Good news! Elevated CO2 may extend interglacial, prevent next ice age

Those ice sheets again

Those ice sheets again (Photo credit: swan-scot)

Reader “Markx” writes in Tips and Notes on a paper I hadn’t noticed before (because it was published before WUWT was born). Of course it only works if CO2 has a long residence time and/or our elevated emission levels continue. We need at least 3x more CO2 to pull off the delay.

A movable trigger: Fossil fuel CO2 and the onset of the next glaciation. David Archer and Andrey Ganopolski

Published in G3 Geochemistry Geophysics Geosystems Research Letter Volume 6, Number5 5 May 2005

Abstract:

The initiation of northern hemisphere ice sheets in the last 800 kyr appears to be closely controlled by minima in summer insolation forcing at 65N. Beginning from an initial typical interglacial pCO2 of 280 ppm, the CLIMBER-2 model initiates an ice sheet in the Northern Hemisphere when insolation drops 0.7 s (standard deviation) or 15 W/m2 below the mean. This same value is required to explain the history of climate using an orbitally driven conceptual model based on insolation and ice volume thresholds (Paillard, 1998). When the initial baseline pCO2 is raised in CLIMBER-2, a deeper minimum in summertime insolation is required to nucleate an ice sheet. Carbon cycle models indicate that 25% of CO2 from fossil fuel combustion will remain in the atmosphere for thousands of years, and 7% will remain beyond one hundred thousand years (Archer, 2005). We predict that a carbon release from fossil fuels or methane hydrate deposits of 5000 Gton C could prevent glaciation for the next 500,000 years, until after not one but two 400 kyr cycle eccentricity minima. The duration and intensity of the projected interglacial period are longer than have been seen in the last 2.6 million years.

Some excerpts:

“Models require some amplifying feedback, from sea ice … or the terrestrial biosphere ….to nucleate on the basis of insolation forcing, but insolation is always the primary driver.”

and

An anthropogenic release of 300 Gton C (as we have already done) has a relatively small impact on future climate evolution, postponing the next glacial termination 140 kyr from now by one precession cycle.

Release of 1000 Gton C … is enough to decisively prevent glaciation in the next few thousand years, and given the long atmospheric lifetime of CO2, to prevent glaciation until 130 kyr from now.

If the anthropogenic carbon release is 5000 Gton or more….[...]… The model predicts the end of the glacial cycles, with stability of the interglacial for at least the next half million years…

Archer_GT_of_Co2-insolation

Figure 3. Effect of fossil fuel CO2 on the future evolution of climate. Green represents natural evolution, blue represents the results of anthropogenic release of 300 Gton C, orange is 1000 Gton C, and red is 5000 Gton C. (a) Past and future pCO2 of the atmosphere. Past history is from the Vostok ice core [Petit et al., 1999], and future anthropogenic perturbations are from a carbon cycle model [Archer, 2005]. (b) June insolation at 65N latitude, normalized and expressed in s units. 1 s equals about 20 W m2. Green, blue, orange, and red lines are values of the critical insolation i0 that triggers glacial inception. The i0 values are capped at 3 s to avoid extrapolating beyond model results in Figure 3; in practice, this affects only the 5000 Gton C scenario for about 15 kyr. (c) Interglacial periods of the model. (d) Global mean temperature estimates.

Not having mile thick ice sheets crush northern hemisphere cities is a good thing, don’t you think?

Full PDF here: http://geosci.uchicago.edu/~archer/reprints/archer.2005.trigger.pdf

About these ads

110 thoughts on “Good news! Elevated CO2 may extend interglacial, prevent next ice age

  1. I have read that the only way to get us out of the Ice Age, in which we currently live and have so lived for that last 2.5 million years, is to remove the Isthmus of Panama. CO2 does not come into play with this equation at all.

  2. In his book, “Coal Trains of Death” Hansen says that the output from a single chlorofluorocarbon plant is enough to prevent an ice age.

  3. “Good news! Elevated CO2 may extend interglacial, prevent next ice age

    That could be wishful thinking.

  4. “Not having mile thick ice sheets crush northern hemisphere cities is a good thing, don’t you think?”

    Think of all the shoveling we would save…

  5. While it is refreshing to read someone at least trying to take an objective look at climate change rather that screaming about catastrophe, I don’t put any more faith in this model than I do the IPCC’s various models and only slightly more than a sheep’s entrails.

    We are a long way yet from understanding what is going on to an extent that allows us to model climate. There are waaayy too many exceptios probing the regnums.

  6. I vaguely recall that during the late Ordovician Co2 was over 4,000 parts per million. (Today 400ppm).

    I vaguely recall during the late Ordovician there was an ice age.

    I vaguely recall that Co2 remained at over 3,000 ppm throughout the glaciation.

    C02 is a magical gas. ;)

  7. The length of the Holocene without any CO2 in the graph above seems unusually long. Is this reasonable? Doesn’t the paleo record show that inter-glacials have all been quite short? In the absence of CO2, why expect this time be different?

    It seems more likely that the prediction of the lengthy, non CO2 interglacial is wishful thinking, in support of limiting CO2 production for political and economic advantage. If we are on the edge of slipping into the next ice age, then CO2 may provide the only hope for the future of many of the cities and peoples of the world.

    Otherwise, we are left with the 1950’s alternative. Building thousands of nuclear power plants to heat the oceans, and/or thousands of gigantic solar reflectors in space to warm the land.

  8. oh good grief…this was 8 years ago
    …science has progressed since then

    Now we know that it causes wet/dry, warm/cold, snow/rain, freeze/heat, drought/flood, and earthquakes………….

  9. It’s funny how our dangerous level of co2 at well above the safe limit of 350ppm could not prevent the 15 year global temperature standstill (slight 10 years of cooling), but at higher levels is sufficient to prevent another ice age.

