Scientists find Antarctic ice is melting faster

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The summer ice melt in parts of Antarctica is at its highest level in 1,000 years, Australian and British researchers reported on Monday, adding new evidence of the impact of global warming on sensitive Antarctic glaciers and ice shelves.


Researchers from the Australian National University and the British Antarctic Survey found data taken from an ice core also shows the summer ice melt has been 10 times more intense over the past 50 years compared with 600 years ago.

"It's definitely evidence that the climate and the environment is changing in this part of Antarctica," lead researcher Nerilie Abram said.

Abram and her team drilled a 364-metre (400-yard) deep ice core on James Ross Island, near the northern tip of the Antarctic Peninsula, to measure historical temperatures and compare them with summer ice melt levels in the area.

They found that, while the temperatures have gradually increased by 1.6 degrees Celsius (2.9 degrees Fahrenheit) over 600 years, the rate of ice melting has been most intense over the past 50 years.


continue to source article at reuters.com

18 COMMENTS

  1. This is serious.
    Much of West Antarctica has ice going down to below the present sea level, so if sea-levels rise with melt-water or if warmer currents of salt water get under the icecaps and float the ice off the land below: – the west of the Antarctic “Continent”, could be come a group of islands.
    This would lead to a very rapid break-up of the ice caps and a further increase in rate of rise in sea levels.

  2. In Scientific American there was an article, stating that just stopping green house gas emissions won’t help anymore. We will need geo-engineering to stop it, something that has never been done before.

    • In reply to #2 by nlib1:

      In Scientific American there was an article, stating that just stopping green house gas emissions won’t help anymore. We will need geo-engineering to stop it, something that has never been done before.

      I think its wrong to talk about “stopping” global climate change as if it was a binary switch that was either one or zero. Its not. Its a continuous process. I take it as a given that it can’t be stopped. Its happening and its going to keep on happening in the near term future at least. Talking about whether or not we can “stop” it fits into denialist rhetoric. I actually predicted this many years ago, that the next stage after climate deniers couldn’t keep denying was to say “well yes its real and we caused it but its too late to do anything now”

      The question isn’t can we stop it but how to react to it? Its not a question of whether the climate will change, it has and will continue to do so. The question is are we going to start getting serious about taking real steps from stopping the climate change from being the worst it could be and to give us a chance to eventually even reverse it?

      I’ve read some of the descriptions of these ideas to Teraform the Earth and they scare the crap out of me. One of the first thing you learn as an engineer is that things almost never work in the real world the way they do in the lab and since we only have one Earth we need to stop doing science experiments on it.

      • In reply to #3 by Red Dog:

        I’ve read some of the descriptions of these ideas to Teraform the Earth and they scare the crap out of me. One of the first thing you learn as an engineer is that things almost never work in the real world the way they do in the lab and since we only have one Earth we need to stop doing science experiments on it.

        I agree!
        Most of the so called “engineering solutions”, are ludicrously pathetic in terms of scale, and utterly clueless about the environmental and climatic side-effects of their proposals. Many of them are just denialist excuses for prevarication.

    • In reply to #2 by nlib1:

      We will need geo-engineering to stop it, something that has never been done before.

      We can block out the freakin’ sun if have to. We’re humans. We’re awesome. The global ban on CFCs during the Cold War demonstrates a political apparatus can exist for emergency geo-engineering, and there are many technical tools at our disposal. We can do it with contrails, or The Mad Scot Plan, which while completely mad has it’s allure.

    • In reply to #2 by nlib1:

      In Scientific American there was an article, stating that just stopping green house gas emissions won’t help anymore. We will need geo-engineering to stop it, something that has never been done before.

      Interestingly enough there are several depressions around the world which if allowed to flood would absorb around 2 meters of sea level rise. (Dead Sea -427 meters, Qattara Depression -133, Afar Depression -155, Lake Eyre -15, Death Valley -86 (hard to connect), Salton Sea -66 (redirect rivers permanently), Laguna del Carbón -105, Bajo del Gualicho -72, Salina Grande and Salina Chica -42) Every meter of flooding into the depression removes a fraction of a meter of sea level rise, but some of these depressions could flood to quite deep depths before effecting substantial populations.

