Chilly seawater may slow ice loss on the island until 2050, then warming and melting may acceleratePeer-Reviewed Publication
AMERICAN GEOPHYSICAL UNION
American Geophysical Union
15 February 2022
AGU Release No. 22-11
For Immediate Release
This press release and accompanying multimedia are available online at: https://news.agu.org/press-release/blue-blob-near-iceland-could-slow-glacial-melting/
“Blue Blob” near Iceland could slow glacial melting
Chilly seawater may slow ice loss on the island until 2050, then warming and melting may accelerate
AGU press office:
Rebecca Dzombak, +1 (202) 777-7492, news@agu.org (UTC-5 hours)
Contact information for the researchers:
Brice Noël, Utrecht University, b.p.y.noel@uu.nl (UTC+1 hour)
WASHINGTON — A region of cooling water in the North Atlantic Ocean near Iceland, nicknamed the “Blue Blob,” has likely slowed the melting of the island’s glaciers since 2011 and may continue to stymie ice loss until about 2050, according to new research.
The origin and cause of the Blue Blob, which is located south of Iceland and Greenland, is still being investigated. The cold patch was most prominent during the winter of 2014-2015 when the sea surface temperature was about 1.4 degrees Celsius (2.52 degrees Fahrenheit) colder than normal.
The new study uses climate models and field observations to show that the cold water patch chilled the air over Iceland sufficiently to slow ice loss starting in 2011. The model predicts cooler water will persist in the North Atlantic, sparing Iceland’s glaciers until about 2050. Ocean and air temperatures are predicted to increase between 2050 and 2100, leading to accelerated melting.
While cooler water in the North Atlantic offers a temporary respite for Iceland’s glaciers, the authors estimate that without steps to mitigate climate change, the glaciers could lose a third of their current ice volume by 2100 and be gone by 2300. If the country’s 3,400 cubic kilometers (about 816 cubic miles) of ice melt, sea level will rise by 9 millimeters (0.35 inches).
“In the end, the message is still clear,” said lead author Brice Noël, a climate modeler who specializes in polar ice sheets and glaciers at Utrecht University. “The Arctic is warming fast. If we wish to see glaciers in Iceland, then we have to curb the warming.”
The paper is published in the AGU journal Geophysical Research Letters, which publishes high-impact, short-format reports with immediate implications spanning all Earth and space sciences. Its findings may help scientists to better understand the indirect effects of the ocean on glaciers.
“It’s crucial to have an idea of the possible feedbacks in the Arctic because it’s a region that is changing so fast,” Noël said. “It’s important to know what we can expect in a future warmer climate.”
The warming Arctic
Nowhere on Earth has warmed as quickly as the Arctic. Recent studies report the area is warming four times faster than the global average. Iceland’s glaciers steadily shrank from 1995 to 2010, losing an average of 11 gigatons of ice per year. Starting in 2011, however, the speed of Iceland’s melting slowed, resulting in about half as much ice loss, or about 5 gigatons annually. This trend was not seen in nearby, larger glaciers across Greenland and Svalbard.
Noël and his colleagues investigated the cause of this slowdown by estimating the glaciers’ mass balance — how much they grew or melted annually from 1958 to 2019. They used a high-resolution regional climate model that works at the small scale of Iceland’s glaciers to estimate how much snow the glaciers received in winter and how much ice was lost from meltwater runoff in summer. The researchers found that cooler waters near the Blue Blob are linked to observations of lower air temperatures over Iceland’s glaciers and coincide with the slowdown of glacial melting since 2011.
Several researchers have proposed that the Blue Blob is part of the normal sea surface temperature variability in the Arctic. Notably, especially cold winters in 2014 and 2015 led to record cooling, which caused upwelling of cold, deep water, even as ocean temperatures around the region warmed due to climate change.
Before the Blue Blob, a long-term cooling trend in the same region, called the Atlantic Warming Hole, reduced sea surface temperatures by about 0.4 to 0.8 degrees Celsius (0.72 to 1.44 degrees Fahrenheit) during the last century and may continue to cool the region in the future. A possible explanation for the Warming Hole is that climate change has slowed the Atlantic Meridional Overturning Circulation, an ocean current that brings warm water up from the tropics to the Arctic, thus reducing the amount of heat delivered to the region.
The end of Iceland’s glaciers?
Noël projected the future climate of Iceland by combining the same regional climate model with a global climate model to predict how North Atlantic ocean temperatures would affect the glaciers’ fate until 2100, under a scenario of rapid warming. The models predicted that the North Atlantic near Iceland will stay cool, slowing — and perhaps even temporarily stopping — ice loss from the glaciers by the mid-2050s.