    We need at least 3x more CO2 to pull off the delay.

    10 times more co2 failed to do this.

  10. The model appears to be based on a climatic sensitivity to CO2 that is typical of the beliefs of the warmist fraction.

    It is thus quite possible that the CO2 will have as trivial an effect on the next glacial as it is having this past decade (and more) on global average temperatures.

  11. I think the next bond event will probably start the next glaciation. Its due soon geologically speaking so maybe fun for all.

    CO2 will not stop a glaciation because as the oceans cool they will suck up CO2 from the atmosphere.

  12. The problem with the CO2 warming hypothesis is that if makes Ice Ages and Interglacials impossible. We know that the oceans release CO2 as they warm. Thus Interglacials make the next Ice Age impossible. We know that oceans absorb CO2 as they cool. Thus Ice Ages make the next Interglacial impossible.

    However, we know that Ice Ages and Interglacials happen regularly, with only a very slight change in solar energy reaching the earth due to orbital mechaniscs. So, either the paleo records are wrong, or the CO2 warming hypothesis is wrong.

  13. Gosh it appears that people have not noticed that we are near the end of the present interglacial and that it has been cooling for around 4,000 years now.

    Here once again are some references to charts which are based on empirically based published science papers using actual and credible proxies.This is from Chapter 8-10 of his book and linked to his website:

    http://theinconvenientskeptic.com/chapters-8-10/

    Go there and see that this interglacial period is almost over and called the Autumn phase at this point of history.

  14. Jimbo says:
    April 27, 2013 at 7:22 am
    ———————————————-
    And from the same site

    IF the plant stomata proxies are more accurate than the ice core ones it`s possible co2 levels from previous interglacials were a lot higher than indicated , then it means the rating of the glacial delaying effect from CO2 would drop from “BB gun Vs charging elephant” to “pop gun” rating .

  15. Byron says:
    April 27, 2013 at 8:01 am
    IF the plant stomata proxies are more accurate than the ice core ones it`s possible co2 levels from previous interglacials were a lot higher than indicated
    =========
    that would explain the inconsistency between glacial cycles and CO2 levels. it would indicate that today’s CO2 levels are consistent with past CO2 levels during interglacials, and that warming, not SUV’s, is the cause of CO2. Or, that CO2 is the result of widespread land use change over the past 100 years.

  16. The claims in the paper are completely preposterous. First, even if the CO2 doubling caused (sensitivity) of 2 Celsius degrees, one would need four doublings to get 8 °C to neutralize an ice age – sixteen times larger concentrations of CO2.

    But this mistake is negligible relatively to the residence time. We will probably run out of – or stop using fossil fuels – within 300 years or much less. Within two more centuries, a vast majority of the excess CO2 will be reabsorbed again. There’s no way how we could affect temperatures in the future that is as distant as 5,000 years – first moment when a credible sign of a new ice age might potentially occur.

    Moreover, the true new local minimum ice age will arrive in 60,000 years or so and that’s much further:

    http://motls.blogspot.com/2012/03/next-peak-of-ice-age-year-60000-ad.html?m=1

    The excess CO2 above the temperature-dictated equilibrium (now 280 ppm) is decreasing exponentially with time with the halving time currently shorter than a century (it may be a bit longer when life is mostly frozen and slowly reacts to the changes). It’s easy to see why it’s so. We’re emitting the equivalent of 4 ppm of CO2 in the atmosphere every year but the concentration only grows by 2 ppm. So the remaining 2 ppm are absorbed. They are absorbed *because* the CO2 is elevated so the consuming processes are strengthened. They would be strengthened even if we didn’t emit any CO2 because these ocean and life processes don’t care about the emissions in the last year – they only care about the immediate CO2 concentration in their vicinity. So the concentration would begin to drop by 2 ppm a year if we stopped making any emissions tomorrow.

    From any realistic concentration – 2,000 ppm, if you wish – we would be back below 300 ppm within at most a few centuries.

  17. To make a prediction it is necessary to know the planet’s sensitivity to a doubling of CO2 (Very low unfortunately, it appears a doubling of atmospheric CO2 will warm the planet less than 1C) and to understand what causes the glacial/interglacial cycle. If I understand the mechanisms that control the glacial/interglacial cycle, the increase in atmospheric CO2 will not inhibit the start of the next interglacial. The current orbital position is optimum for terminating this interglacial period, if the below mechanism is what terminates interglacial periods. The current observations appear to support the assertion that we are going to experience what causes either a Heinrich event or a Dansgaard-Oeschger cycle. I will if and when there is the start of unambiguous global cooling make a formal presentation to explain the mechanisms and what to expect next.

    An analysis of geomagnetic dipole lows and related geomagnetic excursion over the last 800k years from (the Sint-800) deep sea floor analysis data base shows that 12 of the interglacial terminations correlate with geomagnetic excursions. It is asserted that geomagnetic excursion is what terminates the interglacial not insolation at N65 in July and August. If that assertion is correct, the next question is what causes the cyclic geomagnetic excursions?

    http://openearthsystems.org/data/readings/Open%20Earth%20Library-%20Topical%20Folders/Core%20Dynamics/Thouveny%20et%20al%202008.pdf

    See table 2 in this paper.
    Paleoclimatic context of geomagnetic dipole lows and excursions in the Brunhes, clue for an orbital influence on the geodynamo?

