Large clouds of smoke billow from Japan’s most famous mountain. In no time, volcanic ash spreads to the heavily populated capital of Tokyo, fogging up the air and blanketing buildings and vehicles.

Mount Fuji, the country’s tallest summit, is revered for its snowy peak. A snowfall reported on Wednesday ended its longest snowless period in 130 years. By Yan Zhuang and Hisako Ueno Hisako Ueno ...