East Antarctica glacial stronghold melting as seas warm
Nasa detects ice retreat probably linked to ocean changes in region once thought stable
Damian Carrington Environment editor
Tue 11 Dec 2018
The Totten glacier, East Antarctica. Photograph: Esmee van Wijk/Australian Antarctic Division
A group of glaciers spanning an eighth of the East Antarctica coastline are being melted by the warming seas, scientists have discovered.
This Antarctic region stores a vast amount of ice, which, if lost, would in the long-term raise global sea level by tens of metres and drown coastal settlements around the world.
Freezing temperatures meant the East Antarctica region was until recently considered largely stable but the research indicates that the area is being affected by climate change.
To the east of Totten, in Vincennes Bay, the height of the glaciers has fallen by about three metres in total since 2008, before which no loss had been recorded.
To the west of Totten, in Wilkes Land, the rate of height loss has doubled since 2009, with glaciers losing height by about two and a half metres to date.
The data comes from detailed maps of ice movement speed and height created by Nasa from satellite information.
Ocean heat drives rapid basal melt of the Totten Ice Shelf
Stephen Rich Rintoul1,2,*, Alessandro Silvano2,3, Beatriz Pena-Molino1, Esmee van Wijk2, Mark Rosenberg1, Jamin Stevens Greenbaum4 and Donald D. Blankenship4
Antarctic Climate and Ecosystems Cooperative Research Centre, University of Tasmania, Hobart, Tasmania, Australia.
Commonwealth Scientific and Industrial Research Organization Oceans and Atmosphere, Hobart, Tasmania, Australia.
Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, Tasmania, Australia.
Institute for Geophysics, University of Texas at Austin, Austin, TX 78758, USA.
Mass loss from the West Antarctic ice shelves and glaciers has been linked to basal melt by ocean heat flux. The Totten Ice Shelf in East Antarctica, which buttresses a marine-based ice sheet with a volume equivalent to at least 3.5 m of global sea-level rise, also experiences rapid basal melt, but the role of ocean forcing was not known because of a lack of observations near the ice shelf. Observations from the Totten calving front confirm that (0.22 ± 0.07) × 106m3 s−1 of warm water enters the cavity through a newly discovered deep channel. The ocean heat transport into the cavity is sufficient to support the large basal melt rates inferred from glaciological observations. Change in ocean heat flux is a plausible physical mechanism to explain past and projected changes in this sector of the East Antarctic Ice Sheet and its contribution to sea level.
INTRODUCTION
Ice shelves form where the Antarctic Ice Sheet reaches the ocean and begins to float. Back stress produced by the interaction of the floating ice shelf with side walls and topographic rises buttresses the grounded ice sheet and inhibits the flow of ice into the ocean (1). The thinning or weakening of ice shelves reduces the back stress, increasing the discharge of grounded ice into the ocean and raising sea levels. The thinning of Antarctic ice shelves has been attributed to basal melt by ocean heat flux (2, 3), with the most rapid thinning, grounding line retreat, and acceleration of glacial flow observed in the Bellingshausen Sea and the Amundsen Sea (3, 4). Much of the ice sheet in that sector of Antarctica rests on bedrock below sea level that deepens upstream, a potentially unstable configuration that may result in rapid glacial retreat and mass loss to the ocean (5, 6). Models and observations suggest that increased ocean heat flux may have already initiated the unstable retreat of some West Antarctic glaciers (4, 7, 8). Therefore, the future evolution of the Antarctic Ice Sheet is tightly linked to change in the surrounding ocean.
Observations from the Totten calving front confirm that (0.22 ± 0.07) × 106m3 s−1 of warm water enters the cavity through a newly discovered deep channel.
What was inferred:
The ocean heat transport into the cavity is sufficient to support the large basal melt rates inferred from glaciological observations.
What was presumed to be plausible:
Change in ocean heat flux is a plausible physical mechanism to explain past and projected changes in this sector of the East Antarctic Ice Sheet and its contribution to sea level.
What was not in the paper:
The vast Totten glacier was known to be retreating but the new analysis shows that nearby glaciers in the East Antarctica area are also losing ice.
Ice shelves are not glaciers. The “vast Totten glacier” has not been known to be retreating. One small portion of the “vast Totten glacier” has been retreating.
Totten Glacier
Abstract
Totten Glacier has the largest ice discharge in East Antarctica and a basin grounded mostly below sea level. Satellite altimetry data have revealed ice thinning in areas of fast flow. Here we present a time series of ice velocity measurements spanning from 1989 to 2015 using Landsat and interferometric synthetic-aperture radar data, combined with ice thickness from Operation IceBridge, and surface mass balance from Regional Atmospheric Climate Model. We find that the glacier speed exceeded its balance speed in 1989 – 1996, slowed down by 11 ± 12% in 2000 to bring its ice flux in balance with accumulation (65 ± 4 Gt/yr), then accelerated by 18 ± 3% until 2007, and remained constant thereafter. The average ice mass loss (7 ± 2 Gt/yr) is dominated by ice dynamics (73%). Its acceleration (0.6 ± 0.3 Gt/yr2) is dominated by surface mass balance (80%). Ice velocity apparently increased when ocean temperature was warmer, which suggests a linkage between ice dynamics and ocean temperature.
