PLEA Network

29 May 2019, Climate Home News, Deadly Japan heatwave ‘essentially impossible’ without global warming. Study finds one of the clearest climate change signals to date in July 2018’s record high temperatures, in a result that surprised scientists. Japan’s heatwave in July 2018 could not have happened without climate change. That is the unequivocal conclusion of a report released last week, as the country battles yet another record-breaking heatwave. The July 2018 heatwave, which killed 1,032 people, saw temperatures reach 41.1C, the highest temperature ever recorded in the country. Torrential rains also triggered landslides and the worst flooding in decades. Penned by the Meteorological Society of Japan, the study is the first to establish that some aspects of the international heatwave could not have occurred in the absence of global warming. Scientists reached this conclusion by employing a technique known as event attribution (EA). The relatively new method, lead author Yukkiko Imada told Climate Home News, sought to pin down the causality of climate change in the heatwave by simulating 18 climate scenarios with and without the current 1C global warming above pre-industrial levels. They found a one in five chance of the heatwave occurring in the current climate, but almost no chance of in a climate unchanged by human activity. Read more here