Atlantic Current Could Falter Before 2100

Atlantic Current Could Falter Before 2100

The Atlantic Ocean Circulation carries relatively warm water from the Gulf of Mexico to northwestern Europe. Image: Sven Baars, University of Groningen

The Atlantic current won’t come to a full stop the day after tomorrow. But it could face a temporary halt later this century.

European scientists think they have settled one of the more alarming questions of the climate crisis: the potential collapse of the Atlantic current, the Gulf Stream that delivers heat from the tropics to the Arctic.

The answer is clear. Total collapse is not likely for another 1000 years. But there is roughly a one in six chance in the next century that the flow of the north Atlantic current may temporarily halt or falter because of climate change.

That is because faster melting of the Greenland ice cap, and more freshwater in the Arctic Ocean, could trigger a slowdown in what scientists like to call the Atlantic meridional overturning circulation.

And a team of US researchers has separately highlighted one of the potential mechanisms of ocean change: for every 1°C rise in average global temperature, there will be roughly six days fewer on which many of the world’s rivers are frozen, which will mean more freshwater in the northern seas.

The findings are based in the first case on sophisticated use of computer simulations, and in the second on the careful study of 400,000 satellite images collected over more than 30 years.

“The Dutch scientists now think that the likelihood of even a temporary halt is only 15%. This is more or less the chance offered in the grim game of Russian roulette”

Researchers from the universities of Groningen and Utrecht say, in the journal Scientific Reports, that they modelled the likelihood and impact of small changes in the flow of freshwater into the ocean at high latitudes.

The Atlantic current – sometimes called the Gulf Stream – is a massive flow of warm, salty water from the tropics to the Arctic that keeps  northwestern Europe much warmer than, for example, the same latitudes of North America.

As the water flows north, it cools and becomes more dense, and begins to sink below the fresh meltwater of the summer Arctic: the cold, dense, salty water then flows along the sea bed southwards, and this one dramatic global oceanic conveyor belt ultimately delivers nutrients and dissolved oxygen to the Southern Ocean. It also stores dissolved carbon dioxide, distributes heat and moderates high latitude weather.

But in the past 150 years the flow has been weakening, and there have been fears that the circulation could halt entirely, with unforeseeable consequences. This notional failure became the trigger for a 2004 disaster movie called The Day After Tomorrow. Something so sudden and catastrophic as the Hollywood version was never going to happen – but there have been repeated fears that the weakening could continue, and tip the planet’s climate into a new and potentially dangerous state.

The Dutch scientists now think that the likelihood of even a temporary halt is only 15%. This is more or less the chance offered in the grim game of Russian roulette, in which a player spins a six-chambered revolver with one bullet in it, and points it at his or her head.

River ice lost

Their model simulated small changes in the delivery of freshwater. This is likely to accelerate however, according to research in the journal Nature. Researchers combed through 407,880 satellite pictures taken between 1984 and 2018, to find that 56% of rivers were affected by winter freezing, which masked altogether 87,000 square kilometres of water surface.

Freezing is important to both humans and wild things: frozen rivers traditionally have provided good surfaces for ground transport in the high latitudes. The act of freezing also regulates greenhouse gas emissions that would otherwise escape from the rivers. Ice-jams during the spring melt can trigger flooding, which – though damaging to human settlements – spreads fresh water, nutrients and sediments around the flood plains.

But these benefits are at risk. The researchers found that river and lake surfaces were freezing ever later, as global temperatures crept up, and that the world had lost 2.5% of its river ice in the last 30 years.

If the world’s nations stick to the agreement reached in Paris in 2015 and contain global heating to just 2°C above the average for most of human history, then by the end of the century the world could see a reduction of another 16 days in the length of ice cover, compared with the present, they calculate.

If they achieve the Paris ideal of no more than 1.5°C, this extra ice-free period could be reduced to just over seven days. Right now, global average temperatures are already 1°C above the historic average, and the planet is on course for a warming by the end of the century of more than 3°C. − Climate News Network

About the Author

Tim Radford, freelance journalistTim Radford is a freelance journalist. He worked for The Guardian for 32 years, becoming (among other things) letters editor, arts editor, literary editor and science editor. He won the Association of British Science Writers award for science writer of the year four times. He served on the UK committee for the International Decade for Natural Disaster Reduction. He has lectured about science and the media in dozens of British and foreign cities. 

Science that Changed the World: The untold story of the other 1960s revolutionBook by this Author:

Science that Changed the World: The untold story of the other 1960s revolution
by Tim Radford.