    An observation to support the above assertion (that insolation at 65N in July and August does not control the glacial/interglacial cycle) is the Younger Dryas abrupt cooling event that occurred 12,900 years ago. 12,900 years ago, insolation at N65 in July and August was close to the peak for the Holocene interglacial period. Then some external forcing function created a geomagnetic excursion which in turn caused the planet to return to glacial cold for a period of 1000 years with 70% of the cooling occurring in less than a decade. The logic point is the geomagnetic excursion is the 800 pound gorilla, the massive forcing function which can make it cold in both summer and winter which causes the ice sheets to form and grow or vice verse as the massive forcing function can ultimately strengthen geomagnetic field which causes the planet to be warmer in both winter and summer. The external forcing function terminates and initiates the interglacial periods by inhibiting or strengthening the geomagnetic field.
    The authors of the above paper speculated that orbital changes somehow caused the geomagnetic lows. That speculation is not correct. The mechanism, the forcing function that causes cyclic abrupt changes to the geomagnetic field is a restart of the solar magnetic cycle after it has been interrupted. There are burn marks on the surface of the planet that correlate with Younger Dryas abrupt cooling period (the duration of the Younger Dryas cooling event is roughly 1000 years). There are burn marks on the planet’s surface that correlate with other geomagnetic excursions.

    What controls whether the massive discharge from the sun ultimately attempts to reverse or strengths the geomagnetic field is the orbital position when the event occurs. Greater orbital eccentricity and orbital tilt amplifies the mechanism in how much the strikes affects the geomagnetic field strength. Whether the Northern Hemisphere or the Southern Hemisphere is in summer or winter (point towards or away from the sun at perihelion – closest point to the sun) determines whether the strikes ultimately strengthen or attempt to reverse the geomagnetic field. In all cases the strike temporary reduces the intensity of the geomagnetic field as the field in the core resists a field change. Then over time equilibrium is reached as current flows through the earth attempting balance charge on the surface with the core.

    In the last 10 years geomagnetic specialists have discovered and reached consensus that the geomagnetic field has in the past abruptly changed (the speed of the change and the number of the changes is orders of magnitude higher than previous assumptions based on the theoretical origin of the geomagnetic field and the theoretical origin of geomagnetic field changes) and that the changes correlate with climate changes.

    There are two types of observed rapid geomagnetic field changes: 1) archeomagnetic jerks at which time the geomagnetic field axis abruptly changes by 10 to 15 degrees and 2) geomagnetic excursions which is a failed or very short lived reversal at which time the intensity of the geomagnetic field drops by a factor of 5 to 10. The geomagnetic field specialists have multiple hypotheses to try to explain why the geomagnetic field is abruptly changing.

    An observation that supports the assertion that solar changes modulate the geomagnetic field and that we are going to experience either a D-O cycle or a Heinrich event is the sudden unexplained increase in the North geomagnetic pole drift velocity by a factor of 4 to 5 starting in 1990’s which correlates with the inhibiting of Svensmark’s GCR mechanism.

    http://onlinelibrary.wiley.com/doi/10.1029/2010EO510001/pdf

    What Caused Recent Acceleration of the North Magnetic Pole Drift?
    The north magnetic pole (NMP) is the point at the Earth’s surface where the geomagnetic field is directed vertically downward. It drifts in time as a result of core convection, which sustains the Earth’s main magnetic field through the geodynamo process. During the 1990s the NMP drift speed suddenly increased from 15 kilometers per year at the start of the decade to 55 kilometers per year by the decade’s end. This acceleration was all the more surprising given that the NMP drift speed had remained less than 15 kilometers per year over the previous 150 years of observation. … ….Why did NMP drift accelerate in the 1990s? Answering this question may require revising a long-held assumption about processes in the core at the origin of fluctuations in the intensity and direction of the Earth’s magnetic field on decadal to secular time scales, and hints at the existence of a hidden plume rising within the core under the Arctic… ….Sudden Acceleration in the 1990s Observations from satellites, magnetic observatories, and field surveys show that the NMP drift speed suddenly increased in the 1990s [Newitt and Barton, 1996; Newitt et al., 2002], from 15 kilometers per year in 1990 to about 60 kilometers per year in 2002, after which it slowly decreased [Olsen and Mandea, 2007; Newitt et al., 2009]. This phenomenon was observed in both field survey measurements and global geomagnetic models (Figure 1a). It followed more than 150 years of slow drift at less than 15 kilometers per year, starting with the first location of the NMP by Ross. This sudden acceleration contrasts with the behavior of the south magnetic pole, which has a drift speed that has never exceeded 15 kilometers per year since the beginning of the twentieth century [Olsen and Mandea, 2007]

    http://eprints.whiterose.ac.uk/416/

    Is the geodynamo process intrinsically unstable?
    Recent palaeomagnetic studies suggest that excursions of the geomagnetic field, during which the intensity drops suddenly by a factor of 5 to 10 and the local direction changes dramatically, are more common than previously expected. The `normal’ state of the geomagnetic field, dominated by an axial dipole, seems to be interrupted every 30 to 100 kyr; it may not therefore be as stable as we thought.

    http://geosci.uchicago.edu/~rtp1/BardPapers/responseCourtillotEPSL07.pdf

    Response to Comment on “Are there connections between Earth’s magnetic field and climate?, Earth Planet. Sci. Lett., 253, 328–339, 2007” by Bard, E., and Delaygue, M., Earth Planet. Sci. Lett., in press, 2007
    Also, we wish to recall that evidence of a correlation between archeomagnetic jerks and cooling events (in a region extending from the eastern North Atlantic to the Middle East) now covers a period of 5 millenia and involves 10 events (see f.i. Figure 1 of Gallet and Genevey, 2007). The climatic record uses a combination of results from Bond et al (2001), history of Swiss glaciers (Holzhauser et al, 2005) and historical accounts reviewed by Le Roy Ladurie (2004). Recent high-resolution paleomagnetic records (e.g. Snowball and Sandgren, 2004; St-Onge et al., 2003) and global geomagnetic field modeling (Korte and Constable, 2006) support the idea that part of the centennial-scale fluctuations in 14C production may have been influenced by previously unmodeled rapid dipole field variations. In any case, the relationship between climate, the Sun and the geomagnetic field could be more complex than previously imagined. And the previous points allow the possibility for some connection between the geomagnetic field and climate over these time scales.

