Claim: Antarctic sea-level rising faster than global rate, but a ‘pause’ and other studies suggest ice melt isn’t the only factor

From the University of Southampton

A new study of satellite data from the last 19 years reveals that fresh water from melting glaciers has caused the sea-level around the coast of Antarctica to rise by 2cm more than the global average of 6cm.

Researchers at the University of Southampton detected the rapid rise in sea-level by studying satellite scans of a region that spans more than a million square kilometres.

The melting of the Antarctic ice sheet and the thinning of floating ice shelves has contributed an excess of around 350 gigatonnes of freshwater to the surrounding ocean. This has led to a reduction in the salinity of the surrounding oceans that has been corroborated by ship-based studies of the water.

“Freshwater is less dense than salt water and so in regions where an excess of freshwater has accumulated we expect a localised rise in sea level,” says Craig Rye, lead author of the paper that has been published in the journal Nature Geoscience.

In addition to satellite observations, the researchers also conducted computer simulations of the effect of melting glaciers on the Antarctic Ocean. The results of the simulation closely mirrored the real-world picture presented by the satellite data.

“The computer model supports our theory that the sea-level rise we see in our satellite data is almost entirely caused by freshening (a reduction in the salinity of the water) from the melting of the ice sheet and its fringing ice shelves,” says Craig.

“The interaction between air, sea and ice in these seas is central to the stability of the Antarctic Ice Sheet and global sea levels, as well as other environmental processes, such as the generation of Antarctic bottom water, which cools and ventilates much of the global ocean abyss.”

The research was carried out in close collaboration with researchers at the National Oceanography Centre and the British Antarctic Survey.

###


 

The full paper Rapid sea-level rise along the Antarctic margins in response to increased glacial discharge is published in Nature Geoscience.

Rapid sea-level rise along the Antarctic margins in response to increased glacial discharge

Craig D. Rye, Alberto C. Naveira Garabato, Paul R. Holland, Michael P. Meredith, A. J. George Nurser, Chris W. Hughes, Andrew C. Coward & David J. Webb

Nature Geoscience (2014) doi:10.1038/ngeo2230

The Antarctic shelf seas are a climatically and ecologically important region, and are at present receiving increasing amounts of freshwater from the melting of the Antarctic Ice Sheet and its fringing ice shelves1, 2, primarily around the Antarctic Peninsula and the Amudsen Sea. In response, the surface ocean salinity in this region has declined in past decades3, 4, 5, 6, 7, 8, 9. Here, we assess the effects of the freshwater input on regional sea level using satellite measurements of sea surface height (for months with no sea-ice cover) and a global ocean circulation model. We find that from 1992 to 2011, sea-level rise along the Antarctic coast is at least 2  ±  0.8 mm yr−1 greater than the regional mean for the Southern Ocean south of 50° S. On the basis of the model simulations, we conclude that this sea-level rise is almost entirely related to steric adjustment, rather than changes in local ocean mass, with a halosteric rise in the upper ocean and thermosteric contributions at depth. We estimate that an excess freshwater input of 430 ± 230 Gt yr−1 is required to explain the observed sea-level rise. We conclude that accelerating discharge from the Antarctic Ice Sheet has had a pronounced and widespread impact on the adjacent subpolar seas over the past two decades.

===========================================

Fortunately, they provide an SI file, seen here:  http://www.nature.com/ngeo/journal/vaop/ncurrent/extref/ngeo2230-s1.pdf

Figure S4 is telling:

figureS4_

Figure S4: Time series of Antarctic subpolar sea SSH anomaly showing continuously sea ice-free record. The circumpolar mean of the SSH anomaly south of the oceanic boundary of the Antarctic coastal sea level rise signal (Fig. 1) is indicated in red. Data gaps show times of widespread sea ice cover. The mean of the SSH anomaly in a small subset of the Antarctic subpolar seas that is permanently sea ice-free is indicated in black. Both data sets have had the global-mean rate of sea level rise subtracted.

It seems there is a “pause” that has developed in SLR around Antarctica starting around 2005 continuing through 2012.

For reference, this map from NOAA/NESDIS shows that there is in fact about 2 cm of SLR around some parts of Antractica, but the main SLR is a big red patch in the Western Pacific:

Sea_level_MSSH_2011-1993_300While the Rye et al. paper says ice melt from the continent is the cause, it may also be simply a matter of winds. Note that the red spotch of SLR on the map above is mainly an issue of winds and ENSO. Around Antarctica, we have a strong circumpolar wind pattern, as is seen in the video below about ozone over Antarctica:

That circumpolar wind pattern around Antarctica can act as a sea level rise enhancer, as described in this paper:

Rapid subsurface warming and circulation changes of Antarctic coastal waters by poleward shifting winds

Spence et al. 2014

Abstract

The southern hemisphere westerly winds have been strengthening and shifting poleward since the 1950s. This wind trend is projected to persist under continued anthropogenic forcing, but the impact of the changing winds on Antarctic coastal heat distribution remains poorly understood. Here we show that a poleward wind shift at the latitudes of the Antarctic Peninsula can produce an intense warming of subsurface coastal waters that exceeds 2 °C at 200-700 m depth. The model simulated warming results from a rapid advective heat flux induced by weakened near-shore Ekman pumping, and is associated with weakened coastal currents. This analysis shows that anthropogenically induced wind changes can dramatically increase the temperature of ocean water at ice sheet grounding lines and at the base of floating ice shelves around Antarctica, with potentially significant ramifications for global sea level rise.

