During wintertime in the northern hemisphere, temperatures drop and Arctic sea ice steadily grows before it starts melting in March. Yet every winter for the past several years, its growth appears to be slowing. This season is proving no different.
The latest reports available Monday show that the Arctic sea ice was at the lowest it’s ever been for this time of year since records began more than three decades ago, according to daily readings from the National Snow and Ice Data Center.
“I have a feeling the February sea ice might be the lowest, continuing the record lowest in January,” said Julienne Stroeve, senior research scientist at the National Snow and Ice Data Center. “Air temperatures in the Arctic are warmer than normal … near the poles, for example, about 8 Celsius above normal.”
Sea ice is frozen water that grows and melts on the ocean surface. During its life cycle, sea ice becomes the solid base that wildlife and native communities need to survive. So diminishing sea ice is problematic for the Arctic ecology that includes everything from sea ice algae to migratory birds to marine mammals.
“The seals pup on the ice, so they need it to reproduce. Bears hunt on the ice. They hunt the seals. All these things are very tightly correlated with the extent of the sea ice,” said Raymond Sambrotto, associate research professor at Columbia University Lamont-Doherty Earth Observatory, in an interview with ThinkProgress.
But sea ice also helps moderate planetary climate with the albedo effect that reflects excessive sunlight back into space. In turn, dwindling sea ice creates large areas of open water that causes the Earth to absorb more of the sun’s solar energy, warming the ocean, the region, and thawing permafrost that holds harmful greenhouse gasses.
By all accounts, sea ice growth has been sluggish this winter. This has happened as 2015 was the warmest year on record. In January, the Arctic averaged about 13.5°F (7.5°C) above average, leading to a new record low of Arctic sea ice extent for the month. Extreme warmth in the region sent sea ice to a new record low for that month, as sea ice extent was 402,000 square miles below average, according to the National Snow and Ice Data Center.
The growth in sea ice then stalled for some two weeks last month, prompting concerns in scientists who thought ice had reached its maximum extent several weeks before its usual time for the second year in a row. “We were thinking that February 9th might have been the maximum,” said Stroeve to ThinkProgress. But in the last few days and particularly over the weekend, however, ice started growing, reaching an extent of 14,336 million square kilometers — or 5,535 million square miles — still the lowest it’s been at this time of year since 2006.
CREDIT: National Snow and Ice Data Center
It’s too soon to say whether the latest data show the maximum extent of the season since sea ice normally keeps growing for a couple of weeks in March, yet researchers note that temperatures seem poised to stay anomalously warm.
“I don’t expect a whole lot of ice to keep happening,” said Stroeve, who went on to add that “these changes that we are seeing are in line with what we understand is happening in the climate system.”
So global warming is likely playing a role in the dwindling sea ice that puts man and planet at risk, as researchers say this ice loss has been happening for the last few decades. “There is a long-term decline trend in winter sea ice,” said Rong Zhang, an oceanographer at the National Oceanic and Atmospheric Administration’s Geophysical Fluid Dynamics Laboratory, to ThinkProgress. “So this lowest record this winter is a fluctuation on top of a long-term decline trend.”
What’s more, Stroeve theorizes that Jonas, the super storm that hit the east coast of the United States in January, added to this year’s ice problem. She is almost certain about it though she is verifying the data for an upcoming report.
The storm “brought warm humid air into the Arctic and especially [into] the Kara and the Barents seas,” she said while referring to seas located in between Greenland and Russia. “It could have been enough to one, prevent ice growth and two, help keep the ice pushed north towards the poles.”
Unusually powerful storms like Jonas, meanwhile, are thought to increase as human-caused climate change accelerates. “There is peer-reviewed science that now suggests that climate change will lead to more of these intense, blizzard-producing nor’easters, for precisely the reason we’re seeing this massive storm — unusually warm Atlantic ocean surface temperatures,” said Michael Mann, Director of Penn State’s Earth System Science Center, to ThinkProgress last month.
If these kinds of projections materialize, then what some scientists called anomalous ice growth may soon become the norm, and incidentally affect the health of the equally valuable summer sea ice that in part depends on earlier growth. “The Arctic is warming in all seasons, and the largest losses of ice are happening in summer,” Stroeve said.