Each year, Indian summer monsoon season begins in June and ends in September. Surface winds blow from the southwest during this season. The Indian summer monsoon typically covers large areas of India with western and central India receiving more than 90% of their total annual precipitation during this period, and southern and northwestern India receiving 50%-75% of their total annual rainfall. Overall, monthly totals average 200-300 mm over the country as a whole, with the largest values observed during the heart of the monsoon season in July and August. In all total, India receives about 870 mm of rainfall in a normal summer monsoon season. This summary discusses the effects of climate change on the frequency, mean rainfall, duration and the variability of the Indian Monsoon. East Asian Monsoon in the southeastern part of Asia is not discussed in this summary. Changes in monsoon characteristics are mainly inferred from climate model simulations submitted to the Intergovernmental Panel on Climate Change (IPCC)'s Fourth Assessment Report (AR4). It should be cautioned that there is a large range in the results from these models. For instance, the range of mean monsoon precipitation as simulated by the AR4 models over India is from 500 mm to 900 mm for the present-day climate (Kirpalani et al. 2006).

Variability of the Indian summer monsoon has increased significantly since the 1950s. For several regions across India, this means an increase in long dry periods with low or no rainfall, intermittent with short, intense spells of rainfall. These changes are particularly significant for the western, central and eastern states of India where more than 55% of the cultivated area is largely rainfed and where the adaptive capacity is the lowest. The large-scale secular changes in monsoon rainfall are attributed to the increase in global emissions of greenhouse gases and air pollutants. At the same time, local changes through urbanization, land use changes and deforestation have brought in a non-uniform response in these rainfall trends. Changes in the onset, duration and intensity of the rainfall call for a reassessment of the crop calendar and climate resilient measures for the food-water-energy sectors of the country. Global warming has also altered the relationship between sea surface temperatures and other predictors of monsoon rainfall, introducing increasing challenges and uncertainties in the monsoon forecasts. Climate projections indicate a further increase in the monsoon variability and a shortening of the rainy season in the future, though there is considerable disagreement between model simulations.

This open access book discusses the impact of human-induced global climate change on the regional climate and monsoons of the Indian subcontinent, adjoining Indian Ocean and the Himalayas. It documents the regional climate change projections based on the climate models used in the IPCC Fifth Assessment Report (AR5) and climate change modeling studies using the IITM Earth System Model (ESM) and CORDEX South Asia datasets. The IPCC assessment reports, published every 6–7 years, constitute important reference materials for major policy decisions on climate change, adaptation, and mitigation. While the IPCC assessment reports largely provide a global perspective on climate change, the focus on regional climate change aspects is considerably limited. The effects of climate change over the Indian subcontinent involve complex physical processes on different space and time scales, especially given that the mean climate of this region is generally shaped by the Indian monsoon and the unique high-elevation geographical features such as the Himalayas, the Western Ghats, the Tibetan Plateau and the adjoining Indian Ocean, Arabian Sea, and Bay of Bengal. This book also presents policy relevant information based on robust scientific analysis and assessments of the observed and projected future climate change over the Indian region.

This book provides a synthesis of research findings, in terms of strategic knowledge outcomes regarding emergence of recent regional climate signals, implications for impacts assessment, and mitigation and adaptation response, relevant in the Indian context. The first part discusses evidence of climate change and its underlying scientific processes across India, chiefly focusing on impacts that are already visible and attributable to anthropogenic activities. The latter part deals with the responses to climate change, highlighting the mitigation and adaptation strategies in various sectors and communities. The book presents a concise interpretation, distilling practical recommendations and policy prescriptions at national and sub-national levels. It serves as a reference point for understanding scientific advances and persisting uncertainty, future vulnerability and response capacity of interlinked human and natural systems, pertaining to India. It is an excellent resource for policy makers and industry watchers in addition to the research fraternity.

This is a timely, interdisciplinary scientific overview of the atmosphere, the ocean and the land surface as it interacts with physical, chemical and biological processes. The high level of detail sets it apart from other studies of monsoon meteorology. The text includes analysis of paleoclimate records, human influences on the monsoon climate and the economic impacts of the monsoon on economies and to human health.

This open access book discusses the impact of human-induced global climate change on the regional climate and monsoons of the Indian subcontinent, adjoining Indian Ocean and the Himalayas. It documents the regional climate change projections based on the climate models used in the IPCC Fifth Assessment Report (AR5) and climate change modeling studies using the IITM Earth System Model (ESM) and CORDEX South Asia datasets. The IPCC assessment reports, published every 6–7 years, constitute important reference materials for major policy decisions on climate change, adaptation, and mitigation. While the IPCC assessment reports largely provide a global perspective on climate change, the focus on regional climate change aspects is considerably limited. The effects of climate change over the Indian subcontinent involve complex physical processes on different space and time scales, especially given that the mean climate of this region is generally shaped by the Indian monsoon and the unique high-elevation geographical features such as the Himalayas, the Western Ghats, the Tibetan Plateau and the adjoining Indian Ocean, Arabian Sea, and Bay of Bengal. This book also presents policy relevant information based on robust scientific analysis and assessments of the observed and projected future climate change over the Indian region.

This book presents a global overview examining monsoon variability in South Asia, Australian, South America and North American, as well as a focus on glaciers and monsoon systems. Monsoon systems are important components of the Earth's climate and play fundamental roles in water and energy balances. The variability and changes in the monsoons affect millions of people and the economies of many countries. This book presents the physical mechanisms involved with monsoon systems, including recent modeling advances addressing climate changes and future projections. The Monsoons and Climate Change will be of interest to both graduate students and researchers.