Bottom line: I’m not much worried about the claims made about SLR in Antarctica being due to ice melt. There may be some enhancement, but to say it is the sole reason, when other fcators are clearly at play is just your typical climate alarmism at work.

 UPDATE: Having written this piece late in the evening, my fatigue must have caused me to forget this graphic. Temperature over Antarctica seems to to be ever so slightly negative trending.

 

 

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111 thoughts on “Claim: Antarctic sea-level rising faster than global rate, but a ‘pause’ and other studies suggest ice melt isn’t the only factor

  1. So the fact that Antarctic sea ice has been rapidly increasing over the last few years has passed them by then? Or is it an inconvenient fact that must be overlooked in the name of climate alarmism?

      • I just read the abstract:

        Furthermore, while the amplitude of GHG forcing has been similar at the poles, significant ozone depletion only occurs over Antarctica. We suggest that the initial response of SST around Antarctica to ozone depletion is one of cooling and only later adds to the GHG-induced warming trend as upwelling of sub-surface warm water associated with stronger surface westerlies impacts surface properties.

        So is the hole in the ozone layer getting bigger or smaller?
        If it’s growing then the cooling can be explained.

        But it is getting smaller.
        So I don’t think this paper sheds mush light on the matter.

      • Not much light though. The final paragraph reads (my emphasis):

        ‘We SPECULATE that the period through which we are now passing MAY be one in which the delayed warming of SST associated with GHG forcing around Antarctica is largely cancelled by the cooling effects associated with the ozone hole. By mid-century, however, ozone-hole effects MAY instead be adding to GHG warming around Antarctica but with diminished amplitude as the ozone hole heals. The Arctic, meanwhile, responding to GHG forcing but in a manner amplified by ocean heat transport, MAY continue to warm at an accelerating rate.’

        Yet another hypothesis built upon the hypothesis that CO2 emissions MAY cause significant warming. The trouble is that the latter hypothesis has now gained the status of a faith.

      • “…while the amplitude of GHG forcing has been similar at the poles, significant ozone depletion only occurs over Antarctica. We suggest that the initial response of SST around Antarctica to ozone depletion is one of cooling and only later adds to the GHG-induced warming trend as upwelling of sub-surface warm water associated with stronger surface westerlies impacts surface properties.”

        The effect of ozone depletion is to let more SW ( UV ) solar energy enter the troposphere. Cooling stratosphere and warming oceans.

        http://climategrog.wordpress.com/?attachment_id=988

        Since UV penetrates to some depth it takes several years to heat the bulk of water. It appears from that graph that it takes 5 or 6 years to regain something like a stable level after a relatively step-like event of a major eruption.

        The suggests relaxation response with a timeconstant of about 1.5 years to adjust to the new radiative balance. That would explain the delayed warming.

      • “We speculate that the period through which we are now passing may be one in which the delayed warming of SST associated with GHG forcing around Antarctica is largely cancelled by the cooling effects associated with the ozone hole. By mid-century, however, ozone-hole effects may instead be adding to GHG warming around Antarctica but with diminished amplitude as the ozone hole heals.”

        Interestingly, this paper takes a similar approach of using step functions that I have used in looking Mt Pinatubo effects, so is talking the same language. Looking at their figure 3 , the ozone step response of the MIT ocean only model takes about 20y to settle.

        Three of four time longer than what I found in SH SST response to changes in global stratospheric ozone.

        Looks like some of the “parameters” of the negative feedbacks in their model need tweaking.

      • M Courtney says:
        So I don’t think this paper sheds [mush] light on the matter.

        Mush does not need light; it grows best in the dark.

    • I don’t think the sea ice is nearly as important as the AIS volume, which is declining. See Helm, V., Humbert, A., and Miller, H.: Elevation and elevation change of Greenland and Antarctica derived from CryoSat-2, The Cryosphere Discuss., 8, 1673-1721, doi:10.5194/tcd-8-1673-2014, 2014

  2. Here is a crazy idea. Maybe the increasing ice, which is increasing mass, caused increasing gravity which caused increasing sea level.

    • Crazy if you are considering sea-ice which is floating and very thin, but very relevant to changes in the mass of the Antarctic icecap which have a considerable effect on sea-levels. A higher sea-level would suggest a thickening icecap, but of course that is an absolutely forbidden thought….

      • Not a so forbiden thought in a case of a decreasing sea lvl…..if by any chance there was or will be a reverse and a sea lvl decreament observed then the models will be showing that been due to the thinning and loss of icecap mass….and voila again AGW…..:))
        For as long as there a model mentioned don’t be surprised while any thing possible under the sun is due to AGW.
        As far as models concerned anything ever was, is and always will be due to AGW.

        One thing these models got right though……never ever daring to piss off their “masters” by disagreeing with the expectation to support the AGW, anytime anywhere requiried……otherwise they get fried or tortured till they at last get it right… :)

    • It seems that my silly comment was not clear. The ice on the continent is increasing so the gravity of the continent would increase and like the moon pull more water toward it.

