Seasonal Variability and Anomalies in Precipitation over Pakistan; a study of 2010 – 2014 Floods

Abstract:

The study is concerned with understanding and analyzing the meteorological parameter of precipitation in the region of Pakistan to establish correlation between the consecutive five year (2010 – 2014) flooding and precipitation anomalies. Temporal and spatial variations in the rainfall pattern were studied and time series analysis for one region, which was most affected by the floods, was carried out. Two precipitation products, Global Precipitation Climatology Project (GPCP) and Climate Prediction Center Merged Analysis of Precipitation (CMAP), were used for the period of January 1979 till December 2014 which showed similar patterns albeit with slightly different magnitudes. It was found that there was a strong seasonal trend in the precipitation corresponding to the summer Monsoons and winter Western Disturbances phenomenon; that there were high spatial variations across the country; and that the changing rainfall pattern and intensity caused massive flooding in the five year period under consideration. The case study for the selected region also showed that while there is a downward trend in the annual precipitation, specific months corresponding to the Monsoon period showed an upward trend and the intensity and occurrence of anomalous events have increased.