Nav: Home

Arctic sea ice 2019 wintertime extent is seventh lowest

March 20, 2019

Sea ice in the Arctic appears to have hit its annual maximum extent after growing through the fall and winter. The 2019 wintertime extent reached on March 13 ties with 2007's as the 7th smallest extent of winter sea ice in the satellite record, according to scientists at the NASA-supported National Snow and Ice Data Center and NASA.

This year's maximum extent peaked at 5.71 million square miles (14.78 million square kilometers) and is 332,000 square miles (860,000 square kilometers) below the 1981 to 2010 average maximum - equivalent to missing an area of ice larger than the state of Texas.

The Arctic sea ice cover, an expanse of frozen seawater floating on top of the Arctic Ocean and surrounding seas, thickens and expands during the fall and winter months. The sea ice hits its maximum yearly extent sometime between late February and early April. It thins and shrinks during the spring and summer until it reaches its annual minimum extent in September.

Beyond its seasonal wax and wane cycles, Arctic sea ice extent has been plummeting during both the growing and melting seasons over the last 40 years. The 2019 maximum extent breaks a string of record or near-record lows that started in 2015 -- but that does not necessarily mean that Arctic sea ice is recovering.

"While this year wasn't a record low, the maximum extent still points to there being a sustained decline in winter sea ice," said Melinda Webster, a sea ice scientist at NASA's Goddard Space Flight Center in Greenbelt, Maryland. "The temperatures in the Arctic were a bit higher than average and we saw a lot of ice loss in the Bering Sea, but nothing this winter was as extreme or dramatic compared to recent years and the record lows."

Rising temperatures in the Arctic over the past decades have also thinned the sea ice pack. Multiyear ice, the older and thicker ice that acted like a bastion against melting for the rest of the sea ice cover, has mostly disappeared. A 2018 study led by Ron Kwok, a sea ice researcher with NASA's Jet Propulsion Laboratory in Pasadena, California, found that 70 percent of the ice pack now consists of seasonal ice -- sea ice that grows rapidly in the winter only to melt during the next summer.

"The large changes in ice coverage associated with the loss of the multiyear ice pack have already occurred," Kwok said. "The seasonal ice now represents a larger fraction of the Arctic sea ice cover. Because this young ice is thinner and grows faster in the winter, it is more responsive to weather and makes the sea ice cover respond differently than before. It's not that we won't see new wintertime or summertime record lows in the next years - it's just that the variability is going to be higher."
-end-


NASA/Goddard Space Flight Center

Related Sea Ice Articles:

Evidence: Antarctica's thinning ice shelves causing more ice to move from land into sea
New study provides the first evidence that thinning ice shelves around Antarctica are causing more ice to move from the land into the sea.
Low sea-ice cover in the Arctic
The sea-ice extent in the Arctic is nearing its annual minimum at the end of the melt season in September.
Arctic sea ice 2019 wintertime extent is seventh lowest
Sea ice in the Arctic appears to have hit its annual maximum extent after growing through the fall and winter.
Study shows algae thrive under Greenland sea ice
Microscopic marine plants flourish beneath the ice that covers the Greenland Sea, according to a new study in the Journal of Geophysical Research: Oceans.
ICESat-2 reveals profile of ice sheets, sea ice, forests
With each pass of the ICESat-2 satellite, the mission is adding to datasets tracking Earth's rapidly changing ice.
Arctic cyclone limits the time-scale of precise sea-ice prediction in Northern Sea Route?
Climate change has accelerated sea-ice retreat in the Arctic Ocean, leading to new opportunities for summer commercial maritime navigation along the Northern Sea Route.
Ocean waves following sea ice loss trigger Antarctic ice shelf collapse
Storm-driven ocean swells have triggered the catastrophic disintegration of Antarctic ice shelves in recent decades, according to new research published in Nature today.
New technique more accurately reflects ponds on Arctic sea ice
This one simple mathematical trick can accurately predict the shape and melting effects of ponds on Arctic sea ice, according to new research by UChicago scientists.
Arctic wintertime sea ice extent is among lowest on record
Sea ice in the Arctic grew to its annual maximum extent last week, and joined 2015, 2016 and 2017 as the four lowest maximum extents on record, according to scientists at the NASA-supported National Snow and Ice Data Center (NSIDC) and NASA.
Sea ice algae blooms in the dark
Researchers from Aarhus University have measured a new world record: Small ice algae on the underside of the Arctic sea ice live and grow at a light level corresponding to only 0.02 percent of the light at the surface of the ice.
More Sea Ice News and Sea Ice Current Events

Top Science Podcasts

We have hand picked the top science podcasts of 2019.
Now Playing: TED Radio Hour

Accessing Better Health
Essential health care is a right, not a privilege ... or is it? This hour, TED speakers explore how we can give everyone access to a healthier way of life, despite who you are or where you live. Guests include physician Raj Panjabi, former NYC health commissioner Mary Bassett, researcher Michael Hendryx, and neuroscientist Rachel Wurzman.
Now Playing: Science for the People

#544 Prosperity Without Growth
The societies we live in are organised around growth, objects, and driving forward a constantly expanding economy as benchmarks of success and prosperity. But this growing consumption at all costs is at odds with our understanding of what our planet can support. How do we lower the environmental impact of economic activity? How do we redefine success and prosperity separate from GDP, which politicians and governments have focused on for decades? We speak with ecological economist Tim Jackson, Professor of Sustainable Development at the University of Surrey, Director of the Centre for the Understanding of Sustainable Propserity, and author of...
Now Playing: Radiolab

An Announcement from Radiolab