Climate change: Deadly week-long heatwaves will be up to SEVEN times more likely by 2050
If greenhouse gas emissions are allowed to continue at extreme rates, deadly could be up to seven times more likely by 2050, a study has warned. Experts led from the Swiss Federal Institute of Technology modelled the frequency of extreme temperature episodes under various future emission scenarios. They found that record-shattering heatwaves become more likely not in association with the severity of , but with the rate at which the climate heats up. The study was undertaken by climate scientist Erich Fischer of the Swiss Federal Institute of Technology (ETH Zurich) and his colleagues. 'Models project not only more intense extremes but also events that break previous records by much larger margins,' the researchers wrote in their paper. 'These record-shattering extremes, nearly impossible in the absence of warming, are likely to occur in the coming decades.' In their study, the researchers ran climate simulations to determine the likelihood of week-long, record-shattering heatwaves under various future emissions scenarios. The team found that under a high-emissions scenario, record-shattering, week-long extremes of heat will be 27 times more likely over the period from now until 2050 than they have been in the past three decades. The probability of these heatwaves will increase even further to 321 times recent rates in the period from 20512080, during which time the events will likely strike with a frequency of every 637 years in the northern midlatitudes. However, the researchers' models also indicated that record-shattering heat spells will tend to occur in spurts during periods of accelerated climate warming, and, in contrast, will be less probable in 'quiet' periods with little or no warming. 'Their probability of occurrence depends on warming rate, rather than global warming level, and is thus pathway-dependent,' the team said. Given this, they explained, if human-induced warming was successfully stabilised by aggressive mitigation, there would still be more frequent and intensive heatwaves than experienced in the past, but record-breaking extremes would be less likely. 'Just in the last month, the world has experienced temperature records being smashed in North America and devastating floods in Europe and China,' said University of Bristol climatologist Vikki Thompson, who was not involved in the study. 'It is clear that climate change is affecting the planet. The need to understand what could happen in the future is vital to allow us to adapt. 'The good news is that we can prevent the worst case shown in this study we are already on target to be below it and further reductions in emissions will reduce the risk of unprecedented extremes further. 'Studies like this show the need for clear global emissions targets, which could come out of the 2021 United Nations Climate Change Conference.' The full findings of the study were published in the journal .