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Why remote Antarctica is so important in a warming world

Posted on 21 February 2018 by Guest Author

Chris Fogwill, Professor of Glaciology and Palaeoclimatology, Keele University; Chris Turney, Professor of Earth Sciences and Climate Change, UNSW, and Zoe Robinson, Reader in Physical Geography and Sustainability/Director of Education for Sustainability, Keele University

This article was originally published on The Conversation. Read the original article.

Ever since the ancient Greeks speculated a continent must exist in the south polar regions to balance those in the north, Antarctica has been popularly described as remote and extreme. Over the past two centuries, these factors have combined to create, in the human psyche, an almost mythical land – an idea reinforced by tales of heroism and adventure from the Edwardian golden age of “heroic exploration” and pioneers such as Robert Falcon Scott, Roald Amundsen and Ernest Shackleton.

Recent research, however, is casting new light on the importance of the southernmost continent, overturning centuries of misunderstanding and highlighting the role of Antarctica in how our planet works and the role it may play in a future, warmer world.

Heroic exploration, 1913. wiki

What was once thought to be a largely unchanging mass of snow and ice is anything but. Antarctica holds a staggering amount of water. The three ice sheets that cover the continent contain around 70% of our planet’s fresh water, all of which we now know to be vulnerable to warming air and oceans. If all the ice sheets were to melt, Antarctica would raise global sea levels by at least 56m.

Where, when, and how quickly they might melt is a major focus of research. No one is suggesting all the ice sheets will melt over the next century but, given their size, even small losses could have global repercussions. Possible scenarios are deeply concerning: in addition to rising sea levels, meltwater would slow down the world’s ocean circulation, while shifting wind belts may affect the climate in the southern hemisphere.

In 2014, NASA reported that several major Antarctic ice streams, which hold enough water to trigger the equivalent of a one-and-a-half metre sea level rise, are now irreversibly in retreat. With more than 150m people exposed to the threat of sea level rise and sea levels now rising at a faster rate globally than any time in the past 3,000 years, these are sobering statistics for island nations and coastal cities worldwide.

An immediate and acute threat

Recent storm surges following hurricanes have demonstrated that rising sea levels are a future threat for densely populated regions such as Florida and New York. Meanwhile the threat for low-lying islands in areas such as the Pacific is immediate and acute.

image Much of the continent’s ice is slowly sliding towards the sea. R Bindschadler / wiki

Multiple factors mean that the vulnerability to global sea level rise is geographically variable and unequal, while there are also regional differences in the extremity of sea level rise itself. At present, the consensus of the IPPC 2013 report suggests a rise of between 40 and 80cm over the next century, with Antarctica only contributing around 5cm of this. Recent projections, however, suggest that Antarctic contributions may be up to ten times higher.

Studies also suggest that in a world 1.5-2°C warmer than today we will be locked into millennia of irreversible sea level rise, due to the slow response time of the Antarctic ice sheets to atmospheric and ocean warming.

We may already be living in such a world. Recent evidence shows global temperatures are close to 1.5°C warmer than pre-industrial times and, after the COP23 meeting in Bonn in November, it is apparent that keeping temperature rise within 2°C is unlikely.

So we now need to reconsider future sea level projections given the potential global impact from Antarctica. Given that 93% of the heat from anthropogenic global warming has gone into the ocean, and these warming ocean waters are now meeting the floating margins of the Antarctic ice sheet, the potential for rapid ice sheet melt in a 2°C world is high.

In polar regions, surface temperatures are projected to rise twice as fast as the global average, due to a phenomenon known as polar amplification. However, there is still hope to avoid this sword of Damocles, as studies suggest that a major reduction in greenhouse gases over the next decade would mean that irreversible sea level rise could be avoided. It is therefore crucial to reduce CO? levels now for the benefit of future generations, or adapt to a world in which more of our shorelines are significantly redrawn.

This is both a scientific and societal issue. We have choices: technological innovations are providing new ways to reduce CO? emissions, and offer the reality of a low-carbon future. This may help minimise sea level rise from Antarctica and make mitigation a viable possibility.

