Indian economy 31% smaller than what it would have been without global warming - Study

India’s economy is now 31% smaller than it would have been in the absence of global warming, a new study assessing the impact of climate change on economic growth has found.

The impact of temperature changes may seem small from year to year but they can yield dramatic gains or losses over time, highlight climate scientists from Stanford University who published their findings in peer-reviewed journal Proceedings of the National Academy of Sciences (PNAS).

While the biggest greenhouse gas emitters, including the US, have an average of 10% higher per capita GDP today than they would have in a world without warming, the lowest emitters have been dragged down by 25%, showed the analysis carried out over the last 50 years.

According to the study, global warming from 1961 to 2010 decreased the wealth per person in the world's poorest countries by 17% to 30%.

“It is a huge loss to where these countries would have been otherwise,” said climate scientist and lead author Noah Diffenbaugh, “Our results show that most of the poorest countries are considerably poorer than they would have been without global warming. At the same time, the majority of rich countries are richer than they would have been.”

According to the study, the gap between the group of nations with the highest and lowest economic output per person is now nearly 25% larger than it would have been without climate change. This would widen the economic inequalities between countries, which has decreased in recent decades, says the study.

"Crops are more productive, people are healthier and we are more productive at work when temperatures are neither too hot nor too cold," said co-author and earth scientist Marshall Burke.

While rising temperature is dragging down the economic growth of warmer countries like India, colder countries like Norway and Sweden would continue to receive cumulative economic benefits.

Climate scientists had analyzed 50 years of average annual temperatures and GDP measurements for 165 countries, including India, and compared it with data from 21 global climate models.

The models helped them to isolate how much each country has already warmed up due to human activities and what each country's economic output might have been had temperatures not risen. The team calculated more than 20,000 versions of what each country’s annual economic growth rate could have been without warming.

The analysis offers a new measure of the price various countries have paid due to global warming, especially at a time when climate policy negotiations face roadblocks over questions of how to equitably divide responsibility to limit warming.