The Global Aerosol Climatology Project (GACP), established in 1998 as part of the NASA Radiation Sciences Program and the Global Energy and Water Cycle Experiment (GEWEX), provides a 23-year global aerosol climatology compiled from channel-1 and -2 AVHRR data and supplemented by data from other satellites, field observations, and chemical-transport modelling.

Example result / latest result (if near-real time)


Satellite: TIROS / NOAA
Instrument(s): AVHRR
Instrument/algorithm PI: Michael Mishchenko, NASA GISS
Contact details: mmishchenko[at]
Parameter(s): AOD, Ångström exponent
Aerosol algorithm: GACP
Cloud screening: ISCCP
Aerosol model: spherical aerosols, wavelength independent index of refraction, monomodal size distribution
Retrieval assumptions: globally identical aerosol characterization
Retrieval limitations: ocean only
Spatial, temporal coverage: 1981-2006 / climatological, global oceans
Spatial, temporal resolution: 1°x1° daily
Operations status: reprocessing
Validation status: statistical comparisons with ship-borne sunphotometer data over the period 1983-2001
Quality control: ISCCP
last algorithm version: N/A
last validation: March 2007





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