  18. FOR THOSE INTERESTED — W.F. Ruddiman is one of the ‘godfathers’ of the idea that humans have lengthened the present interglacial. He summarized, after publishing various aspects of the idea for almost 10 yrs, in his book, ‘Plows, Plagues and Petroleum – how humans took control of climate’, 2005 (Princeton University Press). The book was published about the same time as the above paper.

  19. ‘Jimbo says: (April 27, 2013 at 7:35 am)

    I vaguely recall that during the late Ordovician Co2 was over 4,000 parts per million. (Today 400ppm).

    I vaguely recall during the late Ordovician there was an ice age.

    I vaguely recall that Co2 remained at over 3,000 ppm throughout the glaciation.’

    Yes, yes, but that was NON-anthropogenic CO2!

  20. Is there a bit of schizophrenia among some readers at WUWT? Some seem to think that CO2 has NO warming influence, or too little to matter. Yes just a few posts ago, the scientist and skeptic Patrick Michaels reviewed a number of papers, including his own perspicacious 2002 study, which found that the climate sensitivity to CO2 is lower than forecast by models. Wonderful news, and for those of us who use data instead of model results to develop our opinions, expected news.

    But the earth is nevertheless warmed by CO2 (and black carbon, and methane, and tropospheric ozone, and cooled by sulfate from humans and from volcanos). It stands to reason that the “right” amount of CO2, at the right time, could keep us out of another ice age, given that CO2 lasts in the atmosphere for over a hundred years, once emitted. Make no mistake, based on the previous several interglacials, we are (or should be) headed down into another ice age.

    So the science question is, what is the “right” rate of emissions, not too cold, not too hot? When we get the models right, IF we ver get the models right, we will probably conclude that we want to slow down our CO2 emissions in this century (not come to a grinding and economically damaging halt), so that we will have CO2 to emit in the right quantities in future millennia. Obviously, this is a guesstimate. Don’t shoot me.

    Readers of WUWT should know that this is not the first paper to find that CO2 emissions from humans have kept the world warmer. William Ruddiman at U VA published a paper in 2003 saying that the deforestation of temperate areas where farming began, as humans cleared more land to grow crops, has very slowly made the earth warmer for 6000 years (the CO2 from decayed or burnt trees goes to the atmosphere, the crops don’t take up as much CO2 as the trees had stored).

    Here is a link for Ruddiman:

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

    Here is a link to his most well known paper (see Figs. 5, 6, and 9 especially, but the whole paper is worth your time):

    http://stephenschneider.stanford.edu/Publications/PDF_Papers/Ruddiman2003.pdf

  21. The effect CO2 as a Greenhouse gas becomes ever more marginal with greater concentration

    The political target of limiting the effect of Man-made global warming to only +2⁰C can never be attained. According to well understood physical parameters, the effectiveness of CO2 as a greenhouse gas diminishes logarithmically with increasing concentration and from the current level of ~390 ppmv, (parts per million by volume). Accordingly only ~5% of the effectiveness of CO2 as a greenhouse gas remains beyond the current level.

    This inconvenient fact is well understood in the climate science community. It can be accurately modeled using the Modtran program. The logarithmic diminution of the effect of CO2 is probably the reason why there was no runaway greenhouse warming from CO2 in earlier eons when CO2 levels were known to be at levels of several thousands ppmv.

    Remarkably, IPCC Published reports , (TAR3), do actually acknowledge that the effective temperature increase caused by growing concentrations of CO2 in the atmosphere radically diminishes with increasing concentrations. This information is in their report. It is well disguised for any lay reader, (Chapter 6. Radiative Forcing of Climate Change: section 6.3.4 Total Well-Mixed Greenhouse Gas Forcing Estimate).

    The diminishing percentage effectiveness of CO2 as a greenhouse gas as acknowledged by the IPCC and its concomitant diminishing temperature effect are as follows:
    increment cumulative
    0-100 ppmv: according to David Archibald / Modtran data ~2.22°C ~2.22°C
    100-200 ppmv: plants die below this level of CO2 +~0.29°C ~2.51°C
    200-300 ppmv: noted as the preindustrial CO2 level +~0.14°C ~2.65°C
    300-400 ppmv: current level IPCC attributes all as Man-made +~0.06°C ~2.71°C
    400-600 ppmv: business as usual till 2100 +~0.08°C ~2.79°C
    600-1000 ppmv: improving levels for plant growth +~0.06°C ~2.90°C

    Accounting for the diminution effect the actual temperature reductions achievable, the calculated values are in the range of few hundredths to a few thousandths of a degree Centigrade. As the margin of error for temperature measurements is about 1.0°C, these miniscule levels the temperature effects for all the efforts of those nations attempting to control their CO2 emissions, (only about 12% of world CO2 emissions), are marginal, immeasurable and thus irrelevant.

    Although the IPCC tacitly acknowledges that this crucial diminution effect with increasing concentrations effect exists, it certainly does not go out of its way to emphasise it. Like the Medieval Warm Period, that they attempted to eliminate with the Hockey Stick graph in 2001, the panel knows that wide public knowledge of the diminution effect with increasing CO2 concentration would be utterly detrimental to their primary message.
    “Man-made CO2 emissions are the cause of climate change”.

    The IPCC certainly does not explain these devastating consequences for the CAGW theory in their Summary for Policy Makers. This is because the IPCC is an essentially political organisation, that is solely tasked with the promotion and presentation of Man-made Climate Change from CO2 emissions, as an accepted and non-contentious fact for world’s politicians.
    Thus the IPCC is entirely misleading in its central claim for Policy Makers, as they say:

    “Warming of the climate system is unequivocal. Most of the observed increase in global average temperatures since the mid-20th century is very likely due to the observed increase in anthropogenic greenhouse gas concentrations.”

