’90% of the last million years, the normal state of the Earth’s climate has been an ice age’

coverage-last-ice-age

From the American Thinker

The Coming Ice Age

By David Deming

Those who ignore the geologic perspective do so at great risk.  In fall of 1985, geologists warned that a Columbian volcano, Nevado del Ruiz, was getting ready to erupt.  But the volcano had been dormant for 150 years.  So government officials and inhabitants of nearby towns did not take the warnings seriously.  On the evening of November 13, Nevado del Ruiz erupted, triggering catastrophic mudslides.  In the town of Armero, 23,000 people were buried alive in a matter of seconds.

For ninety percent of the last million years, the normal state of the Earth’s climate has been an ice age.  Ice ages last about 100,000 years, and are punctuated by short periods of warm climate, or interglacials.  The last ice age started about 114,000 years ago.  It began instantaneously.  For a hundred-thousand years, temperatures fell and sheets of ice a mile thick grew to envelop much of North America, Europe and Asia.  The ice age ended nearly as abruptly as it began.  Between about 12,000 and 10,000 years ago, the temperature in Greenland rose more than 50 °F.

We don’t know what causes ice ages to begin or end.  In 1875, a janitor turned geologist, James Croll, proposed that small variations in Earth’s orbit around the Sun were responsible for climate change.  This idea enjoyed its greatest heyday during the 1970s, when ocean sediment cores appeared to confirm the theory.  But in 1992, Ike Winograd and his colleagues at the US Geological Survey falsified the theory by demonstrating that its predictions were inconsistent with new, high-quality data.

The climate of the ice ages is documented in the ice layers of Greenland and Antarctica.  We have cored these layers, extracted them, and studied them in the laboratory.  Not only were ice ages colder than today, but the climates were considerably more variable.  Compared to the norm of the last million years, our climate is remarkably warm, stable and benign.  During the last ice age in Greenland abrupt climatic swings of 30 °F were common.  Since the ice age ended, variations of 3 °F are uncommon.

For thousands of years, people have learned from experience that cold temperatures are detrimental for human welfare and warm temperatures are beneficial.  From about 1300 to 1800 AD, the climate cooled slightly during a period known as the Little Ice Age.  In Greenland, the temperature fell by about 4 °F.  Although trivial, compared to an ice age cooling of 50 °F, this was nevertheless sufficient to wipe out the Viking colony there.

In northern Europe, the Little Ice Age kicked off with the Great Famine of 1315.  Crops failed due to cold temperatures and incessant rain.  Desperate and starving, parents ate their children, and people dug up corpses from graves for food.  In jails, inmates instantly set upon new prisoners and ate them alive.

The Great Famine was followed by the Black Death, the greatest disaster ever to hit the human race.  One-third of the human race died; terror and anarchy prevailed. Human civilization as we know it is only possible in a warm interglacial climate.  Short of a catastrophic asteroid impact, the greatest threat to the human race is the onset of another ice age.

The oscillation between ice ages and interglacial periods is the dominant feature of Earth’s climate for the last million years.  But the computer models that predict significant global warming from carbon dioxide cannot reproduce these temperature changes.  This failure to reproduce the most significant aspect of terrestrial climate reveals an incomplete understanding of the climate system, if not a nearly complete ignorance.

Global warming predictions by meteorologists are based on speculative, untested, and poorly constrained computer models.  But our knowledge of ice ages is based on a wide variety of reliable data, including cores from the Greenland and Antarctic ice sheets.  In this case, it would be perspicacious to listen to the geologists, not the meteorologists.  By reducing our production of carbon dioxide, we risk hastening the advent of the next ice age.  Even more foolhardy and dangerous is the Obama administration’s announcement that they may try to cool the planet through geoengineering.  Such a move in the middle of a cooling trend could provoke the irreversible onset of an ice age.  It is not hyperbole to state that such a climatic change would mean the end of human civilization as we know it.

Earth’s climate is controlled by the Sun.  In comparison, every other factor is trivial.  The coldest part of the Little Ice Age during the latter half of the seventeenth century was marked by the nearly complete absence of sunspots.  And the Sun now appears to be entering a new period of quiescence.  August of 2008 was the first month since the year 1913 that no sunspots were observed.  As I write, the sun remains quiet.  We are in a cooling trend.  The areal extent of global sea ice is above the twenty-year mean.

We have heard much of the dangers of global warming due to carbon dioxide.  But the potential danger of any potential anthropogenic warming is trivial compared to the risk of entering a new ice age.  Public policy decisions should be based on a realistic appraisal that takes both climate scenarios into consideration.

(h/t to Ron de Haan)

David Deming is a geophysicist and associate professor of Arts and Sciences at the University of Oklahoma.
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129 Responses to ’90% of the last million years, the normal state of the Earth’s climate has been an ice age’

  1. John Galt says:

    Well said!

  2. ward says:

    This para has a rather Gorian quality to it. Does not seem credible.

    “In northern Europe, the Little Ice Age kicked off with the Great Famine of 1315. Crops failed due to cold temperatures and incessant rain. Desperate and starving, parents ate their children, and people dug up corpses from graves for food. In jails, inmates instantly set upon new prisoners and ate them alive.”

  3. Jack Green says:

    We’re overdue and any explanation as to how these “ages” can end so abruptly?

  4. Peter says:

    Sobering post, thanks. Reminds me of a lecture I recently sat through explaining how the world will end, as the sun ages and grows into a red giant the temperature on earth will approach a thousand degrees thereby obliterating all life. At least the stuff we know of anyway. Seems that if isn’t one thing it’s another.

  5. Dave Middleton says:

    Any freshman geology student would have learned enough in Earth Science 201 Physical Geology to understand this subject.

    Throughout the vast majority of geologic time, year-round ice in the polar regions was the exception, rather than the norm. About every 130 million years the Earth experiences an “Ice Age”…We’re living in an “Ice Age” right now. This “Ice Age” began about 30 million years ago. Over the last 3 million years, the “Ice Age” has gotten colder. As Dr. Demming points out, the Pleistocene has been dominated by ~130,000-year episodes of continental glaciation with brief interglacial periods occurring between the glacials.

    We’re fortunate to be living in a particularly warm part of an interglacial. If the ice core CO2 data are correct (they aren’t) and CO2 drives climate (it doesn’t)…It should be a lot warmer now than it was during the last interglacial. But it was actually considerably warmer during the Sangamon interglacial (~130,000 years ago) than it is now…

    I “borrowed” this chart from IPCC TAR and “annotated” it…

    http://i90.photobucket.com/albums/k247/dhm1353/IPCCchart.jpg

  6. tarpon says:

    It doesn’t take much research to figure this out. It’s just that most people haven’t bothered.

    But the real question is why the earth entered into this cyclic ice age pattern some 5 million years ago — And why the ice ages come, and go. I bet there is a cycle there worth studying, if mankind can figure out what it is. My guess is CO2 doesn’t have anything to do with it.

  7. P Walker says:

    I’ve often wondered why more geologists haven’t weighed in on AGW . Perhaps the true believers have been afraid to ask them . By the way , Ian Plimer’s new book is out of print and unavailable – according to Amazon .

  8. Jim Papsdorf says:

    Ward:
    RE:

    “This para has a rather Gorian quality to it. Does not seem credible.

    “In northern Europe, the Little Ice Age kicked off with the Great Famine of 1315. Crops failed due to cold temperatures and incessant rain. Desperate and starving, parents ate their children, and people dug up corpses from graves for food. In jails, inmates instantly set upon new prisoners and ate them alive.”

    Starvation will do strange things to people:

    “Uraguayan Air Force Flight 571, also known less formally as the Andes flight disaster, was an airline flight carrying 45 people that crashed in the Andes on October 13, 1972. The event was concluded by December 23, 1972, when the last of 16 survivors were rescued. More than a quarter of the passengers died in the crash and several survivors of the initial impact had died of cold and injuries by the next day.

    The remaining survivors had very little food and no way to make heat in the harsh climate, over 10,000 feet altitude. Faced with starvation the survivors eventually fed on the dead passengers who were preserved in the snow. Rescue teams were not aware of the survivors until 72 days after the crash when Nando Parrado and Roberto Canessa, after a 12 day trek across the treacherous Andes mountains, found a Chilean huaso who guided them to safety where help was found for the other survivors still trapped at the crash site.

    http://en.wikipedia.org/wiki/Uruguayan_Air_Force_Flight_571

  9. Leon Brozyna says:

    Well, whatever we do, don’t send Mr. Gore on any extended speaking tours in Canada or Northern Europe — it’ll take us 100,000 years to recover.

  10. Jon H. says:

    It is not possible for an ice age to begin or end abruptly, Al Gore, the most notable scientist in climatology the world has ever seen says tempreture changes happen slowly over a millennium or more. It’s practically Newtonian.

    After all Al Gore has a Bachelor Degree in Art. Who can argue with someone as well educated?

    Sarcasm for the WIN! :)

  11. Austin says:

    In Europe there was already social turbulence prior to 1315. Many institutions were seized by the states at that time – most famously in 1307 and 1312 the Templar’s estates were seized in many nations – they were one of the largest food producers at the time. So, the 1315 famine was certainly triggered by bad weather – but there is a political and social subtext as well – nations were not as robust as they used to be due to internal chaos brought about by poor decision making.

  12. Carlos says:

    My guess is CO2 doesn’t have anything to do with it.

    Don’t be too sure. The geologic history of the earth contains within it the record of progressive CO2 depletion (Coal, Oil, Limestone). The interglacial periods have also gotten shorter. Could there be a connection? Couldn’t this CO2 depletion have cooled the earth?

    One could also argue: Shouldn’t we try to put the missing CO2 back where it belongs whenever/however possible?

  13. JP says:

    Ward,
    I don’t know about the prevalence of widespread canabalism, but the 1315-1318 Famine is well documented. It all began by a series of intense, largescale cyclones that swept into Northwest Europe. These areas of low pressure, came in from the North Atlantic bringing incessent rains and winds. About 1 storm every 72-96 hours arrived for months on end. From Pentacost through August, farmers watched thier crops wash away or drown under sheets of water. From what I read, entire regions from Brittany-Normandy through the Benelux and Westphalia and Saxony were in knee deep mud. The entire summer wheat harvest and wine crops were ruined. Farmers had to consume thier seed stock just to survive; of course, with thier seedstock gone, they had nothing to plant in 1316. Starvation soon followed.

    No one really knows exactly what occured synoptically, but some forensic meterologists surmised cooling waters over the North Atlantic increased the atmospheric temperature gradient, which lead to the disasterous spawning of European storms. The 14ht Century saw wild gyrations in the NAO, as the climate became highly variable (floods one year, drought the next). One thing was for certain, the nearly 500 years of generally hot, benign climate came to an abrupt end in the 14th Century. The Maunder Minimum was still 300 years in the future, and when it arrived only made a bad situation worse.

    One thing we have in our favor is a highly scientific agricultural segment. The farmers of the 14th century were subsidence farmers, and grew mainly grains. We are forunate that we have hybird seeds that are more drought resistent than what farmers had even 30 years ago. Of course, a late spring frost covering large areas of the Plains would be disasterous. This spring, the farmers are 2-3 weeks behind in planting thier corn. Farmers in my neck of the woods barely have 100 acres planted (out of 10,000 to 15,000 acres total per farm) due to the cold rains. Good thing we live in 2009, and not 1609.

