Icebergs delay Southern Hemisphere future warming

Icebergs delay Southern Hemisphere future warming
Future iceberg discharges from the disintegrating West Antarctic ice-sheet (lower right inlay figure) can lead to a substantial reduction of human-induced warming in the Southern Hemisphere. Anthropogenic warming averaged over the pink shaded region without iceberg effect (black) and for weak (cyan), medium (blue) and strong (dark blue) iceberg discharge scenarios. The other two inlay figures depict the iceberg effect on human-induced warming for the model grid points closest to Buenos Aires (Argentina, orange) and Cape Town (South Africa, green). Credit: Fabian Schloesser

New research, published today in the journal Nature Climate Change, has found that Antarctic icebergs can weaken and delay the effect of Global Warming in the Southern Hemisphere.

Unabated Global Warming threatens the stability of the Antarctic ice sheet. Recent observations reveal a rapid thinning of the Pine Island and Thwaites glacier regions in Antarctica, which can be attributed partly to warming oceans. These findings have raised concerns of an accelerated ice loss of the West Antarctic ice sheet and potential contributions to global sea level rise. Ice loss can occur in the form of melt-induced (liquid) freshwater discharge into the ocean, or through (solid) calving.

With a projected future retreat of the Antarctic ice sheet, scientists expect an intensification of iceberg discharge. Icebergs can persist for years and are carried by winds and currents through the Southern Ocean until they reach warmer waters and ultimately melt. The melting process cools ocean waters like ice cubes in a cocktail glass. Furthermore, freshwater discharge from icebergs impacts currents by lowering ocean salinity. Whether this "iceberg effect'' can slow down or alter future climate change in the Southern Hemisphere has remained an open question.

Climate researchers from the University of Hawaii (USA), the IBS Center for Climate Physics (South Korea), Penn State University (USA) and University of Massachusetts (USA) have now quantified for the first time this effect of Antarctic iceberg calving on future Southern Hemisphere climate. The team ran a series of Global Warming computer simulations, which include the combined freshwater and cooling effects of icebergs on the ocean. The size and number of icebergs released in their model mimics the gradual retreat of the Antarctic ice sheet over a period of several hundred years. By turning on an off the "iceberg effect" in their climate model, the researchers discovered that icebergs can significantly slow down human-induced warming in the Southern Hemisphere, impacting global winds and rainfall patterns.

"Our results demonstrate that the effect of Antarctic melting and icebergs needs to be included in computer model simulations of future climate change. Climate models currently used in the 6th climate change assessment of the Intergovernmental Panel on Climate Change (IPCC) do not account for this process." says Dr. Fabian Schloesser, lead author of the study in Nature Climate Change.

Dr. Tobias Friedrich, coauthor of the study, adds: "To melt the icebergs released over the 21st century in one of our extreme Antarctic ice-sheet retreat scenarios would require 400 times the current annual world energy consumption. Global sea level would rise by about 80 cm, impacting many coastal regions and communities worldwide."

Recent studies have suggested that the impact of Antarctic meltwater discharge on the ocean could lead to further acceleration of ice sheet melting and global sea level rise. The present study paints a more complex picture of the underlying dynamics. Including the cooling effect of icebergs largely compensates for the processes that were previously thought to accelerate Antarctic melting.

"Our research highlights the role of icebergs in global climate change and sea level rise. Depending on how quickly the West Antarctic ice sheet disintegrates, the iceberg effect can delay future warming in cities such as Buenos Aires and Cape Town by 10-50 years." says Prof. Axel Timmermann, corresponding author of the study and Director of the IBS Center for Climate Physics.

The research team plans to further quantify the interplay between ice and and its effect on global sea level with a new computer model that they developed.


Explore further

Warming waters in western tropical Pacific may affect West Antarctic Ice Sheet

More information: Antarctic iceberg impacts on future Southern Hemisphere climate, Nature Climate Change (2019). DOI: 10.1038/s41558-019-0546-1
Journal information: Nature Climate Change

Citation: Icebergs delay Southern Hemisphere future warming (2019, August 12) retrieved 23 August 2019 from https://phys.org/news/2019-08-icebergs-southern-hemisphere-future.html
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Aug 12, 2019
Wasn't warming "settled science"? That is precisely the beauty of science. It is never settled.

Aug 13, 2019
"Climate models currently used in the 6th climate change assessment of the Intergovernmental Panel on Climate Change (IPCC) do not account for this process."

So soil, trees, clouds, and even marine microbes all have an effect on the climate. The IPCC was tasked with finding a human cause for global warming - they 'found' carbon dioxide. They set up their computer programs on that basis.

Seems that there might be a bit more to the warming and cooling of the earth over the ages than just the gas that feeds the trees and crops that feed, clothe and shelter us.....

Aug 13, 2019
Wasn't warming "settled science"? That is precisely the beauty of science. It is never settled.

Yes exactly the evidence for Human Induced Climate Change just grows bigger and bigger by the day, it does not stand still ;) as you sit there looking like an idiot coming up with the dumbest opinions on this site everyday (expected from an antigoracle sockpuppet)

Aug 13, 2019
I posted the following on another site:

"Keep your words soft and sweet, you never know when you might have to eat them"

'Idiot', dumbest' - might be hard to digest. Not the words to encourage the other person to take heed of what you're saying.....

Just the ramblings of an old man who was raised in a gentler kinder era.....

