NEW DELHI: The mean temperature in India rose by 0.2 degree Celsius every decade between 1971-2007 with minimum temperatures rising more than maximum temperatures, which increased 1.02 degree Celsius in 100 years. While the trends show evidence of warming, there is, however, no conclusive proof that these are linked to human-induced climate change.
The most alarming findings in the report are the predictions it makes based on scenarios that greenhouse gas emissions would continue to rise unchecked over the coming decades. Projections show that total monsoon rainfall could rise between 9-16% by the end of 21st century. By that time, annual mean temperatures could rise by 3.5-4.3 degree Celsius with 1.7-2 degree rise taking place as early as 2030s.
The report says the number of rainy days could decrease but rain could become more intense – thereby causing more damage – almost all across the country. Both the minimum and maximum temperatures recorded in a day will rise, according to the findings. Areas in Rajasthan and Kutch could see more than a 4-degree rise in maximum temperatures by as early as 2020s. A similar rise could take place in more than half the country by 2080.
Night temperatures are projected to rise by 4.5 degrees across a large part of the country by 2050 and the jump could spread to almost the entire country by 2080 Separate studies have been conducted to measure the impact of increasing GHG gases on water availability in river basins and on agricultural productivity. The government assessment notes, “Water scarcity levels will be crossed in Cauvery, Mahi, Sabarmati and west-flowing rivers of Kuch, Sau and Luni, while Ganga, Tapi and Narmada basins will hit water stress limits.”
The report says, “Ganga downstream, Brahmaputra and Surma-Imphal show high vulnerability to climate change in the northern and eastern basins.” Ganga upstream and Mahanadi will also become vulnerable by 2070, it says. The impacts of unchecked emissions on agriculture are also worrisome. The worst hit could be one of the two major grain crops – wheat.