Jul 26, 2020 (Nikkei) - The risk of deadly downpours has risen Japan in recent years due to global warming, adding to people's worries this summer, on top of the coronavirus pandemic.
Heavy rains, floods and landslides this month have destroyed more than 1,000 residential buildings, killing at least 78 people across Japan, mostly in the country's southwestern Kumamoto Prefecture.
For the 24 hours through the morning of July 4, the city of Ashikita in northern Kumamoto was hit by torrential rain said to "occur once in 50 or 100 years," according to the National Research Institute for Earth Science and Disaster Resilience, or NIED. Some cities in the region got more than a month's worth of precipitation overnight.
Devastating rainfall and floods have become more common in recent years, highlighting the threat of climate change. Last year, typhoons in October triggered a deluge that would normally occur only once in "over 100 years" in parts of Nagano, Fukushima and Miyagi prefectures, according to NIED.
The island of Kyushu, hit hardest by this year's downpours, was soaked with flooding rains just three years earlier, leaving 42 people dead or missing. In July 2018, there was also widespread flooding in southern Japan.
Data from the Japan Meteorological Agency shows downpours are becoming more frequent. For the 10 years from 2010 to 2019, rainfall in excess of 50 mm an hour occurred 327 times a year on average, compared with 226 times between 1976 and 1985, an increase of 40%. Extreme rainfall events with precipitation of more than 400 mm per day -- the level likely to cause landslides or floods -- rose 170% over the same period.
