Antarctica Today coming soon

Due to the data provider’s systems maintenance, data outage from the Defense Meteorological Satellite Program (DMSP) satellites is impacting the transition to Antarctica Today. Daily melt extent mapping for the Antarctic Ice Sheet will be restart when the issue is cleared. Mapping for the Greenland Ice Sheet is suspended for the winter. Calibration of yearly melt detection requires analysis of the springtime snow conditions by a separate program. See our March 18, 2013 post for more discussion of melt calibration. 

Our interactive chart supports a retrospective look at past Greenland melt seasons. This will remain available for our users.

Daily image updates will resume for the Greenland Ice Sheet in April 2023.

Record September

While most of the 2022 Greenland melt season was near average, September set records for high temperatures, melt extent, and ice loss. A persistent high air pressure pattern off the southeastern tip of the island, and low air pressure over the Canadian Archipelago—and remnants from Hurricane Fiona—drove the unusual conditions.

Overview of conditions

Figure 1a. The top left map illustrates cumulative melt days on the Greenland Ice Sheet for the 2022 melt season. The top right map illustrates the difference from the 1981 to 2010 average melt days for the same period. The bottom graph illustrates daily melt area for Greenland from April 1st through October 31st, 2022, with daily melt area for the preceding five years. The gray lines and bands depict the average daily melt area for 1981 to 2010, the interquartile range, and the interdecile range. ||Credit: National Snow and Ice Data Center/T. Mote, University of Georgia|High-resolution image

Figure 1a. The top left map illustrates cumulative melt days on the Greenland Ice Sheet for the 2022 melt season. The top right map illustrates the difference from the 1981 to 2010 average melt days for the same period. The bottom graph illustrates daily melt area for Greenland from April 1 through October 31, 2022, with daily melt area for the preceding five years. The gray lines and bands depict the average daily melt area for 1981 to 2010, the interquartile range, and the interdecile range.

Credit: National Snow and Ice Data Center/T. Mote, University of Georgia
High-resolution image

Cumulative daily melt area for the summer seasons over the 43-year satellite record. Average totals for the 1981-2010 30-year reference period, and for the most recent 21 years, 2001-2022 are shown as horizontal blue lines. ||Credit: National Snow and Ice Data Center/T. Mote, University of Georgia|High-resolution image

Figure 1b. This bar graph shows the daily cumulative melt area for the summer seasons over the 43-year satellite record. Average totals for the 1981 to 2010 30-year reference period, and for the most recent 21 years, 2001 to 2022 are shown as horizontal blue lines.

Credit: National Snow and Ice Data Center/T. Mote, University of Georgia
High-resolution image

For the melt season as a whole, ice sheet melting was well above average across the southwest and northeast while slightly below average in the northwest and southeast (Figure 1a). However, much of the above average seasonal melting resulted from an unusually warm September, particularly for the southwestern ice sheet. A major melting event took place at the beginning of September, with another significant melt spike in late September resulting from the remnants of Hurricane Fiona as an extra-tropical cyclone. Another period of above-average melt extent occurred in mid-July.

The 2022 melt season in Greenland overall (April 1 to October 31) had a cumulative total of 22.1 million square kilometers (8.53 million square miles) of melt, placing it at nineteenth highest in the 43-year satellite record (Figure 1b). While this is 18.1 million square kilometers (6.99 million square miles) above the 1981 to 2010 average, it is below the average for the twenty-first century years of 2001 to 2022 by 26.3 million square kilometers (10.2 million square miles). Though recent years have not reached or exceeded the extreme melting totals of 2010, 2012, or 2016, the past two decades continue to have consistently more melting than earlier years.

Conditions in context

Average Temperature and Height at 700 millibars

Figure 2. The top plot illustrates surface air temperatures as a difference from the 1990 to 2020 average for June 1 to to August 31, 2022, for Greenland and surrounding areas. The bottom plot shows the air pressure as indicated by the height difference from average of the 700 millibar level (about 10,000 feet above sea level) for Greenland and the surrounding region for the same period.

Credit: National Centers for Environmental Prediction (NCEP) Reanalysis data, National Center for Atmospheric Research
High-resolution image

Conditions for the core of the melt season from June to August, were not far from the long-term average, with slightly above average temperatures in the northern part of the ice sheet and its southern tip, but below average temperatures in its central area, especially the east-central coast (Figure 2). Low atmospheric pressure between Iceland and the eastern Greenland coast—a pattern termed the Icelandic Low—brought mostly westward-flowing winds in the north and cool winds from the northwest for the western and southern areas.

Record September

Figure 3. The map in the upper left shows the difference from average for melt days on the Greenland Ice Sheet for September in 2022, and shows the location of the Swiss Camp research station. At top right, automatic weather station air temperatures at Swiss Camp were above melting for much of September, 2022. The bottom plot illustrates the air pressure as indicated by the height difference from average of the 700 millibar level (about 10,000 feet above sea level) for Greenland and the surrounding region for the same period. Credits : National Centers for Environmental Prediction (NCEP) Reanalysis data, National Center for Atmospheric Research) and Swiss Camp data are from the GEUS GC-Net station, graphic by Jason Box, GEUS. High-resolution image

Figure 3a. The map in the upper left shows melt days as a difference from average on the Greenland Ice Sheet for September 2022, and shows the location of the Swiss Camp research station. The top right graph shows automatic weather station air temperatures at Swiss Camp, which were above melting for much of the month. The bottom plot illustrates the air pressure as indicated by the height difference from average of the 700 millibar level (about 10,000 feet above sea level) for Greenland and the surrounding region for the same period.

Credit: National Centers for Environmental Prediction (NCEP) Reanalysis data, National Center for Atmospheric Research; Swiss Camp data are from the Geological Survey of Denmark and Greenland (GEUS) Greenland Climate Network (GC-Net) station, graph by Jason Box, GEUS
High-resolution image

Figure 4. Meltwater runoff and total melt production per day for the Greenland Ice Sheet, June – September 2022, also showing 2020 and 2012 for comparison. Blue dashed line is the maximum daily value for any year between 1981 and 2010; in gray are the average amount and the typical range of values (standard deviation). These estimates are from the MAR 3.12 reanalysis model. Re Credit, Xavier Fettweis, University of Liége. Credits : National Centers for Environmental Prediction (NCEP) Reanalysis data, National Center for Atmospheric Research) and Jason Box, GEUS. High-resolution image

Figure 3b. These graphs show meltwater runoff at the top and total melt production at the bottom per day for the Greenland Ice Sheet from June to September 2022, along with 2020 and 2012. The blue dashed line represents the maximum daily value for any year between 1981 and 2010; in gray line and area depict the average amount and the typical range of values (standard deviation). These estimates are from the MAR 3.12 reanalysis model.

Credit: Xavier Fettweis, University of Liège
High-resolution image

September 2022 conditions were very different from earlier months, notably the June to August period (Figure 3a). A strong and persistent high air pressure pattern was present off of Greenland’s southeastern coast coupled with low air pressure in the Canadian Archipelago, resulting in a transfer of warm air from the southeast onto the ice sheet. This set record warm conditions and unprecedented surface melt extents through the month relative to the 40+ year satellite record. In most years, the September cumulative melt area totals do not exceed 1 million square kilometers (386,000 square miles). The 1981 to 2010 average is 486,000 square kilometers (188,000 square miles). By contrast, the 2022 cumulative melt area total was 3.9 million square kilometers (1.51 million square miles), more than doubling the previous record September melt. The record September prior to 2022 was 2010, with 1.6 million square kilometers (618,000 square miles).

Air temperatures for Greenland overall were 6 degrees Celsius (11 degrees Fahrenheit) above average at the 700 millibar level, roughly 10,000 feet above sea level. This is more than 3 standard deviations above the typical range, making it the warmest September on record since 1950 in the MAR 3.12 reanalysis record. Conditions at a weather station near Swiss Camp in Greenland show near-continuous melting conditions through the month, much warmer than the previous two years.

September 2022 had an unusual amount of melt and meltwater runoff (Figure 3b). The total amount of meltwater produced during the month was 57 billion tons, a record for September, compared to the 1981 to 2010 average September total of 9 billion tons—according to MARv3.12 forced by the ERA5 reanalysis. Runoff total was also a record at 55 billion tons. Total runoff in September was a high fraction of the total produced melt because warm events and rainfall occurred during the period of maximum bare ice exposure at the end of summer. Overall, the estimated total change in surface mass of the ice sheet surface (not considering the outflow of glaciers) was only -8 billion tons, a smaller number than melt and runoff because of the high amounts of rainfall that fell on the ice sheet (again a record for September since 1950), some of which freezes onto the snow or firn surface.

Exposed

Figure 5. Extent of exposed bare ice on the Greenland Ice sheet for 2022 and the preceding 5 years from Sentinel 3 data. Credit, Jason Box, GEUS, Adrien Wehrlé, Univ. of Zurich, and ESA EO Science For Society, ESA CCN 4000125043/18/I-NB.

