A new study by Stanford University looked at the effects of climate change on global economic inequality. The study found that the gap between the economic output of the world’s richest and poorest countries is larger today than it would have been without global warming.
The warming climate has enriched cooler countries like Norway and Sweden while dragging down economic growth in warm countries such as India and Nigeria. The results of the study showed that most of the poorest countries on Earth are considerably poorer than they would have been in the absence of rising temperatures. At the same time, the majority of rich countries are richer than they would have otherwise been.
Detailed analysis of 50 years of annual temperature and GDP measurements for 165 countries demonstrated that growth during warmer than average years has accelerated in cool nations and slowed in warm nations. Historical data clearly show that crops are more productive, people are healthier, and they are more productive at work when temperatures are neither too hot nor too cold. That means that in cold countries, a little bit of warming can help but the opposite is true in places that are already hot.
For most counties, whether global warming has helped or hurt economic growth is pretty certain. Tropical countries in particular tend to have temperatures far outside the ideal for economic growth and they are already among the poorest countries. It is less clear how warming has influenced growth in countries in the middle latitudes, such as here in the United States. Some of the largest economies are near the perfect temperature for economic output but continued warming in the future is likely to push them away from the temperature optimum.
Photo, posted November 1, 2011, courtesy of CIAT via Flickr.