Open AccessDesert dust aerosol columnar properties over ocean and continental Africa from Lidar in‐Space Technology Experiment (LITE) and Meteosat synergy
Author(s) -
Berthier S.,
Chazette P.,
Couvert P.,
Pelon J.,
Dulac F.,
Thieuleux F.,
Moulin C.,
Pain T.
Publication year - 2006
Publication title -
journal of geophysical research: atmospheres
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.67
H-Index - 298
eISSN - 2156-2202
pISSN - 0148-0227
DOI - 10.1029/2005jd006999
Subject(s) - aerosol , lidar , environmental science , remote sensing , mineral dust , aeronet , atmospheric sciences , radiative forcing , angstrom exponent , earth's energy budget , meteorology , geology , radiation , geography , physics , optics
The new generation of spaceborne backscatter lidar systems, prefigured by the Lidar in‐Space Technology Experiment (LITE) mission in September 1994, will give new insight on the vertical distribution of both aerosols and clouds in the atmosphere. This is especially of importance for aerosols over land, where retrievals from passive sensors are known to be more difficult because of the surface contribution. Here we analyze mineral dust aerosol transport events through a new approach coupling the active LITE and passive Meteosat‐5 spaceborne observations. The Meteosat‐derived aerosol optical thickness at 550 nm is shown to be a good boundary condition for the lidar inversion in order to retrieve both the aerosol backscatter to extinction ratio (BER) and the aerosol extinction vertical profile above the Tropical Atlantic Ocean (TAO) and the Mediterranean Sea. Sensitivity tests indicate that the aerosol scattering coefficient is retrieved within a 20% relative uncertainty. Air mass trajectories allow us to further retrieve the vertical profile of aerosol optical properties over the continent in the Saharan Heat Low (SHL) region using the BER determined over the ocean. Results confirm a large dispersion of the BER which is not attributed to errors in the method. This shows the need to account for such dispersion in the retrieval of dust aerosol optical thickness and aerosol impact on the earth radiative budget. The coupling between LITE and Meteosat‐5 made here is shown to be interesting for an improvement of the direct dust aerosol forcing, and results should be improved by the CALIOP‐MODIS synergy.