Japanese summers have lengthened by about three weeks over the 42 years from 1982 to 2023, a university research group said on Saturday.The Mie University group said that due to climate change, the number of days classified as summer has increased each year, while the length of winter has remained relatively unchanged, and the average durations of spring and autumn have shortened.The group cited “the rise in sea surface temperatures due to global warming” as the main factor, warning that “the...