(CN) – The Greenland ice sheet is melting so quickly that nearly 400 million people will be underwater within 80 years due to rising sea levels, according to a study published Tuesday.
Climate change has eaten away at the island nation of Greenland, located between the Arctic and Atlantic oceans. At nearly 660,000 square miles, the ice sheet covers roughly 80% of the island’s landmass and is one of the only permanent ice sheets outside of Antarctica.
But in the last 26 years, the ice has melted at an exponentially high rate according to the study published in the journal Nature.
The rate of loss increased from 33 billion tons of ice lost per year in the 1990s to 254 billion tons per year in the last decade, according to the study – a seven-fold increase in less than 30 years.
This massive melt accounts for 3.8 trillion tons of ice loss that contributes to rising sea levels, according to the study’s authors, some 100 polar scientists from 50 international organizations. The study’s authors are credited as the Ice Sheet Mass Balance Inter-comparison Exercise (IMBIE), which reviewed 26 surveys from 1992 to 2018. That data was the result of 11 satellite missions that analyzed volume change, flow and the gravity of the Greenland ice sheet.
Rising sea levels is one indicator of climate warning scenarios laid out by the United Nation’s Intergovernmental Panel on Climate Change (IPCC), which forecast that 360 million people will be at risk of annual coastal flooding by the year 2100.
The 2014 estimate from the IPCC forecast sea level rise ranging from 20 to 28 inches over the next 80 years. But the latest study from the IMBIE team estimates that figure could be higher, with Greenland’s ice melt expected to contribute 2 to 6 inches alone.
Ice melt peaked in 2011 at 335 billion tons of loss with intense surface melting. While researchers note a drop to about 238 billion tons since then, the rate is still 10 times higher than in the last 30 years. And 2019 could set a new high due to widespread summer melting.
The study was co-led by Andrew Shepherd of Leeds’ School of Earth and Environment.
In a statement accompanying the study, Shepherd said, “As a rule of thumb, for every centimeter rise in global sea level another 6 million people are exposed to coastal flooding around the planet.”
He added: “These are not unlikely events or small impacts; they are happening and will be devastating for coastal communities.”
A study published this October in Nature Communications found by the year 2050, southern Vietnam will be under water during high tide – including the majority of Ho Chi Minh City. Drastic shifts in the geography of several other coastal cities will be impacted according to that study, including Bangkok, Thailand; Shanghai, China; and Basra, Iraq.
But rising sea levels are already displacing cities across the globe.
Last month, the islands that make up Venice, Italy, were inundated with record floods. According to the Tide Monitoring and Forecast Centre of Venice, the city that is already sinking into the mud saw tide levels reach over 6 feet (187 cm) this year, second only to record high tide levels in 1966.