Figure 4. This graph shows the extent of exposed bare ice on the Greenland Ice sheet for 2022 and the preceding five years from Sentinel 3 data.

Credit: Jason Box, Geological Survey of Denmark and Greenland (GEUS); Adrien Wehrlé, University of Zurich; and European Space Agency Earth Observation (ESA EO) Science For Society, ESA Contract Change Notice (CCN) 4000125043/18/I-NB
High-resolution image

The unusual timing of warm and rainy conditions throughout the month of September led to a jump in the amount of exposed bare ice on the ice sheet. In most years, snowfall begins to cover the icy edges of the ice sheet in September, but this year exposed bare ice increased to typical mid-summer levels. This has an effect on both melt, since darker bare ice absorbs more solar energy, and run-off, as the ice surface cannot absorb water.

Break-up of the last large ice shelf in Greenland

Figure 6. Landsat images spanning 22 years showing the retreat and breakup of the Zachariae Isstrøm ice shelf. Upper right, location of the ice shelf in northeastern Greenland. Christopher Shuman, NASA JCET/GSFC, and US Geological Survey.

Figure 5. These Landsat images span 22 years, showing the retreat and breakup of the Zachariae Isstrøm Ice Shelf. The upper right inset map shows the location of the ice shelf in northeastern Greenland. An animation by Christopher Shuman shows a longer series of images.

Credit: Christopher Shuman, University of Maryland, Baltimore Campus (UMBC) at NASA Goddard Space Flight Center (GSFC); data are from US Geological Survey
High-resolution image

Recently published research on the Zachariae Isstrøm (ZI) outlet glacier describes how this glacier’s floating ice shelf began to break apart early this century and is continuing to retreat under warming ocean and air conditions. As a result of the loss of the floating shelf, the grounded area of the glacier has accelerated and thinned, and it is now contributing more ice to the ocean.

Landsat data collected over the past 50 years indicates the floating ice in front of this outlet was relatively stable until late 2002. However, the loss of contact between the adjacent islands east of the ice shelf front initiated a break up in August 2002. This has proceeded with rapid ice front collapse events for the past several years.

References

Satellite Image Atlas of Glaciers of the World: Greenland

A melt spike in September?

As most of the western United States baked under a prolonged, record-setting heatwave at the beginning of September, Greenland also underwent a very unusual late-season melt event. Summit Station in Greenland, at an elevation of more than 3,200 meters (10,500 feet), surpassed the melting point for the first time on record in September on the afternoon of September 3. A strong high air pressure region parked at the southeastern edge of Greenland and drew warmer air northward along the western coast of Greenland and Baffin Bay beginning on September 2, leading to the melt event.

Overview of conditions

Figure 1. The top map shows the cumulative melt days for the 2018 melt season through July 7 (upper left) and the difference from the average (upper right) for May and June combined, referenced to the 1981 to 2010 period. Below is a plot of daily melt area for the 2018 season through July 7, compared with melt extents for 2017, 2016, and the 1981 to 2010 period. Data courtesy of Thomas Mote, University of Georgia. About the data Credit: National Snow and Ice Data Center/Thomas Mote, University of Georgia High-resolution image

Figure 1a. The top map shows the cumulative melt days for the 2022 melt season through September 5 (upper left) and the difference from the average (upper right) as referenced to the 1981 to 2010 period for the same time period. Below is a plot of daily melt area for the 2022 season through September 5. Data courtesy of Thomas Mote, University of Georgia. About the data

Credit: National Snow and Ice Data Center/Thomas Mote, University of Georgia
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Melt extent for September 2, 3, 4 and 5 showing the progression of the melt event across Greenland from passive microwave satellite observations. Credit: National Snow and Ice Data Center/T. Mote, University of Georgia High-resolution image

Figure 1b. These maps show the melt extent for September 2, 3, 4, and 5, illustrating the progression of the melt event across Greenland from passive microwave satellite observations. Data courtesy of Thomas Mote, University of Georgia. About the data

Credit: National Snow and Ice Data Center/Thomas Mote, University of Georgia
High-resolution image

Unprecedented in the 44 years of continuous satellite monitoring, a late season heat wave and melt event occurred in Greenland from September 2 to 5. At the peak on September 3, more than one-third (36 percent) of the ice sheet, or around 600,000 square kilometers (232,000 square miles) had surface melting (Figure 1a). The only comparable event so late in the season was in 2003, in late August (in terms of melt area) when temperatures at Summit reached only -2.5 degrees Celsius (27.5 degrees Fahrenheit). The melt event began along the southwestern coast on September 2, and moved rapidly inland and northward on September 3, accompanied by heavy rainfall that enhanced melt at lower elevations, and enhanced snowfall at higher elevations (Figure 1b).

To date this year, Greenland has had a near-average melt year overall, with the total melt-day area ranking twentieth in the 44-year record (Figure 1a). Melting is slightly above average in both northeastern and south-central Greenland, and slightly below average along the southeast coast and northwest.

Conditions in context

 Figure 2. The top plot illustrates average surface air pressure in millibars for the period September 1 to 3 for Greenland and the surrounding areas. The H indicates the center of the strong high air pressure cell that generated the northward winds along the western Greenland coast and Baffin Bay. The bottom plot shows wind direction (white streamlines) and surface temperature (color) for Greenland and the surrounding region on September 3 at mid-day.||Credit:National Centers for Environmental Prediction (NCEP) Reanalysis data, National Center for Atmospheric Research)|High-resolution image

Figure 2a. The top plot illustrates average surface air pressure in millibars for the period September 1 to 3 for Greenland and the surrounding areas. The H indicates the center of the strong high air pressure cell that generated the northward winds along the western Greenland coast and Baffin Bay. The bottom plot shows wind direction (white streamlines) and surface temperature (color) for Greenland and the surrounding region on September 3 at mid-day.

Credit: National Centers for Environmental Prediction (NCEP) Reanalysis data, National Center for Atmospheric Research
High-resolution image

Figure 4. Preliminary temperature, dew point, and air pressure record from NSF’s Summit Station in Greenland, posted by NOAA at www.xxx.xxx for September 2-5, 2022. Note that these data were not accessible for several hours early on September 4th. Data courtesy of the National Oceanic and Atmospheric Administration Global Monitoring Laboratory. Credit: National Centers for Environmental Prediction (NCEP) Reanalysis data, National Center for Atmospheric Research); and www.nullschool.net High-resolution image

Figure 2b. Preliminary temperature, dew point, and air pressure record from National Science Foundation’s Summit Station in Greenland, posted by the National Oceanic and Atmospheric Administration (NOAA) for September 2 to 5, 2022. Note that these data were not accessible for several hours early on September 4. Data courtesy of the National Oceanic and Atmospheric Administration Global Monitoring Laboratory.

Credit: Christopher A. Shuman, University of Maryland Baltimore County at NASA Goddard Space Flight Center
High-resolution image

Warm air moved rapidly northward from the central North Atlantic Ocean. A strong and relatively slow-moving high-pressure region and an atmospheric river—a relatively narrow band of high-moisture air—brought a considerable volume of snow and rain in the early days of the event (Figure 2a). This pulse of warm air then flowed eastward over the top of the ice sheet and descended onto the eastern edge, extending melting to the northern and eastern coast on September 4 and 5.

Temperatures at Summit Station were low in the early morning hours of September 2, but rose rapidly during that day. Increasing air pressure, which often accompanies melt events at Summit, began on September 3 and continued high through much of September 4. On September 3, several hours of above-freezing temperatures were recorded, reaching a peak of 0.4 degrees Celsius (32.7 degrees Fahrenheit) around 15:00 Greenwich Mean Time (GMT) on the third (Figure 2b). High temperatures on September 4 were slightly above -2 degrees Celsius (28.4 degrees Fahrenheit) and similarly warm conditions continued across the island until September 6.

The big runoff

This graph shows Greenland’s melt runoff (top graph) and the total melt in billions of tons (bottom graph) for each day since June 1 to July 25, for several time-periods. Melt runoff is the amount of meltwater that reaches the ocean; total melt amount is larger, because for some of the higher-elevation melting, the meltwater soaks into the snow and re-freezes. Credit: MARv3.12, X. Fettweis, University of Liège, Belgium High-resolution image

Figure 3. This graph shows Greenland’s melt runoff and the total melt in billions of tons from Jun 1 to September 5, 2022. Melt runoff is the amount of meltwater that reaches the ocean.

Credit: MARv3.14, Xavier Fettweis, University of Liège, Belgium
High-resolution image

Meltwater runoff, or the amount of surface water entering the ocean, from the Greenland Ice Sheet began increasing on September 2 at 5.6 billion tons per day, and peaked at just under 12 billion tons per day on the September 3. Data are from the Regional Atmosphere Model (MAR), which is a reanalysis model that uses Global Forecast System data from the National Centers for Environmental Prediction (NCEP). On September 4 and 5, runoff continued at 7.7 and 6.6 billion tons, respectively. The runoff total for September 3 was the highest of this melting season and is one of the 10 highest runoff days since 1950. However, this was moderated partially by heavy rainfall and snowfall on September 2 and 3, totaling 15.6 billion tons of input.

