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2 hours ago, BLAST FROM THE PAST said:

Hi BFTP, I really wanted to avoid getting into this rather heated or shall I say "passionate" exchange of views. I strongly believe in a well considered, evidence based and respectful debate but this does seem to have degenerated intos omething  rather less savoury. I know that you have a good knowledge, especially on solar activity and impacts and that you have formed your own views on climate change over a period of time. I should say that just on that point, I take a very balanced approach towards climate change and global warming. Almost everyone agrees that it is happening but the debate is even more polarised than Brexit is and it's a worldwide issue. It's the degree of human influences vs natural variability that is causing the most disagreement. The politics in all this has gone off the scale.  Well respected scientists are often misquoted, other scientists' are sometimes controlled by their employers who have vested interests at one end of the debate or the other - the paymaster rules! There are still plenty of "independents" out there and I wish all scientists could go back to some of their golden rules, which is to always keep an open mind, challenge existing theories and search for the real evidence. Then the media and other influential people get involved and put their slant on things. Fake news, a lot of hype, misleading or exaggerated statistics and false claims are made from both sides and the divide becomes even greater. Then the instant worldwide exposure through all the social (or unsocial!) media channels expands on these news stories and reports and any inaccuracies become highly magnified with many innocent members of the general public taking much of it as factual when very often it is not. The more the dramatic and sensational the news story or report is the more likely it is that the facts becoming distorted.  

I "passionately" believe in balance and that many of us on these weather forums with varying degrees of meteorological and climatological knowledge and experience should be highly responsible about all of this.  We can pool our knowledge on threads like this (re Antarctica) or on other specialist thread by analysing reports, news stories and statistics with completely open minds - not allowing our personal views to interfere.  That way we have half a chance of sifting out the facts from the fiction to far better understand exactly what is going on.  What is the rate of change; what is the degree of human influence; what are the longer term cycles that effect natural variability; how different are current conditions to those historically (recent and long term past); how do all these interact; what are the short, medium and long term influences and impacts;  what can be done to avoid the worst of them (eg: I've heard recently that technology may be developed to harness the methane as it escapes from thawing tundra and permafrost regions - just one of many sensible solutions which would also reduce atmospheric pollution or avoid a further increase - better to use it as fuel and break down this highly toxic gas into far less toxic ones).

Now turning to current discussions @BornFromTheVoid is right that an awful lot of inaccurate claims are being made on here but i can see how a misunderstanding has developed over this report. I've been following NASA's work for some time. If one reads the full article in that report you will see that the first part does refer to NASA's main research into Antarctica volcanoes but they do NOT claim that this will lead to a massive melting of land ice. They explain how some of the fairly recently discovered subterranean lakes (during the last 5 years or so) are quite likely to have been formed by volcanism.  Remember that some of the vast lakes have been discovered further east and more inland too and the biggest ones which contain liquid water are sometimes over 3 miles below the thickest parts of the ice sheet and may be over 40 million year old. NASA are referring to near the western Antarctica coastline where some "net" ice loss has occurred in recent years. They say that the ice sheet/shelves there are becoming more unstable and that volcanism "might" be a contributory factor (it's useful to read some of their earlier reports on this to put it into perspective). They suggest that all this needs to be explored further. Note that the report is on their news media site and it is the second part that they refer to where the claim is being "suggested" but they are referencing the report by scientists Helene Seroussi and Eric Ivins who have done research into this and also into Greenland's ice cap for at least 6 years and they've written many reports.on this subject. (always a good idea to check out the authors).  NASA reference their fascinating paper: "Influence of a West Antarctic mantle plume on ice sheet basal conditions," which you'll find was actually published over a year ago (on 1st August 2017) and built on their earlier research - so nothing new about this latest news - just that social media seem to have been quite late into jumping on the band wagon and bringing it into the heart of the climate change debate. In any event, there is actually a reasonable degree of balance in the paper.

Volcanism itself is "mostly" naturally occurring but how it interacts with the more unstable western Antarctic ice sheet certainly does need to be studied and that's exactly what much of the research going on down there is aimed at. Frankly, it is far too early to jump to any conclusions and definitely not to infer that 2+2=5 (or more). The paper was published in the Journal of Geophysical Research: Solid Earth.  The authors/scientists work for several institutions and are indeed currently contracted to JPL (Jet Propulsion Laboratory) which is sponsored by NASA. . 