Given what rising sea levels could mean for human societies across the world, we must maintain our longstanding view of Antarctica as the most remote and isolated continent.

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Comments 1 to 11:

  1. "...major reduction in greenhouse gases", "...reduce CO₂ levels now...", " ways to reduce CO₂ emissions...".

    Wiggly wormy weasle words that muddle the truth. 

    "technological innovations are providing new ways to reduce CO₂ emissions...".

    There are currently none that have any prospect what so ever at scaling to a degree that is even 1% of what will be necessary, but don't let that stand in the way of "magic happens aka technology".

    "...a low-carbon future."

    Which is it, negative carbon/removing carbon in massive giga, trillion, mega amounts, or just lower?

    What is needed is speaking truth to the masses. Difficult? hell yes, but absolutely good will happen until we take on that herculean task first.

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  2. jef @1

    "...major reduction in greenhouse gases", "...reduce CO₂ levels now...", " ways to reduce CO₂ emissions..."."Wiggly wormy weasle words that muddle the truth."

    They don't muddle the truth, because the language is clear enough and is based on what we know is possible. You also don't explain why you think the statements in the article muddle the truth, so you are just posting empty propaganda.

    "technological innovations are providing new ways to reduce CO₂ emissions..."."There are currently none that have any prospect what so ever at scaling to a degree that is even 1% of what will be necessary, but don't let that stand in the way of "magic happens aka technology"

    You give no evidence that these things can't be scaled up. Theres no technical reason because the technology exists. The only thing standing in the way is perhaps human motivation, but people have found the will in the past to tackle major projects. Of course nobody said it would be easy. Where does the article say it would be easy? So you are just posting empty cynicism.

    Of course one other thing standing in the way are campaigns of climate science denialism and also attacks on renewable energy, mainly from self promoting lobby groups. Maybe have a look in the mirror?

    "...a low-carbon future."Which is it, negative carbon/removing carbon in massive giga, trillion, mega amounts, or just lower?"

    The article said low carbon, so presumably they mean low carbon. Humanity will always use fossil fuels for things like plastic manufacture, had you not thought of that?

    "What is needed is speaking truth to the masses. Difficult? hell yes, but absolutely good will happen until we take on that herculean task first.'

    Yes, and you are not communicating anything very well to the masses,  because you make wild, one sided, unsupported, cynical claims.

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  3. The language is far from clear. Broad generalizations completely without reference (the onus is on the authors of the article not me).
    Simply stating there is a problem then saying we need to ...oh I don't know... make it less of a problem?
    It is a life threatening catastrophe that requires massive world wide action NOW!
    Where is the attribution to successful beccs operations that show the potential to scale…none. I have personally worked on several biofuel, syngas, biochar, and other projects alongside university efforts over the last 10 to 15 years and none of them are still active, all were essentially failures or a net wash at best. In other words as much is saved as is generated.
    Most if not all “renewable” energy is 100% dependent on FFs. They are a FF extender at best.
    Oh plastics… yes thats not a problem is it?
    So yes… magical thinking/technocopianism. You sir are the problem not the solution. We need real solutions not just a slight adjustment of the dial.

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  4. jef @ 3

    I think your criticism of BECCS and some of the other ‘schemes’ you have come across is quite right. You may be interested in my comment here.

    You sound very frustrated that their isn’t an instant cure to halt global warming. Well, there isn’t!  But there are ways of significantly reducing our greenhouse gas emissions, such as transitioning away from coal fired electricity generation (in progress) electrification of transport (in progress) and increasing the efficiency with which we use electricity (also in progress).

    I know they are not overnight cures but they are among several effective ways of reducing emissions. Over the coming decade you will see them beginning to work. We need to do more and I believe we will – because if we don’t?   Well, as they say, ‘nothing concentrates the mind so much as the prospect of being hanged’.

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  5. Jef @3

    I dont see where your lack of clarity is. The "article" is actually mostly on Antarctic ice loss, and the considerable dangers of this. You are missing this fundamental point. You claim its got no references, but its full of links.

