Ice Sheets Today

The Greenland Ice Sheet had two extensive melt events in the second half of July. The second melt event had the seventh-largest melt area and fourth-highest runoff in the satellite record, which began in 1978.

Surface melt and total melt-day area for the Greenland Ice Sheet at the end of the 2021 spring season was below the 1981 to 2010 average.

With the exception of the northern and southern Antarctic Peninsula, the Antarctic melt season for 2020 to 2021 was unremarkable and below the 1990 to 2020 average.

With a correction applied, a first look at the 2020 to 2021 season points to an intense melt season in the northernmost and southernmost Antarctic Peninsula, but generally below-average melting elsewhere on the continent.

As the Southern Hemisphere enters into the full of swing of summer, parts of the Antarctic Ice Sheet are experiencing surface melting.

The 2020 melt season in Greenland is over, finishing thirteenth for cumulative melt-day extent in the 42-year satellite record. Melt extent was greater than any year prior to 2002, with about 70 percent of the ice sheet experiencing some melting.

Melting through the peak of Greenland’s summer melt season has been well above the 1981 to 2010 average, but below the levels of many previous summers of the past decade.

Spring melting over Greenland was near the long-term average, and concentrated along the southern coast, where extent was slightly above average.

Low winter snow cover, springtime heat waves, and a sunny summer led to a large runoff of meltwater from the Greenland ice sheet in 2019, primarily from its western side.

Warm air from Europe's heat wave reached Greenland on July 29 and 30, setting temperature records at Summit Station and melting about 90 percent of the ice sheet surface from July 30 to August 3. Melt runoff was estimated at 55 billion tons during the interval.

Between June 11 and 20, an extensive area of the Greenland Ice Sheet surface melted. At its peak on June 12, thawing climbed from the western and eastern coasts to elevations above 3,000 meters (9,800 feet).

Surface melting on the Northern Hemisphere’s largest mass of ice began during the second week of April, with several significant melting episodes at the end of the month and into early May.

Three major melt events during late July and August brought the 2018 Greenland melt season to a close. Overall, conditions on the ice sheet were slightly warmer than average for the second half of the summer.

May and June were markedly cooler than the average, although total melt-day area for the ice sheet is near average as of early July. Winds from the south and high air pressure over Iceland caused a spike in melt area in early July.

In 2017, the cumulative daily melt area for the Greenland Ice Sheet was the smallest since 1996, yet still higher than any year between 1979 and 1994 (1995 was a high melt season).

Surface melt spiked in mid-September in southern Greenland. A surge of warm air from the central Atlantic fueled the late melt event, which was confined to the southwestern and southeastern coasts and peaked on September 15, 2017.

Extensive and persistent melt in northern Greenland characterized late July to early August. A brief high pressure pattern centered on the west coast led to similar conditions that made 2015 a record melt year for the ice sheet's northern sections.

Despite moderately higher-than-average air temperatures and high air pressure over Greenland, the 2017 melt season began modestly. As of June 30, total melt area was the lowest since the 2009 melt season.

Melt extent in Greenland was above average in 2016, ranking tenth highest (tied with 2004) in the 38-year satellite record. Melt area in 2016 was slightly greater than in 2015, which ranked twelfth.

July 2016 had warm conditions and frequent melting in northern Greenland, similar to 2015 but not as extreme. However, last winter's low snowfall in the south meant that July's near-normal melting and slightly cool weather still produced above average melt water runoff, resulting in mass loss from the ice sheet.