Agricultural Drought Assesment Through Geospatial Techniques at Raichur District Karnataka India

Abstract

newline i newlineAbstract newlineDrought is a natural feature of weather and is experienced in almost all climatic regions with newlinevarying frequency, severity and duration. It can be described as a short term disparity in water newlineavailability consisting of a persistent lower than average rainfall of uncertain frequency, duration newlineand severity, of unpredictable or extremely hard to predict occurrence, resulting in diminished newlinewater resources availability. When the severity exceeds it starts affecting the soil moisture newlinecausing stress to the growing crops and it leads to the agricultural drought. Agriculture is very newlinemuch affected by the drought for the past fifty years and scientists all over world are conducting newlineresearch to develop more breeds of drought resistant crops as well as drought resistant soil. newlinePrecipitation being the main source of water in agriculture, a small change in its pattern or delay newlinein seasonal arrival causes loss in the crop yield. newlineRemote sensing has emerged as important and efficient tool for the detection, monitoring, newlineassessment and management of drought. The availability of the spatial and temporal coverage of newlinesatellite data makes it more useful and reliable for the management of emergency situations other newlinenatural disasters like floods, landslides etc. Drought indices evaluate the departure of newlinemeteorological variables in a given time interval from the standard conditions and are used as newlinemonitoring tools and operational indicators for planning. Several drought indices have been newlinedeveloped, most of them based only on precipitation, some based on precipitation and newlineevapotranspiration (ET), and others referring to runoff and vegetation conditions. The newlineNormalized Difference Vegetation Index (NDVI) is a numerical indicator that uses the visible newlineand near-infrared bands of the electromagnetic spectrum, and is adopted to analyze remote newlinesensing measurements and assess whether the target being observed contains live green newlinevegetation or not and is most commonly used one. newlineMODIS data products have now numerous application