South China Sea level has risen by 150 mm since 1900: study

BEIJING, March 28 (Xinhua) -- Chinese researchers have reconstructed the history of the South China Sea's sea-level shift using local corals and found that the sea level has risen by 150 mm since 1900.

The Ganquan Island of Xisha Yongle Islands is seen in south China's Hainan Province, April 23, 2017. (Xinhua/Guo Cheng)

The study, carried out by researchers from the South China Sea Institute of Oceanology under the Chinese Academy of Sciences (CAS) and other institutions in the country, focused on Porites coral, a wide-spread coral in the South China Sea with a high growth rate, clear annual growth layer and sensitive response to the change of seawater environment.

The researchers analyzed the correlation mechanism between the oxygen stable isotopes of Porites coral and sea level, sea surface salinity, sea surface temperature and rainfall of the South China Sea, and reconstructed the sea level record at an annual resolution.

The study showed that the sea level fell by 0.73 mm per year from 1850 to 1900, and then rose by 1.31 mm per year from 1900 to 2015. The sea-level rise in the South China Sea has accelerated, rising by 3.75 mm per year since 1993.

The study found that the sea-level changes in the South China Sea may be the result of a combination of solar activity and greenhouse gases from 1850 to 1950, and greenhouse gases may have been the dominant factor behind the rapid rise of sea level since 1950.

The study was published in the journal Palaeogeography, Palaeoclimatology, Palaeoecology.