Arctic ice melt is ahead of model predictions, I believe, at least those used by the IPCC.

Peter Wadhams, death spiral etc.

So does the BOINC model account for this ?
If not, is there any point running it ?

Some CPDN models forecast the future, or rather "a future", but many models also attempt to understand what caused the past as it is known to have happened: in those "hindcasts" the ice extent would presumably be taken from observations - in which case it doesn't matter that the extents were worse at that time than was forecast at some earlier time.

For forecasts, underestimating the ice loss would be expected to produce a "not quite as bad" world. If the people in that world were to address even that not-quite-as-bad world then they would be better prepared for the worse world that is almost inevitable given our catastrophic indolence.

Here is some interesting information from 2013 -- the Guardian --

http://www.theguardian.com/environment/earth-insight/2013/dec/09/us-navy-arctic-sea-ice-2016-melt

reported by Dr Nafeez Ahmed.

Monday 9 December 2013 13.39 GMT Last modified on Thursday 22 May 2014 11.01 BST

sorry for the Long copy and paste.

<quote>

US Navy predicts summer ice free Arctic by 2016 Is conventional modelling out of pace with speed and abruptness of global warming?

An ongoing US Department of Energy-backed research project led by a US Navy scientist predicts that the Arctic could lose its summer sea ice cover as early as 2016 - 84 years ahead of conventional model projections.

The project, based out of the US Naval Postgraduate School's Department of Oceanography, uses complex modelling techniques that make its projections more accurate than others.

A paper by principal investigator Professor Wieslaw Maslowski in the Annual Review of Earth and Planetary Sciences sets out some of the findings so far of the research project:

"Given the estimated trend and the volume estimate for October�November of 2007 at less than 9,000 km3, one can project that at this rate it would take only 9 more years or until 2016 � 3 years to reach a nearly ice-free Arctic Ocean in summer. Regardless of high uncertainty associated with such an estimate, it does provide a lower bound of the time range for projections of seasonal sea ice cover."

The paper is highly critical of global climate models (GCM) and even the majority of regional models, noting that "many Arctic climatic processes that are omitted from, or poorly represented in, most current-generation GCMs" which "do not account for important feedbacks among various system components." There is therefore "a great need for improved understanding and model representation of physical processes and interactions specific to polar regions that currently might not be fully accounted for or are missing in GCMs."

According to the US Department of Energy describing the project's development of the Regional Arctic System Model (RASM):

"Given that the Arctic is warming faster than the rest of the globe, understanding the processes and feedbacks of this polar amplification is a top priority. In addition, Arctic glaciers and the Greenland Ice Sheet are expected to change significantly and contribute to sea level rise in the coming decades."

Such Arctic changes "could have significant ramifications for global sea level, the ocean thermohaline circulation and heat budget, ecosystems, native communities, natural resource exploration, and commercial transportation."

The regional focus of RASM permits "significantly higher spatial resolution" to represent and evaluate the interaction of "important fine-scale Arctic processes and feedbacks", such as:

"... sea ice deformation, ocean eddies, and associated ice-ocean boundary layer mixing, multiphase clouds as well as land-atmosphere-ice-ocean interactions."

The role of the Department of Energy in backing the research is not surprising considering that President Obama's national Arctic strategy launched in May is focused on protecting commercial and corporate opportunities related to control of the region's vast untapped oil, gas and mineral resources.

The model coheres with the predictions of several other Arctic specialists - namely Prof Peter Wadhams, head of polar ocean physics at Cambridge University and Prof Carlos Duarte, director of the Ocean Institute at the University of Western Australia - who see the disappearance of the Arctic sea ice in the summer of 2015 as likely.

Prof Wadhams is co-author of the controversial Nature paper which calculated the potential economic costs of climate change based on a scenario of 50 Gigatonnes (Gt) of methane being released this century from melting permafrost at the East Siberia Arctic Shelf (ESAS), a vast region of shallow-water covered continental crust. The scenario was first postulated by Natalia Shakhova and Igor Semiletov of the International Arctic Research Centre at the University of Alaska, Fairbanks.

In 2010, Shakhova's team published results showing that 7 teragrammes of methane was bubbling to the surface annually in the ESAS. Last month, she released a new paper in Nature Geoscience updating these findings on the basis of more rigorous measurements using an unmanned underwater vehicle with advanced sonar capability. She found that annual bottom water temperatures have increased over the last 14 years, correlating with a release of about 17 teragrammes of methane a year, accentuated by storms. This conservative estimate is more than double the earlier assessment.

However, the source of these methane emissions remains a matter of dispute, as other scientists investigating the phenomenon point out that while large deposits of methane hydrates could be breaking up, the other possibility is a slow leak of methane that has already gone on for hundreds of years. Christian Berndt, of the GEOMAR/Helmholz Centre for Ocean Research, has speculated that both phenomena could be going on at once, but he admits, "We have no proof."

