Study warns of faster sea-level rise over coming decades
A study published in Nature Climate Change has shown that sea levels have been rising in the two decades to 2014 faster than in previous decades, and the rate of sea level rise can be expected to accelerate over the next century.
The study, led by Xianyao Chen of the University of China and Qingdao National Laboratory of Marine Science and Technology, found that, based on all sources of information, the 2.2 mm sea level rise per year in 1993 increased to 3.3mm in 2014.
The most significant contribution to the increase was the melting of the Greenland ice sheet, which rose from 5% of all sea level rise in 1993 to 25% in 2014. Melting of ice in Antarctica and other glaciers, as well as contributions from terrestrial water storage and natural climate variability, also contributed to the overall rise. The annual contribution of the Antarctic has been nearly constant, while glacier contribution has been slowly increasing.
The research paper noted that the gradual thermal recovery from the cooling effect of the 1991 Mount Pinatabu volcanic eruption has probably resulted in a thermal expansion rate of about 0.5mm per year higher than would be expected from greenhouse forcing alone.
“Thus, the underlying acceleration of thermal expansion in response to the anthropogenic forcing may emerge over the next decade or so, resulting in a further acceleration in the rate from that reported here and recent estimates.”
“The suggested acceleration and improved closure of the sea-level budget highlights the importance and urgency of mitigating climate change and formulating coastal adaption plans to mitigate the impacts of ongoing sea-level rise,” the study concluded.
The paper “The increasing rate of global mean sea-level rise during 1993–2014” is available here.