The authors verified that the models accurately reconstructed the mass of the glaciers using almost 1,200 measurements of snow depth collected between 1991 and 2019 by colleagues at the University of Iceland and satellite measurements of the elevation and extent of glaciers taken from 2002 to 2019 by co-authors at the Delft University of Technology.
“I think their analysis is very thorough,” said Fiamma Straneo, a physical oceanographer at the Scripps Institution of Oceanography who was not involved in the study. “They have a really state-of-the-art regional atmospheric model for looking at the variability of glaciers.” Straneo thinks this approach could be used to understand changes in other glaciers that occur over land, such as in the Himalayas and Patagonia. “There is very active research in land terminating glaciers because they are one of the largest contributors to sea level rise right now.”
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This research study is published with open access and is freely available. Download a PDF copy of the paper here. Neither the paper nor this press release is under embargo.
Paper title:
“North Atlantic Cooling is Slowing Down Mass Loss of Icelandic Glaciers”
Author information:
- Brice Noël (corresponding author), Michiel R. van den Broeke, Institute for Marine and Atmospheric Research Utrecht, Utrecht University, Utrecht, The Netherlands,
- Guðfinna Aðalgeirsdóttir, Finnur Pálsson, Institute of Earth Sciences, University of Iceland, Reykjavìk, Iceland
- Bert Wouters, Institute for Marine and Atmospheric Research Utrecht, Utrecht University, Utrecht; Department of Geoscience & Remote Sensing, Delft University of Technology, Delft, The Netherlands
- Stef Lhermitte, Jan M. Haacker, Department of Geoscience & Remote Sensing, Delft University of Technology, Delft, The Netherlands
JOURNAL
Geophysical Research Letters
DOI
ARTICLE TITLE
North Atlantic Cooling is Slowing Down Mass Loss of Icelandic Glaciers
ARTICLE PUBLICATION DATE
24-Jan-2022
The warming, it is like a ninja, always hiding and then attacking when you do not expect it.
Stymie ice loss until 2050? They mean global warming ain’t happening?
Sure don’t hear National Snow and Ice Data Center speaking so honestly.
Just in case, I visited https://nsidc.org/ and searched.
NSIDC links to an Arctic Sea Ice Extent graph; https://nsidc.org/arcticseaicenews/charctic-interactive-sea-ice-graph/
A graph that lacks historical observations.
On their “news” page they listed this:
Now that sea ice extent is increasing, NSIDC is moving the goal posts and basically minimizing winter sea ice levels.
Again, no global warming to see here! /s
I’m still not sure what the fuss is about.
From the article: Recent studies report the area is warming four times faster than the global average. Iceland’s glaciers steadily shrank from 1995 to 2010, losing an average of 11 gigatons of ice per year. Starting in 2011, however, the speed of Iceland’s melting slowed, resulting in about half as much ice loss, or about 5 gigatons annually. This trend was not seen in nearby, larger glaciers across Greenland and Svalbard. – article
There is plenty of evidence, including what is appearing nowadays, that at some time in the distant past, Greenland was green, grew grasses and trees, and was part of a warm and toasty planet. What’s the problem there? At some point in the distant past, the entire British Isles were full of volcanoes spitting up lava into an active ocean, which produced some incredibly beautiful formations of six-sided columns, meaning that the lava cooled under water. There are places like this in Romania, too, and I’m guessing that the likelihood of these formations can be found in many places if we just look. Just as deserts take over a green and growing continent (northenr Africa and the Saudi peninsula) and turn them into what seem like wastelands, the cycles of weather that cause such things constantly change. Black Rock Mesa in the USA west is like that, as is what is politely called the Salton Sea.
And so what? It’s part of what the planet does, isn’t it? It is completely out of our control, period. If these people had the common sense to admit that they can’t control anything the planet does, I might pay attention, but this is just a scramble after cash grants and nothing else.
I don’t get the scramble to make a prediction about something that these prognosticators will never see, but I would really like to live long enough to find that they are not very good at forecasting anything. For quite a while, I really did think this was about making forecasts, but it isn’t: it’s nothing but a scramble for cash.
I have seldom been so disappointed.
So, it’s a lot less worse than we thought now, but later it’s going to be a lot worse than we thought.
How many of these folks are going to be around in 2050 to see if there predictions (ooops, projections) turn out to be true?