    I dont really know what you are referring to on technology. Theres a link to something on blended hydrogen, but its hardly the main point of the article. You seem a little off topic to me.

    You say " I have personally worked on several biofuel, syngas, biochar, and other projects alongside university efforts over the last 10 to 15 years and none of them are still active, all were essentially failures or a net wash at best. In other words as much is saved as is generated."

    Your claims of experiments are not compelling and are anecdotal. Provide a link so I can check. We have a highly profitable synthetic methanol plant in my country and biofuels are actually quite well established now.

    "Most if not all “renewable” energy is 100% dependent on FFs. They are a FF extender at best."

    Only in their production, and studies show they reduce CO2 over time. Refer below.

    You sir just post a lot of claims, but not much in the way of peer reviewed analysis, or something from a recognised mainstream science magazine to back it up.

    Like Riduna says there are ways of reducing emissions significantly, and that is whats important. I have mixed thoughts about BECCS, and I posted something on some other article recently. The best negative emissions systems appear to be tree planting and soil sequestration of carbon. Soil sequestration can certainly be scaled up in physical terms, its mainly a question of relatively simple changes to farming techniques, incentives and education. 

    Regarding the antarctic (the actual point  of the article) there are a lot of issues pointing at possibility of more rapid sea level rise than currently anticipated. I dont like the sheer number of possible problems when you combine the antarctic and greenland etc. This suggests use of the precautionary principle.

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  6. NASA's Operation Icebridge... Please Google it and then ask yourself why a search of Skeptical Science has no mention of the on going definitive research that now shows the overall increase in Antarctica ice. One would think this would be at least worth a mention... Right?

    PS I have a BS in physical science, a MBA and I'm working on my PhD in planetary geology. I'm NOT a warming denier I'm just convinced CO2's role has been overblown and like the proverbial squirrel, we have taken our eye off the ball and should be helping a billion plus people in the developing world live better lives and stop polluting our little blue ball.

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    Moderator Response:

    [TD] Entering "Operation Icebridge" in the SkepticalScience Search field at the top left of every page reveals several hits. So what? Googling yields a bunch of hits, at least the first dozen of which fail to even hint at any "definitive research that now shows the overall increase in Antarctica ice." But there is a very informative page that should be comprehensible to someone who is "working on" a PhD in planetary geology.

    Entering "Antarctic" in the Skeptical Science search field yields many hits, including a response to the myth "Antarctica is gaining ice."

    Perhaps you are fixated on Zwally's 2015 paper. A more recent (July 2017) Scientific American article describes more recent research than that particular Skeptical Science post does, explaining that most scientists who study Antarctic land ice believe that its net is loss, not gain. Perhaps even Zwally:

    Zwally's study team claimed that if mass losses in West Antarctica continued to increase, it would only be a few decades before they overtook the gains in the east. Also, the team has additional, unpublished data showing the mass losses in West Antarctica have not only increased, but have tripled—at least from 2009 to 2012. Early data show 2016 might have been the tipping point at which losses in West Antarctica became so great that they equaled those gains in East Antarctica. That means Zwally's results might already be in agreement with others on the key point: this frigid land—one that holds the fate of much of humanity—is melting.

    A sincere word of advice from someone who's already gotten a natural science PhD: If you really are working on a PhD in planetary geology, you need to search the literature more thoroughly and critically, and synthesize what you find. PhD quality work is a big step up from BS quality work.

