SOURCE: National Geographic and Phys.org
DATE: April 8, 2019
SNIP: Like an ice cube on a hot summer day, many of Earth’s glaciers are shrinking.
Last January, a study in Nature Climate Change showed the world’s glaciers are the smallest they’ve been in human history, revealing radiocarbon material that hasn’t been exposed for 40,000 years.
Now, new research published in Nature quantifies how much the world’s lost glaciers have contributed to rising sea levels.
Glaciers have lost more than 9 trillion tons (that is 9,625,000,000,000 tons) of ice between 1961 and 2016, which has resulted in global sea levels rising by 27 millimeters in this period. The largest contributors were glaciers in Alaska, followed by the melting ice fields in Patagonia and glaciers in the Arctic regions. Glaciers in the European Alps, the Caucasus and New Zealand were also subject to significant ice loss; however, due to their relatively small glacierized areas, they played only a minor role when it comes to the rising global sea levels.
They found mountain glaciers contribute roughly a third of measured sea-level rise—the same contribution to sea-level rise as the Greenland ice sheet and more than the contribution of the Antarctic ice sheet. Their research also highlighted that many of the world’s glaciers may disappear in the next century.
The global mass loss of glacier ice has increased significantly in the last 30 years, and currently amounts to 335 billion tons of lost ice each year. This corresponds to an increase in sea levels of almost one millimeter per year.