  14. Ron de Haan says:

    According to this publication, the Russian government is preparing for the next ice age: http://www.iceagenow.com/A_Cold_War_That_Russia_Can_Win.htm

  15. Smokey says:

    Carlos,

    Your speculation has no basis in fact, because CO2 levels follow temperatures, not vice-versa: click

  16. anna v says:

    I thought that the Milankovitch Theory explained fairly well the ice ages? Seems to be missing above.

  17. Alan the Brit says:

    Fantastic piece of common sense & logic. I hadn’t heard of the canabalism before but don’t doubt its accuracy. As someone’s already said starvation does strange things to peoples minds. Looking at the map, the south-west of England could get jolly crowded in the future. Is there a possibility that, if we head for a Little Ice Age due to the quiet Sun, the UN/IPCC could be sued in an international court for negligence & incompetence for failing to take into account a possible cooling of the climate?

    Jon H;-)

    If Al Gore has an art degree, was it he who coloured in the graphs with pretty colours? If he took a maths degree, he could become one of the world’s greatest computer painters! Anyway there won’t be an ice age for a while with all that hot air circulating at the UN, the IPCC, the EU, & in Tennesse!

    BTW it’s very cold in the UK right now, when will this sizzling summer start? We have had the log-burner re-lit several times throughout April & also this May four times.

  18. ward says:

    JP: That was what I was questioning. I am aware of what happened then in terms of climatoligical changes, but had never heard of people eating thier children or digging up graves to eat rotted corpses.

    You add some good additional color to the climate side. Thanks.

  19. rbateman says:

    Ron de Haan (08:56:11) :

    Yes, in fact, Putin & Gasprom are banking on it.
    The fact that the known universe is expanding and the Sun is ageing may have a cycle that keeps the Earth moving along an ever increasing occurence and depth of Ice Ages.

  20. Rhys Jaggar says:

    When people say human life is not consistent with an ice age, don’t they mean ‘human life in high latitudes’?

    I can’t believe that you couldn’t live in Tanzania during an ice age. Mightn’t be as hot, but it’d sure be well above freezing. Ditto India. Ditto Australia. Ditto Brazil.

    I think we’re equating human life with where a lot of us come from.

    Spain might be quite a temperate climate in an Ice Age. How about Egypt? Or Mexico?

  21. Dave Middleton says:

    Replying to…

    P Walker (08:28:47) :

    I’ve often wondered why more geologists haven’t weighed in on AGW . Perhaps the true believers have been afraid to ask them . By the way , Ian Plimer’s new book is out of print and unavailable – according to Amazon .

    Most geoscientists have real jobs…;)

    On Plimer’s book, Amazon says “Out of Print–Limited Availability.”

    Maybe that just means they don’t carry it and have to access it from a secondary market. I’ve been meaning to buy a copy of it.

    There is a really goo AAPG book, Geological Perspectives of Global Climate Change edited by Lee Gerhard, that provides a very good geological perspective.

  22. Glug says:

    Regarding the comments on Winograd’s work, this is certainly revisionist and just slightly out of date in terms of when this debate was finished, put to bed and concluded.

    The 1992 work of Winograd certainly did present some inconsistencies between different paleoclimate records, yet it’s acceptance is overstated by the author above. An editorial in Science accompaned the publication setting it in context:

    http://www.sciencemag.org/cgi/reprint/258/5080/220.pdf

    It’s clear that something else was needed to settle the debate either way i.e. the coral records. The coral records have come down firmly on the side of the existing theory and the interpretation of the vast body of marine sediment core data:

    Author(s): Thompson WG (Thompson, William G.), Goldstein SL (Goldstein, Steven L.)
    Source: QUATERNARY SCIENCE REVIEWS Volume: 25 Issue: 23-24 Pages: 3207-3215 Published: DEC 2006

    And better relation to rate of ice cap loss/accumulation support Milankovitch:

    http://www.agu.org/pubs/crossref/2006/2006GL027817.shtml

    And from just down the road from Devil’s Hole in CA:

    http://dx.doi.org/10.1016/j.chemgeo.2004.11.005

    Author(s): Yang WB, Lowenstein TK, Krouse HR, Spencer RJ, Ku TL
    Source: CHEMICAL GEOLOGY Volume: 216 Issue: 1-2 Pages: 99-111 Published: MAR 15 2005

    Milankovitch theory remains intact.

  23. Dave Middleton says:

    Replying to…

    Carlos (08:49:19) :

    My guess is CO2 doesn’t have anything to do with it.

    Don’t be too sure. The geologic history of the earth contains within it the record of progressive CO2 depletion (Coal, Oil, Limestone). The interglacial periods have also gotten shorter. Could there be a connection? Couldn’t this CO2 depletion have cooled the earth?

    One could also argue: Shouldn’t we try to put the missing CO2 back where it belongs whenever/however possible?

    If there was a connection, there ought to be a long-term correlation between CO2 and temperature. However, there is no such correlation…

    http://i90.photobucket.com/albums/k247/dhm1353/CO_vs_Temp.jpg

  24. John Galt says:

    By the way , Ian Plimer’s new book is out of print and unavailable – according to Amazon .

    I really want to get a copy of Plimer’s book. What’s the story here? Too much demand? Not available in the USA?

  25. Bruce Cobb says:

    Carlos (08:49:19) :
    One could also argue: Shouldn’t we try to put the missing CO2 back where it belongs whenever/however possible?
    True, one could, if one were an AGW/CC Believer, but once one begins to actually look into the science, one will tend to lose the Faith and embrace science instead.
    “Putting the C02 back”, as in geoengineering would be nothing but a fools’ errand, with possibly harmful environmental consequences, in addition to being both useless and expensive.

  26. Yukon Peat says:

    Jack Green wrote: “We’re overdue and any explanation as to how these “ages” can end so abruptly?”

    Abruptly in Geologic terms can be in the range of a thousand years or more. Here is one resource that addresses what did (or didn’t ) cause the end of the last ice age.
    http://www.usc.edu/uscnews/stories/14288.html

  27. Gary says:

    “We don’t know what causes ice ages to begin or end. In 1875, a janitor turned geologist, James Croll, proposed that small variations in Earth’s orbit around the Sun were responsible for climate change. This idea enjoyed its greatest heyday during the 1970s, when ocean sediment cores appeared to confirm the theory. But in 1992, Ike Winograd and his colleagues at the US Geological Survey falsified the theory by demonstrating that its predictions were inconsistent with new, high-quality data.”

    Well, not quite. This study by Winograd, et al. on 21 samples in a single vein of calcite provides scant evidence to refute the dozens of deepsea sediment cores that consistently and independently show periodicities in chemical and microfossil abundance timeseries (several species) that match the Milankovich cycles. Orbital parameters are the primary forcing for glacial-interglacial oscillation, but other factors certainly contribute.

  28. crosspatch says:

    Modern Man has probably never experienced the change from interglacial to to glacial conditions; certainly not at high latitudes. Homo Erectus went through a couple and migrated all the way to China but probably had a very hairy body.

    We aren’t a very cold-adapted species. It will be “interesting” when it happens but I wouldn’t want to be around when it does.

  29. GeoS says:

    Regarding Plimer’s book the follwing web site is interesting: http://awesternheart.blogspot.com/2009/05/heavenearth-on-fire.html
    I guess we’ll just have to wait awhile.

  30. John G. Bell says:

    Not knowing what precipitates ice ages is an unsatisfactory situation. Solar variation seems a natural candidate. I start from the proposition that we live in unusually good times. That civilization has been established and continues whereas before no sufficiently long period of favorable climate occurred to foster it. You would expect scientists of our age to be pointing out that the sun is remarkable in its stability. That it could not be the cause of significant climate change.

    This reminds me of the classic Operations Research problem where returning B17s were examined and their battle damage assessed. The critical parts of the aircraft were those that were never found to have failed. We can’t armor parts of the sun to protect ourselves from climate change. We can store grain and otherwise build up surpluses to give our society some chance to adapt.

    It is an interesting time that we live in. If we are fortunate what we learn today may be of great use to some distant generation.

  31. P Walker says:

    Dave ,
    Thanks for the reference – I will try to get a copy . As for Amazon , I tried to get Plimer’s book yesterday , via proxy as I don’t do internet transactions , and was informed that it was unavailable .

  32. GeoS says:

    Re my last, you might also be interested in the following newspaper review in Oz.
    http://www.connorcourt.com/catalog1/index.php?main_page=page&id=14&chapter=0&zenid=0319813286cff4077f7a534603db643b

  33. Jim B in Canda says:

    Anthony,

    You like doing polls, here’s one I would like to see on your site. A debate on the topic would be interesting, as well.

    With mankinds current state of technology, could humanbeings fend off the next big iceage?

  34. Ron de Haan says:

    rbateman (09:10:21) :

    Ron de Haan (08:56:11) :

    “Yes, in fact, Putin & Gasprom are banking on it.
    The fact that the known universe is expanding and the Sun is ageing may have a cycle that keeps the Earth moving along an ever increasing occurence and depth of Ice Ages.”

    Yes, but if you take a look at the ice age map there won’t be any Russia.
    They always will be an unreliable supplier.

  35. crosspatch says:

    OT: As of today, the temperature at the North Pole is above the melting point of sea ice (got up to -0.6C over the past day).

  36. tty says:

    Rhys Jaggar (09:16:30) :

    Sure, tropical and subtropical areas remain inhabitable during glaciation, but the climate becomes somewhat cooler and much drier. Most of Africa turns into desert or dry steppe during glaciation and so does much of the Caribbean and South America, including large parts of the Amazon basin, so there is really no doubt that a glacial Earth could only support a fraction of the present human population, despite the fact that vast areas of continental shelf is exposed by the low sea-level.
    By the way the map at the top is of the second-to-last glaciation about 200,000 years ago. Ice in Russia and Siberia covered much smaller areas during the last glaciation.

  37. E.M.Smith says:

    ward (08:05:54) : This para has a rather Gorian quality to it. Does not seem credible.

    On their way out west, a party of normal relatively modern U.S. citizens got stuck in the snow at what is now Donner Pass. It created quite a stir when they were rescued and discovered to have survived by eating each other…

    http://www.donnerpartydiary.com/

    The survivors went on to California and some became relatively famous and prosperous. (There is even a school named for one of them, Reed School in San Jose, since they became a prominent family in that area…)

    Cold, snow, and lack of food, starvation? It always comes with stories of eating anything that’s dead (and sometimes those that are not dead yet…)

    We have several hundred million years of evolution behind us to be an omnivore that SURVIVES. We have a couple of thousand years of civilization and only a few hundred years that really demonized behaviours like murder, rape, and cannibalism. (Look at what the Roman Empire leaders did… and need I mention Idi Amin?) We aren’t that long “out of the bush”, and when stressed, it shows…

    BTW, we forget how hard our ancestors had it and how grounded in reality they were. No contraception. Variable crops. Solution: At the end of the harvest season the parents would count up the food stocks. They would figure out just exactly how many people could survive the winter on that food. If that meant they were one kid over the survival line, one kid was led to the forest and left to die (or worse). I’m sure they didn’t like doing it, but they also knew that if they did not do it: 2 or 4 would die of starvation after the food ran out before the next harvest was ripe.