      • Gravity just isn’t that influential. However … increased ice over the continent would lead to isostatic changes (the continent sinks proportionate to mass gained and the plasticity of the mantle beneath. Increased mass also creates some really odd conditions beneath the ice cap where pressure leads to supercooled, high-pressure water (stays in the liquid phase), which is discharged from beneath the edges of the ice with interesting results.

  3. So they call the poleward winds anthropogenically induced with no scientific evidence whatsoever?
    The only anthropogenic cause they talk about is CO2 yet there has been no global warming for 17 years so how can it be causing the ice melt.
    Also they talk about the Arctic warming faster than the rest of the planet hence the lack of Antarctic ice melt, now they expect us to believe that the antarctic is melting and the Arctic cooling.

    Wow…just…wow.

  4. I’m sorry, but a SL rise of 2mm (+/- 0.8mm)/yr for a period of 19 yrs results in a 3.8cm (+/- 1.5cm) rise. That means a maximum rise, along the Antarctic coast, of 5.3cm and a minimum of 2.3cm over that 19 year period. A claim that the SL rise is 2cm over the Global average is preposterous. If the Average Global SL rise over the same time period is 6cm, then the Antarctic SL rise has been 0.68cm less (at the maximum), and 3.72cm less (at the minimum) than the average and 2.68 to 5.72 cm less than what they are claiming – which is “fresh water from melting glaciers has caused the sea-level around the coast of Antarctica to rise by 2cm more than the global average of 6cm”.

    • Uh ho. 19 years!

      A new study of satellite data from the last 19 years reveals that fresh water from melting glaciers has caused the sea-level around the coast of Antarctica to rise by 2cm more than the global average of 6cm.

      But just yesterday we had this wonderful story on WUWT.

      Does Antarctic Sea Ice Growth Negate Global Warming Theory?
      ……..According to Stammerjohn, it’s even possible that the current growth spurt is just a short upward wiggle in a larger downward trend. “Thirty years isn’t really that long,” Stammerjohn said.

      http://wattsupwiththat.com/2014/08/31/does-antarctic-sea-ice-growth-negate-global-warming-theory/

      It’s a good thing these people aren’t on trial.

    • Mike Tremblay September 1, 2014 at 12:49 am
      “I’m sorry, but a SL rise of 2mm (+/- 0.8mm)/yr for a period of 19 yrs results in a 3.8cm (+/- 1.5cm) rise. “

      Rye et al say (in press release):
      “A new study of satellite data from the last 19 years reveals that fresh water from melting glaciers has caused the sea-level around the coast of Antarctica to rise by 2cm more than the global average of 6cm.”

      The abstract says:
      “We find that from 1992 to 2011, sea-level rise along the Antarctic coast is at least 2 ± 0.8 mm yr-1 greater than the regional mean for the Southern Ocean south of 50° S.”

      How is this inconsistent?

    • Look on the bright side; if the Antarctic sea level has risen 2cm more than the global average, somewhere else has risen 2cm less than the global average

  5. Sorry about my ignorance, I always thought the Antarctic remained below freezing (I am aware the Arctic rises above). So, the temp DOES go above freezing – allowing ice to melt? Is that correct? Would someone be kind enough to answer?

  6. So, please could they explain how the “ice sheets are melting”. Sublimation is possible by the application of a lot of sunlight , otherwise how in hell’s name does ice melt at -20 to -70°C ?

    Marlow Metcalf

    September 1, 2014 at 12:15 am

    Here is a crazy idea. Maybe the increasing ice, which is increasing mass, caused increasing gravity which caused increasing sea level.

    and the extra weight is making the land mass sink ?

    Grace, don’t know what pile of …………… you appeared from but it has warped you mind.

    • Stephen Richards

      I write to defend Peter Grace.

      The recent Appell affair makes us all suspicious of dissenting newcomers, but such suspicion needs to be balanced by calm consideration.

      We need people with different viewpoints so all ideas can be presented and assessed. Therefore, we need to encourage presentation of opposing opinions so we can oppose them. Peter Grace has been presenting a different view, and I dispute his view, but I see no evidence that he has been trolling. Hence, so far he has been presenting a useful foil.

      Trolls attempt to prevent rational debate by distorting discussions and deflecting discussions from their subject. Trolls need to be hammered. And I despise them.

      I think that at present Peter Grace is performing a useful function for which he deserves our gratitude. And I think that that if he – or anybody else – starts trolling then he would deserve to be slammed, but not otherwise.

      Richard

      • markstoval

        A character by the name of David Appell created a number of false persona who posted to a series of WUWT threads with the clear intention of causing disruption and destruction of discussions. Some of these persona were vary strange individuals and some acted in support of each other (well, in reality they were the same person).

        The matter first came to light when Appell could no longer control his infantile glee and sent an email to our host which boasted what Appell was doing and said his purpose was to “mess with {our host’s} head”.

        Richard

      • I also agree. I became skeptical of CAGW by listening to view points I didn’t agree with. It was a warning to me not to be so certain of what I thought I knew, and I now seek out countering views to ensure I don’t fall into that trap again. The posts Peter Grace has posted have largely been on point and without denigration.