    Any unquestioning, policy maker is lead to assume that all increasing CO2 concentrations are progressively more harmful because of their escalating Greenhouse impact.

    But that is not so.

    From the present concentration of atmospheric CO2 at approaching 400 ppmv, only ~5% of the effectiveness of CO2 as a Greenhouse Gas remains.

    Increasing CO2 concentrations certainly do not have the ability to save the world from a coming Ice Age, at the end of the Holocene likely this millennium.

  22. Since the SST which regulates CO2 absorption, it is unlikely that the onset of the next ice age has anything to do with CO2 concentration.
    The earth may not see another ice age on schedule, unless there is regression in evolution of Greenland-Scotland ridge. However, if the G-S ridge has not opened sufficiently to prevent it at some time in future (further along the Milankovic cycle), than a degree of submarine engineering on the ridge could do the job as outlined here

  23. So the enormous hockey stick blade of Mann and Marcott must be greatly exaggerated (hyperbolic sarcasm). Do tell! Otherwise, we would have already prevented the next ice age. I think with climate sensitivity down to a third and dropping since the 2005 paper, we would need 3 times as much CO2 as stated IF CO2 INDEED CAN BE PROVEN TO BE AN IMPORTANT PLAYER AT ALL.

    Anyway, I can see where this is all going – refusing to let go of CO2 as the “control knob”, we are in for a few thousand years of papers in Nature, GRL, PNAS etc. calculating how CO2 is carrying us through what would otherwise be an ice age. “Try to debunk this Mr. McIntyre!” they will be able to say. They’ll be able to extend the hockey stick blade to be longer than the shaft in a graph subtracting the temperature of a deep glaciation – science will be dead.

  24. The true-believer syndrome merits study by science. What is it that compels a person, past all reason, to believe the unbelievable. How can an otherwise sane individual become so enamored of a fantasy, an imposture, that even after it’s exposed in the bright light of day he still clings to it–indeed, clings to it all the harder? –M. Lamar Keene

    http://skepdic.com/truebeliever.html

    It would seem that the AGW theory is ripe with folks who exhibit this malaise.

  25. shepherdfj says: April 27, 2013 at 7:03 am
    “I have read that the only way to get us out of the Ice Age, in which we currently live and have so lived for that last 2.5 million years, is to remove the Isthmus of Panama. CO2 does not come into play with this equation at all.”
    A more efficient way would be to block Drake’s Straigth. The Ice Age began when South America broke off from the Antarctic Peninsula, creating a circumpolar current, which made Antarctica a deep freeze.

  26. Given that the atmosphere contains roughly 750 gigatons of carbon, and that CO2 flux between the atmosphere and the earth/oceans is something on the order of 150 to 200 gigatons a year, where do these absurd statements about fossil fuel CO2 remaining in the atmosphere for thousands of years come from?

    More “models”? Are they counting only the specific molecules of CO2 (tagged somehow) that are produced by fossil fuel and not counting the rest of the normal flux? How do they get these numbers?

    Seems to me, as a first approximation, that 5 to 10 years would be more like it.

  27. Lubos Motl says:
    April 27, 2013 at 8:31 am
    ……….
    But this mistake is negligible relatively to the residence time. We will probably run out of – or stop using fossil fuels – within 300 years or much less.

    A point I keep banging on about. At around the end of the 18th century, or thereabouts, it was assumed London would, in some years ahead, be swamped by horse manure several storeys high. I am an optimist when it comes to human ingenuity. Assumptions are often the key ingredient in failed predictions. Just ask Malthusians or peak oilers.

  28. Here’s another geo-engineering project: Straighten up the Earth’s axial tilt by placing 2 mammoth nuclear-fueld jet turbines 180 degrees out of phase on top of very high lever towers – one at the north pole and the other at the south pole. Call it project Archimedes.

  29. Not only can co2 prevent another ice age it can also cause Northern Hemisphere ice sheets to GROW! Oh noes! / sarc

    Abstract
    Will greenhouse warming lead to Northern Hemisphere ice-sheet growth?

    ALTHOUGH model simulations predict a higher mean global temperature by the middle of the next century in response to increased atmospheric concentrations of greenhouse gases1, the response of the cryosphere to specific changes in latitudinal and seasonal temperature distribution is poorly constrained by modelling2,3 or through instrumental measurements of recent variations in snow cover4and ice thickness5,6. Here we examine the recent geological record (130 kyr to present) to obtain an independent assessment of ice-sheet response to climate change. The age and distribution of glacial sediments, coupled with marine and terrestrial proxy records of climate, support arguments that initial ice-sheet growth at the beginning of the last glacial cycle occurred at high northern latitudes (65–80° N) under climate conditions rather similar to present. In particular, the conditions most favourable for glacier inception are warm high-latitude oceans, low terrestrial summer temperature and elevated winter temperature. We find that the geological data support the idea that greenhouse warming, which is expected to be most pronounced in the Arctic and in the winter months, coupled with decreasing summer insolation7 may lead to more snow deposition than melting at high northern latitudes8 and thus to ice-sheet growth.

  30. Ed Zuiderwijk says: (April 27, 2013 at 8:52 am)

    “No, it will not. CO2 is not a climate driver.”

    Exactly. CO2 follows warming; it doesn’t cause it.
    With the evidence for little, no or even slightly negative feedback from clouds and watervapor, any level of CO2 and any change of it will have little or no impact on climate. Case closed imho.

    Climate is driven by the sun, the oceans, cosmic rays, clouds and watervapor. CO2 has nothing to do with it..

  31. Jimbo says

    …and thus to ice-sheet growth.

    henry says

    global cooling will result in more arctic ice,

    http://blogs.24.com/henryp/2012/10/02/best-sine-wave-fit-for-the-drop-in-global-maximum-temperatures/

    count 88 years back, where are we?

    http://wattsupwiththat.com/2008/03/16/you-ask-i-provide-november-2nd-1922-arctic-ocean-getting-warm-seals-vanish-and-icebergs-melt/

    sounds familiar with recent reports?
    remember by 1950 all had frozen back.

    we will see the same again by 2040

    but will man be ready for the coming cold?

