Some Aspects of the Vagaries in the Pattern of Meteorological Parameters in the State of Rajasthan in Association with the LULC Change

Abstract

Present work examined the role of the change in land use and land cover (LULC) in altering the rainfall and temperature pattern over the western part of the Rajasthan, India. For this purpose, the high-resolution gridded rainfall and surface temperature data sets prepared by IMD (India Meteorological Department) and Climatological Research Unit Time Series (CRU TS 3.21) have been utilized. An increase in surface temperature and decrease in rainfall for the principal monsoon season (JJAS) during the period 1969–2012 is observed over the study region. Statistically robust significance test establish the fact that the pattern of rainfall and surface temperature has changed significantly during the past decades. Comparative analysis of the satellite observations from Landsat 5 TM (1992) and Landsat 8 OLI/TIRS (2012) revealed a considerable LULC changes in terms of the increase in vegetated land and urban settlement areas, whereas sand and water bodies have witnessed a decrease in area. Remotely sensed images from the OLS sensor (mounted on DMSP) indicate the escalation in the urbanization signature over the study region. Present analysis reveals that the correlation between the rainfall/surface temperature and the parameters which are more influenced by the local forcing (such as relative humidity/specific humidity/upward long-wave radiation) is not significant. Therefore, it is proposed that the changes observed in the rainfall and temperature pattern over the study area is much more influenced by the large scale forcing and moderately could be associated with the LULC changes and variations in the land-atmosphere fluxes.

Keywords: IMD, CRU TS 3.2, JJAS, cumulative distribution, LULC, statistically robust, significant