Such an intense melt and runoff event at this time of the year is exceptional as the energy coming from solar radiation is already very low at the beginning of September. Most of the record high runoff events have occurred in July, such as in 2012 and 2019.

This event has been followed by colder conditions, which caused refreezing of the melt at the top of the snowpack. This will lead to widespread formation of ice lenses within the snowpack. These shallow and impermeable ice lenses will reduce the capacity of the snowpack to retain meltwater next summer, tending instead to promote more widespread runoff and less local refreezing (MacFerrin et al., 2021).

Being there

Figure 4. Figure 6. Top, a picture from southern Greenland (north of Qagssimiut near the southern tip of the ice sheet) on September 2. Ominous skies with newly-defined Asperitus clouds indicative of intense weather. Bare dirty ice was present everywhere, and run-off and rain-driven flooding resumed after a late August hiatus. Bottom, wavy structure in the lower cloud deck indicative of asperitus clouds. Photos by Mette Hansgaard

Figure 4. The top photograph was taken in southern Greenland (north of Qagssimiut near the southern tip of the ice sheet) on September 2. Skies with newly-defined asperitas clouds are indicative of intense weather. Bare dirty ice was present everywhere, and runoff and rain-driven flooding resumed after a late August hiatus. The bottom photograph shows a wavy structure in the lower cloud deck indicative of asperitas clouds.

Credit: Mette Hansgaard
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A group of researchers camped near the ice edge in southern Greenland when the melt event began on September 2. The group observed intermittent rain, warm winds, and unusual wave-like clouds indicative of unstable conditions.

References

MacFerrin, M., H. Machguth, D. v. As et al. 2019. Rapid expansion of Greenland’s low-permeability ice slabs. Nature 573, 403–407. doi:10.1038/s41586-019-1550-3

Heat ripple

A moderate melt surge swept across northern Greenland and then encompassed much of the ice sheet perimeter in mid-July. Overall, the 2022 summer season in Greenland continues at a modest pace relative to the past few years (notably 2021 and 2019) as a result of neutral North Atlantic Oscillation (NAO) index conditions promoting frequent northern winds over Greenland but exceptional melt and southerly winds over Svalbard, the Norwegian-owned islands northeast of Greenland.

Overview of conditions

Figure 1. The top left map shows cumulative melt days on the Greenland Ice Sheet for the spring 2022 melt season. The top right map shows the difference from the 1981 to 2010 average melt days for the same period. The bottom graph shows daily melt area for Greenland from May 25 through August 6, 2022, with daily melt area for the preceding three years. The grey lines and bands depict the average daily melt area for 1981 to 2010, the inter-quartile range, and the interdecile range. ||Credit: National Snow and Ice Data Center/T. Mote, University of Georgia |High-resolution image

Figure 1. The top left map shows cumulative melt days on the Greenland Ice Sheet for the spring 2022 melt season. The top right map shows the difference from the 1981 to 2010 average melt days for the same period. The bottom graph illustrates daily melt area for Greenland from May 25 through August 6, 2022, with daily melt area for the preceding three years. The grey lines and bands depict the average daily melt area for 1981 to 2010, the inter-quartile range, and the interdecile range.

Credit: National Snow and Ice Data Center/T. Mote, University of Georgia
High-resolution image

As of July 25, 2022, the Greenland Ice Sheet seasonal melting cumulative extent (the sum of each day’s melt area since April 1) was 14.00 million square kilometers (5.41 million square miles), ranking it nineteenth highest in the 44-year satellite record. A slow start in April, May, and June preceded slightly above-average melt extents in July, culminating in a moderately extensive surge in melt across northern Greenland on July 15 to 18, and more widespread coastal melting in the days following through July 25. The events led to a brief period of relatively high meltwater run off, bringing the net snowfall and surface melt mass change to near the 1981 to 2010 average.

Melting from April 1 to July 25 has been slightly above the 1981 to 2010 mean along the southwestern coast, often the area with the greatest number of melt days, and above average across the northern ice sheet, the site of the first part of the recent surge in melt area. Areas of below-average melting along the southeast coast and parts of the northwest offset this. Overall, the melt day count is near-average for this date.

Conditions in context

Figure 2. The top plot shows average air temperature as a difference from the 1991 to 2020 average at the 700 millibar level, at about 3,000 meters (10,000 feet) above sea level, from June 20 to July 25, 2022. The bottom plot shows height of the 700-millibar pressure level as a difference from its average height over the same period.||Credit: National Centers for Environmental Prediction (NCEP) Reanalysis data, National Center for Atmospheric Research). |High-resolution image

Figure 2. The top plot shows average air temperature as a difference from the 1991 to 2020 average at the 700 millibar level, at about 3,000 meters (10,000 feet) above sea level, from June 20 to July 25, 2022. The bottom plot shows height of the 700-millibar pressure level as a difference from its average height over the same period.

Credit: National Centers for Environmental Prediction (NCEP) Reanalysis data, National Center for Atmospheric Research
High-resolution image

Air temperatures at the 700 millibar level (about 3,000 meters or 10,000 feet of elevation) for June 20 to July 25 were generally near-average, with somewhat warmer-than-average conditions along the northern and southern ends of the islands. Average temperatures were 2 degrees Celsius (4 degrees Fahrenheit) above average near Thule in northwest Greenland, and about 1 degree Celsius (2 degrees Fahrenheit) above average near Nuuk, the capital of Kalaalit Nunaat (the nation of Greenland). Near the National Science Foundation’s Summit Station, temperatures were near average through this period, although the station experienced several above average days during the more extensive melt events in the third week of July.

The pressure pattern (indicated by the height of the 700 millibar pressure level) shows a stronger-than-average low pressure area off the eastern coast of the island, and high pressure along the southern tip, which tended to drive warm winds across the southern tip and northward along Baffin Bay’s eastern coast. However, the pattern in the north favors more frequent, cooler, northerly or northeasterly winds, pushing this 2022 melt season towards average or below-average intensity.

Heat ripple

Figure 3a. This graph shows Greenland’s melt runoff (top graph) and the total melt in billions of tons (bottom graph) for each day since June 1 to July 25, for several time-periods. Melt runoff is the amount of meltwater that reaches the ocean; total melt amount is larger, because for some of the higher-elevation melting, the meltwater soaks into the snow and re-freezes. ||Credit: MARv3.12, X. Fettweis, University of Liège, Belgium |High-resolution image

Figure 3a. This graph shows Greenland’s melt runoff (top graph) and the total melt in billions of tons (bottom graph) for each day since June 1 to July 25, for several time-periods. Melt runoff is the amount of meltwater that reaches the ocean; total melt amount is larger, because for some of the higher-elevation melting, the meltwater soaks into the snow and re-freezes.

Credit: MARv3.12, X. Fettweis, University of Liège, Belgium
High-resolution image

Figure 3b. This plot shows preliminary air temperature, dew point, and air pressure readings from Summit, Greenland, for late July 21 through early July 24. ||Credit: XX |High-resolution image

Figure 3b. This plot shows preliminary air temperature, dew point, and air pressure readings from Summit, Greenland, for late July 21 through early July 24. Data courtesy of the National Oceanic and Atmospheric Administration Global Monitoring Laboratory.

Credit: Christopher A. Shuman, University of Maryland Baltimore County at NASA Goddard Space Flight Center
High-resolution image

Figure 3c. This animation shows temperature difference from average (in color, scale is in degrees Celsius) and winds (arrows on the plot) at the 700 mbar level, spanning July 10 to July 25, 2022. The animation shows the progression of two warm pulses of air: one coming up and over Scandinavia, leading to the melting seen on July 16 through 18 in far northern Greenland, and one moving up through Baffin Bay, initiating the second pulse of melting seen on July 20 through 24, with warm conditions reaching the Summit Station. Note the warm conditions over Svalbard on July 17th.||Credit: Xavier Fettweis, University of Liege, Belgium, and NOAA|High-resolution image

Figure 3c. This animation shows temperature difference from average (in color, scale is in degrees Celsius) and winds (arrows on the plot) at the 700 mbar level, spanning July 10 to July 25, 2022. The animation shows the progression of two warm pulses of air: one coming up and over Scandinavia, leading to the melting seen on July 16 through 18 in far northern Greenland, and one moving up through Baffin Bay, initiating the second pulse of melting seen on July 20 through 24, with warm conditions reaching the Summit Station. Note the warm conditions over Svalbard on July 17.