  32. scarface says
    Climate is driven by the sun, the oceans, cosmic rays, clouds and watervapor. CO2 has nothing to do with it..
    henry says
    true
    how do we get that msg out to the whole world?

  33. I almost wish I had stayed in academia, but it probably would have made me a bad person.

    I quote the philosopher Ray Stantz: “Personally, I liked the university. They gave us money and facilities; we didn’t have to produce anything! You’ve never been out of college. I’ve worked in the private sector. They expect results!”

    Seriously, *basic* inconsistencies remain unresolved and the general response seems to be “shrug and move on.”

  34. Nothing can stop the next ice age.. All we can do is migrate to the equator.. Luckily sea levels will be way down and we have the technology to live on and under the ocean..

    What worries me more is now fast it will happen.. Its not like we can pick up and move nuclear reactors or storage, not to mention toxic chemicals or cities or garbage dumps.. The leading edge of the glaciers will be the largest imaginable toxic radio active dump, that will be next to impossible to contain..

    When the melt comes this will run off into our smaller oceans..

    Imagine the northern hemisphere scraped clean and ground up, running off into our oceans in a short period of time.. A ten year melt will pretty much deal with the leading edge and release it all..

    IMHO a true environmental disaster that our oceans may not be able to handle..

  35. I have just taken my Playtex 24hr girdle off, if I start laughing now…well it will just get ugly!

  36. Wow! To think that me and my BBQ are holding back the miles of ice that should be crushing New York and with it Jim Hansen’s office under miles of grinding ice.

    I am awesome!

  37. ferdberple says (April 27, 2013 at 7:35 am): “Otherwise, we are left with the 1950′s alternative. Building thousands of nuclear power plants to heat the oceans, and/or thousands of gigantic solar reflectors in space to warm the land.”

    Or dusting the ice & snow with black carbon…

  38. pCO2 is the negatve log (10) of the CO2 concentration in water in moles per liter
    ppm ((=mg per kg) is not the right dimension for this

  39. According to Berger and Loutre 2002, the next Ice age is not due until 50.000 years from now.

    An Exceptionally Long Interglacial Ahead?

    A. Berger and M. F. Loutre

    Today’s comparatively warm climate has been the exception more than the rule during the last 500,000 years or more. If recent warm periods (or interglacials) are a guide, then we may soon slip into another glacial period. But Berger and Loutre argue in their Perspective that with or without human perturbations, the current warm climate may last another 50,000 years. The reason is a minimum in the eccentricity of Earth’s orbit around the Sun.

    Science 23 August 2002:
    Vol. 297. no. 5585, pp. 1287 – 1288
    DOI: 10.1126/science.1076120

    ftp://ftp.soest.hawaii.edu/engels/Stanley/Textbook_update/Science_297/Berger-02.pdf

  40. Earth: 26% clouds, 0.65 cloud albedo, 341.5 W/m2 TOA TSI: 57.7 W/m2 reflection. 15 W/m2 increase in cloud reflection , is 32.8% cloud cover Earth.

    What would that take?

  41. A strange rehash of Berger and Loutre(2003). “An Exceptionally Long Interglacial Ahead”- Science. Also, the resolution in Fig 3 does not show the proper decline in June insolation at 65N
    over the next few thousands of years.

  42. C’mon folks, this is a trap. Our dear David Archer is a true believer in CAGW. It only takes a couple moments to google this ‘clever’ professor’s name. He’s such a twit he actually believes that we’re at a tipping point of, sinister drum beat please, no return. Our weekend frolic with industrialization turned into a weekend of sheer, pee in the pants, terror. You know the rest. In fact, our bearded (in which case I’ve got them all beat) professor seems to occupy a place at Real Climate. Now, I don’t wish to get down on the University of Chicago (since most of the virtual army of doctors I see practice there) but our current frowning POTUS, Mr. Barack Obama was one of the visiting, wink, wink, scholars there and Mr. Archer still comfortably resides there. Make no mistake, he’s quite familiar with the ‘Chicago Way.’ If anybody believes his paper, and he’s hoping skeptics will, he’ll do a switharoo.

  43. Ray
    “Not having mile thick ice sheets crush northern hemisphere cities is a good thing, don’t you think?”

    Think of all the shoveling we would save…

    We could do some strategic shovelling in order to improve the lives of hundreds of millions. Give Washington (DC) and Brussels a miss perhaps?

  44. From NASA Earth Fact Sheet Mass of atmosphere ~ 5.1 * 10^18 kg

    The EIA shows CO2 emissions from energy use from 1980 through 2011 as 753,896.0782 million metric tons.

    The Mona Loa CO2 measurements are
    2011 391.62 ppm
    1980 338.68 ppm

    This is a change of 52.94 ppm

    Using the 5.1 * 10^18 kg for atmosphere we get an increase of 2.7 * 10^14 kg of CO2.

    This is 270,000 million metric tons, but we emitted 753,896 million metric tons.

    That leaves 483,896 million metric tons or about 64% that must have gone somewhere.

    The models call for

    “The equilibrium partitioning of a slug of new CO2
    between the atmosphere and the CaCO3-buffered
    oceans is such that, in the absence of natural CO2
    forcing such as glacial inception, approximately
    7% of the CO2 remains in the atmosphere 100 kyr
    after the perturbation,…”.

    If the process is linear, this would be a time constant of about 37,000 years, so in the 31 years,
    assuming that it had all been dumped in in 1980, we should have had about 621 million metric tons taken up in the by the modeled process. This leaves about 483,275 million metric tons which went somewhere.