  7. Marlow Metcalf says: September 1, 2014 at 12:15 am “Here is a crazy idea. Maybe the increasing ice, which is increasing mass, caused increasing gravity which caused increasing sea level.”

    To have an increased sea level due to gravity would need, for the increased sea level to remain increased, lesser gravity in that area. Rather difficult to see how actual gravity could be reduced unless there is marked change in the earth’s mantle or core.

    Increasing ice would have no effect – since ice floats, it displaces its own mass of water, therefore there would be only the minutest effect on local gravity due to the mass of ice above the level of the observer (or since the observer is up there but is calibrating it at sea level, the effect on general sealevel in the vicinity would be negligible other than edge of the iceberg.

    However, since some of the tabular icebergs are massive, could this local reduction in gravity due to the mass of ice above sea level have caused a “local” increase in sea level which is being averaged out by the satellite to produce the anomaly?

    • Actually the increased mass of a growing icecap does attract the water in surrounding oceans and pull up the sea-level. This effect is surprisingly strong and amounts to several meters for the entire Antarctic icecap. Actually this is a confounding factor in any historical measurements of sea-level near Antarctica since we don’t know changes in the local gravity field with any precision before GRACE.

  8. Notable about the NOAA visualisation map are the large areas of grey near the poles. Presumably these mark the region where there is no satellite data.

  9. ‘A region which spans more than a million square kilometers.’

    7% of the continent. Which leads one to wonder: How much is the rest of the continent GAINING in snow and ice accumulation?

    Why is it we never hear the other half of the equation?

  10. Greater sea level rise in the western Pacific, where the trade winds drive the warmer less dense surface water in the equatorial pacific; who should be surprised, I’m not. After all it’s just basic high school physics.

    Yes there is nothing new under the sun.

    • What’s the provenance of the NOAA mapping, and for what period? shows 6cm in front of my place. “Who should be surprised” – I am.
      This may not be much but I think this would have been noticed.
      Local measurements don’t seem to indicate anything. Longer term? Nada.

  11. 2 cm is less than an inch. Now just how far does the ice extend outwards from the shoreline and just how deep/tall is the ice both on shore and that floating over the sea?

    There are other things to worry about such as paying the taxes to keep the CAGW grant gravy train rolling

  12. How do we know that these observations are not demonstrating the combined effect of apsis and nodal rotation variations in the orbit of the moon on earth’s oceanic tides in the Antarctic?

  13. “The melting of the Antarctic ice sheet and the thinning of floating ice shelves ”

    These are the thinning ice shelves discovered by Chris Turney?

  14. I blame it on poor climate “science” communication. If Professor Turkey had known about this disastrous sea level rise, the Ship of Fools fiasco might never have happened.

  15. I dont know why WUWT gives any attention to this AGW drivel article and journal Once you see this
    “amounts of freshwater from the melting of the Antarctic Ice Sheet and its fringing ice shelves” when it is blatantly obvious that Antarctic Ice sheet is freezing more (increasing) for the past 3 years. Check out CT today (a warmist site but has to show the data).

  16. “While the Rye et al. paper says ice melt from the continent is the cause, it may also be simply a matter of winds.”

    Rye et al says that salinity has reduced. Winds couldn’t cause that, nor sea ice changes. It needs a source of fresh water. Rye et al say 350 Gtons have been added.

    “The computer model supports our theory that the sea-level rise we see in our satellite data is almost entirely caused by freshening”
    That’s basically just an Archimedes calculation. Equilibration of pressure with the less dense fresher water.

    • Nick: what is the other half of the equation? How many gigatons are being re-deposited upon the continent?

    • We estimate that an excess freshwater input of 430 ± 230 Gt yr−1 is required to explain the observed sea-level rise.

      Ummm… their error range is ~107% of their model’s calculated value. I’m not gonna give that freshening WAG much of a chance of being correct.

    • Nick writes “Rye et al says that salinity has reduced. Winds couldn’t cause that, nor sea ice changes.”

      Increasing sea ice can certainly change the influx of fresh water each summer. Over winter the water freezes and we can no longer accurately measure the sea level in the region under the ice of unknown thickness’s and furthermore the mixing over the winter months would homogenize the salinity in the region ready for the summer melt.

  17. Decreasing Salinity could also be caused by increasing sea ice. Has the sea ice around Antarctica been inreasing?

    • I would have thought that increasing sea ice would increase salinity as the ice doesn’t dissolve so much salt – meaning the layer beneath the new ice is saltier?

      • Unless the flow of saline infused bottom water has increased? But where do they get the idea of thinning sea ice? I see this only in the area affected by geothermal forces. AFAIK, overall sea ice has increased quite dramatically and the majority of south pole SST have cooled slightly, and there has been no warming over the majority of Antarctica.