Click here for more info and/or to order this book on Amazon. (Kindle book)

This Article Originally Appeared On Climate News Network

Related Books

Climate Change: What Everyone Needs to Know

by Joseph Romm
0190866101The essential primer on what will be the defining issue of our time, Climate Change: What Everyone Needs to Know® is a clear-eyed overview of the science, conflicts, and implications of our warming planet. From Joseph Romm, Chief Science Advisor for National Geographic's Years of Living Dangerously series and one of Rolling Stone's "100 people who are changing America," Climate Change offers user-friendly, scientifically rigorous answers to the most difficult (and commonly politicized) questions surrounding what climatologist Lonnie Thompson has deemed "a clear and present danger to civilization.". Available On Amazon

Climate Change: The Science of Global Warming and Our Energy Future second edition Edition

by Jason Smerdon
0231172834This second edition of Climate Change is an accessible and comprehensive guide to the science behind global warming. Exquisitely illustrated, the text is geared toward students at a variety of levels. Edmond A. Mathez and Jason E. Smerdon provide a broad, informative introduction to the science that underlies our understanding of the climate system and the effects of human activity on the warming of our planet.Mathez and Smerdon describe the roles that the atmosphere and ocean play in our climate, introduce the concept of radiation balance, and explain climate changes that occurred in the past. They also detail the human activities that influence the climate, such as greenhouse gas and aerosol emissions and deforestation, as well as the effects of natural phenomena.  Available On Amazon

The Science of Climate Change: A Hands-On Course

by Blair Lee, Alina Bachmann
194747300XThe Science of Climate Change: A Hands-On Course uses text and eighteen hands-on activities to explain and teach the science of global warming and climate change, how humans are responsible, and what can be done to slow or stop the rate of global warming and climate change. This book is a complete, comprehensive guide to an essential environmental topic. Subjects covered in this book include: how molecules transfer energy from the sun to warm the atmosphere, greenhouse gases, the greenhouse effect, global warming, the Industrial Revolution, the combustion reaction, feedback loops, the relationship between weather and climate, climate change, carbon sinks, extinction, carbon footprint, recycling, and alternative energy. Available On Amazon

From The Publisher:
Purchases on Amazon go to defray the cost of bringing you InnerSelf.comelf.com, MightyNatural.com, and ClimateImpactNews.com at no cost and without advertisers that track your browsing habits. Even if you click on a link but don't buy these selected products, anything else you buy in that same visit on Amazon pays us a small commission. There is no additional cost to you, so please contribute to the effort. You can also use this link to use to Amazon at any time so you can help support our efforts.

 

follow InnerSelf on

facebook icontwitter iconyoutube iconinstagram iconpintrest iconrss icon

 Get The Latest By Email

Weekly Magazine Daily Inspiration

EVIDENCE

Blue water surrounded by dead white grass
Map tracks 30 years of extreme snowmelt across US
by Mikayla Mace-Arizona
A new map of extreme snowmelt events over the last 30 years clarifies the processes that drive rapid melting.
White sea ice in blue water with the sun setting reflected in the water
Earth’s frozen areas are shrinking 33K square miles a year
by Texas A&M University
The Earth’s cryosphere is shrinking by 33,000 square miles (87,000 square kilometers) per year.
wind turbines
A controversial US book is feeding climate denial in Australia. Its central claim is true, yet irrelevant
by Ian Lowe, Emeritus Professor, School of Science, Griffith University
My heart sank last week to see conservative Australian commentator Alan Jones championing a contentious book about…
image
Reuters' Hot List of climate scientists is geographically skewed: why this matters
by Nina Hunter, Post-Doctoral Researcher, University of KwaZulu-Natal
The Reuters Hot List of “the world’s top climate scientists” is causing a buzz in the climate change community. Reuters…
A person holds a shell in their hand in blue water
Ancient shells hint past high CO2 levels could return
by Leslie Lee-Texas A&M
Using two methods to analyze tiny organisms found in sediment cores from the deep seafloor, researchers have estimated…
image
Matt Canavan suggested the cold snap means global warming isn't real. We bust this and 2 other climate myths
by Nerilie Abram, Professor; ARC Future Fellow; Chief Investigator for the ARC Centre of Excellence for Climate Extremes; Deputy Director for the Australian Centre for Excellence in Antarctic Science, Australian National University
Senator Matt Canavan sent many eyeballs rolling yesterday when he tweeted photos of snowy scenes in regional New South…
Ecosystem sentinels sound alarm for the oceans
by Tim Radford
Sea birds are known as ecosystem sentinels, warning of marine loss. As their numbers fall, so could the riches of the…
Why Sea Otters Are Climate Warriors
Why Sea Otters Are Climate Warriors
by Zak Smith
In addition to being one of the cutest animals on the planet, sea otters help maintain healthy, carbon-absorbing kelp…

