Comparison of climatic variables among different climatic sub-regions of Bangladesh

Abstract

The study was conducted to compare the rate of change of selective climatic variables such as annual maximum and minimum temperature, annual total rainfall and annual average humidity among the three different climatic sub-regions (Western zone, northwestern zone and north-eastern zone) of Bangladesh. Annual averages of climatic parameters were calculated to analyze the trend lines, variation and change rate of climatic parameter during the study period. Five years moving average rainfall and humidity were also determined. It was observed that change rate of annual maximum temperature and annual average maximum temperature both were highest in north-eastern zone at the rate of 0.048 and 0.046°C per year, respectively. Highest annual minimum temperature change rate (0.003°C per year) was also found in the north-eastern zone but highest annual average minimum temperature change rate (0.034°C per year) was found in the north-western zone. Average annual rainfall was decreasing insignificantly in all the three climatic sub-regions whereas the highest change rate (21.50 mm per year) was observed in the north-eastern zone of Bangladesh. Highest annual average humidity change rate (0.113% per year) was found in the north-western zone of Bangladesh and five years moving average of annual average humidity was increasing at the highest rate of 0.132% per year in the north-western zone of Bangladesh.Bangladesh J. Sci. Res. 29(1): 63-71, June-2016