    I’m not going to provide links to the documented history of the practice. I find it too disturbing personally. But don’t ever think we are not capable of it. I’m certain that if put in the same circumstances I could decide who was essential to keep alive and who was, literally, lunch. Some languages even have a specific word for the practice of thinning out the offspring at the start of winter… that only happens after a practice has been around for a very long time.

    Minor point: The British used to bowl with the skulls of Danes. Think about it… We are much more squeamish than folks of old.

  38. E.M.Smith says:

    Jack Green (08:14:32) : any explanation as to how these “ages” can end so abruptly?

    There are some interesting ideas. One has to do with rock falls from space. These have a distribution that is well known with Really Big Ones being less common that medium and much less common than small. So we had what looks like a large rock fall into the North American ice sheet at the end of the last glacial. It has a tendency to cause an abrupt change when a few thousand megatons of TNT worth of energy gets deposited into the ice sheet in a few seconds…

    Another has to do with the methane clathrate on the ocean bottom. It’s only stable under pressure and is prone to explosive decomposition. So as the ice piles up on the continents the oceans drop. At some point the clathrate destabilizes (which lowers the weight of water over it by filling it with bubbles leading to more destabilization). The notion is that a hugh bolus of methane gets released into the air at the point where the ocean drops too low. This methane then causes a warming spike. Basically, it’s an ocean level / clathrate oscillator with 100,000 year periodicities.

    Then there is the plant oscillator theory. Ice age buries plants under ice. Cold slows photosynthesis and ocean formation of carbonates. Eventually the natural volcanism leads to added CO2 leading to warming. As glaciers retreat, buried plants release CO2 from decay. Eventually plants start to flourish again. Eventually the planet is warm and the plants have a Great Spike of growth – sucking the CO2 down to the point where they suffer a crash from CO2 deficiency and the snow begins. Basically the theory is a CO2 / ice oscillator based on a plant timer circuit.

    These things are all plausible. Which has veracity? I donno… The reality is likey to be a mix of small bits of each along with things we just don’t understand. FWIW, one of the sites I like most on the ice age issue is:

    http://www.sciencebits.com/ice-ages

    That makes a connection to the galactic arms and cosmic rays…

    At least someone has a clue. From:

    http://www.eworldvu.com/international/2009/2/4/a-cold-war-that-russia-can-win.html

    The Russian report summarized its findings as follows: “The evidence from core samples suggests that the 12,000 years of warmth we call the Holocene period is over. Apparently, we’re headed into an ice age of about 100,000 years, give or take. As for CO2 levels, core samples show conclusively they follow the earth’s temperature rise, not lead it.

  39. Ron de Haan says:

    Austin (08:46:13) :

    “In Europe there was already social turbulence prior to 1315. Many institutions were seized by the states at that time – most famously in 1307 and 1312 the Templar’s estates were seized in many nations – they were one of the largest food producers at the time. So, the 1315 famine was certainly triggered by bad weather – but there is a political and social subtext as well – nations were not as robust as they used to be due to internal chaos brought about by poor decision making”.

    The cold started much earlier according to this time line:

    Medieval glaciation, prior to the LIA:

    * late 1100s: Sharp fall in Camp Century ice-core 18O content signals lower temperature in North Atlantic region.

    * 1200: Foraminifera in deep Atlantic sediments show culmination of warming trend of preceding few centuries.

    * 1200: Beginning of increased sea ice in coastal waters of Iceland.

    * 1200s: Glaciers began to advance in Iceland.

    * 1215-1350: Glaciers began to advance in several parts of Europe.

    * 1215: Oberriederin (irrigation canal) overrun by advance of Aletsch glacier; radiocarbon dates on buried larch; canal head still covered by modern Aletsch glacier.

    * 1227: Thick sea ice on the Baltic allowed a German army to march from the mainland of Estonia to the islands of Muhu and Saaremaa and to capture those islands (Tannberg et al. 2000).

    * 1261: Greenland accepted sovereignty of the King of Norway; Iceland also voted allegiance to the king in 1262.

    * 1275-1300: prolonged drought caused disappearance of cliff-dwelling Anasazi culture in southwestern U.S. (Peterson and Haug 2005).

    * 1280: Radiocarbon date on wood (Pinus cembro) of forest buried by advance of Grindelwald glacier; forest does not again grow on site today.

    * 1300s: Decline of vineyards in Germany; vineyards completely disappeared in England.

    * 1300-1350: Fishing replaced cereal crops as main food resource in Iceland.

    * 1315: Crop failure and starvation in northern Estonia (Tannberg et al. 2000).

    * mid-1300s: Old sea route from Iceland directly west to Greenland impassable due to southward expansion of sea ice; serious decline began in Greenland settlements.

    * 1340-50: Western (northern) settlement in Greenland abandoned and derelict.

    * 1350: Beginning of disasterous wind-blown sand drifting along northwestern coast of Denmark. Episodes of wind erosion and sand-dune migration occurred several times during the following centuries (Clemmensen and Andersen 1998).

    * 1380-1460: Minimal sea-ice cover around Iceland.

    * 1397: Union of Kalmar; Greenland and Iceland became colonies of Danish Kingdom.

    * 1400-1700: 3‰ decline in 18O values for Inuit and Norse teeth in western Greenland implies significant climatic cooling–see Fig. 19-16.

    Norse skeletal remains from graves at Hvalsey church, Greenland. 18O values from tooth enamel indicate sharply colder temperature during the Little Ice Age (Fricke et al. 1995). Photo by Preben Jensen; reproduced by permission.

    * 1408-10: Last reliable account of Norsemen still living in Greenland; all had perished by end of 15th century.

    * 1460: Increased sea ice in coastal waters of Iceland.

    * 1460-1560: End of Medieval glaciation was followed by a century of relatively mild climate.

    * 1510: German merchants visited Greenland and found Inuits living among ruins of Norse settlements.

    * 1530-75: Chamonix/Mont Blanc glaciers (France) advanced, but caused no damages.

    Beginning of Little Ice Age

    For further data: http://academic.emporia.edu/aberjame/ice/lec19/holocene.htm

  40. Andrew Crawford says:

    To be pedantic, the Earth has been in an ice age for 100% of the last million years – and for twice that long – and is still in an ice age right now. Ice ages are defined by the presence or absence of ice at the poles, which is, on a geological timescale, an unusual state for planet Earth. The “normal” climate is several degrees warmer than today and has no polar ice.

  41. David S says:

    The Milankovich cycles should be predictable. So does anyone know where we are now in those cycles and where we will be in the future?

  42. M White says:

    The Famine and Freak weather of the little ice age will be just seen as proof of “Climate Change” by those who believe

    It’s over now, a word from Pen Hadow

    http://www.catlinarcticsurvey.com/audiowebcast.aspx

    http://news.bbc.co.uk/1/hi/sci/tech/7897392.stm

  43. anna v says:

    Well, if we start seeing an ice age coming, we should concentrate our efforts in geoengineering to mitigate it.

    Once I had suggested aluminizing the moon :) thinking it could become a second sun in the sky.

    Certainly mirrors circling could replace the decrease of TSI if that is the reason of the ice ages.

    The only true climate prophecy is that an ice age will come, sooner or later. Brainpower and resources should be concentrating on how to survive.

  44. Noelene says:

    Has anybody seen the diagrams of the multi-storey buildings for growing crops?I don’t know how practical the idea is,but it seems possible.I don’t think people would starve in rich countries,but 3rd world countries would be in for a bad time,especially if the rich countries are busy providing for their people,leaving no time for 3rd world countries.

  45. Dave Middleton says:

    On Winograd…

    In line with some prior posts…As far as I know, the correlation between Pleistocene glaciations and permutations of the Milankovitch Cycles is very strong. However, Winograd does bring up some valid challenges…

    http://water.usgs.gov/nrp/devils.html

  46. Chris Kaiser says:

    Milankovich theory doesn’t explain the 100k year dominant vs 43k year dominant cycles over the last few million years.

    Svensmark 2007 @ http://www.scribd.com/doc/338170/svensmark-2007cosmoclimatology does some interesting work relating our solar system’s travel through the galactic spiral arms as a modulator of cosmic rays to the big picture of ice age periods. Work in progress though.

  47. E.M.Smith says:

    Austin (08:46:13) : In Europe there was already social turbulence prior to 1315. [...] nations were not as robust as they used to be due to internal chaos brought about by poor decision making.

    And you think maybe a slight decay during onset might not have led to some of these instabilities? A “sudden and abrupt” geologic change can easily spread over 100 years. I would fully expect that the years just ahead of the Really Aw Shoot times would be somewhat unstable…

    BTW, one could make comments about the present decisions coming from our government being “not as robust” and “poor decision making”. In fact, I’d even assert that the Very Good Times lead to sloppy decision making since it doesn’t matter as much and you can indulge your fantasies a bit. Then Reality Bites… As they say in the stock trading biz “When the tide goes out you get to see who’s overexposed…” (meaning over leveraged to financial risk – i.e. Lehman and Bear Stearns…)

    Rhys Jaggar (09:16:30) : When people say human life is not consistent with an ice age, don’t they mean ‘human life in high latitudes’?

    Well, since humans were around 20,000 years ago up to their eyeballs in an ice age, I question that assertion… but:

    I can’t believe that you couldn’t live in Tanzania during an ice age. Mightn’t be as hot, but it’d sure be well above freezing. Ditto India. Ditto Australia. Ditto Brazil.

    Very much so. My neighbors have bought land in S. America near the equator and I’ve been invited to join them… Not only will crops be fine there, but there are some places that will improve.

    Spain might be quite a temperate climate in an Ice Age. How about Egypt? Or Mexico?

    Well, the Sahara Pump theory holds that the Sahara oscillates between desert and lush jungle… And in the early Roman history there was much more grain grown in N. Africa. I’d expect the major problems to be related to coping with the change rather than the total growing space.

    I would guess that you lose the polar areas, but the deserts move a bit further south. So look 200 to 400 miles north, that’s what you get (IMHO!).

    tty (10:46:38) : Sure, tropical and subtropical areas remain inhabitable during glaciation, but the climate becomes somewhat cooler and much drier. Most of Africa turns into desert or dry steppe during glaciation and so does much of the Caribbean and South America, including large parts of the Amazon basin,

    That is the historical pattern. But we have some differences now…

    so there is really no doubt that a glacial Earth could only support a fraction of the present human population, despite the fact that vast areas of continental shelf is exposed by the low sea-level.

    Um, I’m willing to doubt the catastrophe is inevitable.

    First off, we eat so much more meat as a planet than at any time in the past, we could all eat much more total food even if we had a 30% cut in total grain production. This is an incredibly important point:

    It takes 10 pounds (or kilos) of grain to raise 1 pound (or kilo) of BEEF. Most of us eat a half pound or so of meat per day (in the modern west, at least). So that’s 5 POUNDS of grain per day. Enough to feed a person for 5 days. That means we could take an 80% cut in the grains grown for beef production and have no reduction in total food we eat if we just eat the cows and then eat the corn and soybeans they would have eaten.