It should be noted that the "very slight" net melting in western Antarctica does "seem" to be more or less compensated by the increased snowfall, particularly in the drier interior and much of the east. This additional snowfall, is speeding up the ice cycle. The main ice sheet and small glaciers are indeed moving more quickly. Ice shelves breaking off into the sea do make for sensational news headlines but this is all part of the process.  What matters is the "net" ice amount on the whole continent. There are some conflicting reports on this and we must get at the truth.  With further global temp rises (if/as they happen) there is likely to be far greater snowfall. The Antarctica ice equilibrium may well be maintained for many years if not centuries but "if" other global ice retreat and loss does continue and worldwide temps continue to rise, all that increased snowfall in Antarctica might do (and perhaps also Greenland to a lesser extent - see my long post on the good news story there for 2018 on the Arctic Ice and Stats thread) is slow down the overall process to some extent. The other thing to bear in mind is that the behaviour of a mountain glacier or snowfield and how it reacts to volcanism is on a very minor scale compared to a vast ice sheet. Far more research is needed and we can track some of this on this thread but let's not argue about it all, instead let's examine the facts. David :) .  

Edited by Guest
correct typos

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2 hours ago, BornFromTheVoid said:

They're not causing a warming trend or mass loss trends. They're contributing to the flow rate, as I mentioned.

From the article:

"Although the heat source isn't a new or increasing threat to the West Antarctic ice sheet, it may help explain why the ice sheet collapsed rapidly in an earlier era of rapid climate change, and why it is so unstable today.

The stability of an ice sheet is closely related to how much water lubricates it from below, allowing glaciers to slide more easily."

Yes indeed, ‘it’ may explain why the ice sheet collapsed rapidly (I personally suspect it has more than suggested at this stage) and volcanic activity increases as we enter deep minimas.  We move on and I concur with David.....over and out from this thread for a while.

 

BFTP

Edited by BLAST FROM THE PAST

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1 hour ago, Bring Back1962-63 said:

Hi BFTP, I really wanted to avoid getting into this rather heated or shall I say "passionate" exchange of views. I strongly believe in a well considered, evidence based and respectful debate but this does seem to have degenerated intos omething  rather less savoury. I know that you have a good knowledge, especially on solar activity and impacts and that you have formed your own views on climate change over a period of time. I should say that just on that point, I take a very balanced approach towards climate change and global warming. Almost everyone agrees that it is happening but the debate is even more polarised than Brexit is and it's a worldwide issue. It's the degree of human influences vs natural variability that is causing the most disagreement. The politics in all this has gone off the scale.  Well respected scientists are often misquoted, other scientists' are sometimes controlled by their employers who have vested interests at one end of the debate or the other - the paymaster rules! There are still plenty of "independents" out there and I wish all scientists could go back to some of their golden rules, which is to always keep an open mind, challenge existing theories and search for the real evidence. Then the media and other influential people get involved and put their slant on things. Fake news, a lot of hype, misleading or exaggerated statistics and false claims are made from both sides and the divide becomes even greater. Then the instant worldwide exposure through all the social (or unsocial!) media channels expands on these news stories and reports and any inaccuracies become highly magnified with many innocent members of the general public taking much of it as factual when very often it is not. The more the dramatic and sensational the news story or report is the more likely it is that the facts becoming distorted.  

I "passionately" believe in balance and that many of us on these weather forums with varying degrees of meteorological and climatological knowledge and experience should be highly responsible about all of this.  We can pool our knowledge on threads like this (re Antarctica) or on other specialist thread by analysing reports, news stories and statistics with completely open minds - not allowing our personal views to interfere.  That way we have half a chance of sifting out the facts from the fiction to far better understand exactly what is going on.  What is the rate of change; what is the degree of human influence; what are the longer term cycles that effect natural variability; how different are current conditions to those historically (recent and long term past); how do all these interact; what are the short, medium and long term influences and impacts;  what can be done to avoid the worst of them (eg: I've heard recently that technology may be developed to harness the methane as it escapes from thawing tundra and permafrost regions - just one of many sensible solutions which would also reduce atmospheric pollution or avoid a further increase - better to use it as fuel and break down this highly toxic gas into far less toxic ones).

