An event similar to one 15,000 years ago is blamed on global warming today

From the University of New South Wales. The logic here seems a bit muddled. If this event where migration of westerly winds towards the south pole happened 15,000 years ago, what makes them think that it happening again now is due to global warming?

Global warming endangers South American water supply

Tuesday, July 29: Chile and Argentina may face critical water storage issues due to rain-bearing westerly winds over South America’s Patagonian Ice-Field to moving south as a result of global warming.

A reconstruction of past changes in the North and Central Patagonian Ice-field, which plays a vital role in the hydrology of the region, has revealed the ice field had suddenly contracted around 15,000 years ago after a southerly migration of westerly winds.

This migration of westerly winds towards the south pole has been observed again in modern times and is expected to continue under a warming climate, likely leading to further ice declines in this area affecting seasonal water storage.

“We found that precipitation brought to this region by Southern Hemisphere westerlies played an important role in the glaciation of the North Patagonian Ice-Fields,” said Dr Chris Fogwill from the Climate Change Research Centre at the University of New South Wales.

“Our research has shown this ice-field significantly reduced in size when those winds moved southwards.”

The North Patagonian Ice-field is vital to maintain seasonal water storage capacity for Argentina and Chile.

“Worryingly, this study suggests the region may well be on a trajectory of irreversible change, which will have profound impacts on agriculture and the increasing dependency on hydroelectric power in Chile and Argentina,” Dr Fogwill said.

The team revealed the importance of the winds on the ice-sheets and consequent water supply by using rare isotopes to uncover changes in the ice-sheet thickness since the last major glaciation. This revealed the decline in the ice-sheet between 15,000 to 19,000 years ago.

Using a separate collection of ocean cores they were then able to determine that this decline coincided with the movement southwards of the westerlies.

The researchers found that a lack of precipitation caused by this movement, coupled with additional warming caused by rapid ice loss saw a sharp decline in glaciers with no seasonal recovery.

Interestingly, the southern part of the ice-field did not appear to be impacted by the movement of these winds. Instead it appeared that ocean currents and temperatures played a more important role in maintaining the ice in this section.

“The ice-field in the Northern and Central region of the Patagonian ice-field are highly sensitive to precipitation and need this to remain healthy,” said Dr Fogwill.

###

Paper: Rapid thinning of the late Pleistocene Patagonian Ice Sheet followed migration of the Southern Westerlies (DOI: 10.1038/srep02118)

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59 thoughts on “An event similar to one 15,000 years ago is blamed on global warming today

  1. There’s that word again – “irreversible”. It should never be used with respect to climate.

    The rest of the article reproduced above *is* muddled, uses emotive language, and offers no explanation as to why this happened before (at least they didn’t say “unprecedented”).

  2. Another evidence of ignorance… These guys should read Leroux and understand what’s really happening, and it is NOT warming. The repeated cold waves for many years now affecting South America debunk their preposterous, attention grabing garbage.

  3. Anthony Watts posted: “From the University of New South Wales. The logic here seems a bit muddled. If this event where migration of westerly winds towards the south pole happened 15,000 years ago, what makes them think that it happening again now is due to global warming?”

  4. “The North Patagonian Ice-field is vital to maintain seasonal water storage capacity for Argentina and Chile.”

    Surely this was the intended reason for the formation of this ice-field.

  5. I can’t help but think the only possible solution for this leftist horror claptrap is to destroy world economies and rush pell-mell back to the stone age. Don’t get in my way, people!
    /snarc

  6. Did you read the new report that 1700 cities will be underwater by end of century, 80 by end of decade? Good grief, these idiots are really becoming unhinged now, aren’t they?

  7. Jorge says:
    July 30, 2013 at 9:35 am

    Did you read the new report that 1700 cities will be underwater by end of century, 80 by end of decade? Good grief, these idiots are really becoming unhinged now, aren’t they?

    They feel that they have to get all the taxes and governance in place before even more people question their scares. Time is short hence the ratcheting up of the panic stories.