    The great dying will hit cows and pigs; not people in the western world. (Folks already on subsistence grain diets are another issue…)

    Further, if the onset is at all “slow” in human terms (“rapid beyond belief” in geologic terms) we can easily change or agronomy systems to adapt. In a 5 to 10 year period we could convert from corn and soybeans to millet and sorghum (both drought tolerant – and millet can go directly into any corn bread recipe, I have it frequently.) Barley grows where it’s too cold for wheat. You get the idea. We can also build greenhouses and water transport / desalinization if we have 10 to 20 year time spans. It’s all about the rate…

    So while I strongly believe in being prepared, I also strongly believe that we can easily survive another ice age cold epoch without a population catastrophe (whether our political systems will let our technology fix things is another question…)

    http://chiefio.wordpress.com/2009/05/08/there-is-no-shortage-of-stuff/

    Jim B in Canda (10:15:41) :With mankinds current state of technology, could humanbeings fend off the next big iceage?

    An interesting question… I think we could.

    One of the interesting correlations is that ice ages began when the isthmus of Panama closed. The theory is that we could undo ice ages by blasting the channel back open (thus changing world ocean currents) with atomic explosives / excavation.

    While Panama would not like it 8-0 and it does take a lot more looking at to see if it really would function as expected; the needed excavation is not beyond our means…

    IFF the greenhouse gas theory has any truth in it, we could pump out “super greenhouse gasses” pretty easy in massive quantities. Doubt it would work, but easy to test in an ice age catastrophe…

    Then we could also just put several dozen nuclear reactors in key parts of the ice sheet using the ice for cooling. Strategically placed these could significantly slow the ice. It’s amazing what a few terrawatts can do to melt ice…

    I’d be interested in the idea of methane clathrate destabilization (via conventional explosives or stronger stuff ;-) if it could be shown to lead to “greenhouse warming”…

    And finally, it is possible to put up thin mirrors in space and modulate the insolation. It would take 50 to 100 years to get this all built and working, but possible. Personally, I think there are simpler things that could be done with the resources, but it’s an option…

    But frankly, I think it would be a lot easier to just adapt to ice ages. Melt some ice with nukes, pipe it to the edge of the Sahara and grow grains. Move some folks from N. Canada and north slope Alaska down to Montana and Kansas and let them teach the locals how to live. Open my bar on a beach in Brazil ;-) Adaptation CAN be a good thing!

    Also realize that ice ages START fast (in geologic terms) but the ice proceeds to grow more or less linearly (with wobbles) for 100,000 years. So put a marker at the edge of Greenland (the present remaining ice sheet from the last glaciation…) and draw a line to where the ice extent reached in the LAST ice age. (That would be, oh, New York City?). Now measure the distance and divide it by 100,000. That’s the average rate of ice advance per year.

    Last time I did this exercise, it was 800 FEET per year. If you walk 801 feet south each year, you outrun the ice age… (call it 250 meters…)

    And that is probably the most important point to make.

    We all like to think we have a clue about how things change. But we all live in a world far different from geologic realities… You must think Really Large and REALLY REALLY SLOW to grasp the geologic realities.

    The fact is we could easily have already entered the next ice age. It could easily have begun during the LIA, or even a bit before. We will find out in a few thousand more years, maybe… “Abrupt onset” is only abrupt in geologic terms. 1000 years, maybe a few hundred. And that is the “onset”. It still takes 100,000 years to reach the bottom.

    So when you look at those ice extent pictures, realize that’s after that 100,000 years; not at the “onset”. Lets just say I’m not worried about the ice sheet getting even 100 miles closer during my lifetime even if we are already in an ice age that began in the LIA. It might get 1 mile closer… maybe… but that just doesn’t get me worked up much.

    A rock from space is a far far more likely problem and a big volcano is vastly faster onset of the Aw Shoot. They are what we ought to be worried about and preparing for. And a beach bar in Brazil gets me much more excited ;-)

  48. Yukon Peat (09:30:00) :
    Abruptly in Geologic terms can be in the range of a thousand years or more.

    Don’t indulge yourself, think in the siberian mammuts frozen in minutes….found with fresh food in their stomachs.
    Read above Ron de Haan (11:16:53) :

  49. Chris Kaiser says:

    It is interesting to compare this graphic of ’65 million years of climate’:

    http://commons.wikimedia.org/wiki/File:65_Myr_Climate_Change.png

    to Svensmark’s graph on p1.22 of our travel through the Sagittarious-Carina spiral arm.

    http://www.scribd.com/doc/338170/svensmark-2007cosmoclimatology

    Note the abrupt change ~35 million years ago in both.

  50. David L. Hagen says:

    See Nicola Scafetta’s EPA presentation: Climate Change and Its Causes: A Discussion about Some Key Issues Video and Slides, especially slide 66 where he predicts global cooling until 2030-40.

  51. Ron de Haan (11:16:53) : You forgot Pied Piper’s Hamelin, where rats running away from cold in 1284, invaded Hameling. (as invaded towns back then)
    ALMOST NOBODY HAS REALIZED THAT THIS EVENT HAS REPEATED LAST YEAR
    http://www.monstersandcritics.com/news/europe/news/article_1448535.php

  52. Ray says:

    From Pen Hadow: “Without pre-empting any scientific results, my general impression is that the sea ice seems to be thinner than expected. And the fact that it has been predominantly first-year ice means that it’s more likely to totally melt this year.”

    Any comments?

  53. E.M.Smith says:

    Noelene (11:51:54) : Has anybody seen the diagrams of the multi-storey buildings for growing crops?I don’t know how practical the idea is,but it seems possible.

    It is entirely practical. Greenhouse systems are very common today. Odds are that your lettuce and specialty greens in your salad came from a hydroponic greenhouse. (Its easier to deliver clean bug free salad greens of superior quality… for everything but “head lettuce” more or less.) Tomatoes for home use are widely grown in greenhouses. That’s why you get tomatoes 365 days a year in perfect condition… Zukes and cukes too. Even without an ice age, the stability of production and the quality of the product is pushing vegetables in that direction.

    NASA made an interesting mini-greenhouse for space use – even developed special “very short” versions of things like wheat so it could be grown in several “layers” per meter of height.

    As an odd “existence proof”: Grow Houses are now the rage in California Marijuana culture. Hydroponic or potted soil. 100% artificial lighting. The whole structure is entirely insulated from light and heat (to prevent DEA spotting it by the heat signature) if possible. Yet they grow massive crops. All it takes is electricity and a little dirt. (And even the dirt is optional if you go with hydroponics…) Some of these are hugh. Thousands of square feet. They use standard commercial greenhouse lights and materials (which gives you an idea how “ordinary” greenhouse culture is these days…)

    30% of world fish consumption already comes from aquaculture. These can be built in any shape and height (though some are cheaper than others).

    Most of the pigs products you eat came from “pig farms” that are actually more like pig cities. Large ‘grow out’ operations with pig “barns” that are environmentally controlled and computer driven. Same thing for chickens. The only reason they are single story instead of multi story is because land is cheap out there and buildings cost a bit more to build “up”. It is not a technical limit at all.

    see my “no shortage of stuff” link in the above posting and scroll down to the section on food and greenhouses.

    As per the energy needed to run all those grow lights:

    http://chiefio.wordpress.com/2009/03/20/there-is-no-energy-shortage/

    I don’t think people would starve in rich countries,but 3rd world countries would be in for a bad time,especially if the rich countries are busy providing for their people,leaving no time for 3rd world countries.

    And thus has it always been …

    IMHO, that’s the only real problem. How to help our brothers and sisters trapped in bad systems in poor places. They have all the resources they need, it’s just a mater of giving them the understanding and the liberty to use them… tossing money to their corrupt governments is not helpful.

  54. Ray (12:51:08) :
    Just take your bathsuit and go up there!

  55. I would like to know if Vukcevik or another mathematician has made any analysis with Vostok data curves. It would be really interesting.

  56. Leon Brozyna (08:36:17) :
    Well, whatever we do, don’t send Mr. Gore on any extended speaking tours in Canada or Northern Europe — it’ll take us 100,000 years to recover.

    Too late I am afraid! He was in Tromsø (Northern Norway) a couple of weeks ago. Pictured below with the Norwegian foreign minister.
    http://www.vg.no/nyheter/utenriks/klimatrusselen/artikkel.php?artid=542714

    As always, our newspapers constantly repeat that “the ice melting in the Arctic is faster than anticipated”

  57. David L. Hagen says:

    See Easterbrook’s 2001 30 year Global cooling projection

  58. Ray says:

    Adolfo Giurfa (12:54:31) :

    Actually, we planned to go check out the sand dunes in Oregon this summer, but now that you mention it, I think we will change our plans and go see the dunes in the Artic… I heard it will be balmy up there this summer, from the Catlin group.

  59. Gary says:

    “Milankovich theory doesn’t explain the 100k year dominant vs 43k year dominant cycles over the last few million years.”

    Most of the power in spectral analyses of time series that are long enough is found at 100kyr. Remember to consider harmonics and interactions of the 41kyr and 23kyr cycles as well as the effects of all the ice up on the continents having to melt to reduce the albedo when coming out of an ice age and conversely having to be evaporated out of the oceans and precipitated on land when going into an ice age. That’s a lot of “inertia” to overcome and would tend to regularize the beating of the cycles.

    So, while not necessarily “explaining” the dominant periodicity, Milankovich theory certainly supports it.

  60. Richard deSousa says:

    Leon Brozyna (08:36:17) :
    “Well, whatever we do, don’t send Mr. Gore on any extended speaking tours in Canada or Northern Europe — it’ll take us 100,000 years to recover.”

    I like my version better: “… it’ll take us 100,000 years to ‘dig him out’.” LOL

  61. Espen says:

    Newsflash: The Catlin team finds “more evidence of global thaw”: http://www.reuters.com/article/environmentNews/idUSTRE54C6GS20090513

  62. Katlab says:

    Actually one of the things that eventually saved Europe from cycles of starvation was the introduction of the potato from the New World. Prior to that wheat was the main staple. It was subject to bad weather, fires and being trampled during wars. The potato being a root plant could survive all of that. While most Europe, like Germany embraced the potato, the French distained it. Louis XVI ate a potato to try to encourage the populace to start eating them. It failed. The next drought cycle, it was off with their heads.

  63. Jeff Id says:

    I’m surprised you let him get away with blaming meteorologists rather than climatologists for this one. Don’t they get blamed for enough :D

    Fun article.