      • From wik…
        Antarctic bottom water is formed in the Weddell and Ross Seas, off the Adélie Coast and by Cape Darnley from surface water cooling in polynyas and below the ice shelf.[2] A unique feature of Antarctic bottom water is the cold surface wind blowing off the Antarctic continent. The surface wind creates the polynyas which opens up the water surface to more wind. This Antarctic wind is stronger during the winter months and thus the Antarctic bottom water formation is more pronounced during the Antarctic winter season. Surface water is enriched in salt from sea ice formation. Due to its increased density, flows down the Antarctic continental margin and continues north along the bottom. It is the densest water in the free ocean, and underlies other bottom and intermediate waters throughout most of the southern hemisphere. The Weddell Sea Bottom Water is the densest component of the Antarctic bottom water.”

        So yes, the surface is initially saltier, but this is cooled and more dense, so with more sea ice, more salt may be flushed down. Very cold very dense water.

      • Sea ice loses salt as it ages, at least as I understand it. The whole salinity issue revolves around a complex set of possibilities. The paper only really addresses one. And worse, no one seems to want to address the potential of these various processes acting together. The discussion of the formation of eskers related to the development of ice sheets here is noteworthy. The article is unfortunately paywalled.

        http://www.sciencedirect.com/science/article/pii/S0277379108002539

        The gist is that there are extensive water circulation systems beneath ice sheets and ice accumulation conditions have profound effects (in models anyway) one chemistry, circulation patterns, and a host of subglacial phenomena. The conditions and behaviour of water, ice and till beneath glaciers is “problematic.”

  18. 1 million sq km eh. Will their next study be to East Antarctica? We have had some extreme snowfalls there in recent years.

    Abstract – 2 NOV 2012
    Snowfall-driven mass change on the East Antarctic ice sheet
    An improved understanding of processes dominating the sensitive balance between mass loss primarily due to glacial discharge and mass gain through precipitation is essential for determining the future behavior of the Antarctic ice sheet and its contribution to sea level rise. While satellite observations of Antarctica indicate that West Antarctica experiences dramatic mass loss along the Antarctic Peninsula and Pine Island Glacier, East Antarctica has remained comparably stable. In this study, we describe the causes and magnitude of recent extreme precipitation events along the East Antarctic coast that led to significant regional mass accumulations that partially compensate for some of the recent global ice mass losses that contribute to global sea level rise. The gain of almost 350 Gt from 2009 to 2011 is equivalent to a decrease in global mean sea level at a rate of 0.32 mm/yr over this three-year period.

    http://onlinelibrary.wiley.com/doi/10.1029/2012GL053316/abstract

    =================

    Abstract – 7 JUN 2013
    Recent snowfall anomalies in Dronning Maud Land, East Antarctica, in a historical and future climate perspective
    Enhanced snowfall on the East Antarctic ice sheet is projected to significantly mitigate 21st century global sea level rise. In recent years (2009 and 2011), regionally extreme snowfall anomalies in Dronning Maud Land, in the Atlantic sector of East Antarctica, have been observed. It has been unclear, however, whether these anomalies can be ascribed to natural decadal variability, or whether they could signal the beginning of a long-term increase of snowfall. Here we use output of a regional atmospheric climate model, evaluated with available firn core records and gravimetry observations, and show that such episodes had not been seen previously in the satellite climate data era (1979). Comparisons with historical data that originate from firn cores, one with records extending back to the 18th century, confirm that accumulation anomalies of this scale have not occurred in the past ~60 years, although comparable anomalies are found further back in time. We examined several regional climate model projections, describing various warming scenarios into the 21st century. Anomalies with magnitudes similar to the recently observed ones were not present in the model output for the current climate, but were found increasingly probable toward the end of the 21st century.

    http://onlinelibrary.wiley.com/doi/10.1002/grl.50559/abstract

    =================

    Abstract2014
    High-resolution 900 year volcanic and climatic record from the Vostok area, East Antarctica
    …..The strongest volcanic signal (both in sulfate concentration and flux) was attributed to the AD 1452 Kuwae eruption, similar to the Plateau Remote and Talos Dome records. The average snow accumulation rate calculated between volcanic stratigraphic horizons for the period AD 1260–2010 is 20.9 mm H2O. Positive (+13%) anomalies of snow accumulation were found for AD 1661-1815 and AD 1992-2010, and negative (-12%) for AD 1260-1601. We hypothesized that the changes in snow accumulation are associated with regional peculiarities in atmospheric transport.

    http://www.the-cryosphere.net/8/843/2014/tc-8-843-2014.html

  19. funny..I always thought fresh water froze faster than salty, which is why we used a brine bath to make icecream.
    so fresh “fluffy”?? water sits higher.
    aww cmon.

    • You’re right, it does freeze faster, but, fresh water will float on top of brine until mixing equalizes the distribution of solutes in the water. That, however, takes time. Columbus found that out in the Caribbean in fact. They intended to fill water butts from freshwater pools on a limestone island. Dropping the buckets in as deep as they could, to retrieve the coldest water, they were shocked to find the water in the buckets was salt. His crew though they were being teased by demons. In fact the pool was open to the sea.

      Around Antarctica the circumpolar winds and currents tend separate Antarctica from rapid interaction with the rest of the planet. That slows mixing between the water around and air over the continent and the rest of the world. So, if fresh water accumulation out-paces mixing and dispersion, you develop anomalous situations that are limited by the rate the water will disperse outward across the Antarctic circumpolar current surrounding the continent.

