How Record Rain and Officials’ Mistakes in China Led to Drownings on a Subway

Christopher Burt, a weather historian for Weather Underground, a forecasting subsidiary of I.B.M., said it was the heaviest single hour of rainfall reliably measured in the center of a major city anywhere in the world.

“The Zhengzhou and Manhattan downpours show that climate change means that existing calculations of the frequency of torrential rains may no longer be valid,” he said.

The Zhengzhou Metro subway system, including its pumps, drainage ditches and pipes, was designed to meet central government drainage standards — but only for the type of storm that, under earlier assumptions, should have had a one-in-50 chance of occurring in a given year.

Article source: https://www.nytimes.com/2021/09/25/world/asia/china-floods-subway-train.html