Now turning to current discussions @BornFromTheVoid is right that an awful lot of inaccurate claims are being made on here but i can see how a misunderstanding has developed over this report. I've been following NASA's work for some time. If one reads the full article in that report you will see that the first part does refer to NASA's main research into Antarctica volcanoes but they do NOT claim that this will lead to a massive melting of land ice. They explain how some of the fairly recently discovered subterranean lakes (during the last 5 years or so) are quite likely to have been formed by volcanism.  Remember that some of the vast lakes have been discovered further east and more inland too and the biggest ones which contain liquid water are sometimes over 3 miles below the thickest parts of the ice sheet and may be over 40 million year old. NASA are referring to near the western Antarctica coastline where some "net" ice loss has occurred in recent years. They say that the ice sheet/shelves there are becoming more unstable and that volcanism "might" be a contributory factor (it's useful to read some of their earlier reports on this to put it into perspective). They suggest that all this needs to be explored further. Note that the report is on their news media site and it is the second part that they refer to where the claim is being "suggested" but they are referencing the report by scientists Helene Seroussi and Eric Ivins who have done research into this and also into Greenland's ice cap for at least 6 years and they've written many reports.on this subject. (always a good idea to check out the authors).  NASA reference their fascinating paper: "Influence of a West Antarctic mantle plume on ice sheet basal conditions," which you'll find was actually published over a year ago (on 1st August 2017) and built on their earlier research - so nothing new about this latest news - just that social media seem to have been quite late into jumping on the band wagon and bringing it into the heart of the climate change debate. In any event, there is actually a reasonable degree of balance in the paper.

Volcanism itself is "mostly" naturally occurring but how it interacts with the more unstable western Antarctic ice sheet certainly does need to be studied and that's exactly what much of the research going on down there is aimed at. Frankly, it is far too early to jump to any conclusions and definitely not to infer that 2+2=5 (or more). The paper was published in the Journal of Geophysical Research: Solid Earth.  The authors/scientists work for several institutions and are indeed currently contracted to JPL (Jet Propulsion Laboratory) which is sponsored by NASA. . 

It should be noted that the "very slight" net melting in western Antarctica does "seem" to be more or less compensated by the increased snowfall, particularly in the drier interior and much of the east. This additional snowfall, is speeding up the ice cycle. The main ice sheet and small glaciers are indeed moving more quickly. Ice shelves breaking off into the sea do make for sensational news headlines but this is all part of the process.  What matters is the "net" ice amount on the whole continent. There are some conflicting reports on this and we must get at the truth.  With further global temp rises (if/as they happen) there is likely to be far greater snowfall. The Antarctica ice equilibrium may well be maintained for many years if not centuries but "if" other global ice retreat and loss does continue and worldwide temps continue to rise, all that increased snowfall in Antarctica might do (and perhaps also Greenland to a lesser extent - see my long post on the good news story there for 2018 on the Arctic Ice and Stats thread) is slow down the overall process to some extent. The other thing to bear in mind is that the behaviour of a mountain glacier or snowfield and how it reacts to volcanism is on a very minor scale compared to a vast ice sheet. Far more research is needed and we can track some of this on this thread but let's not argue about it all, instead let's examine the facts. David :) .  

Super post and its great to see you back on the forum again. I loved reading your posts last winter 😊

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The process that really does help explain the rapid ice losses across West Antarctica in past warmer eras can be seen in action in some of the ice terminating glaciers in Greenland and has nothing to do with volcanism!

Gravity is the enemy not temperature! The mechanical properties of ice and the impacts of gravity is all that is needed to see an unstoppable collapse of the ice cover across west Antarctica.

In Greenland we have seen that ice can no longer support itself when it is over 100m high. Anyone wishing to check the details needs to google 'Ice Cliff Fracturing' and then have a look at the channel between west and East Antarctica.

