CATASTROPHE DISASTER IN CHINA-Nearly half of China’s major cities are sinking, researchers say
According to a study of nationwide satellite data published on Friday, over half of China’s main cities are experiencing “moderate to severe” subsidence, placing millions of people at risk of flooding, particularly as sea levels rise.
The authors of the report, published in the journal Science, discovered that 45% of China’s urban terrain was sinking faster than 3 millimeters per year, with 16% sinking more than 10 mm per year, driven not only by dropping water tables but also by the sheer weight of the built environment.
With China’s urban population currently exceeding 900 million people, “even a small portion of subsiding land in China could therefore translate into a substantial threat to urban life,” stated a team of academics led by Ao Zurui of South China Normal University.
Subsidence now costs China more than 7.5 billion yuan ($1.04 billion) per year, and within the next century, about a fourth of coastal land might be lower than sea levels, placing hundreds of millions of people at risk of flooding.
“It really brings home that this is a national problem for China and not just one or two places,” said Robert Nicholls of the University of East Anglia’s Tyndall Centre for Climate Change Research. “And it is a microcosm of what is happening around the rest of the world.”
Tianjin, a northern city with a population of over 15 million people, was designated as one of the hardest damaged. Last year, 3,000 people were evacuated due to a “sudden geological disaster” that investigators blamed on both water depletion and geothermal well building.
Many of China’s historic coal areas have suffered as a result of overmining, with officials being needing to inject concrete into the crumbling shafts to support the ground.
The problem is not exclusive to China. A separate research published in February stated that around 6.3 million square kilometers (2.4 million square miles) of land throughout the world was at risk. Indonesia is one of the worst-hit countries, with major areas of the city, of Jakarta, now submerged.