Despite their latest study uncovering higher levels of methane than previously recognised, Shakhova has also distanced herself from the 'methane bomb' scenario she had once previously posited, noting a lack of direct evidence for the scenario.

Commenting on the study, the US National Snow & Ice Data Centre (NSIDC) observes:

"Ship-based observations show that methane concentrations in the air above the East Siberian Sea Shelf are nearly twice as high as the global average... Layers of sediment below the permafrost slowly emit methane gas, and this gas has been trapped for millennia beneath the permafrost. As sea levels rose at the end of the ice age, the shelf was once again covered by relatively warm ocean water, thawing the permafrost and releasing the trapped methane... In the short-term... methane has a global warming potential 86 times that of carbon dioxide."

Most scientists agree that more research is needed to determine the source and nature of these methane emissions.

But scientists also largely agree that an ice free Arctic in the summer could have serious consequences for the global climate. Some research has pointed out a link between the warming Arctic and changes in the jet stream, contributing to unprecedented weather extremes over the last few years. These extreme events in turn have dramatically impacted crop production in key food basket regions.

A landmark new study in Nature Climate Change finds the melting of the sea ice over the last 30 years at a rate of 8% per decade is directly linked to extreme summer weather in the US and elsewhere in the form of droughts and heatwaves. Lead study author Quihang Tang at the Institute of Geographic Sciences and Natural Resources Research in Beijing said:

"As the high latitudes warm faster than the mid-latitudes because of amplifying effects of melting ice, the west-to-east jet-stream wind is weakened. Consequently, the atmospheric circulation change tends to favour more persistent weather systems and a higher likelihood of summer weather extremes."

The new study supplements earlier research published in Geophysical Research Letters demonstrating a link between Arctic sea ice loss and extreme weather particularly in both the summer and winter, including prolongation of "drought, flooding, cold spells, and heat waves."

Last year Prof Duarte was lead author of a paper in the Royal Swedish Academy of Science's journal AMBIO warning that the Arctic was at risk of passing critical "tipping points" that could lead to a cascading "domino effect once the summer sea ice is lost." Prof Duarte said at the time:

"If set in motion, they can generate profound climate change which places the Arctic not at the periphery but at the core of the Earth system. There is evidence that these forces are starting to be set in motion. This has major consequences for the future of human kind as climate change progresses."

<quote>


Dr Nafeez Ahmed is executive director of the Institute for Policy Research & Development and author of A User's Guide to the Crisis of Civilisation: And How to Save It among other books. Follow him on Twitter @nafeezahmed

http://www.theguardian.com/environment/earth-insight/2013/dec/09/us-navy-arctic-sea-ice-2016-melt

sorry for the Long copy and paste.

Some CPDN models forecast the future, or rather "a future", but many models also attempt to understand what caused the past as it is known to have happened: in those "hindcasts" the ice extent would presumably be taken from observations - in which case it doesn't matter that the extents were worse at that time than was forecast at some earlier time.

For forecasts, underestimating the ice loss would be expected to produce a "not quite as bad" world. If the people in that world were to address even that not-quite-as-bad world then they would be better prepared for the worse world that is almost inevitable given our catastrophic indolence.

Well that's a good point about being prepared , and the root of my question, because my town was flooded during the recent storm surge - and the authorities, basing their defenses on IPCC projections, weren't prepared.

So does the CPDN take into account the latest ice cap data to verify it's models ?

I know there is a bit of a fight over this because Wadhams goes with a non linear ice retreat based on observation - leading to imminent ice cap loss, whereas most modellers draw a straight line through the data and think it's less urgent.

Wouldn't it be a good test of the backcasting to compare model results with the latest ice loss data ?

Here is some interesting information from 2013 -- the Guardian --

http://www.theguardian.com/environment/earth-insight/2013/dec/09/us-navy-arctic-sea-ice-2016-melt

The project, based out of the US Naval Postgraduate School's Department of Oceanography, uses complex modelling techniques that make its projections more accurate than others.

sorry for the Long copy and paste.

I'm familiar with that - the US navy has a more accurate model. Is it more accurate or does it agree with the CPDN modelling ?

This needs to be taken in context.

The models used have been written over many years, by many people, at the UK Met Office, for running on several generations of supercomputers.

These people, and those providing the data sets that we run, (and getting the results that we return), are professionals, and are always looking at and for research results in the climate field.
So they'll be well aware of what your post refers to. And a lot more that doesn't make it into the popular press.

As for what data is included in different runs of our modelling, that's up to the researchers running each experiment. And if you watch the files being down loaded onto your computer, you can see some of the data ideas (for want of a better word), that are going to be used.