The fact that the ice shelf is now over the last pinning point before we enter the rapid retreat that ice cliff fracturing will facilitate should be what folk are concentrating on not the role of mantle heat on the base of the ice sheet!

We are at a point of the first domino being about to fall in a domino run that will see sea levels put on multiple inches over a decade and folk whitter about volcanic heat!!!

 

Edited by Gray-Wolf

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Dave's suggestion of using methane as a fuel raises yet another question, I think:

The oxidation of a single molecule of CH4 produces two molecules of H2O, I think - so my question is: are two molecules of water more or less dangerous (as GHGs) than one molecule of methane?

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Water is a major green house gas but the feedback mechanisms are poorly understand apparently. 

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Will we set another record low this year?

 

Will it be the first sub 2 million minimum?

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21 minutes ago, parrotingfantasist said:

Falling real sharp since the tenth or so......

snow.PNG

Have you got a better graph?

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32 minutes ago, Rambo said:

Have you got a better graph?

A few options.
If you select the Antarctica option on the right, you can then toggle through the different options underneath the graph here: https:/ ads.nipr.ac.jp/vishop/#/extent/&time=2018-12-21 00:00:00

Similarly, select the Antarctica option on the top left, then you can toggle through the various years on the right hand side here: https://nsidc.org/arcticseaicenews/charctic-interactive-sea-ice-graph/

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2 hours ago, Rambo said:

Have you got a better graph?

 It wasn't the best was in a rush. Meant to show the transition into what seems to be a free fall now.

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Cheers all. 

More or less on par, but now a touch under 1979 (would it of been as accurate then?). I personally think free-fall might be a little strong though (for the moment at least)

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A scary rate of decline recently, which has just edged ahead of 2016 and 1979 as the lowest Antarctic sea ice extent for the time of year on record.  Anomalously high melting on both sides of West Antarctica appears to be to blame, with large areas of open water where we would normally have ice.  Around the Antarctic Peninsual and off East Antarctica the sea ice extent is near average.

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I think the scary reduction in compaction in Weddell points to us seeing a record low this year?

Since 2014 this would be the 3rd record low.

Something really changed in 2014! ( though not early enough to bring that years max to a record low but did show a 2 million 'float off' that bulked out extent/area prior to the collapse as the southern ocean took the 'float off' ice!)

But this is 'sea ice' and not our main concern in Antarctica ( though it does provide some level of stability to the shelfs over winter by damping out Southern Ocean swells.

Lessen that 'damping' over southern winter and we will see the shelves take a battering and some are a point we do not need to see retreating as it will be unstoppable ice cliff fracture that takes over their demise and not the usual slow 'creep and calve'

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Four decades of Antarctic Ice Sheet mass balance from 1979–2017
We evaluate the state of the mass balance of the Antarctic Ice Sheet over the last four decades using a comprehensive, precise satellite record and output products from a regional atmospheric climate model to document its impact on sea-level rise. The mass loss is dominated by enhanced glacier flow in areas closest to warm, salty, subsurface circumpolar deep water, including East Antarctica, which has been a major contributor over the entire period. The same sectors are likely to dominate sea-level rise from Antarctica in decades to come as enhanced polar westerlies push more circumpolar deep water toward the glaciers.

https://www.pnas.org/content/early/2019/01/08/1812883116

The take away graphs from the paper a below, with the cumulative surface mass balance shown in blue, the cumulative ice discharge in red, and cumulative mass loss in purple

F3.large.jpg?width=800&height=600&carous

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Scientists have discovered a giant cavity at the bottom of a disintegrating glacier in Antarctica, sparking concerns that the ice sheet is melting more rapidly than expected.

Researchers working as part of a Nasa-led study found the cavern, which they said was 300 metres tall and two-thirds the size of Manhattan, at the bottom of the massive Thwaites glacier.

https://www.theguardian.com/environment/2019/feb/07/cavity-two-thirds-the-size-of-manhattan-discovered-under-antarctic-glacier

 

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6 hours ago, Barking_Mad said:

 

 

Thwaites and Pine Island are both a critical points in their evolution with the next retreat placing them into rapid decline as they slip off the last 'lip' and into the basin behind.

