China’s Worsening Floods Highlight Extreme Weather Threat

(Bloomberg) -- Weeks of torrential rain in southern China have left millions of people without homes and caused billions of yuan in economic losses, with environmental groups warning the extreme floods are likely to become more common.

By late June, more than 12 million people across 13 provinces had been affected, according to China's Ministry of Emergency Management. The floods have killed 78 people, damaged 97,000 homes and caused 25 billion yuan ($3.6 billion) in economic losses, it said.

Videos that circulated on social media showed houses collapsing, cars afloat and crops dying in muddy, flooded fields. Multiple cities in southern China also suffered infrastructure damage. In Yangshuo, an arch bridge was almost completely underwater while roads and a railway track in Chongqing near the Qi River were submerged.

China has struggled to contain flooding in its low-lying plains for millennia and uses dikes, polders, dams and other features to manage the surges in water levels. But more unpredictable weather has made the task harder, endangering the lives of millions who live along the rivers, and environmentalists warn that more suffering will occur unless measures are taken to make infrastructure more resilient and tackle climate change globally.

“The devastating floods that we have seen are consistent with an increase in extreme weather events due to climate change,” said Liu Junyan, a Greenpeace East Asia campaigner. “There is an urgent need to strengthen early warning systems for extreme weather events, to assess future climate risks in cities and to improve flood management systems.”

The frequency of both extreme precipitation and high temperature events driven by climate change has risen steadily over the past six decades, according to a report published by China Meteorological Administration in 2019.

This year's floods are having an impact on commodities from agriculture to energy. At least 80,000 hectares of crops including rice, vegetables and fruits have been damaged in Hubei province, according to the local emergency management office. Early summer is an important time for rice to grow and if the flowers are washed away, experts say output will decrease significantly this year. Meanwhile the heavy rains are resulting in increased hydropower generation, reducing demand for coal.

There have been five rounds of heavy rainfall in China's southern provinces since early June, prompting the National Meteorological Center to issue severe rainstorm alerts for almost every day of the month. According to the agency, there will be two more rounds of heavy rain in the coming days. In late June, at least 25 major rivers exceeded flood alert levels.

Although some of the affected regions generally suffer damage from rainfall every year, this year's accumulated precipitation is double to triple the usual level, according to Chen Tao, the chief weather forecaster at China's National Meteorological Center.

Sea Levels

The global rise in sea levels, which scientists say is caused by warming temperatures, is also threatening many Chinese cities. According to the environmental ministry, the average rate of sea level rise along China's coast was 3.4 millimeters per year between 1980 and 2019, faster than the global average. In 2019, the sea level along China's coast was 72 millimeters higher than normal, said the ministry.

A study this year showed that China's Pearl River Delta, the country's manufacturing hub and home to tens of millions of people, is the world's most at-risk urban center from rising sea levels and could be under at least 67 centimeters of water by the year 2100 unless measures are taken to stop it.

Besides climate change, decades of economic development and urbanization which involve reclaiming land from lakes and wetlands have also increased the amount of damage natural disasters can incur. Wuhan, once known as the “city of 100 lakes,” has seen most of the 127 lakes that existed in 1980s now lost to reclaimed land, and it now faces one of China's most serious urban flooding problems.

“Human activities have destroyed the rivers, lakes, forest and any form of natural ‘protections' to fight floods,” said Yu Jianfeng, founder of Public Culture Center of Environmental Protection for Rivers, a non-profit organization based in Chongqing. “It's time for us to set principles on how we develop and we need to leave enough natural reservoirs to our cities to reduce the damage of floods.”

©2020 Bloomberg L.P.

With assistance from Bloomberg