  64. John Edmondson says:

    Milnkovitch was right:-

    Onset of Ice Ages:-
    Ice Ages are cyclical in the Earth’s recent (last 30m years) past.
    Original cause:-
    Continental Drift of Antartica over the south pole 40m years ago. Ice pack at first formed over mountainous regions. This caused a negative temperature feedback due to the increased albedo, eventually the entire continent was covered with ice. This permanently reduced the surface temperature of the earth.
    Cyclical Ice Ages – Why?
    Once the surface temperature is lowered, the variability of the Earth’s orbit around the sun which causes a variation in the balance of solar radiation NH/SH summer/winter leads to summers cold enough to allow snow to remain unmelted and to accumulate.
    Prior to the Antarctic moving over the South Pole, this would not happen as the earth’s surface would have been too warm.
    The 3 parameters and periodicity is as follows:-
    Orbital eccentricity varies between 0 (a perfect circle, sum always 93m miles away) and 0.1 ( min 88m miles max 98m miles) , period 100,000 years.
    Axial tilt varies between 22.5 and 24.5 degrees , period 41,000 years.
    Precession of the equinox , period 26,000 years. This parameter determines which month the summer solstice occurs, and impacts on the first 2 variables.
    To start an Ice Age, the above parameters cause a lowering of solar radiation in the NH in summer. Snow does not melt from the previous winter and a negetive temperature feedback driven by increased albedo sets in. The Ice marches south. Typically all of Canada, the Northern part of USA all of Scandinavia and most of Northern Europe have permanent Ice sheets. Obviously, Greenland and Antartica remain Ice covered.
    To end an Ice, the opposite to the above. i.e. increased solar radiation at the in NH summer.
    As Ice ages typically last 10 times longer then the inter-glacials, it seems clear that Ice Ages are easier to start then to end.
    If the conditons are right, a run of cold winters caused by something like a Maunder minimum solar event could be enough to tip the climate into an Ice Age. This might be less than 100 years from interglacial to Ice Age, though of course this is hard to prove.
    Current orbital parameters would sustain an Ice Age, all that is needed is a Maunder minimum to push the climate over.
    Something else to ponder, at the moment the Sun has entered a long period of quiet. This is not a Maunder minimum, yet.

  65. Global Madness says:

    At least we know it will be the *warmest* ice age ever ;)

  66. idlex says:

    Does anyone know what global climate was like during the last ice age? Presumably the tropical regions also cooled. But by how much?

  67. Chris Kaiser says:

    “Does anyone know what global climate was like during the last ice age? Presumably the tropical regions also cooled. But by how much?”

    Derek Kelly in an opinion piece from Asia Times Online, wrote a bit about that. It stuck with me. Excerpt:

    “The Earth has also been immensely colder, the CO2 much less plentiful, and the sea levels much lower than today. Fifteen thousand years ago, the sea level was at least 90 meters lower than it is today. The land looked bare because it was too cold for beech and oak trees to grow. There were a few fir trees here and there. No grass grew, however, just shrubs, bushes and moss grass. In the northern parts of North America, Europe and Asia there was still tundra. The animals were different from today too. Back then there were woolly mammoth, woolly rhinos, cave bears (the former three now extinct), bison, wolves, horses, and herds of reindeer like modern-day reindeer.”

    Full article here: http://www.atimes.com/atimes/Front_Page/GB25Aa02.html

  68. Wally says:

    “ohn Edmondson (14:00:45) :
    Milnkovitch was right:-

    Onset of Ice Ages:-
    Ice Ages are cyclical in the Earth’s recent (last 30m years) past.
    Original cause:-
    Continental Drift of Antartica over the south pole 40m years ago. Ice pack at first formed over mountainous regions. This caused a negative temperature feedback due to the increased albedo, eventually the entire continent was covered with ice. This permanently reduced the surface temperature of the earth…..”

    Remember when quoting the Milnkovitch cycles and the cause of the ice age is that the total amount of energy reaching earth does not change, just its distribution. The drop in summer heating in the northern hemisphere even at the large dip 115,000 years ago was not enough to keep the snow from melting except in the far north of Canada. It would have lowered the snow line in the mountains but no year round snow on the plains. Models have been run that support the cycles causing ice-age but these are the same types of models a lot of us all decry when applied to global warming. I have not looked at the models so I will not say they are wrong, but I am skeptical after looking at the orbital cycles in some detail.

    http://gallery.me.com/wally#100002/60%20degree%20summer%20winter&bgcolor=black Shows the solar flux at 60° North for summer and winter and an average value over the last 20,000 years or so with the points at -115,000 years added for reference. Current summer values are more or less constant for the next several thousand years, Winter values are slowly declining and the average value is slowly declining at 60°N.

  69. Ray says:

    From the PRE-PLEISTOCENE GLACIATION plot, I’d say we are still in a cold period and it might NATURALLY get warmer in the far future http://www.acer-acre.org/ClimateChangeCD/sec4/421a.htm . But most likely, on a short time scale, it will also get colder before it gets warmer.

  70. MattB says:

    Chris Kaiser (12:15:31) :

    Milankovich theory doesn’t explain the 100k year dominant vs 43k year dominant cycles over the last few million years.

    Svensmark 2007 @ http://www.scribd.com/doc/338170/svensmark-2007cosmoclimatology does some interesting work relating our solar system’s travel through the galactic spiral arms as a modulator of cosmic rays to the big picture of ice age periods. Work in progress though.

    While I do like what I have seen of the work, I admit that I think the coorolation betwen in arm’s and out is backward. I think we would be more likely to have fewer GCR’s while in an arm as we would have not only our heliosphere but other solar systems to protect us from GCR’s (most of the higher energy ones coming from closer to the center of the galaxy). Then when we move out of the arm into more open space there is less between us and the galactic bulge and we would recieve more GCR’s. Now as for why this interglacial has been longer, if we take it my way, would be that this trip trough an arm has been longer than many others because we moved out of the Persius arm into the Orion Spur. When we move out of that we will be in open space again and here come the glaciers. If the science is sound that is.

  71. E.M.Smith says:

    Adolfo Giurfa (12:24:19) : Don’t indulge yourself, think in the siberian mammuts frozen in minutes….found with fresh food in their stomachs.

    The long term trend is very very slow. There can still be short term excursions that don’t persist. The ice cap might surge forward 10 miles in one year, yet it will only average 800 feet a year…

    That said, I have no idea what kind of process can freeze a mammoth solid in short enough time to stop digestion. It would be hard to do with commercial freezers. Something very unusual would be required, certainly not normal geologic time scale processes. Unfortunately, rocks from space make explosive heat… and a “nuclear winter” from volcanos or space rocks does not have ‘minutes’ scale onset. ’tis a mystery.

    Chris Kaiser (12:32:24) :
    It is interesting to compare this graphic of ‘65 million years of climate’:
    http://commons.wikimedia.org/wiki/File:65_Myr_Climate_Change.png

    As I read that graphic it says we are 24 C warmer 50 million years ago? But that sounds extreme… Or is that some kind of dTemp /dt that misleads as to the actual T? I don’t think I’m getting it straight…

    I found the “Antarctic Glaciation / Thawing / Reglaciation” to be a fun thought!

    Kind of makes it seem silly to worry about a “tipping point” from ice melt when we’ve already had it gone, then frozen, then a melt, and a refreeze…

    Better save a copy of the graphic quick before the AGW Langoliers “fix” it…

  72. RW says:

    “For thousands of years, people have learned from experience that cold temperatures are detrimental for human welfare and warm temperatures are beneficial”

    Strange, then, that countries on the equator are on average much poorer than countries at temperate latitudes.

    “Earth’s climate is controlled by the Sun. In comparison, every other factor is trivial.”

    The fact that an Earth without an atmosphere would be uninhabitable is not trivial.

    “Such a move in the middle of a cooling trend could provoke the irreversible onset of an ice age”

    Utter, utter, utter nonsense. This is an insane claim, which would require massive feedbacks in the climate system that only act in one direction. It is pure nonsense.

  73. rip warming says:

    I remember reading an article in wikipedia about a scientist who blamed the black death as a reason for the little ice age ie black death meant fewer people which meant less carbon dioxide…

  74. Smokey says:

    This excellent article is by the same Dr. David Deming:

    With the publication of the article in Science, I gained significant credibility in the community of scientists working on climate change. They thought I was one of them, someone who would pervert science in the service of social and political causes. So one of them let his guard down. A major person working in the area of climate change and global warming sent me an astonishing email that said “We have to get rid of the Medieval Warm Period.”[source]

    That statement, which advocates lying about established facts in order to promote an agenda, is typical of what passes for science on the CO2=AGW side. No one who makes a statement that “we” have to get rid of the MWP is being honest. Now, it’s all about the money, and who gets it.

    That quote reminds me of what Dr. Stephen Schneider stated to Discover magazine:

    “To capture the public imagination, we have to offer up some scary scenarios, make simplified dramatic statements and little mention of any doubts one might have. Each of us has to decide the right balance between being effective, and being honest.” [my emphasis]

    Was Schneider censured for advocating lying to advance the AGW=CO2 hypothesis? No; the pro-AGW side appears to lack any ethics, from top to bottom. IMHO, of course.

  75. E.M.Smith says:

    Interesting temperature chart:

    http://en.wikipedia.org/wiki/File:All_palaeotemps.png

    Though I think the last few dozen years data are a bit overstated to the warm side, it does show the LIA and the preceding climate optimum. As you go back in time, the time scale compresses, but you do get an interesting idea what the normal temperature ranges can be… including 8C higher than now
    ;-)

    The glacial periods in the ice ages show up nicely…

  76. Richard Sharpe says:

    Over on IceCap they have an article that talks about the current rapid advancement of some glacier in Alaska.

    They point to this site: GlacierResearch.

    If you just look at 30 days or even 180 days of history, you see a nice downward sloping line, indicating that the glacier is advancing towards the site where the measuring devices are, I imagine, but if you look at 365 days of history, you see a nice sine wave.

    Now, I cannot tell if the article is a parody of the usual AGW approach or the author thinks that that glacier is going to advance at 7′ per day for the next millennium, but it sure reminds me of the approach taken by AGW proponents.

    Also, as I was writing this, I noticed that the last entry on the screen said this:

    Utter, utter, utter nonsense. This is an insane claim, which would require massive feedbacks in the climate system that only act in one direction. It is pure nonsense.

    Ahhh, someone who possibly understands. I wonder if they think that about both directions of perturbation or only in the cooling direction?

  77. Putting aside the imminent ice age that may descend upon us due to the sun having a quite period(a breather?), we will end up with the practical equivalent of an ice age if the moronic politicians in various western countries are allowed to proceed with their idiotic plans for intermittent output wind farms and the like, instead of more stable output nuclear and coal burning power stations.

  78. Tom in Florida says:

    John Edmondson (14:00:45) : “To start an Ice Age, the above parameters cause a lowering of solar radiation in the NH in summer.”

    Solar radiation is more or less constant (ask Lief), I believe you are referring to solar isolation, the amount of radiation that hits a certain point on the Earth. The orbital charactaristics described by Milankovitch cycles are the prime drivers of changes in isolation. It takes the conjunction of maximum obliquity, maximum eccentricity with the NH summer solstice at perihelion to bring us out of an ice age. These three conditions coincide about every 100,000 years or so and last happened about 15,000 years ago. We are at the tail end of an interglacial period now with obliquity moving away from maximum, eccentricity changing with summer solstice moving towards aphelion. Fortunately for us, these things take time to come to pass.

  79. Pamela Gray says:

    References to the Sun driving the VARIATION are easily and mathematically falsified. I do wish this site would stop posting articles that willy nilly point to the Sun as the source of the variation. It makes us look just plain mathematically dense and neanderthal in our brain matter.

  80. Ron de Haan says:

    Noelene (11:51:54) :

    Has anybody seen the diagrams of the multi-storey buildings for growing crops?I don’t know how practical the idea is,but it seems possible.I don’t think people would starve in rich countries,but 3rd world countries would be in for a bad time,especially if the rich countries are busy providing for their people,leaving no time for 3rd world countries”.