And the models are getting more sophisticated, as computers available to the public get more powerful.
e.g. You'll notice from the Server Status page that some use the MOSES II land scheme, and some also use TRIFFID.
The earlier models used MOSES, the original scheme. These II versions are using the latest, more detailed descriptions.
(MOSES and TRIFFID are descriptor files for various land use. e.g. vegetation, large bodies of water, high snow forming mountains, etc.)

If you look at this old one of mine under Perturbed Parameters, you can see that it took into account Sea ice, and also the file in which that was contained.
Others over the years have labels to do with ice fall.

As for what ANY military group is using, I'd prefer not to comment. I don't want people with fedoras, dark glasses, and turned up collars coming around and asking me what I'm up to.

Hi Les, Iain, Napoleon ... thank you for this information, excellent posts.

I don't want people with fedoras, dark glasses, and turned up collars coming around and asking me what I'm up to.

I don't the the Fedoras are standard issue anymore, unless you live in a Noir film.

---

Click Here to see My Detailed BOINC Stats

And it seems in the northern hemisphere, ice might be "more sensitive to changes in summer melting than it is to winter cooling".

New measurements from ESA�s CryoSat Satellite show that the volume of Arctic sea ice increased following the unusually cool summer of 2013, suggesting that ice in the northern hemisphere is more sensitive to changes in summer melting than it is to winter cooling.

http://scitechdaily.com/cryosat-satellite-shows-increased-volume-of-arctic-sea-ice/

---

Professor Desty Nova
Researching Karma the Hard Way

Hi Les, Iain, Napoleon ... thank you for this information, excellent posts.

Aye

This needs to be taken in context.

The models used have been written over many years, by many people, at the UK Met Office, for running on several generations of supercomputers.

These people, and those providing the data sets that we run, (and getting the results that we return), are professionals, and are always looking at and for research results in the climate field.
So they'll be well aware of what your post refers to. And a lot more that doesn't make it into the popular press.

As for what data is included in different runs of our modelling, that's up to the researchers running each experiment. And if you watch the files being down loaded onto your computer, you can see some of the data ideas (for want of a better word), that are going to be used.

And the models are getting more sophisticated, as computers available to the public get more powerful.
e.g. You'll notice from the Server Status page that some use the MOSES II land scheme, and some also use TRIFFID.
The earlier models used MOSES, the original scheme. These II versions are using the latest, more detailed descriptions.
(MOSES and TRIFFID are descriptor files for various land use. e.g. vegetation, large bodies of water, high snow forming mountains, etc.)

If you look at this old one of mine under Perturbed Parameters, you can see that it took into account Sea ice, and also the file in which that was contained.
Others over the years have labels to do with ice fall.

As for what ANY military group is using, I'd prefer not to comment. I don't want people with fedoras, dark glasses, and turned up collars coming around and asking me what I'm up to.

OK, but are the CPDN models like whatever it is the IPCC is using ?
A lot of scientists are saying things like this -

https://www.washingtonpost.com/news/energy-environment/wp/2015/07/23/controversial-sea-level-rise-paper-is-now-published-online/

�There is no doubt that the sea level rise, within the IPCC, is a very conservative number,� says Greg Holland, a climate and hurricane researcher at the National Center for Atmospheric Research, who has also reviewed the Hansen study. �So the truth lies somewhere between IPCC and Jim.�

I've asked a couple of well qualified scientists about this and they also say the IPCC is too conservative on sea level.

So I wonder what the score is there.

Here's a wee bit more about this, from the latest by James Hansen

http://www.huffingtonpost.com/dr-james-hansen/multi-meter-sea-level-rise-is-an-issue-for-todays-public_b_7875828.html

...which to me says that ice modelling is something tricky that hasn't been mastered yet

Says,

In contrast, we show in a prior paper and our new paper that ice sheet models are far too sluggish compared with the magnitude and speed of sea level changes in the paleoclimate record. This is not surprising, given the primitive state of ice sheet modeling.

So would the CPDN simulations concur with this - do their ice results match with the paleoclimate record ?

The IPCC reports are conservative because the representatives of a lot of the governments insist on "watering it down". Otherwise they can end up in strife from big business.

The originator of the University of Oxford's interest in climate, Prof Myles R. Allen (People) does, apparently, have input to IPCC reports.

A lot of the problem with ice simulation is due to the small number of polar monitoring stations, and thus the small amount of data available from there, compared to the rest of the world. Thus computer simulations of polar ice is nowhere near as good or as accurate as for the more populated parts of the planet.

Give it another 10 years, and then re-visit the subject. :)

Give it another 10 years, and then re-visit the subject. :)

I think that'll be a visit to an expanse of open water by then.