Warming temperatures caused by climate change are resulting in huge chunks of ice disappearing from Greenland at such a speed that the melt has already had a significant contribution to sea level rise, according to a new study. With global warming, the island will lose much more, threatening coastal cities around the world, reports CNN.
Forty to fifty percent of the planet’s population is in cities that are vulnerable to sea rise, said the study published Monday in the Proceedings of the National Academy of Sciences, which is bad news for places like New York, Miami, Los Angeles, Tokyo, and Mumbai. Greenland’s ice sheets contain enough water to raise global sea levels by 23 feet, research shows.
For millions of years, Greenland’s ice has melted in cycles due to changes in the weather, but rising temperatures have been hard on the region, and the ice lost since the 1980s is more than has probably been lost in thousands of years. A study published in December that looked at ice core samples found that Greenland’s ice sheets have been melting at an “unprecedented rate” over the past couple decades, about 50% higher than pre-industrial levels and 33% above levels in the 20th century. Researchers found that the rate of ice loss has increased sixfold in the last fifty years — even faster than scientists thought.
Summer melt season has already begun in Greenland, according to the National Snow & Ice Data Center — more than a month ahead of schedule. Since 1972, ice loss from Greenland alone has added 13.7 millimeters (about half an inch) to the global sea level, the study estimates. The island’s ice sheet is the leading source of water added to the ocean every year, and the glaciers are starting to flow faster and break into icebergs that are moving into the ocean.