Arctic Sea Ice: June 2024 Status

Overall typical for recent years, but with regional extremes

Sea ice in the Arctic is is following the normal seasonal decline. Mid-June ice extent this year is very similar to the past two years though lower than 2016-2021, but still well below the 1981-2010 10-90th percentile window. Overall, as of June 17, 2024, sea ice extent was the 10th lowest since 1979. However, after accounting for trend, with three months to go in the Arctic melt season this is not an especially useful predictor of the September minimum. That will be determined by the weather and ocean factors in the coming months.

Fig. 1 Arctic-wide daily sea ice extent to June 17, 2024. The past three years are plotted, as well as the 1981-2010 median (thick gray line) and the 10th-90th percentile band (gray shading). Graphic courtesy National Snow and Ice Data Center

Sea ice concentration and thickness

Figure 2 shows the Arctic sea ice concentration as of June 17, along with the 1981-2010 median ice edge. Concentrations show a typical early summer pattern, with moderate concentrations increasingly widespread north of the of the ice edge, especially south of 80°N.

Fig. 2 Sea ice concentrations for June 17, 2023. Graphic courtesy National Snow and Ice Data Center.

Sea ice thickness can be tricky in the summer, but the modeled thickness from the Danish Meteorological Institute can still be useful over the high Arctic. This shows the 3 plus meter ice remains confined to the northern Canadian Arctic Islands and north coast of Greenland, with some 2 to 3 meter ice in the Beaufort Sea north of 75°N. The lack of really thick ice north of the Russian coast is notable but is in line with recent years and the loss of old (4 year or more) ice from the Arctic.

Fig. 3 Modeled Arctic sea ice thickness for June 17, 2024. Modeling and images courtesy DMI.

Regional sea ice

Figure 4 shows the rank of the June 17 ice extent in the various basins around the Arctic. There are a couple of standouts here: Hudson Bay has by far the lowest ice extent for this point in the season, 17 percent lower than the previous June 17th minimum ice extent that occurred in 2010. Reminiscent of last summer, the Canadian Arctic Archipelago and Beaufort Sea have very low extent for this point in the season. On the other hand, sea ice extent in Chukchi Sea is the highest since 2000 and 10th highest since 1979.

Fig. 4 Rank of June 17, 2024 sea ice extent in the regional seas of the Arctic for the period 1979 to 2024. Data and base graphic courtesy National Snow and Ice Data Center.

The Bering Sea, Sea of Okhotsk and Gulf of St. Lawrence are shown as “NA”, as any remaining ice is now in the “noise level” of the resolution of the near-real time passive microwave derived product, e.g. the spurious near-shore ice indicated in Fig 2. in Bristol Bay, southwest Alaska and the Gulf of St. Lawrence, between the Newfoundland and Quebec coasts.

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Technical details

The NSIDC Sea Ice Index is based on the comparatively low resolution passive microwave data (nominal 25km² by 25km² but in practice is not that good) and given as the 5-day trailing average, so slightly lags changes in sea ice. At regional to Arctic-wide spatial scales this is usually not significant. Details on the Sea Ice Index are here. The regional daily data is available as an Excel spreadsheet here.

Modeled sea ice thickness and volume from the Danish Meteorological Institute is available here.