1. Introduction
Totten Glacier has the largest ice discharge in East Antarctica. Its ice flux into the southern ocean was about 71 ± 3 Gt/yr in 2003 – 2008 [Rignot et al., 2013]. Most of its drainage basin is grounded well below sea level [Young et al., 2011]. If all ice contained in its basin were to melt into the ocean, the glacier would raise global sea level by 3.9 m [Li et al., 2015]. Oceanographic data are few in this part of Antarctica, but existing data indicate the presence of warm modified Circumpolar Deep Water (mCDW) at about 0°C below 500 m depth on the continental shelf [Bindoff et al., 2000; Williams et al., 2011]. The bathymetry beneath and in front of its 130 km long ice shelf holds potential pathways for intrusion of this mCDW into the ice shelf cavity [Greenbaum et al., 2015]. This would explain the high area-average ice shelf melt rate recorded on Totten Ice Shelf (10.5 ± 0.7 m/yr) compared to other ice shelves in East Antarctica [Rignot et al., 2013].
Examination of changes in ice surface elevation over time indicates ice shelf thinning in 2003 – 2008 but no significant long-term trend for the time period 1994 – 2012 [Paolo et al., 2015]. In contrast, the satellite radar altimetry record on land indicates that ice thinning took place in areas of fast flow, with little to no thinning in the surrounding, slower-moving areas [Zwally et al., 2005; Davis et al., 2005; Shepherd and Wingham, 2007; Flament and Rémy, 2012; Horwath et al., 2012; McMillan et al., 2014]. Ice thinning at the grounding line of the fastest portion of Totten Glacier averaged 1.7 ± 0.2 m/yr for the period 2003 – 2008 with ICESat [Pritchard et al., 2009, 2012] and 0.5 ± 0.01 m/yr with Cryosat-2 for 2010 – 2013 [McMillan et al., 2014]. Time-variable gravvity data from the Gravity Recovery and Climate Experiment (GRACE) for the time period 2003 – 2013 suggest an accelerating mass loss for Totten, Moscow University, and Frost combined [Velicogna et al., 2014; Williams et al., 2014]. Comparison of the mass loss derived from GRACE with time series of surface mass balance (SMB) anomalies from the Regional Atmospheric Climate Model (RACMO2) [Lenaerts et al., 2012] over the same time period suggests that only 40% of the signal is explained by SMB [Velicogna et al., 2014].
A recent analysis showed that the glacier grounding line retreated by 1 to 3 km between 1996 and 2013, corresponding to an average ice thinning rate of 0.7 ± 0.1 m/yr [Li et al., 2015]. This magnitude thinning is consistent with the altimetry record and suggests that ice has been flowing faster than the speed required to maintain a state of mass balance with snowfall in the interior region.
[…]
5. Conclusions
We assembled a 26 year long time series of ice velocity measurements on Totten Glacier to conclude that the glacier speed has fluctuated up to 18% during the time period, with low values around 2000, high values prior to 1996 and after 2002. In the last 10 years, the glacier has maintained a relatively steady speed but has been flowing above equilibrium conditions. The glacier has been losing mass at a rate of 6.8 ± 2.4 Gt/yr or 10% of the total flux on average for the past 26 years. The main loss is caused by the speedup of the glacier along its main flow. Our results also suggest that the glacier may be strongly sensitive to ocean temperature. More detailed studies are needed to quantify the impact of ocean temperature on ice dynamics in this important sector of East Antarctica.
Figure 1 from Li et al., 2016. “(a) Ice velocity magnitude and (b) direction of Totten Glacier, East Antarctica, color coded on a logarithmic scale and overlaid on MODIS Mosaic of Antarctica image [Scambos et al., 2007] using ALOS PALSAR data from 2006 to 2010 and 2011 TDX/TSX, 2013 TDX/TSX, CSK, and Landsat-8 data. The grounding line (GL) from 2013 is solid white. Flux gates are solid yellow (GL) and orange (along Operation IceBridge (OIB) ground tracks). Green boxes A and B delineate the area used to generate the velocity time series (Figure 2a). Brown box is the map outline of Figures 1b and 3. BEDMAP2 surface elevation [Fretwell et al., 2013] contours are plotted at 300 m intervals.Figure 2 from Li et al., 2016. “Time series of (a) ice velocity, (b) ice discharge (D) and surface mass balance (SMB), (c) subsurface ocean potential temperature (450–600 m depth), and (d) cumulative mass anomalies on Totten Glacier, East Antarctica. Figure 2a shows velocity change at the grounding line (box A in Figure 1) and at the east tributary (box B). Error bars for the bottom time series are the same as the top one. Red dots in Figure 2b show average potential temperature for each velocity data epoch in Figure 2a. Grey dashed lines are fitted using a piecewise linear regression. SMB values in Figure 2c are smoothed with a 12 month running filter. The total mass anomalies (black) in Figure 2d are partitioned between the anomalies in SMB (red) and in ice discharge (D, in blue).”Figure 3 from Li et al., 2016. “Change in flow speed from year (a) 2000 to 2007, (b) 2007 to 2013, and (c) 2009 to 2010 on Totten Glacier, East Antarctica, overlaid on a MODIS Mosaic of Antarctica [Scambos et al., 2007]. Grounding line from Li et al. [2015] is in black.”