    It would take some very persuasive arguments in a fairly concise form before I would consider it worthwhile to look closely at their models for the lifetime of atmospheric CO2.

    Donald Mitchell

  45. Henry@donald
    I know where the missing 60% went

    namely

    everyone wants more trees, more lawns

    they also want more wine, more crops,

    and then God decided to give it to them

    and He makes it from water and CO2……

    mostly..

    God bless you all here!

  46. “If Humanity can Geo-engineer so readily, Why not turn Mars into Hawaii.
    The hubris, it burns.”

    For all those people rabbiting on about how close we are to terraforming other worlds, I ask why not turn the rest of Earth into Hawaii? Forget Mars! I say, “Earth First!”

  47. It’s doubtful that CO2 has enough influence to stop an ice age but the ready availability of fossil fuels and nuclear power may well help the human race survive it.

  48. John says:
    April 27, 2013 at 8:54 am
    …………..
    But the earth is nevertheless warmed by CO2 (and black carbon, and methane, and tropospheric ozone, and cooled by sulfate from humans and from volcanos). It stands to reason that the “right” amount of CO2, at the right time, could keep us out of another ice age, given that CO2 lasts in the atmosphere for over a hundred years, once emitted. Make no mistake, based on the previous several interglacials, we are (or should be) headed down into another ice age.

    Just 2 points:
    1) Did you forget water vapour? The most powerful greenhouse gas.

    2) “It stands to reason that the “right” amount of CO2, at the right time, could keep us out of another ice age….”

    Oh really! Click here and look at the later half of the Cretaceous and start of the Tertiary.

  49. It would be wonderful if it were true, but,

    RGB@Duke eloquently reminded us some time ago, that we entered a glaciation during the Ordovician period when co2 was at 7000 ppm and that glaciation continued through much of the Silurian period when co2 never dropped below 4000 ppm.

    Clearly co2 plays no part in preventing glaciations. The authors haven’t done their homework.

  50. Douglas Proctor said “Earth: 26% clouds, ~ 15 W/m2 increase in cloud reflection , is 32.8% cloud cover Earth.”

    What would that take?

    I reckon Jasper Kirkby and or Svensmark might well have a good idea about the answer. Perhaps an examination of Livingston & Penn (& recently Svalgaard) might also lead to some conclusions.

  51. And even IF
    (just for the sake of argument) CO2 could prevent glaciations, the amount of CO2 emitted by NON-human sources would still be FAR AND AWAY the controlling causation of any (just for the sake of argument) warming.

    [Just a non-scientist wanting to reinforce the politically (and given that people are dying due to fantasy science policies), VITALLY) essential fact that HUMANS CAN DO NOTHING ABOUT the EFFECTIVE level of CO2 in the atmosphere.]

  52. William Astley says:
    April 27, 2013 at 8:32 am
    “There are burn marks on the surface of the planet that correlate with Younger Dryas abrupt cooling period (the duration of the Younger Dryas cooling event is roughly 1000 years). There are burn marks on the planet’s surface that correlate with other geomagnetic excursions.

    This bit is tucked in between “a restart of the solar magnetic cycle after it has been interrupted” and “massive discharge from the sun”, such that one might get the idea that something has been scorched by the Sun. Either that or there has been something left out while doing a hurried cut and paste construction.

    The Carolina Bays . . .

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

    . . . have been cited as “burn marks” although these seem explainable by known terrestrial processes. So, if such as these are what you mean by “burn marks”, perhaps you can explain what did cause them. If you have some other set of features in mind – what are they?

  53. We are still at the mercy of the sun, super volcanoes, meteors, cosmic radiation from super novas and some event we do not know of yet.

  54. William Astley says:

    April 27, 2013 at 8:32 am
    ===================================
    Bravo!
    Milankovitch holds but one seat on the glacial/interglacial board of directors and Carbon dioxide is a minor stockholder.

    As we congratulate ourselves with our 75% correlation understanding of the twitters of glacial/interglacial oscillations, we must remember that behind this looms the task of explaining why the last session of tweets ended in the early Permian about 250 million years ago, and the entire interval from then to the Pleistocene, including many orbital cycles, and including the “nuclear winter” of the Club Med impact, was much warmer than today with no ice sheets to recede or advance.

  55. If I remember well, according to models based on radiative forcing, the cooling after Younger dryas did not happen. It is present in the ice core record, but according to the models it did not happen, since radiative forcing in computer model says it could not happen.

  56. Canman says:
    April 27, 2013 at 7:18 am
    In his book, “Coal Trains of Death” Hansen says that the output from a single chlorofluorocarbon plant is enough to prevent an ice age.

    Would that be before or after the oceans boil?

    :)

  57. The term pCO2 is more commonly used as the partial pressure of CO2 in a gas or liquid, and its units are pressure units, eg mm Hg.

  58. Not having mile thick ice sheets crush northern hemisphere cities is a good thing, don’t you think?

    Depends on the city. Some festering pits of pestilence are best covered over and left to decompose for a very long time, like with landfills, you know? ;)

  59. I am looking forward to the next ice age, as it will wipe out all the idiotic progressives. While I too will suffer the same fate, I recall Kennedy’s sage advice: “ask not what your country can do for you…”

  60. This, of course, was Bert Bolin’s original hypothesis way back in 1959 when he was an obscure scientist. Then it was good news when interviewed for a BBC program “The Weather Machine”. Later he saw all the money and influence he could get (and did get) by pretending it was bad news.

  61. Uh huh, its another paper that missed April 1.
    I think the have the sign inverted,man caused co2 actually causes cooling, the last 15years provide IPCC certainty and we must cut emissions or we will all freeze here after.

  62. Jimbo says:
    April 27, 2013 at 1:03 pm

    ” John says:
    April 27, 2013 at 8:54 am
    …………..
    “But the earth is nevertheless warmed by CO2…It stands to reason that the “right” amount of CO2, at the right time, could keep us out of another ice age….”

