Polar regions in Greenland and Antarctica have lost nearly 12 trillion tons of ice since the 1970s, raising global sea levels by three centimeters, according to a report from Northumbria University in the UK. Meanwhile, satellite observations show Arctic sea ice shrinking by 12.2% per decade.
Earth’s polar ice sheets and seasonal sea ice cover are undergoing shifts driven by warming temperatures in both the atmosphere and the ocean. As Earth’s atmosphere and ocean warm, seasonal melting of sea ice increases. This is most notable in the summer, when Arctic sea ice cover reaches its smallest area, known as its minimum extent. Measurements of summer Arctic sea ice extent each year show a shrinkage of 12.2% per decade due to warmer temperatures. Greenland and Antarctica are cold, remote places that most of us will never visit, but they are important to Earth and the environment.
Northumbria University Report Details Twelve Trillion Tons of Ice Loss
Now scientists are issuing a dire warning that these places are melting away. According to a report from Northumbria University in the UK, these polar places have lost nearly 12 trillion tons of ice since the 1970s, raising sea levels by three centimeters. Inside Edition Digital’s Mara Montalbano has more.
These remote regions represent critical indicators for planetary health.
Satellite Data Tracks Arctic Sea Ice Shrinkage
In addition to long-term glacial loss in Greenland and Antarctica, seasonal sea ice in the Arctic follows a seasonal pattern. Colder winter temperatures and darkness help it grow, while warmer summer temperatures rise above freezing, causing sea ice to melt. As part of this seasonal pattern, there is a point when the sea ice stops melting. This point is measured by satellite sensors each year in late September as the minimum extent, or smallest area of the sea ice. Shortly after the melting stops, cooler temperatures will cause sea ice to thicken again, continuing through the winter months.
The measurements have shown that September Arctic sea ice is shrinking at a rate of 12.2% per decade, compared to its average extent during the period from 1981 to 2010. This graph shows the area extent of the Arctic sea ice each September since satellite observations started in 1979. The monthly value shown is the average of daily observations across the month of September during each year as measured from satellites. The data is the latest available and is updated annually. The animated map shows the minimum size of the Arctic sea ice measured each year since 1979, based on satellite observations with the graph of year-to-year changes overlayed. Sea ice extent is one of three key sea ice metrics.
Advanced Satellite Missions Monitor Global Water and Ice Dynamics
Other measurements include related missions:
- Gravity Recovery and Climate Experiment – Follow-On (GRACE-FO): GRACE Follow-On (GRACE-FO) is continuing GRACE’s legacy of tracking Earth’s water movement across the planet.
- ICESat-2: ICESat-2 carries a photon-counting laser altimeter that allows scientists to measure the elevation of ice sheets, glaciers, sea ice, tree canopy height, ocean height, and more – all in unprecedented 3-D detail.
- Surface Water and Ocean Topography (SWOT): U.S. and French oceanographers and hydrologists and international partners have joined forces to develop this satellite mission to make the first global survey of Earth’s surface water, observe the fine details of the ocean’s surface topography, and measure how water bodies change over time.
By combining multi-decadal glacier tracking from institutions like Northumbria University with continuous satellite altimetry from missions like GRACE-FO, ICESat-2, and SWOT, scientists maintain a record of how polar ice reduction continues.
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