A new study predicts that any sea level rise in the world’s most southern continent will be countered by an increase in snowfall, associated with a warmer Polar atmosphere. Using modern methods to calculate projected changes to sea levels, researchers discovered that the two ice sheets of Greenland and Antarctica respond differently, reflecting their very distinct local climates.
The paper, published today in Geophysical Research Letters, is based on the new generation of climate models which are used in the newly published Intergovernmental Panel on Climate Change (IPCC) Sixth Assessment Report, reviewing scientific, technical, and socio-economic information regarding climate change.
The project brought together over 60 researchers from 44 institutions to produce, for the first time, process-based community projections of the sea level rise from the ice sheets. This particular paper focusses on one aspect of the overall project which is how the new generation of climate model projections used in the current IPCC assessments differ from the early generation in their impact on the ice sheets.
Professor Tony Payne, Head of Bristol’s School of Geographical Sciences said the team were trying to establish whether the projected sea level rise from the new generation of climate models was different from the previous generation. “The new models generally predict more warming than the previous generation but we wanted to understand what this means for the ice sheets.” he said. “The increased warming of the new models results in more melt from the Greenland ice sheet and higher sea level rise by a factor of around 1.5 at 2100.
“There is little change, however, in projected sea level rise from the Antarctic ice sheet. This is because increased mass loss triggered by warmer oceans is countered by mass gain by increased snowfall which is associated with the warmer Polar atmosphere.”
Abstract
Projections of the sea level contribution from the Greenland and Antarctic ice sheets (GrIS and AIS) rely on atmospheric and oceanic drivers obtained from climate models. The Earth System Models participating in the Coupled Model Intercomparison Project phase 6 (CMIP6) generally project greater future warming compared with the previous Coupled Model Intercomparison Project phase 5 (CMIP5) effort. Here we use four CMIP6 models and a selection of CMIP5 models to force multiple ice sheet models as part of the Ice Sheet Model Intercomparison Project for CMIP6 (ISMIP6). We find that the projected sea level contribution at 2100 from the ice sheet model ensemble under the CMIP6 scenarios falls within the CMIP5 range for the Antarctic ice sheet but is significantly increased for Greenland. Warmer atmosphere in CMIP6 models results in higher Greenland mass loss due to surface melt. For Antarctica, CMIP6 forcing is similar to CMIP5 and mass gain from increased snowfall counteracts increased loss due to ocean warming.
Plain Language Summary
The melting of the Greenland and Antarctic ice sheets (GrIS and AIS) will result in higher sea level in the future. How sea level will change depends in part on how the atmosphere and ocean warm and how this affects the ice sheets. We use multiple ice sheet models to estimate possible future sea levels under climate scenarios from the models participating in the new Coupled Model Intercomparison Project phase 6 (CMIP6), which generally indicate a warmer world that the previous effort (CMIP5). Our results show that the possible future sea level change due Antarctica is similar for CMIP5 and CMIP6, but the warmer atmosphere in CMIP6 models leads to higher sea-level contributions from Greenland by the end of the century.
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There is panic among climate caccalogists: Rain falls in Greenland ice cap for first time on record !“An umbrella, an umbrella! My kingdom for an umbrella!” cried Harald Bluetooth.
Professor Tony Payne, Head of Bristol’s School of Geographical Sciences said: blah blah…
Tony, your ‘coffee grows in Brazil’ discipline must have skipped McKittrick’s gutting of Models here at WUWT the other day because of inappropriate use and tuning of the models you used. Yeah, I know the math was above your pay grade. So, here is a correction to your forecast:
The models are running too hot and the new one is even worse. The real outlook for Antarctica is for continued cooling. You could, quite competently, check for future destruction of Brazilian coffee plantations from Antarctic wintry blasts and scoop your geography colleagues.
The cooling will reduce your ‘calculated’ warming and snowing, but also reverse ice loss but only slightly. You see Tony, the average annual T there is -56°C, so even at a blistering 2°C of warming a a century, it would take over 20 centuries before we had to start worrying too much, and remember it’s been iced up for 36 million years! No. No, really.
Now, add cooling in light of this, to Greenland, and cooling to the oceans and both sealevel and CO2 will go down!
This is a good time to get back into coffee in Brazil and Bully Beef in Argentina, Tony. We’ve reached Peak Climate Scientist and the tipping point for their services is in the offing.
Betting on peak stupid is a fool’s errand.
Who needs a model – ice, water, water vapor, are the three phases of the earth’s climate control system.
What melting ice sheet ?
http://nsidc.org/data/seaice_index/images/daily_images/S_stddev_timeseries.png
AGW true believers use sea ice an “ice sheet” interchangeably, to best effect, when defrauding the general public. It’s rather like their insistence on confusing weather and climate as it suits their narrative. They only use measured data when it favorably follows that same narrative, otherwise it’s models all the way down.
This one?
Large melt events change the story of 2021 | Greenland Ice Sheet Today (nsidc.org)
Did you read that Griff?
You must have missed this
“As a result the 2021 net run off is below average as of this post”
The Arctic sea ice mean for July is now higher than in 2007. That is of much greater importance compared to what happens on Greenland. …
But of course they do. They project more warming because the programmers were told to project more warming. There is no other reason for them to do so.
However, further down in the paragraph they say, “The increased warming of the new models” … an admission that it’s the models that are warming, not the Antarctic.
Using models to fight models. Brilliant.
Well, this is truly astonishing! An island ice-continent under the influence of a polar cell and surrounded by a complete ocean-track Ferrel cell responds to climatic changes differently from an inland ice-ocean. A land-locked ocean that is also under the influence of a polar cell but is almost completely surrounded by a land dominated Ferrel cell where east-tracking ocean weather systems encounter a significant continental scale transverse mountain barrier that forms an atmospheric dam. Who’d have thunk it?
Do I really need to add the sarc tag?
Meereisportal has a great graphic showing monthly means for sea ice at both poles. I was just looking at Antarctica for the month of November. The largest drop in sea ice on that graph was clearly caused by the large El Nino which peaked in early 2016. The southern sea ice then climbs all the way back to above average levels within 4 years. This look at all 12 months of the year gives one a much greater understanding of the yearly trend. …
… https://www.meereisportal.de/en/seaicetrends/monthly-mean-antarctic/