  7. "the overall increase in Antarctica ice"

    Zwally et al 2015 took an unconventional approach to assessing the mass balance of Antarctica. Unlike other studies, before and since, that used satellite altimetry or satellite gravimetric methods, Zwally’s team chose to compare net snowfall accumulation to estimated ice discharge to the ocean. In order to do this type of analysis properly, 3 main things are needed:

    1. It is critical to use the most optimal corrections for instrument biases (the ICESat data used need to have the appropriate saturation bias corrections to get real-world answers that are reproducible)
    2. The most-accurate densities of snow have to be used
    3. The most-optimal values for changes in bedrock elevation (GIA) in response to ice sheet mass changes have to be used

    As has been since determined by multiple studies (A, B, C and D, listed following):

    1. The ICESat bias corrections used by the Zwally team were appropriate for measuring sea ice, but not for measuring high altitude land-base ice sheets like found in Antarctica (the values returned for Lake Vostok alone were so unphysical that they should have made the entire study DOA)
    2. A value for snowfall density different than that determined by decades of land-based research was used
    3. The values used by the Zwally team to correct for GIA were too high by a factor of 2

    As such, their results cannot be reproduced using well-established bias corrections, known snow densities and more appropriate values for GIA.

    The values for the Antarctic ice sheet mass balance from NASA GRACE are the most current available (to January 2017). An ever-strengthening, consilient body of research using multiple methods all point to that conclusion.

    Reference studies:

    A. Scambos et al 2016 Comment on Zwally et al 2015

    B. Martín-Español et al 2016 - Spatial and temporal Antarctic Ice Sheet mass trends, glacio-isostatic adjustment, and surface processes from a joint inversion of satellite altimeter, gravity, and GPS data

    C. Schröder et al 2017 - Validation of satellite altimetry by kinematic GNSS in central East Antarctica

    D. Martín-Español et al 2017 - Constraining the mass balance of East Antarctica

    Interestingly, previous research has shown that ice sheet mass contributions from land-based ice sheets have exceeded thermal expansion as the biggest contributor to global sea level rise. Recent research now has isolated the individual ice sheet contributions to global sea level rise.

    Per Hsu and Velicogna 2017, between April 2002 and October 2014, the mass component of global mean sea level grew by about 1.8 millimeters per year, with 43 percent of the increased water mass coming from Greenland, 16 percent from Antarctica, and 30 percent from mountain glaciers. There is an additional ~1 mm per year of SLR coming from thermal expansion (H/T to Victor Zlotnicki).

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  8. @jef, I agree with your critiques of this article’s advancement of both reducing atmospheric carbon levels now, while also encouraging a low-carbon future, which it does without an inclusion of how individuals or groups might take action. You are absolutely correct in saying that what is needed is truth speaking to the masses, which is a “herculean task,” yet should be of utmost importance given climate change’s immediacy. The article discusses Antartica’s importance in being a reservoir of 70% of our world’s freshwater, with melting ice sheets and the resultant sea rise posing great danger to over 150 million people globally. Unfortunately, climate change is not at all fair, having perverse asymmetry of impacts and interests, meaning those who contribute the least are often impacted the most. The article alludes to this by describing the potential future threat to populated areas such as Florida and New York, but the “immediate and acute” threat small low-elevation islands are already facing, such as the Pacific Island Countries (PICs). Due to their fragile environments and often unstable economies, island nations tend to struggle greatly at bouncing back after a devastating natural disaster, for they simply do not have the resources to be resiliently reactive. Ten years ago, the World Bank created the Pacific Catastrophe Risk Assessment and Financing Initiative (PCRAFI) in order to establish risk assessment strategies, while developing pragmatic financial and technical applications to try and mitigate these islands’ susceptibility to disasters. As a prominent global development organization, The World Bank has an interest in lessening poverty seen around the world via sustainable solutions; but if major contributors to climate change are not working to lessen their carbon footprints, will such mitigation strategies truly be effective?

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    ^World Bank article I referenced in previous post.

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  10. jclairea @8

    Good point. Pacific island nations get a double whammy. Serious sea level rise, stronger tropical cyclones, water salination problems, lack of resources.

    I also see what you are doing there. Demolishing his comments with niceness.

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  11. fishfear.

    What you think is irrelevant in this context, what is relevant is what you can demononstrate with evidence. So accusing Skeptical Science of bias is intellectually dishonest. I could go on about your use of rhetorical questions and sloganeering, but I think I have made my point.

    You can demonstrate your appeal to your own authority by posting citations to your publications easily enough.

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