Variability in rainfall and temperature regimes of the Brahmaputra Valley of Assam

Data from seven stations of the Brahmaputra Valley of Assam were analysed for evaluation of variability in rainfall and temperature regimes. Long term data on annual and seasonal rainfall, annual maximum, minimum and average temperatures of these stations were included in the analysis. The analysis showed that except Dibrugarh, Nagaon and Dhubri, total annual rainfall is on the declining trend in all the stations. Mann-Kendall rank statistics revealed that this decreasing trend rate in the annual rainfall at Jorhat is significant at 5 per cent level. The annual maximum, minimum and mean temperatures showed an increasing trend at Dibrugarh, Lakhimpur, Jorhat and Guwahati and a decreasing trend at Tezpur and Nagaon. The increasing trend of temperatures was found to be significant at Dibrugarh, Lakhimpur and Guwahati.