Scientists from the University of East Anglia (UEA) and the Virginia Institute of Technology are sounding the alarm about the extent of land subsidence in Chinese cities, which threatens 270 million people.
A study published in New Voice, is based on the analysis of satellite data of 82 Chinese cities with a population of almost 700 million people.
The results show that 45% of urban areas are subsiding, with 16% falling at a rate of 10 mm per year or more. This can lead to serious consequences, including damage to buildings and infrastructure, flooding of coastal areas and mass migration.
The problem is particularly acute in coastal cities, where land subsidence is exacerbated by climate change and sea level rise.
“If we don’t respond properly, it could have catastrophic consequences,” warns Professor Robert Nicholls of UEA.
Scientists point out that subsidence is mainly caused by anthropogenic factors, such as groundwater pumping.
At the same time, they cite the examples of the Japanese cities of Osaka and Tokyo, where strategies to reduce the effects of subsidence have been successfully applied.
“We need a global response to this problem and support for appropriate measures at the national level.”, – urge the authors of the study.
They highlight the need to move from measurement to action and develop strategies with urban planners to counter this threat, especially in vulnerable coastal cities.