    • From the video:
      “The model has allowed geodesists themselves to correctly predict the average level of the ocean to within a meter everywhere on earth.”
      So, are they saying it’s 3mm ± 1meter?

      • That’s the only way that most climate scientism works… claimed measurements invert the normal measurement/tolerance relationship. Climateers almost always use value ranges that are at least two orders of magnitude smaller than the tolerance of the measurement. They fix this by having stastical models infill measurements until they create enough samples to pretend that they have statistically “increased” both accuracy and precision by three orders of magnitude. That means they can measure to +/-1mm with a sea level sensor who’s absolute accuracy is +/-1m. Isn’t climate science fun!

      • And the same problem reappears in the mapping of Greenland and the Antarctic also in the news today.Measurements accurate to a couple of meters are used to measure to the nearest few cm’s. And as pointed out on other blogs, if the completely erroneous results were correct, it would take many hundreds or thousands of years for the ice caps to ‘melt’ away. Total alarmist nonsense.

  20. “Using radar techniques to map how water flows under ice sheets, UTIG researchers were able to estimate ice melting rates and thus identify significant sources of geothermal heat under Thwaites Glacier. They found these sources are distributed over a wider area and are much hotter than previously assumed.
    The geothermal heat contributed significantly to melting of the underside of the glacier, and it might be a key factor in allowing the ice sheet to slide, affecting the ice sheet’s stability and its contribution to future sea level rise.
    The cause of the variable distribution of heat beneath the glacier is thought to be the movement of magma and associated volcanic activity arising from the rifting of the Earth’s crust beneath the West Antarctic Ice Sheet.”
    An example of a glacier in Iceland.
    “There are about 30 known central volcanoes, or volcanic systems, in Iceland. Bárðarbunga, the second highest mountain of Iceland; ca 2000 meters above sea-level, is one of them. The volcano is placed in northwestern Vatnajökull ice cap and therefore covered with ice.

    The enormous size and nature of Bárðarbunga was not fully recognized until it was observed in 1973 on an image from a satellite, 800 km above Earth (see below). A caldera in the volcano’s crown, 11 km long on the longer side, is covered with approximately 850 m thick glacial ice. Eruptions related to the central volcano can occur anywhere in the caldera, on the sides of the volcano and also in the fissure swarms to the NA and SW of the volcano, for a distance up to 100 km from the central volcano.

    Inevitably, immense eruptions and explosive eruptions are a possibility in the system with imminent threat of ice melting in great magnitude causing a huge jökulhlaup (glacial outburst flood).”

  21. Moderator… is this gibberish, internet slang or spam?

    Thank you for the attention – please delete if inappropriate.

    • The ice flows towards the coast and when it reaches warm (above freezing) water it melts, it also does get above freezing along the edge of the continent in the summer. So there is always some melting going on along the edges, more in the summer. There are also parts of the ice sheets floating on water that will occasionally break off and drift north and melt.

      • Subaerial melting is almost negligible in Antarctica even in summer. Mass-loss is due to calving, and to some extent to sublimation. However some melting occurs below sea-level since salt water will erode ice to some extent even when the water temperature is below zero (which is usually true in Antarctica). Most of the melting takes place well away from the Continent when the icebergs reach warmer waters.
        Note that Iceberg B-9 which Chris Turney blamed for the “ship of fools” fiasco calved 1987 but which has remained close to Antarctica still hasn’t melted after 27 years.

  22. It’s true. This year the water is higher on the sides of my kayak, especially on the same side when I tip slightly to get a better view of it.

  23. If LOD is longer, SLR at the poles will increase, and slow at the equator, relative to each other. No melting required.

  24. If LOD increases, SLR at the poles will increase and at the equator decrease relative to each other. No melting required.

    • After logging into wordpress to post the 5:37 comment, and refreshing this posting, no comment showed, so I re-entered it. Never saw this happen before.

  25. As ever with a lot of the reports being released in the run up to Paris 2015, the words ‘straw’ and ‘clutching’ come to mind.

    • That’s the way it works. I saw a comment a few days ago that was priceless (I can’t remember who wrote it) and to paraphrase for this subject: “They’re using their models to train the measurements.”

  26. Would somebody please explain something to me? How is it possible that water in the Antarctic does not seek to normalize to the global sea level? I would think that sea level would be an indicator of planetary momentum and gravitational influences and continental land elevation changes. How is it that water in the Antarctic ignores these influences and puddles around the south pole? That it does not flow to the equator. Seems to me like a signal drift error or calibration fault, like the error we saw in the ice area satellite output? How does the water know it is in the Antarctic? What am I missing?

    • Antarctica is surrounded by the recently-designated Southern Ocean. It is primarily delineated by the Antarctic Circumpolar Current which links the Atlantic, Pacific, and Indian Ocean basins. It is the largest ocean current, very fast.

      The ACC is strong enough to bring about the recognition of the Southern Ocean as being something separate, and keeps the warmer ocean waters away from Antarctica. The isolation provided by the strong ACC would also allow for this piddly bit of SLR to stay around Antarctica without getting dispersed into those other warmer basins.