LATEST VIDEOS

The Great Climate Migration Has Begun
The Great Climate Migration Has Begun
by Super User
The climate crisis is forcing thousands around the world to flee as their homes become increasingly uninhabitable.
The Last Ice Age Tells Us Why We Need To Care About A 2℃ Change In Temperature
The Last Ice Age Tells Us Why We Need To Care About A 2℃ Change In Temperature
by Alan N Williams, et al
The latest report from the Intergovernmental Panel on Climate Change (IPCC) states that without a substantial decrease…
Earth Has Stayed Habitable For Billions Of Years – Exactly How Lucky Did We Get?
Earth Has Stayed Habitable For Billions Of Years – Exactly How Lucky Did We Get?
by Toby Tyrrell
It took evolution 3 or 4 billion years to produce Homo sapiens. If the climate had completely failed just once in that…
How Mapping The Weather 12,000 Years Ago Can Help Predict Future Climate Change
How Mapping The Weather 12,000 Years Ago Can Help Predict Future Climate Change
by Brice Rea
The end of the last ice age, around 12,000 years ago, was characterised by a final cold phase called the Younger Dryas.…
The Caspian Sea Is Set To Fall By 9 Metres Or More This Century
The Caspian Sea Is Set To Fall By 9 Metres Or More This Century
by Frank Wesselingh and Matteo Lattuada
Imagine you are on the coast, looking out to sea. In front of you lies 100 metres of barren sand that looks like a…
Venus Was Once More Earth-like, But Climate Change Made It Uninhabitable
Venus Was Once More Earth-like, But Climate Change Made It Uninhabitable
by Richard Ernst
We can learn a lot about climate change from Venus, our sister planet. Venus currently has a surface temperature of…
Five Climate Disbeliefs: A Crash Course In Climate Misinformation
The Five Climate Disbeliefs: A Crash Course In Climate Misinformation
by John Cook
This video is a crash course in climate misinformation, summarizing the key arguments used to cast doubt on the reality…
The Arctic Hasn't Been This Warm For 3 Million Years and That Means Big Changes For The Planet
The Arctic Hasn't Been This Warm For 3 Million Years and That Means Big Changes For The Planet
by Julie Brigham-Grette and Steve Petsch
Every year, sea ice cover in the Arctic Ocean shrinks to a low point in mid-September. This year it measures just 1.44…

LATEST ARTICLES

trees to plant for climate2
Plant These Trees To Improve City Life
by Mike Williams-Rice
A new study establishes live oaks and American sycamores as champions among 17 “super trees” that will help make cities…
north sea sea bed
Why We Must Understand Seabed Geology To Harness The Winds
by Natasha Barlow, Associate Professor of Quaternary Environmental Change, University of Leeds
For any country blessed with easy access to the shallow and windy North Sea, offshore wind will be key to meeting net…
3 wildfire lessons for forest towns as Dixie Fire destroys historic Greenville, California
3 wildfire lessons for forest towns as Dixie Fire destroys historic Greenville, California
by Bart Johnson, Professor of Landscape Architecture, University of Oregon
A wildfire burning in hot, dry mountain forest swept through the Gold Rush town of Greenville, California, on Aug. 4,…
China Can Meet Energy and Climate Goals Capping Coal Power
China Can Meet Energy and Climate Goals Capping Coal Power
by Alvin Lin
At the Leader’s Climate Summit in April, Xi Jinping pledged that China will “strictly control coal-fired power…
Blue water surrounded by dead white grass
Map tracks 30 years of extreme snowmelt across US
by Mikayla Mace-Arizona
A new map of extreme snowmelt events over the last 30 years clarifies the processes that drive rapid melting.
A plane drops red fire retardant on to a forest fire as firefighters parked along a road look up into the orange sky
Model predicts 10-year burst of wildfire, then gradual decline
by Hannah Hickey-U. Washington
A look at the long-term future of wildfires predicts an initial roughly decade-long burst of wildfire activity,…
White sea ice in blue water with the sun setting reflected in the water
Earth’s frozen areas are shrinking 33K square miles a year
by Texas A&M University
The Earth’s cryosphere is shrinking by 33,000 square miles (87,000 square kilometers) per year.
A row of male and female speakers at microphones
234 scientists read 14,000+ research papers to write the upcoming IPCC climate report
by Stephanie Spera, Assistant Professor of Geography and the Environment, University of Richmond
This week, hundreds of scientists from around the world are finalizing a report that assesses the state of the global…

 Get The Latest By Email

Weekly Magazine Daily Inspiration

New Attitudes - New Possibilities

InnerSelf.comClimateImpactNews.com | InnerPower.net
MightyNatural.com | WholisticPolitics.com | InnerSelf Market
Copyright ©1985 - 2021 InnerSelf Publications. All Rights Reserved.