      Of course such flooding would destroy some extreme habitats but the engineering is not impossible and could save millions of lives and low areas from flooding. If the sea rise threatens to cause 15+trillion in damages and the flood engineering works cost 15 billion then it is economically sensible. As an emergency engineering solution it makes some sense, It would though be disappointing to destroy some very unique environments.

      There are some pretty old, odd engineers and colonialists who would be happy to have some of their 18th Century dreams come true even if it is for save the world reasons.

      • In reply to #16 by ozkrenske:

        The problem with this, as with all large geo-engineering notions, is that it does not take into account side effects such as the ocean acidification I mentioned and linked @11, or the feed-back effects such as reduced albedo due to polar ice-loss, methane releases, or peat and forest fires caused by a hotter drier climate in some areas.

        That is not to say that we may adopt such measures as acts of desperation at some time in the future, but they could well make matters worse – especially if they are politically accepted as substitutes for more appropriate actions to reduce CO2 emissions and levels.

  3. There are a number of things that have flipped us into positive (runaway) feedback such as the release of methane by melting permafrost and change of albedo by reduced polar ice and Greenland surface melt. Nothing we can do at this time will stop the warming, we can only take steps to try to slow it down.

  4. At the risk of sounding like a climate change denier (although I’m really just a skeptic and scientist)…
    Doesn’t the line “The summer ice melt in parts of Antarctica is at its highest level in 1,000 years” imply that it was greater than or equal to the current level over 1000 years ago…?

    • In reply to #7 by Prime8:

      At the risk of sounding like a climate change denier (although I’m really just a skeptic and scientist)…
      Doesn’t the line “The summer ice melt in parts of Antarctica is at its highest level in 1,000 years” imply that it was greater than or equal to the current level over 1000 years ago…?

      No, when I was 15 I was taller than I had been in 10 years. Of course you can go back 100s of millions of years when the continents were in different places and what is now Antarctica was tropical, but that is not relevant. Looking at the last 1000 years is simply putting it in a context where natural conditions have been relatively constant, and humans have been increasingly putting carbon into the atmosphere.

  5. Climate contrarians, for want of a neutral term, have long said, “well, if the world is warming, why is the Antarctic ice growing?” It hasn’t been doing that, by the way. But if even Antarctica is experiencing accelerating melting (something that was hard to bring about, for several reasons), they’re screwed, as is the world in general.

    nlib1

    just stopping green house gas emissions won’t help anymore. We will need geo-engineering to stop it, something that has never been done before

    Well, there are many opinions on what will be necessary, sufficient or sensible. Most experts on geo-engineering think it’s not a risk worth taking. (For example, if you pull carbon dioxide out of the atmosphere too quickly, it could cause disastrous increases in rainfall.) But the longer we go doing basically nothing, the less truth that view will have.

    Quine

    There are a number of things that have flipped us into positive (runaway) feedback

    Those aren’t synonymous. There are various reasons warming begets more warming, e.g. it evaporates oceanic greenhouse gases into the atmosphere. However, since 1+1+1+… is infinite while 1+1/2+1/4+…=2, some positive feedback isn’t runaway feedback. Indeed, it doesn’t seem likely Earth’s climate will experience runaway feedback any time soon. Climate contrarians sometimes pretend this means the feedback is zero or negative, so they can downplay the climate sensitivity. It doesn’t mean that at all.

    Nothing we can do at this time will stop the warming, we can only take steps to try to slow it down

    Carbon dioxide draw-down could (but I mentioned above a reason that could be bad).

    Prime8

    At the risk of sounding like a climate change denier (although I’m really just a skeptic and scientist)

    What kind of scientist? I hope your skepticism means belief in proportion to evidence rather than general doubt of the consensus.

    Doesn’t the line “The summer ice melt in parts of Antarctica is at its highest level in 1,000 years” imply that it was greater than or equal to the current level over 1000 years ago…?

