By Mark Kaufman
Oddur Sigurðsson, a geologist in the Icelandic Meteorological Office, declared the largely vanished Okjökull glacier dead in 2014.
Five years later, on August 18, Sigurðsson and others will hike to the summit of the cone-shaped volcano where the glacier once thrived and leave a metal memorial in its place. Okjökull is recognized as the first Icelandic glacier lost to climate change. But for those of us who can’t make the hike, satellite image comparisons taken by the U.S. Geological Survey’s Landsat satellites show Okjökull’s dramatic recession between 1986 and 2019.
The glacier’s disappearance, however, isn’t unique. Glaciers are retreating all over Iceland (and, it should be noted, the world).
“The condition of the glaciers is getting poorer and poorer,” Sigurðsson said.
He has now documented the disappearance of 56 of the 300 smaller glaciers in the northern part of Iceland. But Okjökull is by far the largest of these glaciers to vanish, he noted.
Glaciers are in retreat in almost every portion of the world on every continent except Australia, which has no glaciers. As temperatures warm, notably at lower elevations where it’s naturally warmer, the rivers of ice predictably recede and thin.
“We’re not trying to figure out whether the glaciers will melt in the future,” Alex Gardner, a NASA glaciologist, told Mashable in June. “We’re just trying to find out how much and how fast.”
Eighteen of the 19 warmest years on record have occurred since 2001. June 2019 was the warmest June in 139 years of record keeping. And this July was likely the warmest month ever recorded, according to European Commission data.
Icelandic geologists estimate that Okjökull occupied around 16 square kilometers (6 square miles) in 1890. By 1945 it dwindled to 7 square kilometers. “By 1973 it was 5 [km],” said Sigurðsson. “2000 was 3.4. 2012 was 0.7.” (NASA refers to a 1901 geological map for different historical glacier estimates, but Sigurðsson noted that the map isn’t reliable).
Two years later, he declared Okjökull dead.
The crater atop the volcano is still filled with snow this August, some of which has melted into a li