Key points about Totten Glacier:
It has the largest discharge of any Antarctic outlet glacier. It already had this when they started measuring glaciers in Antarctica.
Surface mass balance exhibits very little in the way of a coherent trend,
Thinning exhibits “no significant long-term trend for the time period 1994 – 2012.”
“Ice thinning took place in areas of fast flow, with little to no thinning in the surrounding, slower-moving areas.”
Ice velocity in the discharge area has widely fluctuated.
“The glacier grounding line retreated by 1 to 3 km between 1996 and 2013.”
“If all ice contained in its basin were to melt into the ocean, the glacier would raise global sea level by 3.9 m.”
“The glacier has been losing mass at a rate of 6.8 ± 2.4 Gt/yr… on average for the past 26 years.”
Is 6.8 Gt/yr significant?
We can calculate the volume of water required to raise global sea levels by 1 mm:
Volume = area x height
Area = 3.618 x 108 km2
Height = 10-6 km (1 mm)
Volume (km3) = (3.618 x 108 km2 ) x (10-6 km) = 3.618 x 102 km3 = 361.8 km3 water.
We can convert km3 of water to Gt of water as we did above; 1 km3 water = 1 Gt water. In the same way, 1 Gt of ice = 1 km3 water. So, 361.8 Gt of ice will raise global sea levels by 1 mm. 361.8 Gt of ice is equivalent to 394.67 km3 ice.
If we took our 458.30 Gt of ice (as calculated above), then we could calculate the global sea level equivalent by:
SLE (mm) = mass of ice (Gt) x (1 / 361.8)
SLE = 458.30 x (1 / 361.8)
SLE = 1.27 mm
However, we should note that some of the world’s glaciers have parts that are below sea level. This ice will not affect sea level if it melted. The volume of glacier ice below the surface of the ocean should therefore be subtracted from the total volume of glaciers and ice caps when calculating sea level equivalents [15].
If “most of its drainage basin is grounded well below sea level,” then “if all ice contained in its basin were to melt into the ocean, the glacier would raise global sea level by” less than 3.9 m. But this number enables us to calculate the mass of Totten Glacier.
If 361.8 Gt of ice melt will raise sea level by 1 mm, the ice mass of Totten Glacier is:
368.1 Gt/mm x 3,900 mm = 1,411,020 Gt
The current ice mass is around 1.4 million Gt.
6.8 Gt ÷ 1,411,020 = 0.000005 = 0.0005%
According to Li et al., 2016, Totten Glacier has cumulative mass balance loss of about 180 Gt from 1988-2016.
180 Gt ÷ 1,411,020 = 0.0001 = 0.01%
99.99% of Totten glacier did not ablate from 1988-2016. At 6.8 Gt/yr, it would take 207,503 years for the melting of Totten Glacier to raise sea level by 3.9 m. So, one has to ask, “Why in the Hell did Li et al., 2016 mention this in their paper?” Yes, that was a rhetorical question.
Back to The Grauniad:
A group of glaciers spanning an eighth of the East Antarctica coastline are being melted by the warming seas, scientists have discovered.
This Antarctic region stores a vast amount of ice, which, if lost, would in the long-term raise global sea level by tens of metres and drown coastal settlements around the world.
The red areas on the Grauniad map are glacial discharge areas. These are areas of higher ice velocity. Although glaciers often move at a glacially slow pace, they are suppose to move.
A glacier is a persistent body of dense ice that is constantly moving under its own weight; it forms where the accumulation of snow exceeds its ablation (melting and sublimation) over many years, often centuries.
If all of the glaciers that feed the red areas on the map flowed into the ocean and melted, sea level would rise by 10’s of meters… “If ifs and buts were candy and nuts, we’d all have a Merry Christmas.” There’s no scenario by which all of this ice could melt and flow into the ocean… So, why even mention it in the article? Yes… another rhetorical question.
If the ice shelves supposedly buttressing these glaciers melted, sea level would barely notice.
However, the loss of these ice shelves would supposedly cause the glaciers to collapse into the sea. This is based entirely on models.
Abstract
[1] Reduction or loss of a restraining ice shelf will cause speed‐up of flow from contiguous ice streams, contributing to sea‐level rise, with greater changes from ice streams that are wider, have stickier beds, or have higher driving stress. Loss of buttressing offsetting half of the tendency for ice‐stream/ice‐shelf spreading for an ice stream similar to Pine Island Glacier, West Antarctica is modeled to contribute at least 1 mm of sea‐level rise over a few decades. These results come from a new, simple model that includes relevant stresses in a boundary‐layer formulation, and allows rapid estimation of ice‐shelf impacts for a wide range of configurations.
