Showing papers by "Sathianeson Satheesh published in 1997"
TL;DR: In this article, a multwavelength solar radiometer was used on a scientific cruise in the tropical Indian Ocean (TIMO) to measure the spectral optical depths of aerosol spectral data.
Abstract: Results of the studies on the characteristics of marine aerosol optical depths made in remote regions of the tropical Indian Ocean using a multiwavelength solar radiometer, taken on a scientific cruise, are presented. The dependence of the aerosol optical depths on prevailing winds in marine boundary layer and on deck level relative humidity (RH) are examined. Aerosol optical depths (τp) in far oceanic regions with marine air mass prevailing, in general, are found to increase nearly exponentially with average wind speed (Ua) as τp=τo exp(a Ua), where a = 0.16 ± 0.04. No association is seen with deck level relative humidity, as the effects of wind appear to offset the effects due to RH. The columnar size distributions retrieved from aerosol spectral optical depths reveal two modes, one at ∼0.04 μm and a secondary mode at ∼0.8 μm. The columnar mass loading estimated from the size distributions increases exponentially with wind speed and has a wind independent value of ∼28 mg m−2.
142 citations
TL;DR: In this article, the spatial and spectral characteristics of coastal aerosols and the effect of the proximity to the (urban) continent are investigated from aerosol spectral optical depths (τ pλ ) at 10 wavelengths in the range 380 to 1025 nm estimated at different locations in the near and far coastal regions of the Arabian sea adjoining the western coast of central India.
Abstract: From aerosol spectral optical depths (τ pλ ) at 10 wavelengths in the range 380 to 1025 nm estimated at different locations in the near and far coastal regions of the Arabian sea adjoining the western coast of central India, the spatial and spectral characteristics of coastal aerosols and the effect of the proximity to the (urban) continent are investigated. The Angstrom parameters are deduced from τ pλ values. A significant increase, both in aerosol optical depths at shorter (visible) wavelengths (λ≤ 600 nm) and the Angstrom wavelength exponent are observed in the near coastal regions, suggesting an increase in the (relative) concentration of sub micron particles, apparently of anthropogenic origin. The Angstrom turbidity coefficient remains nearly steady spatially, indicating a (spatially) uniform loading of large particles. DOI: 10.1034/j.1600-0889.49.issue4.7.x
58 citations