Global warming is seen as the latest threat to lower the production of India’s — and Asia’s — key staple by at least 7% (over pre-determined levels) by 2020 and to a maximum of 60% by the end of the century.

The threat of increasingly high temperatures to rice — now the principal crop for the country’s food security with 44.6 million ha area and 89 million tonnes in production — as a mammoth problem.

Temperature is a major determinant of crop development and growth. Studies show that rice yields would dip 10% for every 1º C increase in minimum temperature during the growing season.

Climatologists expect global mean air temperatures to go up 1.4-5.8º C by the end of the century depending on changes in greenhouse gas concentrations. In the worst case scenario, that could mean at least 60% reduction in yield per ha by the end of the century.