Searing heatwaves swept across China’s vast Yangtze River basin on Wednesday, hammering densely populated megacities from Shanghai on the coast to Chengdu deep in the heartlands. More than 90 red alerts, the most severe in a three-rung warning system, were active across China as of 3:30 p.m. (0730 GMT. Most were in the Yangtze basin, which spans nearly 2,000 km (1,200 miles). Shanghai, China’s commercial capital, issued its second red alert in four days, warning of temperatures exceeding 40 degrees Celsius (104 degrees Fahrenheit). Construction and other outdoor activities are reduced or halted under a red alert, historically very rare for the city of 25 million. In Nanjing, a nearby city of over 9 million, the […]