This remaining possible inaccuracy is now a small fraction of the total melt-day mapping for the year (less than 5 percent). However, somewhat unusual conditions in the upper Jakobshavn Gletscher region, inferred to be due to a heavy surface frost event sometime earlier in the spring, prevent a complete removal of the anomalous early-melt area.
We have in part corrected the parameters for determining melt from the satellite data by adjusting the baseline reference period used to characterize the pre-melting springtime snowpack. Moreover, at least some melting has now occurred over most of the ice sheet, even at high elevations, and this preconditions the snow for further melting by warming and darkening the upper layers. Melt-day extent over the southern portion of the ice sheet is now at a record high for the 45-year satellite record.Ī significant increase in the estimated (modelled) run-off has occurred in the South Dome and Zachariæ Isstrøm Glacier regions, exacerbated by the below-average net accumulation in the southern and northeastern portions of the ice sheet at the end of spring. Total melt-day extent, the sum of daily melt extents for the season so far, is now sixth highest overall. The total number of days with melting are now well above average throughout the southern and southwestern portions of the ice sheet by up to 5 to 15 days, and along its northern flank by about 10 days. Several widespread melting events covering about 800,000 square kilometers (302,000 square miles) or up to 50 percent of the ice sheet occurred on June 27, July 6 to 7, and July 11, as several pulses of warm air swept across the southern portion of the ice sheet and northward around the northern coast. Mote, University of Georgiaīeginning around June 23, the areal extent of Greenland’s surface melting and runoff increased significantly. The gray lines and bands depict the average daily melt area for 1981 to 2010, the interquartile range, and the interdecile range.Ĭredit: National Snow and Ice Data Center/T. The bottom graph shows the daily melt area for Greenland from April 1st through August 6th for 2023 and several of the near-record melt years in this century. The top right map illustrates the difference from the 1981 to 2010 average melt days for the same period. The top left map illustrates cumulative melt days on the Greenland Ice Sheet for the 2023 melt season through July 12. We post analysis periodically as conditions warrant.Ĭlick an image for a high-resolution version.įigure 1. Get daily satellite images and information about melting on the Greenland ice sheet. Occasional short-term delays and data outages do occur and are usually resolved in a few days. However, visitors may notice that the date on the image is occasionally more than one day behind.
TEMPERATURE NOW UPDATE
The daily image update is produced from near-real-time operational satellite data, with a data lag of approximately one day. The daily image update isn’t current why? Read about the data and other problems which occasionally occur in near-real-time data. We are working to improve the ice sheet mask. This issue does not affect trends for the entire ice sheet. This is a false melt signal from seasonal snow and patchy ice areas, where our method of determining surface melting does not work. Note that the northeast coast (northern Peary Land and Kronprince Christian Land) is showing erroneous melt pixels. The Cumulative Melt Days image (right) shows the total number of days that melt occurred, year to date.Īreas along the coast are masked out because the satellite sensor’s resolution is not fine enough to distinguish ice from land when a pixel overlaps the coast. The Daily Melt image (left) shows where the surface of the Greenland Ice Sheet showed melt on that day. The Greenland melt images here are updated daily, with a one-day lag.
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