Climate Change Scenarios of India with Special Emphasis on Sundarbans Delta and Western Himalayan Region

In recent times, creation of climate change scenarios at country scale as well as different homogeneous zones, and some identified vulnerable zones are more demanding for the implementation of different adaptation and mitigation strategies by the multi-level stakeholders and administrators towards combating climate change issues. An attempt was made in the present study to generate climate change scenarios over different homogeneous zones of India with special focus over two most vulnerable regions namely Western Himalayan Region (WHR) in the north and the Indian Sundarbans in the east which are technically known as “climatic hot-spots” of India. To put more reliability of the climate change results and to minimise the inherent biases of the present generation General Circulation Models (GCMs) simulations, two widely accepted downscaling methods namely Model Output Statistics (MOS) and Perfect Prognosis (PP) is utilised to develop downscaled rainfall and temperature scenarios over above-mentioned homogeneous zones and two “climatic hot spots” regions of India. In general, future downscaled projection indicates an increment in annual rainfall and temperature in all India level with varying magnitudes over different homogeneous zones. Significant warming is observed for all seasons during 1969–2009 over WHR with winter warming of 1.41 °C is substantially higher than global average changing the hydrological system of this region. Annual rainfall is found to be declined over WHR which affects the agricultural pattern and crop yield. Annual rainfall of this region is projected to increase by both representative concentration pathway (RCP) scenarios which may significantly contribute towards Sea-level-rise. However, decreased winter rainfall under RCP 8.5 may cause higher salinity in the mangrove region hampering the ecosystem.