Study of frequency of anomalies in arrival of late or early Monsoon and Western Disturbances due to climate change in Bahawalpur city from 1960-2012

Abstract

Monsoon is the major system that brings heavy rainfall in South East Asia. Its timely arrival brings prosperity to the inhabitants while its delay or early arrival may cause disastrous droughts or floods. Global warming is disturbing the climatic factors and monsoon rainfall is not indifferent. Data of average monthly rainfall for 52 years from 1960-2012 was collected from the Meteorological Department of Pakistan. Global warming is agreed upon the phenomenon, hence its effects on the rainfall pattern is sure as these two variables are interlinked. This study is going to focus on the anomalies occur in rainfall pattern of monsoon and winter rainfall called Western Disturbances. This single variable was plotted decade wise to note the number of extreme rainfall on decadal time scale using an Excel worksheet. Two decades were plotted on one graph and summer and winter months are plotted on different graphs. At least one conspicuous peak value can be seen in each decade in both winter and summer rainfall. The findings of this study reveal that in the last 3 decades the anomalies are more frequent than the previous decades.