Analysis of temperature variability over north-west part of India for the period 1970–2000

The main aim of this study was to investigate the temporal trends in maximum ( T max ), minimum ( T min ) temperature and diurnal temperature range (DTR) at annual and seasonal basis for seven sites in north-west region of India. The analysis was carried out for period of 31 years (1970–2000). The magnitude of trends and their significance were determined using Sen’s slope and Mann–Kendall methods. Additionally, persistence analysis of annual average DTR and mean temperature ( T mean ) has been carried out using cumulative annual mean (CAM) method. It is clear from the results that during last three decades the majority of sites showed decrease/(increases) in DTR/( T min ) trends for seasonal and annual time scale. While, trends in annual and seasonal T max were observed insignificant. CAM analysis demonstrated that T mean has increased consistently since 1987–1988 onwards at majority of the sites. Further, correlation analysis revealed that rainfall along with potential evapotranspiration may be one of the important reasons for observed DTR decrease.