The report released here today evaluates at the likely impacts of warming between two degree Celsius and four degree Celsius on agricultural production, water resources, coastal ecosystems and cities across South Asia, sub-Saharan Africa and South East Asia.
Coastal cities like Kolkata and Mumbai are "potential impact hotspots" threatened by extreme river floods, more intense tropical cyclones, rising sea levels and very high temperatures, the report 'Turn down the heat: Climate extremes, regional impacts and the case for resilience' says.
It says shifting rain patterns will leave some areas under water and others without enough water for power generation, irrigation or, in some cases, for even drinking.
"An extreme wet monsoon that currently has a chance of occurring only once in 100 years is projected to occur every 10 years by the end of the century," the report says.
The warming will impact significant reduction in crop yields and some 63 million people may no longer be able to meet their caloric demand. Decreasing food availability can also lead to significant health problems, it warns.
In the next 20 years, a several-fold increase in the frequency of unusually hot and extreme summer months is projected.