Credit: Xavier Fettweis, University of Liege, Belgium, and National Oceanic and Atmospheric Administration
High-resolution image

Beginning on July 15, a strong ridge of high pressure began to develop over Greenland, and warm air moving in from both the Canadian Arctic along West Greenland and from Svalbard to the east initiated an extensive melt event across northern Greenland after having generated the highest recorded melt volume over Svalbard on July 17.  Models of the initial event, spanning July 16 to 18, showed that meltwater runoff amounts increased to about 6 billion tons per day, or about 35 percent more than average at this time of summer (Figure 3a). As noted in media coverage, temperatures were near 15 degrees Celsius (about 60 degrees Fahrenheit) in the Thule area. Then in the following days, a pulse of warm air moved northward along the western coast, extending the melt area and intensity further, with melt runoff reaching 10 billion tons per day on July 22. During this second modest warm event, temperatures reached within 3 degrees Celsius (5 degrees Fahrenheit) of the melting point at Summit Station, about 8 degrees Celsius (14 degrees Fahrenheit) above average (Figure 3b). Melt extent and melt runoff returned to near-average levels after July 25.

An animation of air temperature differences from average and wind patterns (Figure 3c; click to animate) shows the progression of two warm pulses of air from July 10 to July 25: one northward over Scandinavia, promoting melting across northern Greenland seen on July 16 to 18, and one moving northward through Baffin Bay, initiating the second pulse of melting on July 20 to 24, with warm conditions reaching  Summit Station, central Greenland. Note the extremely warm conditions over Svalbard on July 17.

Greenland’s reflectivity

Figure 4a. This map shows the difference from average reflectivity, or average albedo, for the Greenland Ice Sheet from July 16 to 24, relative to the same period for the 2017 to 2021 average. Red areas in the north and northwest of the island indicate the extensive snow darkening or exposure of bare ice during the strong melt events of July. Areas along the southwestern coast in dark blue along the western coast indicate brighter than average snow conditions due to below-average melt. ||Credit: Jason Box, Geological Survey of Denmark and Greenland (GEUS) and Adrien Wehrlé, University of Zurich |High-resolution image

Figure 4a. This map shows the difference from average reflectivity, or average albedo, for the Greenland Ice Sheet from July 16 to 24, relative to the same period for the 2017 to 2021 average. Red areas in the north and northwest of the island indicate the extensive snow darkening or exposure of bare ice during the strong melt events of July. Areas along the southwestern coast in dark blue along the western coast indicate brighter than average snow conditions due to below-average melt.

Credit: Jason Box, Geological Survey of Denmark and Greenland (GEUS) and Adrien Wehrlé, University of Zurich
High-resolution image

Figure 4b. This chart illustrates the variation in reflectivity, not the difference from average, for northern Greenland as it varies with elevation for the periods before (July 5 to 9) and after the strong melt event in northern Greenland (July 15 to 19). ||Credit: Jason Box, Geological Survey of Denmark and Greenland (GEUS) and Adrien Wehrlé, University of Zurich. |High-resolution image

Figure 4b. This chart illustrates the variation in reflectivity, not the difference from average, for northern Greenland as it varies with elevation for the periods before (July 5 to 9) and after the strong melt event in northern Greenland (July 15 to 19).

Credit: Jason Box, Geological Survey of Denmark and Greenland (GEUS) and Adrien Wehrlé, University of Zurich
High-resolution image

Greenland’s snow and ice reflectivity, known as albedo, responds to warming events in several ways that all tend to make the surface darker, and therefore more absorbing of solar energy, which is abundant across northern Greenland at this time of year. During the mid-July melt event in northern Greenland the northern portion of the ice sheet reflected 5 to 10 percent less sunlight as a result of coarsening snow grains, wet conditions in the snow, or greater exposure of darker bare ice (Figure 4a). These factors mean that ice sheets under warming climate conditions undergo an amplification of absorbing energy as the snow warms and melts because of high amounts of sunlight, darkening snow and ice surfaces, and meltwater running off the ice sheet.

Greenland’s reflectivity can now be tracked on a daily basis (if clouds permit) at a resolution of 300 meters (about 1,000 feet) using the European Space Agency’s Sentinel-3 satellite’s Ocean and Land Color Instrument (Figure 4b). This product is now available from the Geological Survey of Denmark and Greenland (GEUS). Albedo controls the amount of solar energy that the snow and ice surface absorbs during daylight hours, and is strongly influenced by the buildup of dust, soot, and ice algae on the surface.

Severe summer in Svalbard

Figure 7. The top plot shows net gain or loss of ice for the glaciers and ice caps of Svalbard (also known as Spitzbergen) for the current hydrologic year through July 25. The bottom figure shows surface air temperature difference from average for May 1 to July 25, 2022, for the far northern Atlantic and the Svalbard region. ||Credit: X. Fettweis and MAR 3.12, University of Liege, Belgium; and NOAA NCEP |High-resolution image

Figure 5. The top plot shows net gain or loss of ice for the glaciers and ice caps of Svalbard (also known as Spitzbergen) for the current hydrologic year through July 25. The bottom figure shows surface air temperature difference from average for May 1 to July 25, 2022, for the far northern Atlantic and the Svalbard region.

Credit: X. Fettweis and MAR 3.12, University of Liege, Belgium; and the National Oceanic and Atmospheric Administration National Centers for Environmental Prediction
High-resolution image

The current cumulated melt over Svalbard, from June 1 to July 31, is 1.5 times larger than the previous record from 2018, an event having a 1 in 3.5 million chance (a ‘5 sigma deviation from the mean’) if climate were completely random. However, under the current global warming trend driven by heat-trapping gases, these astronomical odds are much lower. The causes of the extreme summer are linked to several recent events. Winter snowfall was low, allowing older, darker snow or old, bare ice to make an earlier appearance during the melt season. The sea ice moved north of the archipelago at the end of spring, something that does not always happen even by late summer. This exposed the ocean during the peak sunshine period, and allowed warm air to reach the islands without flowing over a frozen ocean surface first. Ocean conditions are also very warm near Svalbard as a result. Lastly, the wind and air pressure patterns have been very persistent for the region this summer, setting up persistent southerly warm winds reaching the archipelago but bringing northern winds to Greenland frequently, explaining why melt is close to average over Greenland and exceptional over Svalbard.

Spring chillin’ in Greenland; Antarctica’s summer summary

Seasonal surface melting in Greenland got off to a slow start in 2022. Persistent winds from the northwest across the melt-prone areas of the western coastal ice sheet have kept the total number of melt days well below average. Snowfall through last winter was slightly higher than average. In Antarctica, several areas had an intense coastal surface melting pulse at the end of the summer, in part associated with the extreme atmospheric river landfall event in mid-March.

Overview of conditions

Figure 1. Top left, cumulative melt days map of Greenland for the Spring 2022 melt season. Top right, map of the difference from the 1981-2010 average melt days for the same period. Bottom, daily melt area for Greenland from April 1st through June 20th, 2022, with daily melt area for the preceding five years. In gray are the mean daily melt area for 1981-2010, the inter-quartile range, and the interdecile range.

Figure 1. The top left map shows cumulative melt days on the Greenland Ice Sheet for the spring 2022 melt season. The top right map shows the difference from the 1981 to 2010 average melt days for the same period. The bottom graph shows daily melt area for Greenland from April 1 through June 20, 2022, with daily melt area for the preceding five years. The grey depicts the average daily melt area for 1981 to 2010, the inter-quartile range, and the interdecile range.

Credit: National Snow and Ice Data Center/T. Mote, University of Georgia
High-resolution image

Through June 20, 2022, the Greenland Ice Sheet had the lowest spring surface melt in the past decade. The total aerial extent of surface melting was just over 2.27 million square kilometers (876,000 million square miles), well below the 1981 to 2010 average of 3.72 million square kilometers (1.44 million square miles). Melting was below average along the western edge of the ice sheet (10 to 15 days behind the average rate) and near-average along the southeastern coast where melting occurred primarily at low elevations. A small area of the southern tip of the island had slightly above average melting.

Conditions in context

Figure 2. Top, average air temperature difference from the 1981-2010 average at the 700 mb level, or about 10,000 feet above sea level, for the period May 1st through June 20th; bottom, height difference from average for the 700mb pressure level in the atmosphere for the same period.||Credit: National Centers for Environmental Prediction (NCEP) Reanalysis data, National Center for Atmospheric Research).

Figure 2a. The top plot shows average air temperature as a difference from the 1981 2010 average at the 700 millibar level, or about 3,000 meters or 10,000 feet above sea level, from May 1 to June 20, 2022. The bottom plot shows height at the 700 millibars as a difference from average.

Credit: National Centers for Environmental Prediction (NCEP) Reanalysis data, National Center for Atmospheric Research).
High-resolution image

Figure 3. Surface mass balance for Greenland (SMB, the sum of snowfall and rainfall minus evaporation or runoff) relative to a 1981-2010 reference period for the autumn-winter-spring season for 2021-2022 (red line) through June 26th (based on forecast as well as re-analysis) and for several full-season comparison years in the record. The estimates come from a regional climate model forced by the ERA5 Reanalysis data and the GFS forecast based on daily weather measurements and projections. || Credit: MARv3.12, X. Fettweis, University of Liège, Belgium|High-resolution image

Figure 2b. This graph shows surface mass balance (SMB), which is the sum of all precipitation minus evaporation or runoff, for Greenland Ice Sheet relative to the 1981 to 2010 reference period. The red line depicts SMB from fall 2021 to spring 2022 through June 26 based on forecast and re-analysis. For comparison, several full-season years are shown. The estimates come from a regional climate model forced by the ERA5 Reanalysis data and the Global Forecast System (GFS) forecast based on daily weather measurements and projections.

