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SCATSAT-1 measures the backscattering coefficient over land surfaces, which is a function of vegetation structure, surface roughness, soil moisture content, incidence angle and dielectric properties of vegetation. Scatterometer image reconstruction techniques provide fine resolution data to explore the emerging applications over land by using ambiguous backscatter from land. In this paper, 2 km resolution products of ISRO's scatterometer SCATSAT-1 are exploited for land target detection, rice crop phenology stages detection for kharif and rabi seasons and estimation of relative soil moisture over parts of India. Temporal and spatial backscatter changes are due to seasonal and changes in Land Use Land Cover. Crop phenology stages such as transplanting, maximum tillering, panicle emergence and physiological maturity stages are identified by analysing SCATSAT-1 time series along with NDVI and findings are supported by appropriate ground truth observations and crop cutting experiment (CCE) data. The relative soil moisture change detection is validated with in situ ground truth measurements using Hydraprobe, carried for SCATSAT-1 ascending and descending passes. [ABSTRACT FROM AUTHOR]

One of the important payloads on-board the joint Indo-French Megha-Tropiques satellite is the Scanner for Radiation Budget (ScaRaB). It is dedicated for monitoring the Earth Radiation Budget (ERB) parameters at Top of Atmosphere (TOA). In this article, details of the algorithm used for computing two important ERB components, namely TOA reflected shortwave and emitted longwave fluxes from ScaRaB radiance measurements are presented along with preliminary cross-satellite validation results. The ScaRaB flux computation algorithm is similar to the one used in the ERB Experiment. The maximum likelihood estimation algorithm is used for identification of different Earth scenes and cloud types. First, the raw radiances are corrected for spectral filtering effects followed by implementation of scene-type dependent angular correction to deduce shortwave and longwave fluxes. The instantaneous TOA flux data derived from ScaRaB radiance measurements are compared with similar data available from Clouds and Earth's Radiant Energy System (CERES) onboard Aqua and Terra satellites. Preliminary comparison confined to two months period (September-October 2012) using the two satellites suggests that the ScaRaB data are in good agreement with the CERES data. The bias-corrected root mean square difference in ScaRaB longwave flux is 4.7 and 5.3 Wm-2 with respect to CERES on-board Aqua and Terra satellites respectively. For ScaRaB shortwave flux, it is 25.9 Wm-2 and 25.5 Wm-2 with respect to CERES onboard Aqua and Terra satellites respectively. A detailed comparison of ScaRaB TOA flux data with more than one-year of CERES data is already initiated. Results from the preliminary comparison exercise suggest that the ScaRaB data can be used with confidence for ERB studies. [ABSTRACT FROM AUTHOR]