- Kaufman et al. (2002)

- 195 citations

## Terra/MODIS Global Aerosol Optical Properties (Y. J. Kaufman, L. A. Remer, and D. Tanré – NASA GSFC, U. Lille)

- Aerosol Optical Thickness

- August 30, 2001

- Fine Mode vs Coarse Mode Aerosol

- 90

- -90

- Latitude

- 0

- -45

- 45

- Longitude

- 0

- 1.0

- 0.0

- 0.0

- 0.25

- 0.5

- Aerosol Optical Thickness

- Fine Aerosol Fraction

## Monthly Mean Aerosol Optical Properties(L. A. Remer, Y. J. Kaufman, and D. Tanré et al. – GSFC, U. Lille)

- Monthly Mean Aerosol Optical Properties(L. A. Remer, Y. J. Kaufman, and D. Tanré et al. – GSFC, U. Lille)

- April 2005 (Collection 5)
- Aqua

## Zonal Mean Aerosol Optical Thickness(L. A. Remer, Y. J. Kaufman, and D. Tanré et al. – GSFC, U. Lille)

- Zonal Mean Aerosol Optical Thickness(L. A. Remer, Y. J. Kaufman, and D. Tanré et al. – GSFC, U. Lille)

- April 2005 (Collection 5 vs Collection 4)

- Aqua

**Notes:**
QA-weighted & Pixel Count Weighting

## Zonal Mean Aerosol Fine Mode Fraction(L. A. Remer, Y. J. Kaufman, and D. Tanré et al. – GSFC, U. Lille)

- Zonal Mean Aerosol Fine Mode Fraction(L. A. Remer, Y. J. Kaufman, and D. Tanré et al. – GSFC, U. Lille)

- April 2005 (Collection 5)

- Aqua

**Notes:**
QA-weighted & Pixel Count Weighting

## Effect of Smoke and Dust on Shallow Clouds (Y. J. Kaufman, I. Koren, L. A. Remer, D. Rosenfeld, Y. Rudich –GSFC, Hebrew U., Weizmann Inst.)

- Aerosols

- Kaufman et al. (2005)

- 22 citations

- dust

- smoke

- pollution

- sea salt

- stratiform

- mixed

- convective

- Dust and sea salt
- a(fine mode)/a(total) < 0.50

- Pollution and smoke
- a(fine mode)/a(total) > 0.50

- Clouds

- Deep convective clouds
- pc < 300 hPa

- Mixed
- 640 hPa < pc < 300 hPa

- Low-level stratiform clouds
- pc > 640 hPa

## Effect of Smoke and Dust on Shallow Clouds (Y. J. Kaufman, I. Koren, L. A. Remer, D. Rosenfeld, Y. Rudich –GSFC, Hebrew U., Weizmann Inst.)

- June - August 2002

- Kaufman et al. (2005)

- Aerosol indirect effects
- Increase in stratiform cloud cover with an increase in aerosol concentration
- Lower concentration of aerosols associated with larger effective radius
- Assessed the impact of meteorology and how it varies as opposed to aerosol properties
- The aerosol forcing corresponding to the increase in cloud cover is ~ 6 W/m2 in the June-Aug period over the Atlantic Ocean

- 22 citations

- 5°-30°N

- 20°S-5°N

- 5°-30°N

- 20°S-5°N

**Notes:**
Recently came up with a way to visualize both the retrievals and the cloud phase simultaneously with a single image.

## Publications on ‘MODIS’ AND ‘Aerosol’ (Y. J. Kaufman – NASA GSFC)

- Publications on ‘MODIS’ AND ‘Aerosol’ (Y. J. Kaufman – NASA GSFC)

- Year

- Publications on ‘MODIS’ AND ‘Aerosol’

**Notes:**
Recently came up with a way to visualize both the retrievals and the cloud phase simultaneously with a single image.

## Aerosol properties & their impact on climate pioneered by Yoram Kaufman
Atmospheric correction and calibration of satellite sensors
Dense dark vegetation and retrievals of aerosol optical properties over land 
Visionary in establishing a multiyear spectral aerosol climatology, later supplanted by worldwide AERONET ground-based sun/sky radiometers
Aerosol effect on negating influence of CO2 increases in Earth’s atmosphere
Satellite algorithms for aerosol optical thickness and fine mode fraction
Effects of aerosols on cloud suppression, optical properties, and precipitation
Key publications that have had a long and influential role in aerosol science
Holben, B. N. et al., 1998: AERONET—A federated network.  Remote Sens. Environ., 66, 1-16. [591 citations]
King, M. D., Y. J. Kaufman, W. P. Menzel, and D. Tanré, 1992: Remote sensing of cloud, aerosol, and water vapor properties from MODIS. IEEE Trans. Geosci. Remote Sens., 30, 2-27. [245 citations]
Kaufman, Y. J., D. Tanré, and O. Boucher, 1978: A satellite view of aerosols in the climate system.  Nature, 419, 16971-16988. [192 citations]
Published over 200 papers with over 7500 citations
412 different co-authors

- Atmospheric correction and calibration of satellite sensors
- Dense dark vegetation and retrievals of aerosol optical properties over land
- Visionary in establishing a multiyear spectral aerosol climatology, later supplanted by worldwide AERONET ground-based sun/sky radiometers
- Aerosol effect on negating influence of CO2 increases in Earth’s atmosphere
- Satellite algorithms for aerosol optical thickness and fine mode fraction
- Effects of aerosols on cloud suppression, optical properties, and precipitation
- Key publications that have had a long and influential role in aerosol science
- Holben, B. N. et al., 1998: AERONET—A federated network.  *Remote Sens. Environ*., **66**, 1-16. [591 citations]
- King, M. D., Y. J. Kaufman, W. P. Menzel, and D. Tanré, 1992: Remote sensing of cloud, aerosol, and water vapor properties from MODIS. *IEEE Trans. Geosci. Remote Sens*., **30**, 2-27. [245 citations]
- Kaufman, Y. J., D. Tanré, and O. Boucher, 1978: A satellite view of aerosols in the climate system.  *Nature*, **419**, 16971-16988. [192 citations]
- Published over 200 papers with over 7500 citations
- 412 different co-authors

- Summary and Conclusions

## Dr. Yoram J. KaufmanRadiative transfer, aerosol remote sensing, aerosol-cloud interactions, colleague and friend 

- Dr. Yoram J. KaufmanRadiative transfer, aerosol remote sensing, aerosol-cloud interactions, colleague and friend