    Noelene,

    The Multi Storage Greenhouse has been developed in the Netherlands.
    It’s a closed system and the plants float in a bath of water and fertilizer.
    No agents needed to fight insects etc.
    The concept generates it’s own energy and reduces land use.
    It’s experimental.

    The big question is if the next Ice Age will arrive with the same speed as the last one.
    The transer interval from warm to cold was very short.
    Ample time for preparation.

  81. Pamela Gray says:

    The Netherlands? Oh. That crop.

  82. Another Ian says:

    Re Smokey (15:56:49) and agendas

    There is Harry S. Truman’s comment during Watergate that went along the lines of

    When a person does wrong and knows it that’s one thing

    When a person does wrong and doesn’t know the difference that’s entirely something else

  83. Robert in Calgary says:

    OT post…..

    Regarding Ian Plimer’s book, Amazon.com tells me they’re not sure if they will have more stock.

    Amazon UK lists it as temporarily unavailable but looks to be taking orders for it.

    There is this seller in Australia….this link is in Cdn. dollars.

    http://www.connorcourt.com/catalog1/index.php?currency=CAD&main_page=product_info&cPath=7&products_id=103&zenid=594c3506cb504e2447668

  84. Ron de Haan says:

    E.M.Smith (12:22:57) :

    I don’t think it is a good idea to nuke Panama.
    It’s one of the best places to stay.
    Besides that it will have NO EFFECT if Nir Sharviv (and Svendsmark e.o) are right.
    http://www.sciencebits.com/ice-ages

  85. Pamela Gray (17:13:05) :

    References to the Sun driving the VARIATION are easily and mathematically falsified. I do wish this site would stop posting articles that willy nilly point to the Sun as the source of the variation
    Have you ever suntanned? Tanning proportional to time of exposure
    Be as simple as a kid…then wisdom will spring out of your “self”.

  86. Sandy says:

    Hmm, an ice-age would require technology to strip CO2 from the oceans to feed greenhouses.

  87. Neven says:

    This has to be one of the worst pieces I’ve read here. No mention whatsoever of Milankovitch cycles, something a geophysicist is probably acquainted with. No mention of time scales, horrific stories without reference (how widespread was cannibalism, did it occur every winter, was it a regional or global phenomenon, etc), and plain alarmism but then the other way around. Where are the skeptics tearing this abominably written piece apart?

  88. rickM says:

    I’m not sure I would trust a geologist to give an unbiased opinion on the issues with the hypothesis of AGW.

    I’m currently taking a geology course, and the professor has a Masters in geology (specializing in hydrology). She is deep into the mantra of global warming, even to tthe point in requiring us to buy a book entitled “Dire Predictions, by none other than Michael Mann. I choked my way through the required advocacy…er…reading….

    I have a tough time sitting through classes that cover the disappearing ice caps, the rising sea levels….

  89. Bob Long says:

    Re Plimer’s book, this is the publisher’s site: http://connorcourt.com/catalog1/ Currently they say “5-10 days delay”. Looks as though they have surface mail to the US; you have to click into the ordering section (or “Postage” on the left menu).

  90. James S says:

    Neven

    I agree that the piece is both alarmist and inaccurate. However I do remember , from my history lessons, that the great famine resulted in infanticide and cannabalism – these are pretty much uncontroversial history facts.

    The story of Hansel and Gretal dates back to this time, when villagers would lead children into the forest if they weren’t able to feed them themselves. Before this happened though, normally, old people would request that they were, effectively, starved so that the children could have their food.

    Cannablism was not unknown either – again due to starvation, and people would also dig up graves to find food.

    For references wikipedia is probably a start (although, as always, it isn’t a source in itself!).

  91. hotrod says:

    That said, I have no idea what kind of process can freeze a mammoth solid in short enough time to stop digestion. It would be hard to do with commercial freezers. Something very unusual would be required, certainly not normal geologic time scale processes.

    Short of dropping the mammoth in liquid nitrogen or other cryogenic fluid, it is simply not possible. A much more believable and logical explanation to me, would be that the mammoth was buried in a small snow avalanche. Wet snow avalanches set up like concrete and would smother the animal in a matter of minutes. It then would slowly freeze. A surprise snow storm that dropped deep snow cover, followed by a short thaw, where grassy patches melt out and the animals move to those areas to graze, then an avalanche buries the animal food still in its mouth. If the avalanch is small there will be no trauma to the animal, it will just be entombed in a matter of seconds.

    Other possibilities also exist such as the grazing animal was walking over a deep ice crusted snow drift in a gulley or a deep drift on the lee side of a bluff, and broke through the crust to get buried under snow collapsing into the hole.

    With the right timing of other events like a sudden cold snap and deep snow to follow, and bury the site deeply before it can melt out, and you have an animal that is entombed in ice with fresh greens in its mouth. An intense blizzard can cause snow drifts in the 20-30 ft deep range on nearly flat ground.

    Occams Razor says any one of a dozen or so similar event chains are more likely than a sudden birds fall out of the sky cold snap. That said here in the Rocky Mountains, Montana, Wyoming and Colorado all can see temperatures fall by 50 deg F in a matter of hours.

    When I was in 7th grade when we came back in from recess (sunny and temperatures in the 70′s) we were told to pack up our stuff, that they were shutting down school early and the busses would be there shortly. Two hours later is was blowing freezing drizzle, it was about 20 degrees and the roads were covered in a layer of ice that was so slick you could barely stand up when you got off the bus.

    http://en.wikipedia.org/wiki/Alberta_clipper

    If that sort of sudden cold snap happened with a starting temperature of near freezing, you could have lots of animals quickly sealed in ice and buried under deep snow drifts.

    Larry

  92. Tom in Florida says:

    Adolfo Giurfa (18:03:46) : “Pamela Gray (17:13:05) : References to the Sun driving the VARIATION are easily and mathematically falsified. I do wish this site would stop posting articles that willy nilly point to the Sun as the source of the variation.
    Have you ever suntanned? Tanning is proportional to time of exposure”

    No, tanning (or burning) is proportional to the amount of radiation your skin absorbs. Here in Florida at this time of year your burn time is anywhere from 6 to 20 minutes depending skin type. At this time in northern states it takes longer for the same amount of tanning or burning due to the angle of the sun in relation to the latitude of the person. Thus it is the shape of the Earth not the variation in the Sun that makes the difference.

  93. Pamela Gray says:

    Adolfo, were I to subscribe to your notion, my grade school teachers would rise en mass from the grave and haunt me till I die. Once again, the span of temperature variations and trends on Earth CANNOT be accounted for or correlated with the degree of measured Solar variation. On top of which, there are NUMEROUS variables right here on Earth than can and do act upon the constant of Solar heating to account for the variation and trends in temperature we experience on Earth. The Sun’s affect on the temperature trend is so small, it is buried in the standard deviation of the noise. The same is likely the case for CO2′s warming affect. Please refer to your 5th grade Science textbook for further explanation.

    I hate to ask this because I may not want to read your answer, but are you really saying that the rise and fall of the temperature anomaly throughout this interglacial period of human habitation is due to Solar variation? Working backwards from your hypothesis, which I hope you will deny, do you understand what you must force the Sun to do in order for your notion to be true? As in for example, you must move the Sun closer to the Earth and then move it back again.

    By the way, tanning depends on how much UV gets through the highly VARIABLE atmosphere. The Sun is constant (nearly so). The Earth is not. Why is this so hard?

  94. Ron House says:

    Re Ian Plimer’s book, try the publisher: http://connorcourt.com. Currently the home page says: “The book has also gone into its fifth print run.”

  95. hareynolds says:

    Carlos (08:49:19) said:
    One could also argue: Shouldn’t we try to put the missing CO2 back where it belongs whenever/however possible?

    Ironically, anyone making this suggestion can not possibly know how to DO that. I, on the other hand, DO know how to do that. I even have some patents on composite spoolable tubing which will save us from using chrome tubing. My son, a field engineer for a oilfield services company which does “pumping services” like fracturing, can run the staged frac jobs for us.

    How much are you paying per ton? As a first-order approximation, I think we can handle it for $100/ton.
    Where are you going to get the money? Which is to say, what economic dislocation are you going to perpetuate, and on whom, to get the money to pay the people (e.g. me) who know how to do this? Just curious, because folks who offer suggestions like this USUALLY want to use other folks’ money for this type of scheme. I would prefer that you get it form somewhere far away like Seattle or Boston or maybe Westchester County.

    I do have to warn you that my plan for all of this sequestered CO2 is to use it for tertiary production (so called CO2 flood) in some really old oil fields in the Permian basin, so oil production in the area is likely to go UP.
    As you can imagine, I will be charging the oil companies for the service, in addition to the $/ton that I am charging you to “sequester” your “problem”. Sorry about that.

  96. Roger Sowell says:

    All this talk of ice ages, and the adaptations required to survive reminds me that a critical issue is the lower sea level as the glaciers form. There is an interesting graph of sea level vs time on Goddard Institute for Space Studies

    http://www.giss.nasa.gov/research/briefs/gornitz_09/

    That link has a graph that shows sea level was 120 meters lower than today. That is roughly 400 feet for those (like me) who struggle with SI meters and such. (Warning: the giss author V. Gornitz has consumed the AGW kool-aid, but the graph is pretty).

    The impact on our world trade caused by sea levels that drop that far will be immense. Existing ports will be high and dry. New seaports will be required at the water’s edge, along with roads and railroads extended out to the water’s edge.

    The Straits of Malacca will be water-free, as presently they are only about 40 to 50 feet deep. Commercial shipping traffic will be re-routed accordingly.

    Those precious tidepools along California’s coast will be dry, too. I for one cannot wait to see the complete hissy fits the greenies throw over that one. (note for non-USA readers, a hissy fit is a major-league temper tantrum by humans who appear to be grown-ups). We will finally be able to drill for oil west of Santa Barbara, as it will be dry land. DRY LAND folks, no more Santa Barbara beaches to worry about.

    San Francisco Bay will be a dry valley, which will cause some problems for shipping.

    New York City will no longer have a harbor, and Long Island will likely not be an island. Chesapeake Bay may become a valley (not sure how deep the bay actually is). Miami will become an inland city, or perhaps will just build more beachfront homes further and further east as the ocean retreats. New Orleans will no longer have to worry about hurricane surges.

    These are things one never reads about, instead, the AGWers have monopolized the governmental concern with how to contend with a few feet of sea level rise. How’s about assessing the needs for a 400-foot sea level drop? And who is to say there will be only 400 foot drop this time? We could be in for a humdinger of an ice age, with 500 foot or more drop in sea level.

  97. Allan M R MacRae says:

    from Shaviv and Veizer (GSA Today 2003) re the cause of Ice Ages::

    ABSTRACT
    Atmospheric levels of CO2 are commonly
    assumed to be a main driver of
    global climate. Independent empirical evidence
    suggests that the galactic cosmic
    ray flux (CRF) is linked to climate variability.
    Both drivers are presently discussed
    in the context of daily to millennial variations,
    although they should also operate
    over geological time scales. Here we analyze
    the reconstructed seawater paleotemperature
    record for the Phanerozoic (past
    545 m.y.), and compare it with the variable
    CRF reaching Earth and with the
    reconstructed partial pressure of atmospheric
    CO2 (p2).