  8. Anthony, I don’t see the logic is faulty. An event caused by changing wind patterns 15,000 years ago could be repeated in the near future as wind patterns change as climate changes. No real logic failure there.

  9. A new scare story a day; one imagines they are so short of new ideas that they have to sit in a room and think up something silly.

  10. I remember back in the ’80s when South America was positively doomed because of the “ozone hole” that we were supposedly causing. Turned out that was just natural variation, too.

  11. It took over 1,000 years for Western Europe to recover from the end of the roman warm period and reconstitute a literate society with centralized governance and important trade links. Reversible over the course of history, but irreversible over the course of memory.

    When warmists talk about irreversible effects, it really means irreversible over a time span shorter than several centuries.

  12. So they seem to be saying that something that last happen in the middle of the last ice age.
    ls now further proof of global warming.

    Yes that makes total sense.

  13. To answer the question “what makes them think that it happening again now is due to global warming?” I invoke the old proverb ‘When the only tool you have is a hammer, everything begins to look like a nail.’

  14. This migration of westerly winds towards the south pole has been observed again in modern times and is expected to continue under a warming climate,”

    No worries then, no more warming – no poleward migration.

  15. I don’t believe I’ve ever seen so many non sequiturs in a paper. It’s the Plan 9 from Outer Space of science papers …

    Pointman

  16. To be fair, they don’t claim, in the piece above anyway, that the warming they are talking about is in any way man-made.

  17. Why would you take a time period that was squarely in the last ice age with temps well below today’s as a comparison of what we see today? During the last ice age, indeed, the air was cooler and drier with or without westerlies, whether migrating or not.

    When this epidemic is over with, we have a big clean up to do. We will have to asterisk the PhD’s of the last two decades, quarantine them for remedial courses and examinations. We will have to retrain the 90% redundancy of climate scientists into other fields for which they would be obliged to take courses and proficiency examinations, notably in statistics. Many would likely prove unsuitable for acceptance into the new academic sphere. We will have to mark journals of this period with some form of color coding in libraries for review for retraction of 75%+ of the articles as being unscientific. This will all be a costly but worthwhile exercise because it will help to ensure that this “Laputa” bunch is disenfranchised forever.

    “Gulliver sets sail again and, after an attack by pirates, ends up in Laputa, where a floating island inhabited by theoreticians and academics oppresses the land below, called Balnibarbi. The scientific research undertaken in Laputa and in Balnibarbi seems totally inane and impractical, and its residents too appear wholly out of touch with reality.”

    http://www.sparknotes.com/lit/gulliver/summary.html

  18. It’s like the Heartbreak of Psoriasis – EVERYTHING is caused by Global Warming!!!

    re; Pointman’s notice of the Non-Sequitur’s in this paper – remember, this is post-modern science. It’s not illogical if you RILLY, RILLY, RILLY BELIEVE! that it is the truth. Whatever “truth” means anymore.

  19. Gary Pearse says:
    July 30, 2013 at 10:02 am

    Apropos allusion for Los Putos Mann, et al.

    Also for the allusion to Swift’s Laputa, the B-52 target in the movie “Dr. Strangelove”.

  20. Irreversible… just as it never reversed since 15,000 years ago, so these ice fields never existed.

  21. Isn’t that about the time that people arrived in the Western Hemisphere – so it is our fault after all.

  22. Caleb
    l think l may know the reason behind this.
    Since l have been taking a interest in the global jet stream since 2011. l have noticed that the southern jet stream quite often takes a dive to the south just before it reaches South America. With the jet stream behaving this way would explain why the westerly winds have moved to the south. This is also linked to the warming of Antarctica to the south of South America. As this jet pattern sends warm air down to this part of Antarctica. The fact that this part of Antarctica has been warming. Suggests that this southward movement of the jet in this area has been on the increase in recent years..

