A report released by World Bank has cautioned that a gradual rise in global temperatures by 2 degrees Celsius during the next few decades could cause widespread food shortage, unprecedented heat waves and more intense cyclones in tropical regions, threatening to trap millions of people in poverty.

According to the report, if the present trend continues, drought and heat could leave 40 percent of land that grows maize, unsuitable for the crop. The rising temperatures may also cause major loss of Savanna grasslands, threatening pastoral livelihoods in Sub-Saharan Africa by 2030.

In the Indian sub-continent, change in uniformity of monsoon could bring a major crisis in the region. Devastating floods like that of Pakistan in 2010 could become a common affair. Frequent droughts in many parts of India could lead to widespread food shortage. By the 2050s, the undernourished population in the sub-region is projected to increase by 25 percent to 90 percent as compared to the present scenario.

The report said that people in cities with a large population but limited basic services are highly exposed to extreme weather events such as storms and flooding.