Aug 14, 2019
Either you are a sock of antigoracle or you are new to the site, i have a special way of finding that out, i just need a little time ;) However if you are not him and if you know antigoracle and his numbing goon sockpuppets, you will quickly see that there is absolutely no other words to describe his idiocy ;) You can stand on your head being "nice" this goon has no care for Human Induced Climate Change and will rant the utter most amusing BS the world has seen to prove just how uneducated he is. Not my fault if he boasts about your own stupidity

Aug 14, 2019
"his own stupidity"

Aug 14, 2019
"antigoracle" - please define.

"... your ..." - a slip of the keyboard?

" I have a special way of finding that out, I just need a little time" Take all the time you need. If you go back through this sites earlier pages, look for my style of writing. As often as not I start with a quote and a question. Even if I was using a different "handle", my style would still show through. And I apologize for capitalizing the I's in this quote - in primary school I was taught the King's English - and you know how long Queen Elizabeth II has been on the throne.

Aug 14, 2019
Another steaming load of AGW Cult bullshit.
The only place the Cult can find global warming in Antarctica is exactly where there is intense geothermal activity.
https://www.thegu...tarctica

Despite cooking the data, they must now fabricate more lies to explain why Argentina is not warming.
https://www.youtu...RMV2p5cY

Gobble up, Chicken Littles.

Aug 14, 2019


Gobble up, Chicken Littles.


Shut up, sh!tforbrains.

Aug 14, 2019
And, here is the Cape Town lies, exposed.
https://wattsupwi...-record/

Aug 14, 2019
Just the ramblings of an old man who was raised in a gentler kinder era.....
You must be new here, welcome... some here seem bent on sowing stupidity in a place that never forgets, and you get to see them reap what they've sown ...

Aug 14, 2019
You don't say
antigoracle> Another steaming load of AGW Cult bullshit.
The only place the Cult can find global warming in Antarctica is exactly where there is intense geothermal activity.
https://www.thegu...tarctica

Gobble up, Chicken Littles.

Below the ice sheets
There are tunnels 1000s of miles deep
Spewing out liquid rock
Over 1200°C
Well, the icebergs will soon dampen these larva flows aspirations

Aug 14, 2019
Antarctic icebergs can delay the effect of - Larval Global Warming (LGW)

LGW - I should hope so too
New research, published today in the journal Nature Climate Change, has found that Antarctic icebergs can weaken and delay the effect of Global Warming in the Southern Hemisphere

What with these tunnels 1000s of miles deep spewing out liquid rock
If it was not for these ice sheets
We would be suffering these intermingle torments of climate change
Suffering extremes of climate change for billions of years
For as these larval tubes saw of these dinosaurs
These larval tubes most certainly will see of homo-sapiens

Aug 14, 2019
When the last Homo-Sapiens Shuffles their Mortal Coil

Where their spirit wanders this vacuum with these entire long since departed souls
On looking down on this once planet, now devoid of people
This green and pleasant land
Of forests
Deserts
Grasslands
Tropics
Wild animals
Roaming free
In their billions
Where once homo-sapiens once roamed
Where homo-sapiens once worried
Worried about climate change
For as we look down at these wild animales
Destroying these pristine forests, creating deserts
Creating their own habitats
Creating their own forests
Creating their own climate change
These larval tubes will still be spewing out liquid rock

When our Sun calls, Time Gentlemen - Last Pints Please

Aug 14, 2019
there are ice bergs BECAUSE glaciers grow , now how'd that happpen ?

Aug 14, 2019
granville is CORRECT. The glaciers in Antarctica, as well as in the Arctic, due to volcanic tubes that exude liquid (molten) rock from thousands of miles under the surface of planet Earth are causing the melting of glaciers. The water warms below the ice due to hot liquid lava. Heat rises.
If the Earth turned to such a degree that the State of Hawaii became the magnetic North Pole, Hawaii would have ice fields and glaciers covering the islands, packing them down under hundreds of feet of ice, snow and new glaciers. But the liquid lava from its volcanos would melt the ice. This is Earth.
There is no way to control volcanos and what happens when they blow out. They produce Methane, a gas that is far worse that CO2.

Aug 14, 2019
Either you are a sock of antigoracle or you are new to the site, i have a special way of finding that out, i just need a little time ;) However if you are not him and if you know antigoracle and his numbing goon sockpuppets, you will quickly see that there is absolutely no other words to describe his idiocy ;) You can stand on your head being "nice" this goon has no care for Human Induced Climate Change and will rant the utter most amusing BS the world has seen to prove just how uneducated he is. Not my fault if he boasts about your own stupidity
says helomenelo

You seem so bitter and unhappy. Do you really imagine that YOU are the only one who is concerned about the Earth and the future of mankind? I assure you that you're not.
Your bitterness and verbal whippings of commentators on this site doesn't help the current situation of AGW.

I would suggest that you and your friends convince/coerce the Russians to cease spreading radioactive materials into the oceans.

Aug 14, 2019
OK I see that helomenelo has run to several other phorums all about AGW in the time that posted my above comment. That's all, folks.

Aug 15, 2019


Gobble up, Chicken Littles.


Shut up, sh!tforbrains.
says Castroagogo

But antigoracle presented some very valid arguments in the YouTube video about 'heat islands', and the article from The Guardian. They continue to cook the temperature record to include the temps from 'heat island' such as New York City and other sweltering cities in the Northeast of the US. That many humans and tall buildings that absorb heat from the Sun should NOT be included as a part of 'global warming' temperatures because it is highly inaccurate. The city temps should be a separate category because not everyone lives in a city with concrete sidewalks and asphalt streets/roads. Dig up all that concrete/asphalt and tear down tall buildings and that would lower the temperatures in those areas. More city parks and more tree-lined streets would make a big difference. But no one cares enough to get that done. All talk, no action - as they say.

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