Sea level rise is on pace with the worst-case climate model scenarios

Sea level rise due in part to the melting of the Antarctic and Greenland Ice Sheets is currently on pace with the worst-case scenarios that are projected by some climate models, according to a new study led by the Centre for Polar Observation and Modeling.

Global sea levels have increased in the most part through a mechanism called thermal expansion, which means that volume of seawater expands as it gets warmer. The world's oceans are warming due to climate change. However, in the last five years, ice melt from the ice sheets and mountain glaciers has surpassed thermal expansion as the main cause of rising sea levels, according to the University of Leeds report.

Based on current rates of sea level rise due to the melting of ice sheets, global sea levels may rise an additional 17 centimeters (6.7 inches) by 2100. This would expose an additional 16 million people to annual coastal flooding as the frequency of storm surge flooding in many of the world's largest coastal cities would double.

Currently, the world's oceans are rising at an average rate of 4 millimeters per year. Since the 1990s, the melting of the Greenland Ice Sheet has contributed 10.6 mm to sea level rise, while Antarctica has contributed 7.2 mm.

Key excerpts from the University of Leeds report.....

"Although we anticipated the ice sheets would lose increasing amounts of ice in response to the warming of the oceans and atmosphere, the rate at which they are melting has accelerated faster than we could have imagined,” said Dr. Tom Slater of the University of Leeds, who is the lead author of this study.

“The melting is overtaking the climate models we use to guide us, and we are in danger of being unprepared for the risks posed by sea level rise.”