Credit: MARv3.12, X. Fettweis, University of Liège, Belgium
High-resolution image

Air temperatures at the 700 millibar level (about 3,000 meters or 10,000 feet elevation) for May and June through June 20 were generally below average by about 1.5 degrees Celsius (3 degrees Fahrenheit) (Figure 2a). A small area of the southern tip of the island had slightly warmer-than average conditions. Near the National Science Foundation’s Summit Station, temperatures were about 2 degrees Celsius (4 degrees Fahrenheit) below average. The difference from average height of the 700 millibar pressure level is used to determine air pressure patterns over Greenland. The height indicates below average pressure off the southeastern coast extending to Iceland and relatively strong high pressure over Baffin Island and Labrador. This pattern drives winds from the northwest down across the western coast of Greenland, keeping conditions cooler than average there.

As noted above, total snowfall for the Greenland Ice Sheet in the 2021-2022 autumn-winter-spring period has been slightly greater than average by about 6 percent (Figure 2b). Areas of higher snowfall include the western coast and broad areas of the northern and eastern ice sheet, although in general the excess was small. A few areas at the southern tip and the southeastern coast had below average snow accumulation this season.

Greenland’s reflectivity

Figure 4. (a) Average Albedo, or net reflectivity, for the Greenland Ice Sheet for the 30 day period June 20th, 2022 relative to the same period for 2017-2022. Pink and reddish areas in the south and southwest indicate darker-than-average (relative to the preceding five years); dark blue band along the western coast indicate brighter than average snow conditions, due to below-average melt. ||Credit: Jason Box, Geological Survey of Denmark and Greenland (GEUS)|High-resolution image

Figure 3. This map shows the average reflectivity, also known as albedo, for the Greenland Ice Sheet, for the 30-day period up to June 20, 2022, relative to the same period for 2017 to 2022. Pink and reddish areas in the south and southwest indicate darker-than-average (relative to the preceding five years); dark blue band along the western coast indicates brighter than average snow conditions from below-average melt.

Credit: Jason Box, Geological Survey of Denmark and Greenland (GEUS)
High-resolution image

Greenland’s snow and ice reflectivity, known as albedo, can be tracked on a daily basis at a resolution of 300 meters (about 1,000 feet) using the European Space Agency’s Sentinel-3 satellite’s Ocean and Land Colour Instrument. This product is now available from the Geological Survey of Denmark and Greenland (GEUS). The map for June 20 shows a slightly darker surface over a broad region of the ice sheet, with narrow zones near the southern coast where some above average melting occurred. Most of the central western ice edge and southwest ice edge (ablation areas of the ice sheet) is considerably brighter than average because white snow covers the darker ice below late in to the spring season. This is usually the region with the darkest surface and greatest amount of bare ice in years with a strong early melt season.

Late summer melting in Antarctica

Figure 4a. The top map shows the total melt days for the Antarctic Ice Sheet from November 1, 2021, to April 30, 2022. The middle map shows Antarctica’s melt days as a difference from average relative to a 1990 to 2020 reference period. The bottom graph shows daily melt extent as a percent of the ice sheet for the 2021 to 2022 season through February 13, and the average values and ranges for the reference period. Credit: L. Lopez, NSIDC, M. MacFerrin, CIRES and T. Mote, University of Georgia|High-resolution image

Figure 4a. The upper left map shows the total melt days for the Antarctic Ice Sheet from November 1, 2021, to April 30, 2022. The upper right map shows Antarctica’s melt days as a difference from average relative to a 1990 to 2020 reference period. The bottom graph shows daily melt extent as a percent of the ice sheet for the 2021 to 2022 season through February 13, and the average values and ranges for the reference period.

Credit: L. Lopez, National Snow and Ice Data Center, M. MacFerrin, Cooperative Institute for Research in Environmental Sciences, and T. Mote, University of Georgia
High-resolution image

Figure 4b. These graphs show daily melt extent for two regions with late summer melt events. Both the Amundsen-Bellingshausen region and the Wilkes-Adelie Land region had significant melt events in March 2022. ||Credit: L. Lopez, NSIDC, M. MacFerrin, CIRES and T. Mote, University of Georgia|High-resolution image

Figure 4b. These graphs show daily melt extent for two regions with late summer melt events. Both the Amundsen-Bellingshausen region and the Wilkes-Adelie Land region had significant melt events in March 2022.

Credit: L. Lopez, National Snow and Ice Data Center, M. MacFerrin, Cooperative Institute for Research in Environmental Sciences, and T. Mote, University of Georgia
High-resolution image

Final maps and charts for the 2021 to 2022 melt season in Antarctica look very similar to the melt totals shown in our previous late February post, but two late-season melt events are noteworthy (Figure 4a). Around March 2 to 3, a strong melt event took place along the Amundsen Coast, including some of the Pine Island and Abbott Ice Shelf areas (Figure 4b). Then in mid-March, a powerful atmospheric river event pushed warm air and moisture onto the Wilkes Land coast and far up onto the East Antarctic Plateau, bringing extended melt conditions to the coast and astounding high temperature records to several high-elevation stations well inland. Both Dome Concordia, the European Antarctic Plateau research station, and Vostok Station, the Russian base at 3,500 meters (11,500 feet) elevation, shattered records for March high temperatures by ten or more degrees Celsius (over 18 degrees Fahrenheit). Overall, however, Antarctic melting remained near-average for the year, with only the Larsen Ice Shelf region and the Rio Baudoin Ice Shelf showing strong melting above the long-term average. Despite the late event, the Abbott Ice Shelf was one of the below-average melt areas, as was the Ross Embayment region with near-zero melting for the summer.

High snowfall in Antarctica for 2021 and 2022

Figure 7. Antarctica’s snowfall (surface mass balance) for the 2021-2022 hydrologic year and two recent years, differenced from the average trend (horizontal grey line) and the range for 90% of the years on record (grey band), from a climate model (MAR 3.12, based on ERA5 weather re-analysis data; ||Credit: X. Fettweis, University of Liège|High-resolution image

Figure 5. This graph shows Antarctica’s snowfall as a difference from average (horizontal grey line) for the 2021- 2022 hydrologic year and two recent years. The grey band indicates the range for 90 percent of the years on record from the MARv3.12 climate model based on ERA5 weather re-analysis data.

Credit: X. Fettweis, University of Liège, Belgium
High-resolution image

Above average snowfall for the past two years over the southern continent may equal or exceed the amount of ice loss from excess outflow from the glaciers and seasonal melting. Snowfall has been increasing over some coastal areas of Antarctica in recent years, but 2021 and 2022 had unusually high snow input. Increased airflow from the north to both Queen Maud Land and Wilkes Land increased warm moist air, resulting in high snowfall. The increased airflow over Wilkes Land also resulted in unusually warm conditions at the South Pole in recent decades (Clem et al., 2021). High snowfall has also been linked to the record low sea ice extent surrounding Antarctica because a lack of sea ice increases humidity.

References

Box, J. E., A. Wehrlé, D. van As, R. S. Fausto, K. K. Kjeldsen, A. Dachauer, A., et al. 2022Greenland ice sheet rainfall, heat and albedo feedback impacts from the mid-August 2021 atmospheric River. Geophysical Research Letters, e2021GL097356, https://doi.org/10.1029/2021GL097356

Clem, K. R., R. L. Fogt, J. Turner, B. R. Lintner, G. J. Marshall, J. R. Miller, and J. A. Renwick. 2020. Record warming at the South Pole during the past three decades. Nature Climate Change, 10(8), 762-770, https://doi.org/10.1038/s41558-020-0815-z

Mankoff, K. D., X. Fettweis, P. L Langen, M. Stendel, K. K. Kjeldsen, N. B. Karlsson, B. Noël, M. R. van den Broeke, A. Solgaard, W. Colgan, J. E. Box, S. B. Simonsen, M. D. King, A. P. Ahlstrøm, S. B.  Andersen, and R. S. Fausto. 2021. Greenland ice sheet mass balance from 1840 through next week. Earth System Science Data, 13, 5001–5025, https://doi.org/10.5194/essd-13-5001-2021

Daily updates return for Greenland Today, end for Antarctica Today

Daily melt extent mapping for Greenland Ice Sheet has resumed, while mapping for the Antarctic Ice Sheet has suspended for its winter season. Calibration of yearly melt detection requires analysis of the springtime snow conditions by a separate program. See our March 18, 2013 post for more discussion of melt calibration. A full analysis for the 2021-2022 melt season on the Antarctic Ice Sheet will be coming soon.

Daily image updates will resume for the Antarctic Ice sheet in October 2022.

Late season melt events, Larsen fast ice breakout

As a whole, surface melting on the Antarctic Ice Sheet has been near average. After a series of warm events followed by intense down-slope winds, the eastern side of the Antarctic Peninsula sustained widespread melting and loss of decade-old fast ice in the Larsen B embayment. The Peninsula also experienced a strong late-season melt event that covered much of the western side.