    All it necessarily means is, “We know what the last 1000 years is like, and this breaks records in that data range”. They might not know the summer ice melt record accurately enough to say when, if ever, the ice melt was last this fast or faster. However, “about 1000 years ago it was even more extreme than this, so we’re safe”, is a common bad argument contrarians use. It usually involves cherry-picking data to find the few examples of recent similarities, overlooking (for example) our now having the most acidic oceans in 300 million years. It also overlooks the fact that most present changes are happening at a rate that’s highly unusual in Earth’s history, that we know (as certainly as we can know anything about the future) from physical laws that the changes will accelerate further if our emissions continue with business as usual, and changes this rapid are either unheard of or pretty much confined to mass extinction events. (Incidentally, all but one of Earth’s mass extinction events involved carbon dioxide playing the same game it’s playing today.)

    • In reply to #9 by Jos Gibbons:

      It usually involves cherry-picking data to find the few examples of recent similarities, overlooking (for example) our now having the most acidic oceans in 300 million years.

      A lot of people are not aware of the consequences of ocean acidification. Pictures 2 and 3 on this link might help clarify their understanding.

      http://ngm.nationalgeographic.com/2011/04/ocean-acidification/liittschwager-photography

      Picture 2:-

      At Castello Aragonese, a volcanic island off Naples, Italy, healthy seafloor looks like this: a lumpy quilt of red sponges, white barnacles, lilac coralline algae, sea urchins, and (near the center of the photograph) one well-camouflaged fish. It’s a tompot blenny.

      Picture 3

      A few hundred yards from the preceding scene, CO₂ bubbling from seafloor vents acidifies the water to levels that might one day prevail all over the oceans. Dull mats of algae replace the colorful diversity—”fair warning,” says biologist Jason Hall-Spencer.

      @ Jos:-

      It also overlooks the fact that most present changes are happening at a rate that’s highly unusual in Earth’s history, that we know (as certainly as we can know anything about the future) from physical laws that the changes will accelerate further if our emissions continue with business as usual, and changes this rapid are either unheard of or pretty much confined to mass extinction events. (Incidentally, all but one of Earth’s mass extinction events involved carbon dioxide playing the same game it’s playing today.)

      For those looking for details, your earlier discussion has much info:-
      http://old.richarddawkins.net/discussions/642733-why-the-laws-of-physics-make-anthropogenic-climate-change-undeniable

    • In reply to #9 by Jos Gibbons:

      Quine

      There are a number of things that have flipped us into positive (runaway) feedback

      Those aren’t synonymous. There are various reasons warming begets more warming, e.g. it evaporates oceanic greenhouse gases into the atmosphere. However, since 1+1+1+… is infinite while 1+1/2+1/4+…=2, some positive feedback isn’t runaway feedback. Indeed, it doesn’t seem likely Earth’s climate will experience runaway feedback any time soon. Climate contrarians sometimes pretend this means the feedback is zero or negative, so they can downplay the climate sensitivity. It doesn’t mean that at all.

      Please note that I put the word “runaway” in parenthesis, and did not specify equivalence. I put that in because when I typically discuss this with people they take the word “positive” as “good for us” instead of in the engineering servo dynamic sense. So when I do talk to friends and neighbors about this, I suggest the connection to runaway feedback to be sure to give folks the right context. Now, actual runaway feedback does happen in real systems. It does not happen for an infinite amount of time because real systems always hit limits, as has the greenhouse effect on Venus. We are currently experiencing increasing levels of positive feedback, and don’t know when that feedback will stop increasing.

      Nothing we can do at this time will stop the warming, we can only take steps to try to slow it down

      Carbon dioxide draw-down could (but I mentioned above a reason that could be bad).

      We have no means of draw-down at this time that can match the tonnage of carbon coming out of the environment, and the increased heat retention by changing albedo. We can start building that, which might slow things down for the future, but can’t stop the warming now. If you know a practical draw-down plan that would hit balance in the next year, I would like to hear about it.

    • In reply to #9 by Jos Gibbons:

      Prime8

      At the risk of sounding like a climate change denier (although I’m really just a skeptic and scientist)

      What kind of scientist? I hope your skepticism means belief in proportion to evidence rather than general doubt of the consensus.

      Doesn’t the line “The summer ice melt in parts of Antarctica is at its highest level in 1,000 years” imply that it was greater than or equal to the current level over 1000 years ago…?