      Side note, Our Changing Language: I was going to say piddlesome instead of piddly, meaning triflesome, but spell checker didn’t like it. Google thought I might have meant “meddlesome”, DuckDuckGo only returned results for meddlesome. But Google did find a few usages like with this Staffordshire U. animation student’s blog, showing the word is in use. How many other old words will the technology send to the memory hole in the pursuit of computerized uniformity?

      • Hello kadaka,

        I read your response and thank-you. I am familiar with flow induced boundaries with elevation changes like standing waves at the outlet of the Columbia River on the west coat of the USA and the tidal bore that travels up the Bay of Fundy. The tidal bore in Canada is a transient event. The Coumbia River Standing wave is sustained by steady flow from the river.

        If there is a blister of water atop the south pole, and a hydrodynamic bounday caused by the ACC, then there is an implication that there is huge melting to sustain the flow into the blister, if the event is not transient. But does not Pascals Law prevail? The water can migrate under the ACC?

        Another question stimulated by your response: Could a change in the ACC account for a change in the boundary effects, sufficient to sustain a 2 cm blister?

      • kadaka (KD Knoebel)
        September 1, 2014 at 10:16 am

        … How many other old words will the technology send to the memory hole in the pursuit of computerized uniformity?

        As many as we allow it to. So, oppose the trend. Use the word and let those who don’t know it use a dictionary – a good one, not an on-line version.

  27. An interesting pause in the time-series. However, comparisons of a regional to global have to be on a same-area basis. Furthermore, there are no accounting of the self-gravitational potential of the regional to the global. Therefore, this paper is failed.

  28. The warmists tried ignoring the Antarctic while focusing on the Arctic. Since they are a distracted lot, they had to address the Antarctic ice records with pecking at it with weak studies. In their methods, quantity replaces quality and outcomes so this is considered plugging the (ice) dike.

  29. 350 GT = 350 km3 excess water, so a good deal less than the volume of the smallest Great Lake, Lake Erie, at 480 km3? Only it’s distributed around a continent? Is that significant at all?

  30. What part of winds displace water, do these experts not understand?
    Any boat owner on freshwater lakes knows this.
    I lean toward a Guam Moment, the additional ice must be causing the continent of Antarctica to tip.
    Now that the dishonesty of Team CAGW ™ IPCC is an open secret, Climatology is getting stale.
    However I remain entertained and amused by the speed of the Glibbering Climb Down.
    Seems to be an exponential decay, but there is no hiding the decline in the quality of true believer, I miss their absolute certainty, holier than thou personas and find the current snivelling does nothing to engender any sympathy from me.

  31. Dynamic topography of the souther ocean is very strong and failure to account (ignore) it is a reason to fail this paper.

  32. maybe all the additional ice is weighing down the continent, hence the apparent sea level increase?

    (this comment made half in jest, but it’s at least as coherent as some of the other offerings here. %-)

  33. For the record, Mt. Erebus, located on Ross Island, erupted as recently as 2011, spewing ash. Also, Erebus contains one of the four permanent molten-lava pools on earth. Are we factoring this into our understanding?

  34. Can I ask some newbish amateur questions? Maybe someone will tackle a few of these for me. If so, much obliged.
    (1) if there is increasing sea ice at the Antarctica, won’t that have the effect of raising local sea levels, like dropping ice cubes in a glass? I mean if the ice increases are due to freezing seas, maybe not. But if they are due to increased atmospheric moisture coming into the region, such as from snow, wouldn’t that raise local seas?
    (2) I realize global warming predicts melting ice sheets at the poles. But it seems to me that a warming world would increase ice at the poles, unless the temperatures rose enough where it was above freezing. It seems to me that a warming world will have more moisture in the air. Moisture which will fall as snow in Antarctica, thereby growing the ice sheets.
    (3) if there has been a 17 year pause in warming, why would the Antarctic ice sheets be melting?
    (4) I once read about the complications involved with analyzing sea levels. Continents are moving, sinking, rising. And land is sinking or rising depending on local conditions. The land is rising in many places as it has been since the end of the last ice age when ice pressed the land in. Measuring sea levels seems so complicated and involves so many elaborate considerations and algorithms that only the people making that it requires one to place an inordinate level of trust in the people designing those measurements. Is there any reason I should trust the objectivity of these handful of scientists doing the studies? Are there honest peers checking and duplicating their methods? It seems to me measuring minute levels of sea level rise over a small period of time must have a margin of error that is larger than the claimed increase. And I fear that the value of the bias which is built into these studies is larger than the small increments of sea rise being claimed.

    Thanks!

  35. “The computer model supports our theory…”
    Oh shut up.

    I’ll bet their claims of increased salinity and added fresh water are about as reliable as their model. Not so much.
    Later we’ll find out they never really measured either. That they had made presumptions and theorized (ginned up) the increases.

  36. “Freshwater is less dense than salt water and so in regions where an excess of freshwater has accumulated we expect a localised rise in sea level,”

    Ouch. If the Antarctic ice extent has been increasing during the period studied, then the summer melts put more fresh water in the local region around the Antarctic and so their figure S5 “Regional anomaly in summer (January to April) linear sea level trend, 620 1992-2011, relative to the global barystatic rate of sea level rise” might be explained by this seasonal influx of fresh water.

