China’s cities are not only growing in population and infrastructure, but they are also sinking at an alarming rate. A new study published in the journal Science reveals that an estimated 16 percent of the country’s major cities are losing more than 10 millimeters of elevation per year, with nearly half losing more than 3 millimeters per year.
The combination of subsidence and sea level rise could result in a quarter of China’s urban coastal land sitting below sea level in the next 100 years. This poses a significant threat to the country’s cities and their residents.
The study, which used state-of-the-art radar data from satellites, found that subsidence in these cities is primarily caused by the weight of buildings and infrastructure, as well as activities like pumping water from aquifers, oil drilling, and coal mining.
Beijing and Tianjin are among the cities sinking the fastest, with uneven subsidence leading to potential damage to buildings and infrastructure. Similar problems exist in other countries, including the United States.
Experts warn that current adaptation strategies and resiliency plans do not adequately address land subsidence, which is a widespread issue that is often overlooked. The key to minimizing damage is limiting groundwater extraction, as demonstrated by cities like Shanghai and Tokyo.
While it may be difficult to completely stop subsidence, it is crucial for cities to adapt to sea level rise and sinking land in order to mitigate the potential risks and consequences. The findings of this study serve as a wake-up call for policymakers and urban planners to address this pressing issue before it’s too late.