Scambos et al., 2004 ostensibly documented “a two‐ to six‐fold increase in centerline speed of four glaciers” after the collapse of the Larsen B ice shelf. However, this is on the Antarctic Peninsula and unlikely to be analogous the vast East Antarctic Ice Sheet, which has been stable since at least the Pliocene and likely to have been stable since at least the Mid-Miocene.
Conclusion
Antarctic glaciers aren’t doing anything now, that they haven’t been doing for the past 12,000 years.
The history of deglaciation of the West Antarctic Ice Sheet (WAIS) gives clues about its future. Southward grounding-line migration was dated past three locations in the Ross Sea Embayment. Results indicate that most recession occurred during the middle to late Holocene in the absence of substantial sea level or climate forcing. Current grounding-line retreat may reflect ongoing ice recession that has been under way since the early Holocene. If so, the WAIS could continue to retreat even in the absence of further external forcing…
Conway, H. et al, 1999. Past and Future Grounding-Line Retreat of the West Antarctic Ice Sheet. Science 8 October 1999: Vol. 286 no. 5438 pp. 280-283
Dupont, T. K., and R. B. Alley (2005), Assessment of the importance of ice‐shelf buttressing to ice‐sheet flow, Geophys. Res. Lett., 32, L04503, doi:10.1029/2004GL022024.
Li, X., E. Rignot, J. Mouginot, and B. Scheuchl (2016), Ice flow dynamics and mass loss of Totten Glacier, East Antarctica, from 1989 to 2015, Geophys. Res. Lett., 43, 6366 – 6373, doi:10.1002/2016GL069173.
Rintoul, Stephen & Silvano, Alessandro & Pena-Molino, Beatriz & van Wijk, Esmee & Rosenberg, Mark & Greenbaum, Jamin & D. Blankenship, Donald. (2016). Ocean heat drives rapid basal melt of the Totten Ice Shelf. Science Advances. 2. 10.1126/sciadv.1601610.
Scambos, T. A., J. A. Bohlander, C. A. Shuman, and P. Skvarca (2004), Glacier acceleration and thinning after ice shelf collapse in the Larsen B embayment, Antarctica, Geophys. Res. Lett., 31, L18402, doi:10.1029/2004GL020670.
Apparently, a significant proportion of its daily sales are to that other Progressive sinkhole, the BBC. Without that, actual sales to the public are much smaller.
Don’t worry – the paper may not be around much longer. The latest financial results of the Graun’s holding company have just come out. Worse than ever despite begging letters on the website for contributions.
It is wasn’t the left’s only proper newspaper, it would have disappeared long ago as so few buy it or advertise in it. There are limits as to how many times benefactors will be prepared to bail it out.
The Guardian is supported by the billion pound Scott Trust. They have managed to get losses down to around £20 million a year which means that the Guardian will probably keep going for ever. It’s a truly dreadful newspaper but some people like it. One thing about the Guardian is that its biases are plain for all to see.
Is there anything they do that doesn’t involve models? It’s like they are a bunch of children that never wanted to stop playing computer and actually grow up
I’m not a scientist but I thought direct observation was the foundation
Steven J Hill
December 13, 2018 1:27 pm
Of course it’s melting, was gone by 2013 per Al Gore, we are ice free now……Hurricanes are expected down there in 2019
Steven J Hill
December 13, 2018 1:28 pm
I am trying to figure out how we have ice on the ponds here in Ky and the poles are ice free?
All the article says is that the glaciers are being melted by the sea. Isn’t this always the case for ocean outlet glaciers? No mention of the interior land end being replenished with snow. And glaciers often advance faster for a few years and slower for a few. And, Antarctic ice mass has increased. So all in all, a disingenuous article.
Especially given it’s been cold for many, many years.
icisil
December 13, 2018 2:28 pm
“If the ice shelves supposedly buttressing these glaciers melted, sea level would barely notice.
However, the loss of these ice shelves would supposedly cause the glaciers to collapse into the sea. This is based entirely on models.”
How could glaciers continue to collapse when the collapsed ice cliff would act as a buttress against further collapse?
Clyde Spencer
December 13, 2018 2:30 pm
I can’t imagine floating sea ice offering a resistance to glaciers that is greater than the resistance encountered at bedrock by the glaciers. The key to this appears to be the sea ice that is grounded. That is, the sea ice is experiencing friction at the grounding line. Assuming, for the sake of argument, that the grounded sea ice were to break off and float away, there might be a temporary surge in the glacier. But, when the tongue of the glacier gets to the grounding line, I would expect it to come to a ‘screeching’ halt. The loss of the sea ice isn’t a “tipping point,” but rather, a new equilibrium.
I think the concept behind catastrophic ice collapse, as I think they call it, is that above 100 meters or so an ice cliff will become unstable and collapse. For some reason they think the collapse will continue until the glacier evacuates itself like a bowel movement or something. I can’t fathom where they come up with such an idea, but this article says that it’s models.
“However, the loss of these ice shelves would supposedly cause the glaciers to collapse into the sea. This is based entirely on models.”