    NOTE HERE

    We find that at least
    66% of the variance in the paleotemperature
    trend could be attributed to CRF variations
    likely due to solar system passages
    through the spiral arms of the galaxy.
    Assuming that the entire residual variance
    in temperature is due solely to the CO2
    greenhouse effect, we propose a tentative
    upper limit to the long-term “equilibrium”
    warming effect of CO2, one which is potentially
    lower than that based on general
    circulation models.
    __________________________

    There was an attempt to shout down Veizer and Shaviv, especially in the journal EOS. To my knowledge, that attempt failed.

    Regards, Allan

  98. Francis says:

    A warning, about not heeding a warning; seems out of place here, somehow.

    When I sat in a geology classroom, Continental Drift was only a theory. There were many good arguments for it. But it hadn’t been proven yet.

    Milankovitch, a Serbian school teacher, proved (using logarithms!) that the small orbital changes could explain the ice ages.

    Last I heard, we will have another 16,000 years in our interglacial. And that’s easily extended, with just a little global warming.

  99. Lark says:

    E.M.Smith (12:22:57) :
    Also realize that ice ages START fast (in geologic terms) but the ice proceeds to grow more or less linearly (with wobbles) for 100,000 years. … If you walk 801 feet south each year, you outrun the ice age… (call it 250 meters…)

    I don’t think so. Only the growth up (accumulation) of the ice cap would be semi-linear. Most of the outward growth would be nearly immediate – (non-coastal) Canada could be gone in a year (the mammoth-freezing scenario) to a few decades, depending on circumstances. I expect ADM would soon be getting taxpayer subsidies for high-protein blackflies from the Iowa tundra/taiga.

    I can think of one thing with linear outward growth in the sense you describe – every year, more continental shelf will be exposed as more ocean evaporates and is deposited on the ice caps.

  100. edward says:

    Milankovitch is pretty well validated IMHO, but it takes both eccentricity and obliquity to be in phase to get the stable, lower temperature interglacial that we have enjoyed for so long. This last one has been very beneficial for mankind I’d say. The current interglacial and the one that occurred ~420kyrs are very similar (both in phase).

    ~225000 yrs ago Eccentricity and Obliquity were well out of phase and the result was some pretty unstable climate (essentially the eccentricity cycle was split in two with dual interglacials as a result). Really screws with FFTs. Not great times for mankind I would think.

    If you average the GISP2 data and the Vostok data, and consider it to be representative of global temps, it looks like we have been entering the next ice age for the last 3500yrs roughly, with about the same rate of change (ignore the ~1200yr cycle/noise we are currently experiencing which are similar and probably share the same periodicity as the MWP, Roman WP, etc).

    Looking at the longer term, millions of years, definitely a cycle there (~150million yrs), I would assume galactic due to the time scales, I’d be a little surprised that continental drift would be so cyclic.

  101. Ray B says:

    I will admit that I am a student of climate change, (Younger-Dryas, Bond events, Dansgaard-Oeschger events, etc.), and as a bad sci-fi fan, I even like the movie the day after tomorrow. I don’t believe for a second that a movie style absolute zero wave came through and froze stuff in place. The unfortunate mammoth more likely fell down a ravine, through a hole in the ice, or was entombed in an avalanche as suggested above.

    On the other side of it though, I don’t buy into the 100,000 year gradual change thing either. The blue marble is a violent place, and significant climate change can occur in well under a century. The thought of present day society experiencing an event similar to Younger-Dryas scares me a lot more that AGW.

    It is really a shame that academia and others are filling our population’s heads with AGW fear mongering and garbage. My climate change studies are immensely more interesting, pondering how a mile-thick glacier melted so fast that it left a pile of outwash that is now a steep ski hill, or checking out sedimentary rocks where a glacier bowled over an ancient forest..

    If you want fear about climate, go study the Volstok cores, and do a YOU ARE HERE —>.

    We should consider ourselves lucky to have lived in the Modern Maximum with such a nice climate. While it might not seem like it sometimes, these ARE the good old days.

  102. Jim says:

    “The Great Famine was followed by the Black Death, the greatest disaster ever to hit the human race. One-third of the human race died; terror and anarchy prevailed. ”

    Well not exactly. The Black Death was a European phenomenon. One third of people died there. The rest of humanity was blissfully unaware of the problem.

  103. Steven Hill says:

    It’s all wrong, Gore stated that we are like frogs in heating water just waiting to be boiled alive. Ice?, what are you people thinking? The Hansen models are showing the planet is on the tipping point of extream heat! CO2 must go, we need to limited population, stop economic growth and lie down and slow our breathing. Get real, we are all going to die from heat exhaustion!!!! Stop CO2 now!

    LOL

    Cap and Tax, Cap and Tax, Cap and Tax!

    Free health care for all!

    Free Electric Cars!

    Windmills!

    Solar Panels for all!

    Robinhood policies, spread the wealth! Rob the Rich and give to the poor!

  104. Steve M. says:

    Rhys:

    I can’t believe that you couldn’t live in Tanzania during an ice age. Mightn’t be as hot, but it’d sure be well above freezing. Ditto India. Ditto Australia. Ditto Brazil.

    Ice and extreme desert covered much of the earth during the last glacial period:

    http://www.geocraft.com/WVFossils/last_glacial_max.html

    It may be above freezing, but hardly will it support life.

  105. idlex says:

    Francis wrote: Milankovitch, a Serbian school teacher, proved (using logarithms!) that the small orbital changes could explain the ice ages.

    Does anyone know how he calculated it? If he did it using logarithms, I figure I could do it a lot easier on my computer.

  106. MartinGAtkins says:

    By reducing our production of carbon dioxide, we risk hastening the advent of the next ice age.

    Stuffing nonsense. We risk inducing poverty and it’s all its associated horrors. There is no danger of mankind removing all the carbon dioxide from our atmosphere.

  107. Mr Lynn says:

    E.M.Smith (15:20:33) :

    . . . That said, I have no idea what kind of process can freeze a mammoth solid in short enough time to stop digestion. It would be hard to do with commercial freezers. Something very unusual would be required, certainly not normal geologic time scale processes. Unfortunately, rocks from space make explosive heat… and a “nuclear winter” from volcanos or space rocks does not have ‘minutes’ scale onset. ’tis a mystery. . .

    Well, waiting in the wings there’s always Velikovsky, who proposed that the Earth was knocked sideways by a young Venus (newly-sprung from Jupiter), on her way to her present orbit, events he maintained were enshrined in ancient myths and recorded in geological catastrophes (see Worlds in Collision, Earth in Upheaval). The placid mammoths chewing their cuds were suddenly plunged into the deep freeze that Siberia became. Not very plausible, given the accepted geological record, but an interesting speculation, nonetheless.

    Horatio: O day and night, but this is wondrous strange!
    Hamlet: And therefore as a stranger give it welcome.
    There are more things in heaven and earth, Horatio,
    Than are dreamt of in your philosophy.
    —Hamlet Act 1, scene 5, 159–167

    /Mr Lynn

  108. Pamela Gray (20:11:54) : I just wanted to tell you that, OK, the TSI it is almost invariable BUT there are a few things in between that make for changes (clouds, ozone, etc) which are AGAIN caused by our OLD SUN’s behaviour.
    There are small things which are meaningful, like the blink of an eye, for example.

  109. Barbara says:

    Several people have pointed out that we are still technically in an Ice Age (ice at the poles), in an interglacial.
    Slightly more unsettling possibility – that we are in an *interstadial*.
    Interstadial = shorter, warmer phase of a glaciation (not warm or long enough to qualify as a full interglacial).

    Average length of an interstadial : approx 10,000 years.
    Time since ice sheets last retreated (c.8300 BC to present): approx 10,000 years.

    :-O

  110. Ron de Haan says:

    idlex (18:05:14) :

    “This might be relevant/interesting:

    Global land environments since the last interglacial”

    idlex, thanks for the link.
    Very interesting!

  111. Worst than that:

    Barbara (08:13:50) :

    An often-cited 1980 study by Imbrie and Imbrie determined that “Ignoring anthropogenic and other possible sources of variation acting at frequencies higher than one cycle per 19,000 years, this model predicts that the long-term cooling trend which began some 6,000 years ago will continue for the next 23,000 years.”
    http://www.statemaster.com/encyclopedia/Milankovitch-cycles#The_future

  112. OT: “Watts Effect” urgently needed!!. Is it a spot or just a lost pixel?

  113. Ron de Haan says:

    Roger Sowell (21:19:48) :

    “All this talk of ice ages, and the adaptations required to survive reminds me that a critical issue is the lower sea level as the glaciers form. There is an interesting graph of sea level vs time on Goddard Institute for Space Studies

    http://www.giss.nasa.gov/research/briefs/gornitz_09/

    That link has a graph that shows sea level was 120 meters lower than today. That is roughly 400 feet for those (like me) who struggle with SI meters and such. (Warning: the giss author V. Gornitz has consumed the AGW kool-aid, but the graph is pretty).

    The impact on our world trade caused by sea levels that drop that far will be immense. Existing ports will be high and dry. New seaports will be required at the water’s edge, along with roads and railroads extended out to the water’s edge.

    The Straits of Malacca will be water-free, as presently they are only about 40 to 50 feet deep. Commercial shipping traffic will be re-routed accordingly.

    Those precious tidepools along California’s coast will be dry, too. I for one cannot wait to see the complete hissy fits the greenies throw over that one. (note for non-USA readers, a hissy fit is a major-league temper tantrum by humans who appear to be grown-ups). We will finally be able to drill for oil west of Santa Barbara, as it will be dry land. DRY LAND folks, no more Santa Barbara beaches to worry about.

    San Francisco Bay will be a dry valley, which will cause some problems for shipping.

    New York City will no longer have a harbor, and Long Island will likely not be an island. Chesapeake Bay may become a valley (not sure how deep the bay actually is). Miami will become an inland city, or perhaps will just build more beachfront homes further and further east as the ocean retreats. New Orleans will no longer have to worry about hurricane surges.

    These are things one never reads about, instead, the AGWers have monopolized the governmental concern with how to contend with a few feet of sea level rise. How’s about assessing the needs for a 400-foot sea level drop? And who is to say there will be only 400 foot drop this time? We could be in for a humdinger of an ice age, with 500 foot or more drop in sea level”.

    The reduced sea level could compensate for the land loss due to glaciation.

    Because the drop in sea levels will be a slow process we will have sufficient time to adapt.
    It takes about 30 years to transform a former sea bed into land suited for agriculture
    (based on experience in the Netherlands when the former Southern Sea was turned into a sweet water reservoir and than was turned into land.
    The former sea floor (sea clay) has turned into rich agricultural land producing high yield harvests).

    Infra structural projects can be performed relatively fast as it took us an ample 150 years to build the current infra structure with the biggest advances during the last 60 years. We would see the introduction of the so called “White” or “Cool” jobs at a scale never seen in human history to adapt our societies to the coming glaciation as we would see the biggest migration in human history as people move from the North to the South.

    Anyhow, the social economic effects of such an event certainly would dwarf that of the current “Green Jobs” program of Obama.

