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Coast of Qingdao in east China's Shandong province
Photo: STR/AFP
With the increase in global temperature, sea levels are also rising around the world.
An evaluation of sensor and satellite data in the "Journal of Geophysical Research: Oceans" shows that China is particularly badly affected.
According to experts, various factors contribute to this.
First the "Guardian" had reported.
According to the analysis, the sea off China's coast rises by an average of 3.9 millimeters per year, and in some places it is even 5 millimeters.
For comparison: Worldwide, the average increase from 2006 to 2015 was 3.6 millimeters per year, from 1901 to 1990 it was only 1.4 millimeters per year.
So the global sea level is rising faster and faster.
Several possible reasons
At first glance, the regional differences in sea level are hardly apparent.
The oceans are connected - water exchange takes place.
But it's not quite that simple, according to Dongxu Zhou, the experts at the Ministry of Natural Resources in Qingdao in the eastern Chinese province of Shandong.
They see several possible causes for the above-average sea level rise along China's coast.
The sea in the region has also warmed up more than the global average.
"Increasing temperatures lead to an expansion of water and a higher sea level, even if the mass remains the same," the study states.
At the same time, according to the experts' analysis, the air pressure in the region has decreased.
By 1.6 pascals per year between 1980 and 2019.
The less air pressure there is on the ocean, the more it can expand.
Taken together, surface water warming and pressure drop along the Chinese coast could explain a 1.5 millimeters-a-year rise in sea levels between 1993 and 2019, the research team said.
Water ingress from rivers, wind and currents
According to the evaluation, the amount of water entering the sea off the coast of China from rivers is also increasing.
"China has some of the largest rivers in the world," writes the specialist team, naming the Yangtze, the Yellow River and the Pearl River.
This also contributes to sea level rise.
There are also regional peculiarities.
According to the study, the sea level is rising particularly off the coast of eastern China.
Wind pushes more water into this region.
In addition, there would be currents from the Formosa Strait, a strait also known as the Taiwan Strait, which interact with the so-called Kuroshio, an ocean current in the western Pacific.
According to the analysis, this also affects the sea level on China's east coast.
The particularly sharp rise in sea level in China is also a problem because around 40 percent of the population there lives in low-lying coastal areas.
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