This (theoretical) ice-sheet collapse can only happen under very special circumstances:
1. The depth of the sea at the ice-front must be >90 % of the thickness of the ice in order to lift the ice off the bottom
2. The ground under the glacier must slope downwards inland away from the coast and the ice front.
3. This landward downslope must be monotonous without thresholds and it must be steeper than the top of the glacier.
If these three conditions are fulfilled an icecap could theoretically calve out quickly, say in a few thousand years. It is however doubtful if it has ever happened. If the West Antarctic icecap was prone to such behaviour as alarmists claim one would expect that there would be a number of layers with large amounts of IRD (Ice Rafted Debris) in the Southern Ocean rather like the Heinrich Events in the North Atlantic but vastly bigger. There isn’t.
Dave:
But not enough judging by the begging letters. It is now merely a propaganda machine for the backers, whoever they are.; lurking in the shadows.
tty
December 13, 2018 3:14 pm
As for ice shelves, there are hardly any in East Antarctica.
“However, we should note that some of the world’s glaciers have parts that are below sea level. This ice will not affect sea level if it melted. The volume of glacier ice below the surface of the ocean should therefore be subtracted from the total volume of glaciers and ice caps when calculating sea level equivalents ”
More than that. Glacier ice has a density of 0.91 (actually a bit less since the top 100 meters is compacted snow not ice). The water after melting has a density of about 1.03 (being cold and salt). This means that if a glacier grounded e. g. 200 meters below sea-level melts not only those 200 meters of ice but also another 25-30 meters of ice will be needed to fill out the space the glacier previously occupied, before there is any left to raise sea-level. It is this effect that is the reason that a complete melting of the West Antarctic Ice-sheet would have less than half as much effect on sea-level than the melting of the Greenland Ice-sheet which is actually much smaller
Steve Reddish
December 13, 2018 5:13 pm
“This Antarctic region stores a vast amount of ice, which, if lost, would in the long-term raise global sea level by tens of metres and drown coastal settlements around the world.”
Before I start panicking, can they give us a ballpark estimate of the time to melt-down?
Are they thinking 10,000 or 100,000 or 1,000,000 years? How long-term are they thinking?
Never mind how long until tens of metres of global sea level rise – just tell me how long until the 1st metre of rise, please. First things first.
I don’t know what’s happening. I have seen other people’s reply get duplicated, but I seem to just get my signature duplicated.
SR
MarkW
December 13, 2018 5:50 pm
If the models say it’s melting, then it’s melting. Even if we have to adjust the data.
Shuah
December 13, 2018 6:50 pm
We humans are the stupidest species on Earth. One segment stupidly creates climate change alarmism for nefarious agendas, one segment stupidly believes climate change alarmism, and the other segment who knows it’s all a massive scam stupidly lets the other two segments get away with it. Their premises are fallacies. Why does this global charade continue? Why can’t we defeat them and actually progress as a civilization. Instead, criminals are in complete control, and civilization is steadily decaying. For those who have power to fight them and reverse this, it’s time to grow a pair and stand up to the tyrants, because current tactics are failing.
michael hart
December 13, 2018 7:43 pm
“Change in ocean heat flux is a plausible physical mechanism to explain past and projected changes in this sector of the East Antarctic Ice Sheet and its contribution to sea level.”
In some ways it appears carefully worded such that, without explicitly stating it, the BBC can run with the story and lead the unwary or ill-informed reader into thinking it’s global warming again. And the BBC most certainly did run with the story and do just that.
I don’t buy the warmer-water-due-to-global-warming implication at all. Antarctic sea ice has of course seen record highs in recent years so there isn’t a surge of warm water near the surface. And upwelling of deeper water would be water that is much older than any recent global warming. Basically they just don’t know, but still like to plant the seed in peoples minds even when they have less than no good evidence for what they would like to claim.
The other habit the BBC seem to have developed is to not enable comments on articles until sometime after it is published. Though I haven’t checked, I wouldn’t be surprised if this was then timed such that the BBC green hacks get to tweet their followers so they can turn up and be supportive in the comments after other general readers have already read the article and left in disgust without being able to comment. Unfortunately I just don’t have the stomach to follow the usual suspects on Twitter and check if this is actually the case.
J Mac
December 13, 2018 8:16 pm
The Guardian will be long, looooong gone before the East Antarctic ice shelves melt!
‘Good riddance to bad rubbish.’
Alan Tomalty
December 13, 2018 9:35 pm
So for those of you that were wondering , the final figure is: To increase the global sea level by 1mm, the Totten glacier would have to melt for 53 years.
RoHa
December 13, 2018 9:37 pm
The conclusion is wrong. It should be:
“Antarctic glaciers aren’t doing anything now that they haven’t been doing for the past 12,000 years.”
WXcycles
December 14, 2018 12:38 am
So, in essence Davo, what you’re saying is that Antarctica is a super-duper-mega glacier that’s still continuously advancing rapidly, to the extent that it keeps breaking off from the continent and spreading-out and cooling down the surrounding ocean?
Gee Willikers!
How come the IPCC don’t seem to understand the nature of that process?
This story was also carried by the BBC three days ago.
The audio interview with Dr Catherine Walker is interesting for the vagueness. At 2.30 there is a question on the scale of the changes.