      All it necessarily means is, “We know what the last 1000 years is like, and this breaks records in that data range”. They might not know the summer ice melt record accurately enough to say when, if ever, the ice melt was last this fast or faster. However, “about 1000 years ago it was even more extreme than this, so we’re safe”, is a common bad argument contrarians use. It usually involves cherry-picking data to find the few examples of recent similarities, overlooking (for example) our now having the most acidic oceans in 300 million years. It also overlooks the fact that most present changes are happening at a rate that’s highly unusual in Earth’s history, that we know (as certainly as we can know anything about the future) from physical laws that the changes will accelerate further if our emissions continue with business as usual, and changes this rapid are either unheard of or pretty much confined to mass extinction events. (Incidentally, all but one of Earth’s mass extinction events involved carbon dioxide playing the same game it’s playing today.)

      Jos,
      My question was not to deny climate change or to show support of the science denialist culture in general, I just try to read everything with an open and curious mind. Let’s admit it, if this article had the opposite conclusion, but the same “last 1000 years” line in it, we would all be up in arms about how they were weasel wording to exclude data that didn’t support their hypothesis. I was merely asking the question to determine why 1000 was the timescale they chose. I am not a climate change denier, and have been trying to gather as much factual, relevant data as I can to combat my conservative step father who works as a oil and gas geologist and is a fervent denier of human-caused climate change. I must say though that gathering empirical data from trustworthy sources has been a chore, as there doesn’t seem to be a whole lot of conclusive publications yet to shove in his face. So, maybe if someone could point me in the right direction…

      As far as scientist, maybe “applied scientist” would have been a better term. I have my bachelors and masters in Materials Engineering and work as a metallurgist. I would definitely refer to myself as a “life scientist” though, as i read this site and Coyne’s site daily during lunch, read books on evolutionary biology (Dawkins, Coyne, Shubin, etc…), and choose to decorate my house in mostly science-based artwork. In college I took a Human Genetics and a Genomics grad course as my 2 science electives because that’s what interested me.

      • Prime8, have you seen skepticalscience.com? That gives a pretty good all-in-one-place summary of the science. Some of its articles pull together many things to identify what has been found in general, while other articles discuss specific examples in detail, so it does a bit of each. It also has something similar to the Talk.Origins Index to Creationist Claims; it explains, with varying (often customisable) levels of detail, what’s scientifically wrong with the denier arguments. It also updates several times weekly. You might well find it helpful.

  6. Procrastination saves you a lot of work. You wait until the need is pressing before taking action. Much of the time situations change and you may not need to take action. However this strategy is lethal in dealing with global warming. If you wait until the results are painful, it is far too late to take action. The earth has astounding inertia. For now that inertia is protecting us. Later it will prolong the punishment of our descendants for our crimes.

  7. Some old Nimbus satellite film canisters have been found and digitised to produce early maps of ice cover.

    Earliest satellite maps of Antarctic and Arctic sea-icehttp://www.bbc.co.uk/news/science-environment-22271972

    The NSIDC project examined almost 40,000 images from the Nimbus-1 archive to produce the September 1964 maps of Arctic (L) and Antarctic (R) sea-ice extent.

    Regular mapping from space did not begin until 1978.

    ▬▬▬▬▬▬▬▬ ▬▬▬▬▬▬▬▬ ▬▬▬▬▬▬▬▬

    The research shows, for example, that sea-ice extent in the Antarctic in 1964 reached at least 19.7 million sq km.

    That is greater than anything seen in the continuous 1979-2012 data-set – larger even than the “record” extent of 19.44 million sq km achieved last year.

    ▬▬▬▬▬▬▬▬ ▬▬▬▬▬▬▬▬ ▬▬▬▬▬▬▬▬

    The analysis produced a summer Arctic sea-ice minimum extent of 6.9 million sq km. This is broadly similar to the 1979-2000 average of 7.04 million sq km observed by modern satellites, and the number used to judge current behaviour in the Arctic.

    Recent years have witnessed a dramatic decline in both volume and extent, with the 2012 coverage – like the Southern Hemisphere – setting a “record” for the modern era at 3.41 million sq km.

    Data from Nimbus-2 and -3, covering 1966 to 1972, is now being investigated.

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