  23. When I see papers like this I wonder what else could cause drought in Patagonia? I go off to look. But first here are many examples of low co2 induced mega droughts around the world during our benign Holocene.

    Extreme and persistent drought in California and Patagonia during mediaeval time
    STUDIES from sites around the world1–5 have provided evidence for anomalous climate conditions persisting for several hundred years before about AD 1300. Early workers emphasized the temperature increase that marked this period in the British Isles, coining the terms ‘Mediaeval Warm Epoch’ and ‘Little Climatic Optimum’, but many sites seem to have experienced equally important hydrological changes. Here I present a study of relict tree stumps rooted in present-day lakes, marshes and streams, which suggests that California’s Sierra Nevada experienced extremely severe drought conditions for more than two centuries before ad ~ 1112 and for more than 140 years before ad ~ 1350. During these periods, runoff from the Sierra was significantly lower than during any of the persistent droughts that have occurred in the region over the past 140 years. I also present similar evidence from Patagonia of drought conditions coinciding with at least the first of these dry periods in California. I suggest that the droughts may have been caused by reorientation of the mid-latitude storm tracks, owing to a general contraction of the circumpolar vortices and/or a change in the position of the vortex waves. If this reorientation was caused by mediaeval warming, future natural or anthropogenically induced warming may cause a recurrence of the extreme drought conditions.

  24. “This revealed the decline in the ice-sheet between 15,000 to 19,000 years ago.”

    The coldest part of the last glacial period was roughly between 15.000 and 25,000 years ago(the last glacial maximum)

    Given that this could have happened 19.000 years ago??????

  25. They are clueless that 15,000 years ago the planet started moving out of a glaciation period and warming up into an Interglacial? It would appear that they do not have much knowledge of the Holocene.

  26. Margaret Hardman says:
    July 30, 2013 at 9:40 am

    Anthony, I don’t see the logic is faulty. An event caused by changing wind patterns 15,000 years ago could be repeated in the near future as wind patterns change as climate changes. No real logic failure there.

    Maybe you should try reading a bit more closely:

    “This migration of westerly winds towards the south pole has been observed again in modern times and is expected to continue under a warming climate, likely leading to further ice declines in this area affecting seasonal water storage.”

    Note that “the warming climate” is simply assumed. It plays very neatly into the whole alarmist tone of the paper. If the paper was simply about a repeat of the event 15,000 years ago, why mention the “warming climate”? Logic fail.
    Reading is fundamental.

  27. Meanwhile, in the real world, South America has been getting more rain, and snow up to the tropics…

    iceagenow.info

  28. I haven’t bothered reading the original yet. But the excerpts surely make no sense at all. There is no such thing as a North Patagonia (let alone Central Patagonia) ice-field. Both ice-fields are located in the south of Patagonia. And their importance for the water supply of Chile or Argentina is absolutely negligible. On the Chilean side they discharge mainly to the ocean and in Argentina only a tiny percentage of the country and even tinier of its population depend on those ice-fields for their water supply. Some of their outlet glaciers are actually advancing and Punta Arenas, the southernmost town with a 100+ years temperature record has not experienced any warming in the last century.

  29. Margaret Hardman says at July 30, 2013 at 9:40 am

    Anthony, I don’t see the logic is faulty. An event caused by changing wind patterns 15,000 years ago could be repeated in the near future as wind patterns change as climate changes. No real logic failure there.

    Yes, so far so good.
    But 15,000 years ago the climate changes were certainly not caused by man. The Hyperboreans, Atlantens and Lemurians lacked fossil fuel power stations. They probably lacked existence even.
    It wasn’t catastrophic Anthropogenic Global Warming (cAGW).

    So the logical fail is suggesting that this is either:
    1) Evidence of what cAGW will do.
    or
    2) That a repeat event will be evidence for cAGW (or even AGW for that matter).

  30. The alarmists probably would have tried to blame the 15,000 year old event on modern AGW, if they could think of a way to do it.