This will then lead to 'ice cliff failure' becoming the major way ice will be lost ( like some of the Greenland ocean terminating glaciers are now seeing?)

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We know the last time we saw global temps and GHG's at these levels W.A.I.S. was absent.

This was one of eight absences of the ice over the past 2.5 million years and its loss appears to warm the Arctic;

https://www.newscientist.com/article/dn21959-loss-of-antarctic-ice-could-trigger-super-interglacial/

Or was it the warming of the Arctic that lead to the loss of W.A.I.S............ can the tail wag the dog?

 

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Gray-Wolf, I think we will be very lucky if Antarctic Ice Loss and Arctic Ice "only" cause a Super-Interglacial.  I fear more likely we are gonna end up in a full blown greenhouse era.  We are already on track to be warmer than at least 4C above the global 1750 average.  Even the Super-Interglacials of the Quaternary were only 1.5C-2C above the global 1750 average.

I also think there could be more than sea level rise involved in the pole to pole melt connection.  Loss of most if not all of Antarctic Ice would reduce or even eliminate Antarctic Bottom Water production in the Southern Ocean.  With less AABW or no even no AABW in the North Atlantic Ocean, North Atlantic Deep Water production would increase bigtime which in turn would beef up the warm Gulf Stream current.  This would cause rapid warming and deglaciation of both Greenland and the Arctic Sea Ice.

Edited by Lettucing Gutted

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I think the West of Antarctica goes away real quick and easy when the planet warms?

The same with 2/3rds of Greenland?

These areas must be so finely balanced that any concerted push tips the balance in that forcings favour?

I think we have started to put a concerted 'push' into our warming now with lots of the initial 'climate inertia' overcome ( including the orbital forcing for cooling across the far north?).

We appear a little late to the Party but now we understand the mechanics of 'ice cliff failure' a little better it becomes clear how we can , on a decadal speed, massively impact the land ice of West antarctica and Greenland.

We are told that current warming and GHG forcings are comparable with 125,000 yrs ago and then West Antarctica was ice free and 2/3rds of Greenland likewise.

All that matters now is how quickly we arrive at that point?

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Posted (edited)

 

Edited by knocker

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https://phys.org/news/2017-05-height-antarctica-slower-arctic.html

I happened across this article yesterday from a couple of years ago. It probably got shared on here but in case it wasn't, here's a link.


My overall impression is that Antarctica may be more of a 'dam burst' style event if and when the regional temperatures reach some critical threshold. The ice sheet surface starts to lose significant amounts of height, surface and near-surface temps increase accordingly, and losses accelerate in a vicious positive feedback.

I wonder, though, if the increasing depth of atmosphere, along with higher temperatures, would before long facilitate an increase in snowfall sufficient to counterbalance the temperature-driven losses? Depends how the relationship with surface insolation works out for ice sheets on a large continent rather than sea ice on an ocean (we know that added snow cover doesn't really help the Arctic sea ice in the long run; sure it may preserve more of it for one summer, but lost thickening during the freezing season offsets this).

This may become one of the hottest topics of scientific debate in some 50-200 years time (depending on which projections you look at).


While the bulk of Antarctica remains resiliently cold instead, increasing thermal gradients may mean that the Southern Ocean becomes even stormier than it already infamously is. What a thought!

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Hi Singularity!

What you describe is 'saddle and lobe' melt which is how we lost the great ice sheets at the end of the last ice age. Ice height drops it into the active melt zone but that accelerated melt leads to Ice Cliff Instability so gravity then crashes ice from the higher regions into the ever deepening valleys below. If this means ice ending in the ocean then melt will be faster and more assured but will also add to the cold water cap to the surface funnelling warmer,saltier ocean waters to the bases of ice shelf/glaciers speeding their demise.

As the Andean glaciers melt back they are revealing the land surface , with its vegetation, that was covered the year that the ice did not melt that summer so that glaciation can be tracked back to one year. If glaciation can happen so swiftly I'd be surprised if melt events can't also be so swift?

In our hemisphere the loss of snow patches in Alaska/N.Canada, and the retreat of year round ice cover in SW Greenland, surely shows us our direction of travel and, since 2014 , we see matched losses in the South with sea ice now battling for record lows each year. 

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