“Physically the fastest changing one is Vincennes Bay which is why we were looking at that one. And, for instance, in 2017 they changed average about .5 meters a year. So that is pretty small.”
Dr Walker than goes on to relate this to Fleming Glacier in West Antartica, which lost about 8 meters.
Well, I did take a drive to a local fishing hole to see if it had melted, but there was someone out there on the ice with a fishing line down a hole, trolling for trout or bass, no doubt.
And despite the dire warnings and weeping and wailing and gnashing of teeth, I found plenty of fresh produce at the grocery store yesterday, so I’m good to go. I’m wondering now just how long it will be until the people who produce these dire predictions realize that: a) nobody believes them because our own eyes refute their claims, and b) they are turning into boring, boring, boring rinse-repeat prognosticators?
They probably won’t stop until the croak, will they?
Years ago, NASA studies were showing that it was gaining ice. Now NASA studies show that it is loosing ice faster than ever. NASA seems schizophrenic. What the hell is a person supposed to believe? Does anybody really know what Antarctica is doing?
Is there an Arctic expert out there who can put it into proper perspective? Until apple orchards are grown there, I cannot believe anybody, at this point.
Ice melts. Ice melts and gains in cycles, yes? Where are we in the cycles? Have we lived long enough to KNOW where we are in the cycles? Are current humans like newborn babies, maybe, who have never seen vast ice continents melt and regrow? — we don’t live long enough to see the regrowth? — we judge by our measly life spans? (which happen to be contemporaneous with the melt now?) [I don’t know — I suspect — I’m asking]
Ian_UK
December 14, 2018 9:35 am
The BBC is pushing a study suggesting increasing wind speed is causing the problem, or part of it:
Scientists believe remote Bouvet Island in the South Atlantic can tell them about the changing winds blowing around Antarctica. These winds have strengthened in recent decades and have pulled up warm ocean water from the deep. This warm water is causing glaciers at the edge of the continent to melt. Amy King from the British Antarctic Survey spoke with our science correspondent Jonathan Amos.
These so-called ‘Scientists” lie like rugs. 2008? 1994? No, not scientists, no scientist would ever make such pronouncements.
Antarctic has a lot of ice. Sometimes it gets bigger, sometimes it stays the same, sometimes it gets smaller, and now we measure it, which we never did before. Sometimes alarmists get published. Pretty much the entire story…
thomho
December 17, 2018 4:13 am
Antarctica is 1.7 times the size of Australia – which is 7.7mkm2
Thus Antarctica at 13.1 km2 and with average depth of its ice of 3 km contains about some 39 km3 of ice-give or take a few cubes
One MSM ( Melbourne Age) published an article a few years ago by (who other than ) an academic who opined that the Antarctic ice sheet would be gone within a decade
Others may be able to calculate what sort of warming would be needed to melt 39 km3 of ice within ten years
They might also like to suggest where such warming might come from -particularly as the average temperatures of the continent are -28c in summer and -60c at the south pole, while at sea level the average summer temperature is -12c and -45c in winter
thomho
December 17, 2018 4:29 am
oops sorry
Forgot to insert the necessary M for millions
So my post should have read
“Thus Antarctica at 13.1 million km 2 and with an average depth of ice of 3 km contains about 39 million km 3 of ice -give or take a few cubes
Thus the question would then read” Others may be able to calculate what sort of warming would be needed to melt 39 million km3 of ice within ten years”
Is this sort of “stuff ” all they have ?
Sad .
But it sells in the MSM.
Apparently, a significant proportion of its daily sales are to that other Progressive sinkhole, the BBC. Without that, actual sales to the public are much smaller.
It is sad that left-wing political activists and their media supporters seized on global warming to advance their anti-West crusades.
Don’t worry – the paper may not be around much longer. The latest financial results of the Graun’s holding company have just come out. Worse than ever despite begging letters on the website for contributions.
It is wasn’t the left’s only proper newspaper, it would have disappeared long ago as so few buy it or advertise in it. There are limits as to how many times benefactors will be prepared to bail it out.
Don’t worry if the Grauniad fails, there will always be the Canberra Times.
The Guardian is supported by the billion pound Scott Trust. They have managed to get losses down to around £20 million a year which means that the Guardian will probably keep going for ever. It’s a truly dreadful newspaper but some people like it. One thing about the Guardian is that its biases are plain for all to see.
Is there anything they do that doesn’t involve models? It’s like they are a bunch of children that never wanted to stop playing computer and actually grow up
I’m not a scientist but I thought direct observation was the foundation
Of course it’s melting, was gone by 2013 per Al Gore, we are ice free now……Hurricanes are expected down there in 2019
I am trying to figure out how we have ice on the ponds here in Ky and the poles are ice free?
Just a regional anomaly.
You are in a “warm hole”.
Oh noes! The “missing heat” has migrated south!
“More detailed studies are needed to quantify the impact of ocean temperature on ice dynamics in this important sector of East Antarctica.”
i.e. Send more money!
3 point plan to save the planet:
1: Send money.
2: Send more money.
