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Abstract: The AMSR-E observed brightness temperatures over India have been analyzed to study the impact of manmade radio frequency interference (RFI) sources for the two dry months April and May from 2003 to 2010. It is observed that the brightness temperature values far exceed 300K over different locations of India indicating the presence of RFI. It is pronounced over the urban areas. The regions over Punjab, Haryana and Delhi show a marked increase in spread of the RFI affected areas. The RFI affected areas have increased from 15% to 30% from 2003 to 2007 and decreased thereafter. A maximum brightness temperature of 353K is observed in April 2007 indicating very high level of RFI. [Copyright &y& Elsevier]

An algorithm for night time fog detection using satellite data was used to study 2009 and 2010 fog episodes over the North Indian plains. The algorithm employs a bispectral thresholding technique involving brightness temperature difference (BTD) between two spectral channels: 3.9 and 10.75 µm, combining radiative transfer simulations and satellite data. The prolonged fog episode of January 2010 was analysed in detail using this algorithm in conjunction with the meteorological parameters and it was found that upper tropospheric long waves passed over this region during the fog episode. These waves affect the circulation close to the surface and appear to have played an important role in the formation and persistence of fog during 2010. The present thresholding method can be used to monitor night time fog over the Indian subcontinent on an operational basis using the forthcoming geostationary satellite INSAT-3D. Copyright © 2011 Royal Meteorological Society [ABSTRACT FROM AUTHOR]