    It makes a person very humble to see that the real “change” is initiated by nature and not by man.

  114. Ron de Haan says:

    OT
    Just for who is interested, an incredible picture of Chaitén Volcano is published at
    http://www.seablogger.com/?p=14273

    I am watching the developing events of this volcano since it’s unexpected eruption the second of may 2008 via the Chaitén Airport web cam looking North and the assessment reports published at several web sites.

    I think this volcano is going to cause a major eruption in the near future, shooting a lot of material into the troposphere with a lot of potential “cooling” in the process, despite it’s geographic location on the Southern part of Chili.

    Dome building takes place at an incredible speed, lava has risen to the rim of the dome which is very unstable.
    Quakes up to magnitude 4.2 are registered between 0.5 and 12 km directly under the volcano. Smaller quakes that mark the outer boundaries of the caldera show it’s huge. The separate vents now have grown together to form a wide vent reducing the pressure build up and limiting the plume to altitudes around 2 to 2.5 km.

    This can change abruptly in case of a major dome collapse.
    The town of Chaitén, still habited by a small group of about sixty people, persistent to “save their hometown”, will be wiped from the face of the earth.

    This volcano represents the equivalent of a nuclear reactor in a cart box.

  115. Ron de Haan says:

    Francis (22:15:18) :

    “A warning, about not heeding a warning; seems out of place here, somehow.

    When I sat in a geology classroom, Continental Drift was only a theory. There were many good arguments for it. But it hadn’t been proven yet.

    Milankovitch, a Serbian school teacher, proved (using logarithms!) that the small orbital changes could explain the ice ages.

    Francis,
    Last I heard, we will have another 16,000 years in our interglacial. And that’s easily extended, with just a little global warming.”

    You must have been in the local pub with the heating up and doors and windows closed when you heard so, because I haven’t noticed any global warming lately.

  116. Roger Sowell says:

    From London’s Financial Times today:

    “One of the most alarming consequences of rapid global warming would be a collapse of the west Antarctic ice sheet. Until now scientists have generally assumed that it would raise the global sea level by five to six metres, but a more detailed analysis, published in the journal Science, shows this is an overestimate.

    The study, led by Jonathan Bamber, of Bristol University, found that a complete collapse would raise the sea level by an average of 3.3 metres – though the rise would not be distributed evenly around the world. The biggest impact would be along the Atlantic and Pacific coasts of north America, where levels would rise 25 per cent more than the global average.

    The regional variations result from the uneven redistribution of ice from Antarctica into the oceans. With less mass around the South Pole, Earth’s gravitational field would become slightly weaker in the southern and stronger in the northern hemispheres, causing water to pile up in the north. The redistribution of mass would also affect the planet’s rotation, accentuating the sea level rise in the western hemisphere.”

    http://www.ft.com/cms/s/0/5e6810a2-4098-11de-8f18-00144feabdc0.html?nclick_check=1

  117. DaveE says:

    “hareynolds (20:57:11) :

    Carlos (08:49:19) said:
    One could also argue: Shouldn’t we try to put the missing CO2 back where it belongs whenever/however possible?”

    I think that Carlos meant put it back in the atmosphere!

    DaveE

  118. Pamela Gray says:

    Adolfo, do you know how much ozone would have to disappear (and then reappear) in order to make a drop in the bucket difference in the global temperature trends? And do you know how much more cosmic rays would have to change in order to affect cloud formation to the degree that it affects global temperature? On the other hand, do you know how much SST’s have to change in order to change weather patterns? This seems such a no brainer to me. I still don’t understand why you focus on the Sun when all around you are variables that perfectly explain weather pattern trends.

  119. Roger Sowell says:

    Re my 14:22:27 comment, how can this re-evaluation of the sea level rise be accurate? Isn’t the science settled? (settled: verb, past-tense of “settle;” meaning no longer in doubt). Yet, here we have a new study (doesn’t sound settled to me; why conduct a new study, if the science is settled)?

    Also, this article states that “until now, scientists have generally assumed that…” and sea level would rise “five to six meters;” none of which satisfies the concept of “settled science.” [bolding mine] So, is settled science based on assumptions? And estimates with a range of 20 percent (six is 20 percent more than five)? If the engineers used such “settled” results for engineering calculations, the first woodpecker that came along would destroy civilization.

    Ah well. Perhaps with all that extra Antarctic ice these days, one could expect the sea level rise to be less…. oh wait…wouldn’t MORE ice equate to MORE sea level rise? Never mind…I am sure that this is also part of the science that is settled.

    Last point, I wonder if Mr. Bamber has consulted lately with the sea level rise charts
    , and considers the fact that the sea off the west coast of North America is in fact falling, not rising. One must then wonder exactly how the Antarctic ice melt will all rush over to Baja California, and up the coast to Monterrey, and hang out there. I would appreciate a lucid explanation for this phenomenon.

  120. Ron de Haan says:

    Who is interested in a Plimer Presentation about “Climate Change” can have a look here: http://www.tsaugust.org/Weekly_News.htm#Curb_

  121. Ron de Haan says:

    Roger Sowell (18:08:37) :

    “Re my 14:22:27 comment, how can this re-evaluation of the sea level rise be accurate? Isn’t the science settled? (settled: verb, past-tense of “settle;” meaning no longer in doubt). Yet, here we have a new study (doesn’t sound settled to me; why conduct a new study, if the science is settled)?”

    Roger,

    Why don’t you send your comments to FT and Mr. Bamber and a claim for fraudulant science to the University of Bristol.
    I am sure that Monckton will give you a helping hand.

  122. David Deming says:

    As the author of this piece, I’m gratified at the attention it has received. The comments here have raised a couple of concerns. (1) Was I exaggerating about people “eating their children,” during the Great Famine of 1315? No, my sources were from articles published in the peer-reviewed scholarly literature that were based on contemporary chronicles. (2) Has Milankovitch Theory been “falsified”? Maybe. In Popper’s “Logic of Scientific Discovery,” he concedes that absolute falsification is an impossibility. But I’m writing here a polemic, albeit one based on facts and the scientific literature. In a polemic, one has to make certain compromises. For example, you just don’t have the space to list nuances and provide counter-arguments.

    I’m glad I produced a piece that people found interesting. I don’t believe we yet have a good or thorough understanding of the Earth’s climate system.

  123. Francis T. Manns says:

    Continental shelf edges might represent the 90% probable shoreline.

  124. Francis says:

    Ron de Haan (13:30:25) re: CURRENT COOLING ?

    Local weather is pretty simple here: heating season and air conditioning season, separated by nice weather. I only pay attention to outside temperatures mid-month, when last month’s global average becomes available.

    From the Summary of the April, 2008; Fawcett & Jones paper: Waiting for Global Cooling. (This is Aussie–I like the accent.)

    There is very little justification for asserting that global warming has gone away over the past ten years, not least because the linear trend in globally-averaged annual mean temperatures (the standard yardstick) over the period 1998-2007 remains upward. While 1998 was the world’s warmest year in the surface-based instrumental record up to that point in time, 2005 was equally warm and in some data sets surpassed 1998. A substantial contribution to the record warmth of 1998 came from the very strong El Nino of 1997/1998 and, when the annual data are adjusted for this short-term effect (to take out El Nino’s warming influence) the warming trend is even more obvious.

    Because of the year- to-year variations in globally-averaged mean temperatures, about ten years are required for an underlying trend to emerge from the “noise” of those year-to-year fluctuations. Hence, the fact that 2006 and 2007 were cooler than 2005, is nowhere near enough data to clearly establish a cooling trend.

    And of course this most recent La Nina continued, thru 2008, until it ended last month.
    I would hope for some standard weather for a while…so we can keep score without the down and up adjustments.

  125. John Finn says:

    Smokey (15:56:49) :

    This excellent article is by the same Dr. David Deming:

    …. So one of them let his guard down. A major person working in the area of climate change and global warming sent me an astonishing email that said “We have to get rid of the Medieval Warm Period.”

    Is there any reason why the “major person” cannot be named?

  126. Chuck Bradley says:

    I hope this helps on a few points raised in this discussion.
    “Heaven and Earth” will be published on different dates in different countries.
    It initially appeared in Australia. I have read it is available in NZ.
    The last information I saw, claimed US publication was scheduled for May 28,2009.
    Brian Fagen’s “The Great Warming” claimed extensive cannibalism during the little ice age. Families swapped children so they would not have to eat their own.
    Fishermen in modern times report nets snagged on trees on the sea floor at Grand Banks and Georges Banks; trees confirmed by divers.

  127. Ron de Haan says:

    Francis (21:40:32) :

    Ron de Haan (13:30:25) re: CURRENT COOLING ?

    Local weather is pretty simple here: heating season and air conditioning season, separated by nice weather. I only pay attention to outside temperatures mid-month, when last month’s global average becomes available.

    From the Summary of the April, 2008; Fawcett & Jones paper: Waiting for Global Cooling. (This is Aussie–I like the accent.)

    There is very little justification for asserting that global warming has gone away over the past ten years, not least because the linear trend in globally-averaged annual mean temperatures (the standard yardstick) over the period 1998-2007 remains upward. While 1998 was the world’s warmest year in the surface-based instrumental record up to that point in time, 2005 was equally warm and in some data sets surpassed 1998. A substantial contribution to the record warmth of 1998 came from the very strong El Nino of 1997/1998 and, when the annual data are adjusted for this short-term effect (to take out El Nino’s warming influence) the warming trend is even more obvious.

    Because of the year- to-year variations in globally-averaged mean temperatures, about ten years are required for an underlying trend to emerge from the “noise” of those year-to-year fluctuations. Hence, the fact that 2006 and 2007 were cooler than 2005, is nowhere near enough data to clearly establish a cooling trend.

    And of course this most recent La Nina continued, thru 2008, until it ended last month.
    I would hope for some standard weather for a while…so we can keep score without the down and up adjustments”.

    Francis,

    The point is that there is no reason at all for any of the warming alarmism.
    Everything that happens today, has happened hundreds of times in the past.
    We have had much higher temperatures and much higher CO2 and never experienced scary things like dangerous run away warming and all the other fear mongering the AGW scare mongers are dishing up only to serve a political agenda.

    To reduce our CO2 emissions by 80% based on 1990 levels by 2050 as demanded by the UN is a joke and it will never happen.

    It’s a matter of time before the shoe will drop and heads will role.

  128. Francis says:

    Ron de Haan (15:32:02)
    “Everything that happens today has happened hundreds of times in the past. We have had much higher temperatures and much higher CO2…”

    I’m just winging it now…I’ve gotta go do the laundry and buy the groceries, etc….so I can’t double check anything…But, a list of the above would be a potent argument against AGW.

    The hockey stick graphs (that don’t list Michael Mann among the authors…to avoid that discussion) don’t show any such events…in the past 1000 years.

    There is a medieval warm period in those graphs…but it doesn’t match current warming.

    The global warming portion of the hockey stick graph would be that after about 1975…note how steep the slope is.

    Geological time on this would probably start when South America butted up against North America…in order to get similar continental layouts…whenever that was. And periods of mass extinctions would be inappropriate.

    No doubt my skepticism (in the general sense) shows thru this exposition. But I have encountered a number of such historical/glacial/geological arguments…are there any that are any good?

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