Current conditions

Figure 1a. The top map shows the total melt days for the Antarctic Ice Sheet from November 1, 2021, to February 13, 2022; The middle map shows the difference from average relative to 1990 to 2020 reference period. The bottom graph shows daily melt extent as a percent of the ice cap for the 2021 to 2022 season through February 13, and the average values and ranges for the reference period. ||Credit: L. Lopez, NSIDC, M. MacFerrin, CIRES and T. Mote, University of Georgia|High-resolution image

Figure 1a. The top map shows the total melt days for the Antarctic Ice Sheet from November 1, 2021, to February 13, 2022; The middle map shows Antarctica melt days as a difference from average relative to 1990 to 2020 reference period. The bottom graph shows daily melt extent as a percent of the ice sheet for the 2021 to 2022 season through February 13, and the average values and ranges for the reference period.

Credit: L. Lopez, NSIDC, M. MacFerrin, CIRES and T. Mote, University of Georgia
High-resolution image

Figure 1b. These graphs show regional daily melt extent for seven Antarctic regions. As shown in Figure 1, surface melting is limited to near-coastal areas everywhere except the Antarctic Peninsula this year. ||Credit: L. Lopez, NSIDC, M. MacFerrin, CIRES and T. Mote, University of Georgia|High-resolution image

Figure 1b. These graphs show regional daily melt extent for seven Antarctic regions. As shown in Figure 1a, surface melting is limited to near-coastal areas everywhere except the Antarctic Peninsula this year.

Credit: L. Lopez, NSIDC, M. MacFerrin, CIRES and T. Mote, University of Georgia
High-resolution image

Antarctic surface melting through February 13 has been near average for the continent as a whole relative to the 1991 to 2020 reference period. (The NSIDC science team will now be using this new 30-year reference period for Antarctica Today and Greenland Today). The number of surface melt days was above average over most of the Antarctic Peninsula and over the Dronning Maud Land and Enderby Land region, but below average in the Amery Ice Shelf and Amundsen-Bellingshausen regions (Figures 1a and 1b). In the Maud and Enderby region, melting was particularly frequent on the Roi Baudouin Ice Shelf, an area prone to widespread melt flooding, although only a few melt ponds appeared this year. Other isolated areas of coastal East Antarctica also had above average melting, such as the West and Shackleton Ice Shelves. The Ross and Ronne Ice Shelves and the Wilkes and Adelie region had only small regions of surface melting.

Conditions in context

Figure 2a. This plot shows the departure from average air temperature over Antarctica at the 925 hPa level, in degrees Celsius, from January 1 to February 15, 2022. Yellows and reds indicate higher than average temperatures; blues and purples indicate lower than average temperatures. ||Credit: NSIDC courtesy NOAA Earth System Research Laboratory Physical Sciences Laboratory|High-resolution image

Figure 2a. This plot shows the departure from average air temperature over Antarctica at the 925 hPa level, in degrees Celsius, from January 1 to February 15, 2022. Yellows and reds indicate higher than average temperatures; blues and purples indicate lower than average temperatures.

Credit: NSIDC courtesy NOAA Earth System Research Laboratory Physical Sciences Laboratory
High-resolution image

Figure 2b. This plot shows the departure from average sea level pressure in the Antarctic at the 925 hPa level, in degrees Celsius, from January 1 to February 15, 2022. Yellows and reds indicate higher than average air pressures; blues and purples indicate lower than average air pressures. ||Credit: NSIDC courtesy NOAA Earth System Research Laboratory Physical Sciences Laboratory|High-resolution image

Figure 2b. This plot shows the departure from average sea level pressure in the Antarctic in millibars from January 1 to February 15, 2022. Yellows and reds indicate higher than average air pressures; blues and purples indicate lower than average air pressures.

Credit: NSIDC courtesy NOAA Earth System Research Laboratory Physical Sciences Laboratory
High-resolution image

Figure 2c. This plot shows average sea level pressure for the Antarctic Peninsula from February 6 to 10, 2022. During this period, an intense foehn event was observed along the eastern Peninsula. ||Credit: National Centers for Environmental Prediction (NCEP) Reanalysis data, National Center for Atmospheric Research|High-resolution image

Figure 2c. This plot shows average sea level pressure for the Antarctic Peninsula from February 6 to 10, 2022. During this period, an intense foehn event, where dry and warm winds cascade on the downwind side of a mountain, was observed along the eastern Peninsula.

Credit: National Centers for Environmental Prediction (NCEP) Reanalysis data, National Center for Atmospheric Research
High-resolution image

Antarctic climate conditions for the second half of the melt season this year, January 1 to February 15 (Figures 2a and 2b), have been driven primarily by a strong Amundsen Sea Low that is positioned westward of its usual location. This location, and the presence of a more northerly high pressure area northeast of it, have produced strong winds from the northwest across the Peninsula, as manifested by the frequent foehn events, where dry, warm, down-slope winds occur on the downwind side of a mountain range, that have been observed there. These are warm high-wind days for the eastern Peninsula that lead to extensive melting. However, despite the frequent warm gusts in the Peninsula, that area and most of the coastal regions have seen near-average temperatures over the period, while much of the interior of the continent has been warmer than average (Figure 2a). Wilkes Land and the regions near Shackleton Ice Shelf and West Ice Shelf are cooler than the norm.

The weather that caused the intense melt event on the Peninsula in early February was an example of the foehn wind events. The pattern of sea level pressure for February 6 to 10 shows high pressure the Scotia Sea and far southern Atlantic, and low pressure over the Amundsen Sea, producing intense winds from the north and northwest (Figure 2c). As these reach the Peninsula, they typically cause high rates of snowfall on the western side of the Peninsula ridge, and strong, warm downsloping foehn winds on the eastern side. More than 50 percent of the Peninsula’s ice cover melted during this period.

 

Antarctica’s snow input surges since November

Figure 3. The top plot shows trends in total mass input as snow and rain minus small amounts removed by evaporation for Antarctica from March 1, 2021 to February 24, 2022 relative to the average for the same period for 1981 to 2010. The previous four years are also shown for comparison, as well as the range of variability (standard deviation) for the 30-year reference period. ||Credit Xavier Fettweis, MAR 3.11 model, climato.be website. |High-resolution image

Figure 3. The top plot shows trends in total mass input as snow and rain minus small amounts removed by evaporation for Antarctica from March 1, 2021 to February 24, 2022 relative to the average for the same period for 1981 to 2010. The previous four years are also shown for comparison, as well as the range of variability (standard deviation) for the 30-year reference period.

Credit Xavier Fettweis, MAR 3.11 model, climato.be website.
High-resolution image

Models of Antarctica’s climate, guided by actual weather data in a reanalysis, indicate that higher-than-average snowfall in the western and southern Peninsula and Queen Maud Land have pushed the net total mass of precipitation upward steeply since November (Figure 3). This pattern is a result of the strong Amundsen Sea Low through the late 2021 to early 2022 period, and a series of storms in the eastern Weddell Sea and Queen Maud Land coastal area. Much of the western and southwestern coast of the Antarctic Peninsula has seen more than 50 centimeters (20 inches) more water, in the form of snow, than the 1981 to 2010 average. Queen Maud Land coastal areas have seen up to 25 centimeters (10 inches) more water as snow. However, much of the coastal area facing the Amundsen Sea, from Pine Island Bay to the Ross Ice Shelf, and the interior Ross Ice Shelf and Siple Coast areas saw considerably less net snow input than average, again as a consequence of the stronger-than-average Amundsen Sea Low.

Larsen B fast ice breaks out

Figure 3a to 3d. These images show break-out of landfast ice from the Larsen A and Larsen B embayments in the 2021 to 2022 summer season. Each image is 200 km (120 miles) across; north is to the upper left. The fast ice was stable through late November (image a), but extensive melting and strong northwesterly winds caused extensive surface melting (blue tint in image b). In mid-January, the Larsen B fast ice began to fracture (image c), and by mid-February, glacier mélange areas began to break-up and spread into the embayment (image d). ||Credit: XX|High-resolution image

Figures 4a to 4d. These images show break-out of landfast ice, a continuous sheet of frozen ocean that is bound to the coast, from the Larsen A and Larsen B embayments in the 2021 to 2022 summer season. Each image is 200 km (120 miles) across; north is to the upper left. The fast ice was stable through late November (image a), but extensive melting and strong northwesterly winds caused extensive surface melting (blue tint in image b). In mid-January, the Larsen B fast ice began to fracture (image c), and by mid-February, glacier mélange areas began to break-up and spread into the embayment (image d).

