Environment

Melting ice floods the Arctic with fresh water, and it may cool Europe

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Sea ice coverage in the Arctic has declined significantly over the last few decades
NASA/Kathryn Hansen
Sea ice coverage in the Arctic has declined significantly over the last few decades
NASA/Kathryn Hansen
NASA calculates that Arctic sea ice is declining at a rate of 12.85 percent per decade
NSIDC/NASA

The Arctic is undergoing a significant transformation as a result of climate change, with the warmer conditions thawing out its sea ice at an increasingly alarming rate. A new NASA-led study has illuminated one of the consequences of this, with satellite data revealing that the ice melt is flooding one of the region’s significant ocean currents with fresh water, which the scientists believe could have a ripple effect across the Atlantic and lead to a cooler Western Europe.

For decades, scientists have been keeping a close eye on Arctic sea ice coverage as an indicator of a warming planet. One 2016 NASA study found the total coverage at the height of the melting season was 40 percent less than in the late 1970s. Another study from Britain’s University of Exeter last year predicted that the Arctic Ocean could experience an ice-free summer within the next 20 years. Today, NASA calculates that Arctic sea ice is declining at a rate of 12.85 percent per decade.

NASA calculates that Arctic sea ice is declining at a rate of 12.85 percent per decade
NSIDC/NASA

In a new study, NASA scientists have drawn on 12 years of satellite data to track the behavior of one of the region’s major ocean currents. Called the Beaufort Gyre, this circular current is key to keeping the environment balanced, gathering fresh water from melting glaciers, rain and river run off which sits above the warmer saltier water to prevent the thawing of sea ice.

But the team’s analysis has revealed that the Beaufort Gyre is now taking in unprecedented amounts of fresh water, enough to almost fill Lake Michigan twice over since the 1990s. According to the scientists, this is being driven by the significant loss of sea ice in the summer and autumn, which also makes the Beaufort Gyre more exposed to winds.

Normally, the gyre gradually releases its fresh water supplies into the Atlantic Ocean, but these increased winds are causing it to spin faster and faster, trapping the fresh water within the current instead. Traditionally, these winds change direction every five to seven years, but for the last 20 have persistently blown the current in a westerly direction. Were the wind to suddenly change direction now, all that built up fresh water could be pumped into the Atlantic Ocean at once.

"If the Beaufort Gyre were to release the excess fresh water into the Atlantic Ocean, it could potentially slow down its circulation,” says Tom Armitage, lead author of the study and polar scientist at NASA's Jet Propulsion Laboratory in Pasadena, California. “And that would have hemisphere-wide implications for the climate, especially in Western Europe.”

This is due to how the Beaufort Gyre interacts with another current important for the Earth’s climate called the Atlantic Meridional Overturning Circulation. When fresh water is released from the Arctic into the North Atlantic Ocean, it cools, sinks to the bottom and pushes water south toward the tropics, before carrying heat from the tropics back toward northern regions of the planet like Europe and North America.

If the Atlantic Meridional Overturning Circulation was to be slowed down in a significant way, it could disrupt one of the key systems that regulate the Earth’s climate. The scientists continue to closely monitor the Beaufort Gyre for this reason.

"What this study is showing is that the loss of sea ice has really important impacts on our climate system that we're only just discovering," says Alex Petty, co-author of the study.

The research was published in the journal Nature Communications.

Source: NASA

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10 comments
Anne Ominous
According to DMI, Arctic ice extent is higher now than in recent years.

http://ocean.dmi.dk/arctic/icecover.uk.php

Also, sources *other than* NASA show no significant trend in Arctic sea ice extent since 2006.
Nobody
The earth is self regulating. A warming trend will trigger a cooling trend. Global warming is just part of a natural cycle and no carbon tax or government control will change that.
CarolynFarstrider
Anne Ominous, you need to explain how your interpretation of http://ocean.dmi.dk/arctic/icecover.uk.php suggests higher polar ice extent today than in recent years. It clearly does not. 2020 figures are already tracking along a position lower than 2 standard deviations away from the longer term average, and the last few years 2016-2019 have been similarly low. No idea who your 'sources other than NASA' might be - why don't you tell us?
Brian M
@Nobody
Yes and we have seen that a number of times over geological time - However the danger is in the speed of change, plus of course climate change can alter what species flourish.

Unfortunately 'Greens' are totally the wrong people to listen to as they have a habit of being irrational.

The biggest and best changes we can make are
1. Reduce the overall population
2. Build defences against rising sea levels
3. Reduce green house gas omissions (population reduction will do most of that)
4. Tidal and barrage energy generation
4. Create carbon sink technology

Driving Electric cars, going vegan, flying less etc., is not going to solve the problem.
Worzel
It's amazing! I see that CO2 is still being erroneously blamed for climate change. It has had no effect on climate in 600 million years. Before the ''Little Ice Age'' the Arctic Northwest passage was open to shipping in summer for decades. So, the present situation is not unprecedented. However, if the cold fresh water is sufficient to deflect the Gulf Stream, that keeps the UK and Western Europe warmer than it would other wise be, the Arctic Ice would return with a vengeance, and people all over Europe would be bemoaning the loss of ''global warming'' because there would be widespread crop failure, and Arctic ice would be able to spread south to levels not seen for hundreds of years.
roddy6667
So, if the climate cooled for some reason, like lack of sunspots or more volcanic activity, Europe would get warmer?
1stClassOPP
So, has anyone ever done a study on the effects of hundreds of rockets shot through earth’s atmosphere into space on climate change? There must be a reaction from that global activity, starting with exhaust gases.
Catweazle
Arctic sea ice is currently increasing and is with one standard deviation of its 1981 - 2010 mean and is at its fifteenth lowest level.
ljaques
Man, NASA-led studyfolk, if you think =that's= bad, look again in =SUMMER=! I think Nobody, Brian, & Worzel have the overall picture. NASA sure hasn't, not since James Hansen gutted the science out of them, installing the Church of AGWK.
El Nacho
"However the danger is in the speed of change" - Brian M


Yes, if global temps jumped 100°C within 2 minutes, then we would all be truly in danger.


According to NASA's Earth Observatory though, "the average global temperature on Earth has increased by a little more than 1° Celsius (2° Fahrenheit) since 1880. Two-thirds of the warming has occurred since 1975, at a rate of roughly 0.15-0.20°C per decade"


Frighteningly mind-boggling stuff, until we remember how at the start of the current Holocene warm period, temps jumped 12°C (22°F) within just 50 years (https://phys.org/news/2008-06-greenland-ice-core-analysis-drastic.html) or a blistering 2.4°C per decade.


Our primitive ancestors together with the flora and fauna at the time not only survived, but thrived. It was the sudden jump in temps that allowed our ancient ancestors to establish communities and civilisations based on agriculture and commerce.


It was when temps trended downwards, such as during the Dark Ages Cold Period and Little Ice Ages that mankind suffered more crop failures, more famine, more pestilence, more diseases, more suffering, more deaths.