  31. “what makes them think that it happening again now is due to global warming?”

    I assume that is a rhetorical question.

  32. John Tillman, Gary Pearse–

    Kong:

    Primary target, the ICBM complex at Laputa. Target reference Yankee Golf Tango Three Six Zero. Thirty megaton nuclear device fused for airburst at ten thousand feet. Twenty megaton nuclear device will be used if first malfunctions. Otherwise proceed to secondary target, missile complex seven miles east of Barshaw. Target reference November Bravo X-Ray One Zero Eight. Fused airburst at ten, check, twelve thousand feet.

  33. Pat Michaels,

    I always wondered why the airburst altimeter was dialed down to zero altitude.

    Also, I don’t think we had a 30 MT nuke in our arsenal.

  34. I read an event 15,000 years ago is today blamed on Global Warming – it may seem very subtle but this paper seems to suggest some other forces at work other than Global Warming if it happened 15,000 years ago. That is the big picture I took from this article.

  35. Interesting, Perito Moreno, the largest of the glaciers in the ice field is actually growing. Water levels in Argentino and Viedma lake are steady and overall there is a great amount of water between the lakes and the glaciers, more than they will use in thousands of years. And if there is a water crisis, they have one of the world’s largest aquifers nearby in eastern Patagonia. This is just another study that observes a current trend then extrapolates that trend into the future indefinitely. Didn’t these people learn their lesson in the 90s when they extrapolated the 1975-98 warming trend indefinitely into the future?

  36. Margaret Hardman says:
    July 30, 2013 at 9:40 am

    An event caused by changing wind patterns 15,000 years ago could be repeated in the near future as wind patterns change as climate changes. No real logic failure there.

    The statement below is the logic fail; something that reversed all by itself 15 kya will now be ‘irreversible’.

    … Worryingly, this study suggests the region may well be on a trajectory of irreversible change …

  37. Billy

    Did you spot the conditional tense being used – irreversible is not inevitable according to your quote. Still don’t see any logic fail and I did read it carefully. To busy watching parking meters.

  38. The irreversible change has clearly reversed in recent years. There has been a large increase in sea ice around the tip of the Antarctic Peninsula where Antarctica is most influenced by westerly winds. Clearly it’s getting colder there.

  39. When I read the article, weones came to mind. This article is probably obliquely related to HidroAisen.

  40. “the southern part of the ice-field did not appear to be impacted by the movement of these winds.”

    But was it affected by the movement of these winds?

  41. If the contraction of the ice sheet 15,000 yr ago was irreversible, how can it be happening again? Now? ??????

  42. Margaret Hardman says:
    July 30, 2013 at 2:02 pm

    “Billy

    Did you spot the conditional tense being used – irreversible is not inevitable according to your quote. Still don’t see any logic fail and I did read it carefully. To busy watching parking meters.”

    Margaret, what would the world say if they hadn’t used (a weak) conditional! (Caleb says:
    July 30, 2013 at 10:10 am: “Likely an interesting study, under the bright pink tutu it is necessary to prance about in, to gain grant money.”

    This CAGW-speak we refer to as woulda-coulda-shoulda here. It is designed for mass consumption by folks that don’t make the distinction. What could possibly suggest that it would be irreversible. There isn’t even enough to say it will even happen let alone plot its course to remain so forever. I find it particularly illogical to me because they are comparing this to an ice age scenario with low CO2 in the atmosphere- not a CO2-glutted global warming scenario. If I were to say to you “suggests that the sun won’t come up tomorrow” would that make it alright for you? Science should not be a semantic exercise, although it is clear that the post-normal science of CAGW proponents works this aspect to the bone. If they were presenting to a skeptical scientific community (the usual type before all this NGO science got started – let’s pray this is reversible), they would highlight first off how they determined which way the wind was blowing and where the jet stream was, before they got any further. That’s just it, they don’t have to anymore.