Credit: Christopher A. Schuman, University of Maryland Baltimore County and the NASA Earth Observing System Data and Information System Worldview
High-resolution image

Figure 3e. This image, looking westward into the Jorum Glacier fjord, was taken during a flight over the Larsen B embayment by British Antarctic Survey pilots on January 31, 2022, after fast ice in the Larsen B embayment broke out. ||Credit: British Antarctic Survey|High-resolution image

Figure 4e. This image, looking westward into the Jorum Glacier fjord, was taken during a flight over the Larsen B embayment by British Antarctic Survey pilots on January 31, 2022, after fast ice in the Larsen B embayment broke out.

Credit: British Antarctic Survey
High-resolution image

The Antarctic Peninsula has had an active melt season. Following intense melting in December, January experienced a lull in strong melt events. Surface melting produced extensive melt ponds through December and January along the fast ice and lower glacier fronts in the northeastern Peninsula, the sites of the former Larsen A and Larsen B Ice Shelves. Since their disintegrations in 1995 and 2002, respectively, landfast sea ice has formed in the area of the former shelves. Landfast sea ice, or “fast ice,” is a continuous sheet of frozen ocean that is bound to the coast and “holds fast” to the shoreline. For the Larsen A, this fast ice has broken out nearly every summer. By contrast, fast ice that formed in the Larsen B embayment in early 2011 has remained there continuously. On December 8, 2021, the seasonal fast ice broke up in the Larsen A embayment, and the embayment was nearly ice-free by the end of that month. On January 17 to 19, 2022, fast ice in the Larsen B embayment began to break out, and by January 21, the ice was fractured throughout its extent (Figures 4a to 4c).

Landfast ice has been shown to have a stabilizing effect on ice shelves and glaciers. After the Larsen B Ice Shelf collapsed in 2002, glaciers that once flowed into the ice shelf retreated. However, over the 11-year period of fast ice presence, glaciers have partially re-advanced, protected by the fast ice in the bay. With the break-out of the fast ice, these glacier tongues and mélange areas are now retreating and collapsing, causing a second spread of broken floating ice pieces to emerge from the Larsen B coast (Figure 4d).

On January 31, pilots from the British Antarctic Survey flew to the area of the Larsen B embayment and took several pictures of the ice front areas and the mélange. Several areas have large bergs and broken glacier ice emerging from the fjords (Figure 4e).

Further reading

Barrand, N. E., D. G. Vaughan, N. Steiner, M. Tedesco, P. Kuipers Munneke, M. R. van den Broeke, and J. S. Hosking. 2013. Trends in Antarctic Peninsula surface melting conditions from observations and regional climate modeling. Journal of Geophysical Research: Earth Surface, 118(1), pp.315-330. Doi:10.1029/2012JF002559.

Fraser, A. D., R. A. Massom, M. S. Handcock, P. Reid, K. I. Ohshima, M. N.  Raphael, J. Cartwright, A. R. Klekociuk, Z. Wang, and R. Porter-Smith. 2021. Eighteen-year record of circum-Antarctic landfast-sea-ice distribution allows detailed baseline characterisation and reveals trends and variability. The Cryosphere, 15(11), pp.5061-5077. doi: 10.5194/tc-15-5061-2021.

Gomez‐Fell, R., W. Rack, H. Purdie, and O. Marsh. 2022. Parker Ice Tongue Collapse, Antarctica, Triggered by Loss of Stabilizing Land‐Fast Sea Ice. Geophysical Research Letters, 49(1), p.e2021GL096156. doi:10.1029/2021GL096156.

Massom, R. A., A. B. Giles, H. A. Fricker, R. C. Warner, B. Legrésy, G. Hyland, et al. 2010. Examining the interaction between multi-year landfast sea ice and the Mertz Glacier Tongue, East Antarctica: Another factor in ice sheet stability? Journal of Geophysical Research: Oceans, 115(12), 1–15. doi:10.1029/2009JC006083.

Antarctica Today: melt season underway

As the Greenland Ice Sheet endures winter in the Northern Hemisphere, we take a break from Greenland and move to the south where summer reigns over the Antarctic Ice Sheet in the Southern Hemisphere. Here we track the melt extent over Antarctica, adapting the same basic method as is used for Greenland. So far during the austral spring and summer, except for the northern part of the Antarctic Peninsula and in the area of the Roi Baudion Ice Shelf, few areas on the Antarctic Ice Sheet had any significant surface melting as of this post. 

Overview of conditions

Figure 1a. The top map shows the total melt days for the Antarctic Ice Sheet from November 1, 2021 to December 31, 2021. The bottom graph shows daily melt extent as a percent of the ice sheet through December 26, 2021, and the average values and ranges for the reference period.||Credit: M. MacFerrin, CIRES and T. Mote, University of Georgia|High-resolution image

Figure 1a. The top map shows the total melt days for the Antarctic Ice Sheet from November 1, 2021, to January 9, 2022. The bottom graph shows daily melt extent as a percent of the ice sheet through January 9, 2022, and the average values and ranges for the reference period.

Credit: L. Lopez, NSIDC, M. MacFerrin, CIRES and T. Mote, University of Georgia
High-resolution image

Figure 1c: departure from average air temperature over Antarctica.||Credit: NSIDC courtesy NOAA Earth System Research Laboratory Physical Sciences Laboratory| High-resolution image

Figure 1b. This plot shows the departure from average air temperature over Antarctica at the 925 hPa level, in degrees Celsius, from November 1 to December 31, 2021. Yellows and reds indicate higher than average temperatures; blues and purples indicate lower than average temperatures.

Credit: NSIDC courtesy NOAA Earth System Research Laboratory Physical Sciences Laboratory
High-resolution image

Figure 1c.

Figure 1c. This map of the Antarctic Ice Sheet shows melt days from November 1, 2021, to January 9, 2022, as a difference from average relative to the 1990 to 2020 reference period. Reds indicate areas of more melt; blues indicate areas of less melt.

Credit: L. Lopez, NSIDC, M. MacFerrin, CIRES and T. Mote, University of Georgia
High-resolution image

The most significant surface melting as of this post occurred in the northern part of the Antarctic Peninsula (Figure 1a). Strong, warm winds flowed east and downslope on the eastern side of the northern Antarctic Peninsula, causing melting. A strong Amundsen Sea low and a high positive Southern Annular Mode (SAM) pattern brought snow and windy conditions to the southwestern side of the Peninsula.

While the interior of the East Antarctic Ice Sheet was quite warm during November and December relative to the reference period, this region typically does not approach the melting temperature (Figure 1b). Coastal areas of the continent, however, had average to above average surface melting. Cool conditions have limited the number of melt days across the Amery Ice Shelf (Figure 1c).

Conditions in context

Figure 2a. The bottom graph shows the daily total melt as a percent of the total ice area of the region through December 26, 2021, and the average values and ranges for the 1990 to 2020 reference period. ||Credit: M. MacFerrin, CIRES and T. Mote, University of Georgia|High-resolution image

Figure 2a. This graph shows the daily total melt as a percent of the total ice area of the region through January, 2022, and the average values and ranges for the 1990 to 2020 reference period.

Credit: L. Lopez, NSIDC, M. MacFerrin, CIRES and T. Mote, University of Georgia
High-resolution image

image of the northern Antarctic Peninsula acquired on 21st December 2001 by NASA’s Terra satellite; inset, zoom image of the Larsen B embayment and remnant ice shelf at SCAR Inlet

Figure 2b. This close-up image of the Antarctic Peninsula shows the Larsen B embayment with deep meltwater fractures. Larsen B lies north of the remnant ice shelf at the Scientific Committee on Antarctic Research (SCAR) Inlet. This image was acquired from the Moderate Resolution Imaging Spectroradiometer (MODIS) instrument on the NASA Terra satellite on December 21, 2021.

Credit: NASA WorldView
High-resolution image

One of the few regions with significant surface melting on the Antarctic Ice Sheet is the northern Antarctic Peninsula, where a series of windstorms has resulted in several brief early-season melt events (Figure 2a). Seasonal landfast sea ice filling the Larsen A embayment broke apart and began to drift northward on December 8. Multiyear fast ice in the Larsen B embayment, in place continuously since early 2011, now has widespread meltwater flooding with some deeper ponds and some areas drained by narrow fractures (curved whiter streaks). The outer fringe of this fast ice also broke out on December 8. South of the Larsen B embayment, the remnant ice shelf known as Scientific Committee on Antarctic Research (SCAR) Inlet and the Cabinet Inlet area of the northwestern Larsen C ice shelf have extensive surface melt pooling, relatively early in the melt season (Figure 2b).

Other melt-prone regions of the Antarctic Ice Sheet show little evidence of surface meltwater ponds, but there were some indications of wet snow by late December. A few days of melt is evident on the northern George VI Ice Shelf and the Bach Ice Shelf (Figure 1a, top), suggesting at least wet snow formation by late December. As melt progresses further, a bluish tint to true-color visible images would indicate meltwater flooding, but that is not yet seen in Moderate Resolution Imaging Spectroradiometer (MODIS) imagery in NASA Worldview. Conditions may still change significantly through the remainder of the melt season.

