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Kaufman, Y. J., I. Koren, L. A. Remer, D. Tanre, P. Ginaux, and S. Fan, 2004: Dust transport and deposition observed from the Terra-MODIS space observations. J. Geophys. Res..
Meteorological observations, in situ data and satellite images of dust episodes were used already in the 1970s to estimate that 100 Tg of dust are transported from Africa over the Atlantic Ocean every year between June and August and deposited in the Atlantic Ocean and the Americas. Desert dust is a main source of nutrients to oceanic biota and the Amazon forest, but deteriorates air quality as shown for Florida. Dust affects the Earth
radiation budget, thus participating in climate change and feedback mechanisms. There is an urgent need for new tools for quantitative evaluation of the dust distribution, transport and deposition. The Terra spacecraft launched at the dawn of the last millennium provides first systematic, well calibrated multispectral measurements from the MODIS instrument, for daily global analysis of aerosol. MODIS data are used here to distinguish dust from smoke and maritime aerosols and evaluate the African dust column concentration, transport and deposition. We found that 240±80 Tg of dust are transported annually from Africa to the Atlantic Ocean, 140±40 Tg are deposited in the Atlantic Ocean, 50 Tg fertilize the Amazon Basin, 4 times as previous estimates thus explaining a paradox regarding the source of nutrition to the Amazon forest, 50 Tg reach the Caribbean and 20 Tg return to Africa and Europe. The results are compared favorably with dust transport models for maximum particle diameter between 6 and 12 µm. This study is a first example of quantitative use of MODIS aerosol for a geophysical research.
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