  43. I guess they missed the fact is no longer warming and has been cooling since at least 2005. Of course, reality doesn’t help get a nice grant so let’s just throw in some maybes and pick up a check.

  44. If conditions similar to today ended the last ice age, and caused a warm-up some 15,000 YA comparable to the one we are experiencing today, then what’s to say that that whatever happened at the beginning of the Younger Dryas Stadial 12,900 YA that triggered a sudden return to ice age conditions that lasted another 1,300 years can’t happen again too?

  45. dbstealey says:
    July 30, 2013 at 12:26 pm

    Correct. Mk 41/B41 bomb (1961-76) was our most energetic, at max yield of 25 MT.

    Also right that a zero altitude air burst is better known as a surface burst.

  46. My fiance writes from Valparaiso:

    Aqui hace frio las mañanas sobre todo son muy heladas.

  47. Out of date already.

    The jets in both hemispheres moved poleward up to around 2000 but the trend has reversed since then..

  48. Margaret Hardman says:
    July 30, 2013 at 9:40 am
    Anthony, I don’t see the logic is faulty. An event caused by changing wind patterns 15,000 years ago could be repeated in the near future as wind patterns change as climate changes. No real logic failure there.
    =========================
    Occam tells us that whatever caused the change in the past is the most likely answer today. And that it will be no more irreversible than it was 15,000 years ago. 15,000 years ago it was cavemen in SUV’s that caused the shift. same today.

  49. Margaret Hardman says:
    July 30, 2013 at 9:40 am
    Anthony, I don’t see the logic is faulty. An event caused by changing wind patterns 15,000 years ago could be repeated in the near future as wind patterns change as climate changes. No real logic failure there.

    The CAGW refuses to look at the palaeo climate record as a whole, which shouts loud and clear that the earths climate and biosphere have been in rude health for most of the Phanaerozoic (last 535 million year period after Cambrian explosion and existence of multicellular life) with CO2 levels higher – by up to 20x – than the present. That the idea of dangerous runaway warming with CO2 in the mere hundreds of ppm is impossible and nonsensical.

    But no – instead they find a tiny sliver of palaeo history and play a conjuring trick with it. O look – 15000 years ago climate abruptly warmed, and winds moved south. Now winds are moving south again – ergo climate catastrophe on the way. What if winds move south for other reasons and even in cooling periods? As always a string of hidden assumptions, always fatal in climate research.

    I wonder if this paper mentions the term “ice age” or “glaciation” anywhere. I wonder if the authors even know about ice ages. 15000 years ago the earth abruptly warmed with the glacial-interglacial transition starting the Holocene (a false start due to the Younger Dryas). Such glacial-interglacial transitions have happened on a regular basis for the last 3 million years. Is this news to you? I guess its easy to be sucked by peer pressure to thinking that only human input into the atmosphere can change climate, nothing else.

  50. “…migration of westerly winds towards the south pole happened 15,000 years ago, what makes them think that it happening again now is due to global warming?”

    Um, just a wild guess; Funding.

  51. The study can be accessed here.

    http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3698495/

    Before I went hunting it up, I wondered what could trigger a shift of wind patterns. I’ve been reading about changes in the NH jet stream due to the decreasing temperature grtadient between the tropics and the Arctic and wondered if a similar effect might be occuring in the SH. The cause of the shift in SH westerlies is not discussed in the paper, but the analog that people have queried is there. Climate was warming then.

    “Our constraints on the LGM and lateglacial deglaciation record shows the PIS response to climate forcing through this important climate transition, with initial retreat after 29.0 ka and the ice sheet remaining close to its LGM dimension until ~19 ka. Data from Cerro Oportus and Cerro Tamango indicate stepped thinning between 19 ka and 18.1 ka, followed by rapid thinning throughout the altitudinal profile until a brief still stand or advance at around 16.9 ka. Evidence from a series of former ice-dammed lakes within this limit suggests that ice had withdrawn rapidly to within 10–15 km of its present extent by 15.6 ka.”

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