Summers In Coming Years Will Be Hotter Than Ever, Study Finds

In 50 years from now, people across the globe will experience extremely hot summers, hotter than any summer experienced till date, a new study has found.

According to the study conducted by scientists at the National Center for Atmospheric Research (NCAR) in Boulder, there's an 80 percent chance that summers between 2061 and 2081 will be warmer than the hottest on record if greenhouse gas emissions aren't reduced. However, a reduction in greenhouse gas emissions drops the probability down to 41 percent.

"Extremely hot summers always pose a challenge to society," said NCAR scientist Flavio Lehner, lead author of the study.

Lehner added that extreme temperatures can increase the risk for health issues as well as damage crops and deepen droughts. He said that such hot summers will turn out to be a true test of the world's adaptability to rising temperatures.

For the study, the research team used two existing sets of model simulations to investigate what future summers would be like.

The two model simulations were created by running the NCAR-based Community Earth System Model 15 times, with one simulation assuming that greenhouse gas emissions remained the same versus a reduction. The study was funded by the U.S. National Science Foundation and the Swiss National Science Foundation.

"This is the first time the risk of record summer heat and its dependence on the rate of greenhouse gas emissions have been so comprehensively evaluated from a large set of simulations with a single state-of-the-art climate model," said NCAR scientist Clara Deser.

The results found that summers between 2061 and 2080 in large parts of North and South America, central Europe, Asia, and Africa will have more than 90 percent chance of being warmer than any summer in the historic record if greenhouse gas emissions are not controlled.

On the other hand, drop in emissions will also reduce the chances of hot future summers. Parts of Brazil, central Europe, and eastern China would probably see a drop of more than 50 percent in the chance that future summers would be hotter than the historic range. However, in some regions, including the U.S. East Coast and large parts of the tropics, the chances would remain above 90 percent, even if emissions were reduced.

The study findings will be published in an upcoming special issue of the journal Climatic Change.