Results of expedition studies of the spatiotemporal variations in the aerosol optical depth (AOD) of the atmosphere during the 42nd cruise of RV “Akademik Boris Petrov” along the route from Singapore to Kaliningrad (via Suez Canal) are discussed. It is shown that the highest atmospheric turbidities were observed over the Arabian Sea (due to the outflows of fine-mode aerosol from Hindustan) and the Red Sea (due to the outflows of dust aerosol), where the average AODs in the region 0.5 µm were 0.355 and 0.304, respectively. A considerable aerosol turbidity is also characteristic for the atmosphere in the Strait of Malacca, burdened by aerosol outflows from the direction of Sumatra and Western Malaysia (average AOD is 0.262). Different aerosol content is noted in the neighboring equatorial regions of the Indian Ocean: the average AOD in the middle of the ocean, more remote from the contents, turned out to be a factor of 1.5–2 larger than near Sumatra. All tropical zone of the Indian Ocean is characterized by high values of Ångström selectivity exponent (1.08–1.18), indicating a predominating contribution of fine-mode aerosol to AOD.
aerosol optical depth, Indian and Atlantic Oceans
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