3: Send us all your money.
4. put us in charge
All the article says is that the glaciers are being melted by the sea. Isn’t this always the case for ocean outlet glaciers? No mention of the interior land end being replenished with snow. And glaciers often advance faster for a few years and slower for a few. And, Antarctic ice mass has increased. So all in all, a disingenuous article.
I should have mentioned that Totten Glacier is right next door to Law Dome, where there is an extremely high snow/ice accumulation rate.
David Is there any longterm data on ocean temps in that area?
Don’t think so.
Yep. Basically this article says that this glacier is doing what glaciers do.
Does anyone have a comment on the now permanent cold anomaly in SST over large areas of the Southern Ocean all around Antarctica?
To me this does not seem consistent with a warming or melting Antarctic continent.
Especially given it’s been cold for many, many years.
“If the ice shelves supposedly buttressing these glaciers melted, sea level would barely notice.
However, the loss of these ice shelves would supposedly cause the glaciers to collapse into the sea. This is based entirely on models.”
How could glaciers continue to collapse when the collapsed ice cliff would act as a buttress against further collapse?
I can’t imagine floating sea ice offering a resistance to glaciers that is greater than the resistance encountered at bedrock by the glaciers. The key to this appears to be the sea ice that is grounded. That is, the sea ice is experiencing friction at the grounding line. Assuming, for the sake of argument, that the grounded sea ice were to break off and float away, there might be a temporary surge in the glacier. But, when the tongue of the glacier gets to the grounding line, I would expect it to come to a ‘screeching’ halt. The loss of the sea ice isn’t a “tipping point,” but rather, a new equilibrium.
I think the concept behind catastrophic ice collapse, as I think they call it, is that above 100 meters or so an ice cliff will become unstable and collapse. For some reason they think the collapse will continue until the glacier evacuates itself like a bowel movement or something. I can’t fathom where they come up with such an idea, but this article says that it’s models.
“However, the loss of these ice shelves would supposedly cause the glaciers to collapse into the sea. This is based entirely on models.”
This (theoretical) ice-sheet collapse can only happen under very special circumstances:
1. The depth of the sea at the ice-front must be >90 % of the thickness of the ice in order to lift the ice off the bottom
2. The ground under the glacier must slope downwards inland away from the coast and the ice front.
3. This landward downslope must be monotonous without thresholds and it must be steeper than the top of the glacier.
If these three conditions are fulfilled an icecap could theoretically calve out quickly, say in a few thousand years. It is however doubtful if it has ever happened. If the West Antarctic icecap was prone to such behaviour as alarmists claim one would expect that there would be a number of layers with large amounts of IRD (Ice Rafted Debris) in the Southern Ocean rather like the Heinrich Events in the North Atlantic but vastly bigger. There isn’t.
But it sells in the MSM.
Dave:
But not enough judging by the begging letters. It is now merely a propaganda machine for the backers, whoever they are.; lurking in the shadows.
As for ice shelves, there are hardly any in East Antarctica.
“However, we should note that some of the world’s glaciers have parts that are below sea level. This ice will not affect sea level if it melted. The volume of glacier ice below the surface of the ocean should therefore be subtracted from the total volume of glaciers and ice caps when calculating sea level equivalents ”
More than that. Glacier ice has a density of 0.91 (actually a bit less since the top 100 meters is compacted snow not ice). The water after melting has a density of about 1.03 (being cold and salt). This means that if a glacier grounded e. g. 200 meters below sea-level melts not only those 200 meters of ice but also another 25-30 meters of ice will be needed to fill out the space the glacier previously occupied, before there is any left to raise sea-level. It is this effect that is the reason that a complete melting of the West Antarctic Ice-sheet would have less than half as much effect on sea-level than the melting of the Greenland Ice-sheet which is actually much smaller
“This Antarctic region stores a vast amount of ice, which, if lost, would in the long-term raise global sea level by tens of metres and drown coastal settlements around the world.”
Before I start panicking, can they give us a ballpark estimate of the time to melt-down?
Are they thinking 10,000 or 100,000 or 1,000,000 years? How long-term are they thinking?
Never mind how long until tens of metres of global sea level rise – just tell me how long until the 1st metre of rise, please. First things first.
SR
SR
I don’t know what’s happening. I have seen other people’s reply get duplicated, but I seem to just get my signature duplicated.
SR
If the models say it’s melting, then it’s melting. Even if we have to adjust the data.
We humans are the stupidest species on Earth. One segment stupidly creates climate change alarmism for nefarious agendas, one segment stupidly believes climate change alarmism, and the other segment who knows it’s all a massive scam stupidly lets the other two segments get away with it. Their premises are fallacies. Why does this global charade continue? Why can’t we defeat them and actually progress as a civilization. Instead, criminals are in complete control, and civilization is steadily decaying. For those who have power to fight them and reverse this, it’s time to grow a pair and stand up to the tyrants, because current tactics are failing.
In some ways it appears carefully worded such that, without explicitly stating it, the BBC can run with the story and lead the unwary or ill-informed reader into thinking it’s global warming again. And the BBC most certainly did run with the story and do just that.
