According to a study by scientists at the National Center for Atmospheric Research (NCAR) in Boulder, Colorado, if climate change continues its current progression, summers between 2061 and 2080 will be hotter than the hottest on record to date, at 80% of probabilities. Those will happen in almost all regions of the world, with the exception of Antarctica, which has not been included in the study. If greenhouse gas emissions can be reduced, the probability will drop to 41%.
For the NCAR scientist, Flavio Lehner, lead author of the study, extremely hot summers always pose a challenge for society, as they increase the risk of suffering health problems, they can damage crops and aggravate the consequences of drought. Summer periods with extreme temperatures are a true test of our ability to adapt to rising temperatures.
The study, included in a special issue of the journal Climate Change that will focus on quantifying the benefits of reducing greenhouse gas emissions, has been funded by the National Science Foundation (NSF) and the National Science Foundation from Switzerland. Scientists have relied on simulations that assume that greenhouse gas emissions do not decrease , as well as on other simulations under the assumption that society manages to reduce emissions.
Using these simulations, the experts were able to analyze the range of summer temperatures forecast for the future in scenarios similar to the current one and in scenarios with fewer emissions. This is the first time that heat risk, record temperatures and their dependence on the rate of greenhouse gas emissions have been comprehensively assessed . The scientists compared the results of actual summer temperatures recorded between 1920 and 2014 and 15 sets of simulated summer temperatures for the same period. Thus they established a wide range of temperatures that could have occurred naturally under the same conditions, including concentrations of greenhouse gases and volcanic eruptions. The results show that between 2061 and 2080, summers in large areas of North and South America, Central Europe, Asia and Africa are more than 90% likely to be hotter than any summer in the historical record if emissions continue unabated. That means that virtually every summer would be as hot as the hottest to date.
Reducing emissions would lower the overall likelihood of future hotter summers than any in the past, but it would not translate into evenly distributed benefits. In some regions, such as the East Coast of the United States and much of the tropics, the probability would remain above 90%, even if emissions are reduced. But reducing emissions could have a considerable benefit for other regions of the world. Parts of Brazil, central Europe and eastern China would experience a reduction of more than 50% in the risk that future summers will be hotter than the historical range. Since these areas are densely populated, a large part of the world’s population would significantly benefit from climate change mitigation. “It is often overlooked that the majority of the world’s population lives in regions that will experience comparatively rapid increases in temperatures,” according to the study authors.
