Unusual Late-Season Melting on Humboldt Glacier

Humboldt Glacier August 18 2023 Annotated

Satellite image of Humboldt Glacier, captured on August 18, 2023, by the Operational Land Imager on Landsat 8.

Humboldt Glacier August 27 2023 Annotated

Satellite image of Humboldt Glacier, captured on August 27, 2023, by the Operational Land Imager on Landsat 8.

Unusual late-season melting in Greenland turned the glacier’s surface into a mishmash of ice, firn, melt, and dirt.

Comparative Imagery of the Humboldt Glacier

This pair of images shows the front of Humboldt Glacier in northwest Greenland before and after melting peaked. The images were acquired on August 18 (upper) and August 27 (lower) by the Operational Land Imager (OLI) on Landsat 8.

Expert Analysis

Christopher Shuman, a University of Maryland, Baltimore County, glaciologist based at NASA’s Goddard Space Flight Center, identified and analyzed the two satellite images. Overall, “the area is a mishmash of ice, firn, melt, and dirt,” he said.

Comparison to Previous Melt Seasons

June and July saw steady, higher-than-average melting that kept the season on par with several other high melt seasons in recent decades. But the spike in late August pushed the cumulative melt area even higher, and the month ended with the second-largest cumulative melt area in the 45-year satellite record, trailing only 2012.

There have been other late-season melt events, notably in September 2010. That event pushed the season toward a larger amount of cumulative melting compared to the 2023 season so far (as of the start of September).

Implications of Late-Season Melting

Late-season melting adds to the cumulative losses within a season, but it can also affect future melt seasons. A longer melt season delays the accumulation of surface snow, which in turn can affect the intensity of melting at the start of the next season.

NASA Earth Observatory images by Wanmei Liang, using Landsat data from the U.S. Geological Survey.


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