Monsoon Interannual Timeseries

All-India Summer Monsoon (June-September) Rainfall (AISMR) Anomalies during 1871-2017

The All-India area-weighted mean summer monsoon rainfall, based on a homogeneous rainfall data set of 306 raingauges in India, developed by the Indian Institute of Tropical Meteorology, is widely considered as a reliable index of summer monsoon activity over the Indian region. Long time series of this index since 1871 have revealed several interesting aspects of the interannual and decadal-scale variations in the monsoon as well as its regional and global teleconnections.