Greenland surface melting in 2021

Two near-record melt events occurred in the 2021 melt season for the Greenland Ice Sheet, in late July and in mid-August. During the second event, an unprecedented occurrence of rain at the National Science Foundation’s Summit Station took place, the first to be observed in the satellite era. Overall the melt season was unexceptional, owing to a modest start; however, the mid-August heat wave was both strikingly intense and late in the season by several weeks compared to similar events in the record.

Overview of conditions

Figure 1. Top left, cumulative melt days map of Greenland for the 2021 melt season. Top right, map of the difference in number of melt days for 2021 from the 1981-2010 average melt days for the same period. Bottom, daily melt area for Greenland from April 1st through October 31st, 2021 (blue line) 2020 (green line) and 2019 (orange line). In gray are the mean daily melt area for 1981-2010, the inter-quartile range, and the inter-decile range. Credit: National Snow and Ice Data Center/T. Mote, University of Georgia

Figure 1a. The top left map shows cumulative melt days for the Greenland Ice Sheet during the 2021 melt season. The top right map shows the difference in number of 2021 melt days from the 1981 to 2010 average melt days for the same period. The bottom graph shows the daily melt area for the Greenland Ice Sheet from April 1 through October 31, with 2021 shown in blue, 2020 in green line, and 2019 in orange. The grey areas show the average daily melt area for 1981 to 2010, the inter-quartile range, and the inter-decile range.


Credit: National Snow and Ice Data Center/T. Mote, University of Georgia
High-resolution image

Figure 1b. The top plot shows air temperature as a difference from average, relative to 1981 to 2010, for the period of June 1 through August 31, 2021, in degrees Celsius. The bottom plot shows height difference from average in meters for the 700 millibar pressure level in the atmosphere for the same period. ||Credit: National Snow and Ice Data Center|High-resolution image

Figure 1b. The top plot shows air temperature as a difference from average, relative to 1981 to 2010, for the period of June 1 through August 31, 2021, in degrees Celsius. The bottom plot shows height difference from average in meters for the 700 millibar pressure level in the atmosphere for the same period.

Credit: National Snow and Ice Data Center
High-resolution image

1c. The top three maps show cumulative melt days from left to right from 1981, 2001, and 2021. The bottom graph shows bars for cumulative melt days from 1992 to 2021. Credit: National Snow and Ice Data Center, University of Colorado Boulder, T. Mote, University of Georgia|High-resolution image

Figure 1c. The top three maps show cumulative melt days from left to right from 1981, 2001, and 2021. The bottom graph shows bars for cumulative melt days from 1992 to 2021. Credit: National Snow and Ice Data Center, University of Colorado Boulder, T. Mote, University of Georgia
High-resolution image

Figure 1d. This graph shows air temperatures for the summer months of June, July, and August at Summit, Greenland, for 2008-2020 (all years, shown as grey lines) and the three recent years with above-freezing conditions, 2012, 2019, and 2021. Note, the logarithmic scale exaggerates near-freezing temperatures greater than -5 degrees Celsius (23 degrees Fahrenheit). ||Credit: C. Shuman and M. Schnaubelt, University of Maryland, Baltimore |High-resolution image

Figure 1d. This graph shows air temperatures for the summer months of June, July, and August at Summit, Greenland, for 2008-2020 (all years, shown as grey lines) and the three recent years with above-freezing conditions, 2012, 2019, and 2021. Note, the logarithmic scale exaggerates near-freezing temperatures greater than -5 degrees Celsius (23 degrees Fahrenheit).

Credit: C. Shuman and M. Schnaubelt, University of Maryland, Baltimore. Data courtesy of the National Oceanic and Atmospheric Administration Global Monitoring Laboratory. 

High-resolution image

Surface melting of the Greenland Ice Sheet in 2021 was above the 1981 to 2010 average, and extended far higher in elevation than is typical even in recent years (Figure 1a). However this was largely a result of two short-lived heat waves in late July and mid-August, and total cumulative melt-day area is actually near the average for the past 20 years. There were very few melt events following the extreme event of August 14, with surface melting essentially ending by September 10, unlike some recent years. The number of days with melting was slightly higher than average throughout much of southern and western Greenland and slightly below average in the northeastern area. Small areas of the Scoresby Sund (Kangertittivaq) region had up to 30 days more melting than the average.

Averaged over the island, the past summer was approximately 1 degree Celsius (2 degrees Fahrenheit) warmer than average relative to the 1981 to 2010. Temperatures up to 2 degrees Celsius (4 degrees Fahrenheit) above average prevailed over the eastern coast. The west-central area was not as warm with temperatures only 0.6 degrees Celsius (1 degree Fahrenheit) above average. Higher than average air pressure to the east of Greenland, and lower air pressure to the west, resulted in a more southwest-to-northeasterly flow of air than average (Figure 1b).

Surface melt mapping over four decades of satellite data shows that melting has greatly expanded over the ice sheet, including much more of its northern reaches and far more intense melting along the western coast. While the cumulative total melt area has not changed much in the past 20 years, the level of melting is generally higher and more variable than in the 1990s (Figure 1c).

The air temperature record from Summit, Greenland, for the three warmest summers relative to the range for the entire continuous weather observations (2008 to 2020) shows the increased prevalence of daily record high temperatures in the three years, surpassing 0 degrees Celsius (32 degrees Fahrenheit) four times. Satellite data recorded only one other earlier melt event near the Summit, which took place in 1995. The data from 2021 also shows the unusual nature of the warm event of mid-August, usually a period of rapid cooling on the ice sheet (Figure 1d).

More on the rain event at Summit Station

Figure 2. These three photographs were taken from Summit, Greenland, on August 14, 2021. The rain on snow event caused liquid water raindrops on the surfaces of the structures, and the formation of an ice layer from refrozen rain on snow. || Credit: Alicia Bradley and Zoe Courville|High-resolution image

Figure 2. These three photographs were taken from Summit, Greenland, on August 14, 2021. The rain on snow event caused liquid water raindrops on the surfaces of the structures, and the formation of an ice layer.

Credit: Alicia Bradley and Zoe Courville
High-resolution image

The rain event at Summit on August 14, 2021, was the first occurrence since continuous field observations began at that station in 2008. The rain event prompted a search within the available historical literature for reports of rain high on the Greenland Ice Sheet. As noted in our August report, prior to 1995, when a significant melt event occurred, we infer that both melting and rain were absent at Summit for at least the twentieth century because of an absence of ice layers in the ice cores drilled at the site. The most useful report for early weather observations is Hogue (1964), who provides a comprehensive assessment of available weather records for the early to mid-twentieth century. On rain events over the ice cap, Hogue states:

most precipitation falls as snow, but occasionally rain occurs during the warmer months on the outer margin of the icecap….   Heavy rainfall seldom occurs above 6,000 feet [elevation]. However, Belknap reported a heavy rain at Watkins (a temporary camp) at an elevation of 8,840 feet, in July 1933….  At Dye2 on the west slope [of the ice sheet] near the Arctic Circle at an elevation of 7,650 feet, rain of moderate intensity fell on 1 November 1963….  In the Central Station – Eismitte area, rain and drizzle were each reported once on 20 June and 21 June, 1950, respectively, during a three-year period.

Eismitte is at 3,010 meters (9,875 feet) elevation. For comparison, Summit Station is at 3,216 meters (10,551 feet) elevation, and is 155 kilometers (96 miles) away. No later report of rain at elevations above 2,700 meters (8,800 feet) has been found in the available records. Additional information on climate for the Summit area is found in the references listed at the end of this report.

References

Belknap, 1935: Polar Record , Volume 2 , Issue 9 , January 1935, 32 – 35, doi:10.1017/S0032247400033362.

Bilello and Bates, Jan 1975 Summer climate at selected sites on the Ross Ice Shelf and the Greenland Ice Sheet, CRREL Report SR-216, 22p.

Hogue, D.W., 1964. Environment of the Greenland Ice Cap. U.S. Army Natick Laboratories, Natick, Massachusetts Tech. Rept. ES-14:

Ratziki Elizabeth Contribution to the climatology of Greenland. Expeditions polaires francais. Missions Paul Emile Victor Publications E.P. F. 2112 47 Marechal Fayolle Paris 1960.

 Acknowledgements

Greenland Ice Sheet Today is produced at the National Snow and Ice Data Center by Ted Scambos, Julienne Stroeve, and Lora Koenig with support from NASA. NSIDC thanks Jason Box and Robert Fausto of the Geological Survey of Denmark and Greenland (GEUS), Xavier Fettweis, Christopher Shuman, and Thomas Mote for data and collaboration.

 

Data for daily melt ends for one pole, begins for another

Daily melt extent mapping for the Antarctic Ice Sheet will be restarting soon, while mapping for the Greenland Ice Sheet is suspended for the winter. Calibration of yearly melt detection requires analysis of the springtime snow conditions by a separate program. See our March 18, 2013 post for more discussion of melt calibration. A full analysis for the 2021 melt season on the Greenland Ice Sheet will be coming soon.

Our interactive chart supports a retrospective look at past Greenland melt seasons. This will remain available for our users.

Daily image updates will resume for the Greenland Ice Sheet in April 2022.