  37. I wonder if they’ve stuck their fingers into the water and sucked them to check the salinity [there may be more sophisticated measurement methods available these days].

    If the “sea level increase” is due to an influx of fresh water there should be a thin surface layer of water of relatively lower salinity even with mixing etc.

    Or did they just model it ?

  38. The ice ballyhoo seems pretty simple to me.

    According to the national sea and ice center, sea ice extent was 1.03 million square kilometers (398,000 square miles) below the 1981 to 2010 long-term average and 1.42 million square kilometers (548,000 square miles) above that observed in 2012 on the same date.

    At the Antarctic, sea ice remains at a daily record high, and 1.19 million square kilometers (459,000 square miles) above the 1981 to 2010 average.

    So at the poles in total, the extent of ice is currently 61,000 sq miles above the 1981-2010 trend.

    The world is hotter than ever!!!™ and yet there is more ice at the poles than in 30 years.

    GO SANTA!!!

    p.s. which is not to denigrate in any way the fine work of all the elves

  39. Sea level in Antarctic coast increased 2 cm more than Southern Ocean mean. 430 Gt/yr ice mass loss needed to explain sea level rise. GRACE data estimates only 29 to 126 Gt/yr.

    http://www.nature.com/nature/journal/v491/n7425/full/nature11621.html

    The UAH temperature graph shows cooling trend in Antarctica since 1978. How to reconcile all these inconsistencies? Ice water is at 0 Celsius. Specific volume of water at 0 C is greater than at 4 C. If ice water mixes and cools seawater down to 100 meters deep. The volume increase is 2 cm high. The final temperature is > 0 C but ice water adds to the volume.

  40. It is strange that with all this alleged extra global warming in the Antarctic, yet the Southern oceans SST anomaly has been declining since 1981 from about +0.3 C to about -0.2 C as Bob Tisdale’s graphs show every month

    • kevin lenihan (@kevinlenihan1) says: September 1, 2014 at 5:45 pm Can I ask some newbish amateur questions? Maybe someone will tackle a few of these for me. If so, much obliged.
      (1) if there is increasing sea ice at the Antarctica, won’t that have the effect of raising local sea levels, like dropping ice cubes in a glass? I mean if the ice increases are due to freezing seas, maybe not. But if they are due to increased atmospheric moisture coming into the region, such as from snow, wouldn’t that raise local seas?

      ADH – Depends where the sea ice came from. If from freezing the sea water, should be no change, the ice floes will occupy the same amount of space below sea level as they would if melted. Straightforward Archimedes. If the ice has slid off the land, the sea level will rise, but this will be a temporary rise as the excess water will flow north to equalize sea levels.

      (2) I realize global warming predicts melting ice sheets at the poles. But it seems to me that a warming world would increase ice at the poles, unless the temperatures rose enough where it was above freezing. It seems to me that a warming world will have more moisture in the air. Moisture which will fall as snow in Antarctica, thereby growing the ice sheets.

      ADH The temperature inland in Antarctica is so low that absolute humidity is exceedingly low. Hardly any extra snow will be deposited (hence the great age available in ice cores – not enough new snow to melt the bottom layer). But at the edge, where sea water and ice exist, the temperature will for part of the year be above freezing, and there will be greater humidity, and it is plausible that snow/sleet/rain will fall and be frozen on contact with very cold ice, and there may be more ice created than is destroyed.

      (3) if there has been a 17 year pause in warming, why would the Antarctic ice sheets be melting?

      ADH It all depends on what happens at the edge, where the sea is in contact with the ice. Sea water is above freezing point so there will be a tendence for ice to melt. There will also be a tendency for water to freeze. Reduce the speed of the ocean currents, more likely that the ice will freeze the near stationary water. Increase the speed of the currents, the cold water will be replaced by more cold water, and it will be more likely that the ice will melt.

      (4) I once read about the complications involved with analyzing sea levels. Continents are moving, sinking, rising. And land is sinking or rising depending on local conditions. The land is rising in many places as it has been since the end of the last ice age when ice pressed the land in. Measuring sea levels seems so complicated and involves so many elaborate considerations and algorithms that only the people making that it requires one to place an inordinate level of trust in the people designing those measurements. Is there any reason I should trust the objectivity of these handful of scientists doing the studies? Are there honest peers checking and duplicating their methods? It seems to me measuring minute levels of sea level rise over a small period of time must have a margin of error that is larger than the claimed increase. And I fear that the value of the bias which is built into these studies is larger than the small increments of sea rise being claimed.

      ADH Very complicated in NW Europe, Canada and the USA, which were all subjected to glaciations, and the ‘solid’ crust is bouncing up and down – albeit very slowly. Antarctica has been glaciated for millions of years, there should be negligible uplift or sinking of the crust there, apart from in the volcanic areas. So simple tide gauges should suffice. However, SFAIK, the data from satellites re sea levels is available to all ‘scientists’ who are interested in sea levels, and not all are weeded to the CAGW religion. So when someone writes a paper, others read it and if it looks wrong, they may check, if they have time. So while not necessarily ‘peer reviewed’ in the usual sense, it is unlikely that really bad errors will be made, and not picked up. As to what margins of error there may be, this should be stated in the paper. If not, beware!!!!!

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