Most of the analyses (especially on rainfall, temperature, extreme rainfall, sea surface temperature, meteorological droughts) are based on the data for a longer period of 110 years, 1901-2010. For some other parameters like moisture, clouds, heat waves and cold waves, atmospheric aerosols, ozone and trace gases and radiative fluxes, data of shorter period have been used. The articles documented inter-annual and decadal variability in addition to documenting long term trends of different parameters. The trends have been tested for statistical significance using standard techniques.

It is expected that the present book will be an excellent reference material for researchers as well as for policy makers. These results will be useful in interpreting future climate change scenarios over the region being projected using coupled climate models. Further analysis of these results is required for attributing the observed variability and change to natural and anthropogenic activities.