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Aerosol Optical Thickness

Other Names

Aerosol Optical Depth, τ, tau


"Aerosol Optical Thickness" is the degree to which aerosols prevent the transmission of light.
The aerosol optical depth or optical thickness (τ) is defined as the integrated extinction coefficient over a vertical column of unit cross section. Extinction coefficient is the fractional depletion of radiance per unit path length (also called attenuation especially in reference to radar frequencies). The optical thickness along the vertical direction is also called normal optical thickness (compared to optical thickness along slant path length).


(1) Atmospheric correction of remotely sensed surface features (5) Air Quality
(2) Monitoring of sources and sinks of aerosols (6) Health and Environment
(3) Monitoring of volcanic eruptions and forest fire (7) Earth Radiation Budget
(4) Radiative Transfer Model (8) Climate Change

GES DISC Datasets

Quick Search for 'Aerosol Optical Thickness' with Mirador
Click on the corresponding 'WHOM access' links in the table below to access products containing specific parameter.

Parameter Units Platform /Instrument Data
Begin Date End Date WHOM Access Doc
Aerosol Optical Thickness at ground pixel resolution None Aura/OMI 2004-08-15 Current OMAERUV.002 Y
Aerosol Optical Thickness at ground pixel resolution globally gridded (0.25 deg lat/lon grid) None Aura/OMI 2004-08-15 Current OMAERUVG Y
Aerosol Optical Thickness at 0.38 µm over land and ocean globally gridded (~1 x 1.25 deg grids) None Earth Probe/TOMS 1996-07-25 2005-12-31 TOMSEPL3 Y
Meteor-3/TOMS 1991-08-22 1994-12-27 TOMSM3L3 Y
Nimbus-7/TOMS 1978-11-01 1993-05-06 TOMSN7L3 Y

Other sources for data

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  • Last updated: November 16, 2007 17:43:37 GMT