The South Asian Rapid Assessment Programme (SA RAP) initiated by the Global Change System for Analysis, Research and Training (START), and supported by the Monsoon Asia Integrated Regional Studies (MAIRS), has for the first time attempted to synthesize the scientific understanding generated so far by the global change research studies carried out in and for the South Asian region in a holistic manner. This book aims to encompass most components of physical and human dimensions of changes in the Earth systems (viz., climate, ecosystem, atmosphere, resources and sustainable development etc.) that are either affected, or have bearings on the environment and for which the scientific understanding has so far been generated for the South Asian region. The book has been collated in the form of different chapters dealing with specific issues. Each of these chapters has been contributed by regional researchers and sector experts. The content of this volume will cater to the needs of not only the global change researchers but also academia.