Global Snow and Ice - June 2018
Beginning in November 2017, NCEI will use version 3 of the National Snow and Ice Data Center's (NSIDC) monthly sea ice extent index. All historical monthly sea ice extent values will be updated to version 3, but historical reports will not be updated. For additional information on the methodology changes and comparisons to version 2, please visit the National Snow and Ice Data Center.
Sea Ice Extent
|June 2018||Sea Ice Extent||
(out of 40 years)
|million km2||million mi2||Year(s)||million km2||million mi2|
Data Source: National Snow and Ice Data Center (NSIDC). Period of record: 1979–2018 (40 years)
According to the National Snow and Ice Data Center (NSIDC), the Northern Hemisphere (Arctic) sea ice extent — which is measured from passive microwave instruments onboard NOAA satellites — averaged for June 2018 was 10.71 million square km (4.14 million square miles), 1.06 million square km (405,000 square miles), or 9.0 percent, below the 1981-2010 average. This was the fourth smallest June Arctic sea ice extent on record. The June Arctic sea ice extents were smaller in 2010, 2012, and 2016. Sea ice contracted rapidly during early and late June with a slowdown mid-month. At the end of June, below-average sea ice coverage was observed in the Chukchi, Barents, Laptev and East Siberian Seas. The seasonal ice retreat in the Chukchi Sea slowed during June after record low extent in the basin for several months. In Hudson Bay, below-average sea ice was observed in western areas of the bay with above-average ice coverage across eastern regions. June Arctic ice extent is decreasing at an average rate of 4.0 percent per decade.
The June Southern Hemisphere sea ice extent was 12.85 million square km (4.96 million square miles), which was 500,000 square km (190,000 square miles), or 3.8 percent, below the 1981-2010 average. This was the eighth smallest June Southern Hemisphere sea ice extent on record. Antarctic sea ice rapidly expanded during June after approaching near-record low levels in early May. By the end of June, the daily sea ice extent was near the 1981-2010 average. Most regions observed near-average ice coverage with below-average conditions in the northern Davis Sea. Southern Hemisphere June sea ice extent is increasing at an average rate of 1.2 percent per decade, with substantial inter-annual variability.
For further information on the Northern and Southern Hemisphere snow and ice conditions, please visit the NSIDC News page.