I don’t buy the warmer-water-due-to-global-warming implication at all. Antarctic sea ice has of course seen record highs in recent years so there isn’t a surge of warm water near the surface. And upwelling of deeper water would be water that is much older than any recent global warming. Basically they just don’t know, but still like to plant the seed in peoples minds even when they have less than no good evidence for what they would like to claim.
The other habit the BBC seem to have developed is to not enable comments on articles until sometime after it is published. Though I haven’t checked, I wouldn’t be surprised if this was then timed such that the BBC green hacks get to tweet their followers so they can turn up and be supportive in the comments after other general readers have already read the article and left in disgust without being able to comment. Unfortunately I just don’t have the stomach to follow the usual suspects on Twitter and check if this is actually the case.
The Guardian will be long, looooong gone before the East Antarctic ice shelves melt!
‘Good riddance to bad rubbish.’
So for those of you that were wondering , the final figure is: To increase the global sea level by 1mm, the Totten glacier would have to melt for 53 years.
The conclusion is wrong. It should be:
“Antarctic glaciers aren’t doing anything now that they haven’t been doing for the past 12,000 years.”
So, in essence Davo, what you’re saying is that Antarctica is a super-duper-mega glacier that’s still continuously advancing rapidly, to the extent that it keeps breaking off from the continent and spreading-out and cooling down the surrounding ocean?
Gee Willikers!
How come the IPCC don’t seem to understand the nature of that process?
This story was also carried by the BBC three days ago.
The audio interview with Dr Catherine Walker is interesting for the vagueness. At 2.30 there is a question on the scale of the changes.
“Physically the fastest changing one is Vincennes Bay which is why we were looking at that one. And, for instance, in 2017 they changed average about .5 meters a year. So that is pretty small.”
Dr Walker than goes on to relate this to Fleming Glacier in West Antartica, which lost about 8 meters.
https://www.bbc.co.uk/news/science-environment-46517396
Well, I did take a drive to a local fishing hole to see if it had melted, but there was someone out there on the ice with a fishing line down a hole, trolling for trout or bass, no doubt.
And despite the dire warnings and weeping and wailing and gnashing of teeth, I found plenty of fresh produce at the grocery store yesterday, so I’m good to go. I’m wondering now just how long it will be until the people who produce these dire predictions realize that: a) nobody believes them because our own eyes refute their claims, and b) they are turning into boring, boring, boring rinse-repeat prognosticators?
They probably won’t stop until the croak, will they?
So, what’s the truth about Antarctica?
Years ago, NASA studies were showing that it was gaining ice. Now NASA studies show that it is loosing ice faster than ever. NASA seems schizophrenic. What the hell is a person supposed to believe? Does anybody really know what Antarctica is doing?
Is there an Arctic expert out there who can put it into proper perspective? Until apple orchards are grown there, I cannot believe anybody, at this point.
Ice melts. Ice melts and gains in cycles, yes? Where are we in the cycles? Have we lived long enough to KNOW where we are in the cycles? Are current humans like newborn babies, maybe, who have never seen vast ice continents melt and regrow? — we don’t live long enough to see the regrowth? — we judge by our measly life spans? (which happen to be contemporaneous with the melt now?) [I don’t know — I suspect — I’m asking]
The BBC is pushing a study suggesting increasing wind speed is causing the problem, or part of it:
Scientists believe remote Bouvet Island in the South Atlantic can tell them about the changing winds blowing around Antarctica. These winds have strengthened in recent decades and have pulled up warm ocean water from the deep. This warm water is causing glaciers at the edge of the continent to melt. Amy King from the British Antarctic Survey spoke with our science correspondent Jonathan Amos.
https://www.bbc.co.uk/news/av/science-environment-46547586/ice-core-record-of-antarctic-winds
“Ain’t it Awful?”
These so-called ‘Scientists” lie like rugs. 2008? 1994? No, not scientists, no scientist would ever make such pronouncements.
Antarctic has a lot of ice. Sometimes it gets bigger, sometimes it stays the same, sometimes it gets smaller, and now we measure it, which we never did before. Sometimes alarmists get published. Pretty much the entire story…
Antarctica is 1.7 times the size of Australia – which is 7.7mkm2
Thus Antarctica at 13.1 km2 and with average depth of its ice of 3 km contains about some 39 km3 of ice-give or take a few cubes
One MSM ( Melbourne Age) published an article a few years ago by (who other than ) an academic who opined that the Antarctic ice sheet would be gone within a decade
Others may be able to calculate what sort of warming would be needed to melt 39 km3 of ice within ten years
They might also like to suggest where such warming might come from -particularly as the average temperatures of the continent are -28c in summer and -60c at the south pole, while at sea level the average summer temperature is -12c and -45c in winter
oops sorry
Forgot to insert the necessary M for millions
So my post should have read
“Thus Antarctica at 13.1 million km 2 and with an average depth of ice of 3 km contains about 39 million km 3 of ice -give or take a few cubes
Thus the question would then read” Others may be able to calculate what sort of warming would be needed to melt 39 million km3 of ice within ten years”