    Oh really! Click here and look at the later half of the Cretaceous and start of the Tertiary.”

    Jimbo, from your link I note that the global temp curve maxes out at ~25C. This is rather high in terms of global T even though it is still below Willis’s Thermostat Limit of 30 for the ocean temp. Also, although there is a very general correlation with the widest swings in CO2 levels, levels between 1000-7000ppm appear to support this 25 C suggesting not a strong correlation.

  63. Here is a nice zoom-in of the Milankovitch Cycles (mid-June solar insolation at 65N) from David Archibald (derived from Loutre and Berger, 2000).

    Generally, in looking back at all the ice ages in the last 1.0 million years (which is when the length of the ice ages switched to about 100,000 years), it appears to me that this value needs to drop below about 470-465 W/m2 to kick us into an ice age. After that initial drop, a lot of ice volume builds up and it takes two or three good up-swings to break the back of glaciers to put us back into an interglacial (essentially Gerald Roe’s ice volume model which is really the only explanation that seems to work ).

    The June solar insolation forecast for 65N is that we are not going to get into that 465 W/m2 range until 55,000 years from now (or more likely 125,000 years from now).

    It really comes down to, is the summer sun warm enough to melt all the winter snow at lower altitudes (and melt some of the Arctic sea ice in September) at 75N (which is a more accurate latitude than 65N. 75N is where all the action is.

    If the snow and ice melts at 75N in the summer, there is no ice age and no glaciers build up on Ellesmere Island, Baffin island and northern Greenland kicking us into an ice-Albedo feedback loop that puts glaciers in Chicago.

    Over the next 2,000 years, solar insolation at 65N declines by about 0.5 W/m2 (a tiny, tiny amount) and the Arctic sea ice and the snow on Ellesmere Island will continue melting in the summer.

    We’re stuck in the interglacial which will likely be the longest one since the ice ages started 2.6 million years ago. The Milankovitch Cycles are not as regular as many people believe.

    http://wattsupwiththat.com/2009/02/23/ice-ages-and-sea-level/

  64. From Sean on April 27, 2013 at 2:12 pm:

    I am looking forward to the next ice age, as it will wipe out all the idiotic progressives.

    Nah. As always happens with these infestations, there’s an elite class of smart “progressives” who are in control of the lesser ones, positioned to take advantage regardless. The idiotic progressives are like worker bees, generated by the queen bees as needed, although new queens can be “adopted” by and take over other worker bees like after an old queen dies or has a sex scandal with the wrong species. The “idiotic” group lives and dies for the benefit of the hive, while not realizing the hive exists for the benefit of the queen, who would be nothing without it.

    The smart ones are rich enough to migrate where needed, towards poles or equator. They’ll make more idiotic progressives when they get there.

    While I too will suffer the same fate…

    Wow, you’re expecting a really long life.

    …I recall Kennedy’s sage advice: “ask not what your country can do for you…”

    That was superseded by the Obama Indoctrine: Ask not what your country is doing to you, ask how you can let your country do you even more.

  65. Mitchell @9:27:
    Nicc calc. 64% “missing”? Consider this: never was produced. A negative Trenberth Event. All eco-green activist use top-end estimates, all governments exaggerate industrial activity for ego and green policies and future claims of reduction. Compounding error:eco.green then say government lies to prevent need for action, say situation worse than stated. Trouble is, observations then show Earth more resilient than modeled, mitigation without regulation sufficient.

    Initial exaggeration drives scare, later refutes models. Like the BP Gulf Coast oil spill. I say way less oil spilled than claimed, reason couldn’t find oil plume or mess on seafloor later. But high volume resource estimates benefit company, environ-activsts and government. Also competitors who want oil leases on-trend.

    ALL climate change data that is a calculation and not a direct measurement should be viewed suspiciously. Ask, who benefits from the benefit-of-doubt going one way or the other.

    Graph CO2 global production per year vs CO2 ppm.

    Ain’t that interesting: bio-processes, ocean absorption or exaggerated data?

  66. “The Carboniferous Period and the Ordovician Period were the only geological periods during the Paleozoic Era when global temperatures were as low as they are today. To the consternation of global warming proponents, the Late Ordovician Period was also an Ice Age while at the same time CO2 concentrations then were nearly 12 times higher than today– 4400 ppm. According to greenhouse theory, Earth should have been exceedingly hot. Instead, global temperatures were no warmer than today. Clearly, other factors besides atmospheric carbon influence earth temperatures and global warming.”

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

    Indeed – politics and climate models?

  67. Bill Illis says:
    April 27, 2013 at 3:21 pm

    Tzedakis appears to believe that Milankovitch orbital phase takes precedence over insolation magnitude. Note the text in bold in the abstract below.

    Thus it may be within 1500 years, not 55,000 years, that glacial inception occurs.

    Determining the natural length of the current interglacial

    P. C. Tzedakis, J. E. T. Channell, D. A. Hodell, H. F. Kleiven & L. C. Skinner
    Nature Geoscience (2012) doi:10.1038/ngeo1358
    Received 23 May 2011 Accepted 28 November 2011 Published online 09 January 2012 Corrected online 10 January 2012, corrected by WUWT 28 April 2013.

    The current orbital configuration is characterized by a weak minimum in summer insolation. However, the timing of the hypothetical next glaciation remain unclear. Past interglacials can be used to draw analogies with the present, provided their duration is known. Here we propose that the minimum age of a glacial inception is constrained by the onset of bipolar-seesaw climate variability, which requires ice-sheets large enough to produce iceberg discharges that disrupt the ocean circulation. We identify the bipolar seesaw in ice-core and North Atlantic marine records by the appearance of a distinct phasing of interhemispheric climate and hydrographic changes and ice-rafted debris. The glacial inception during Marine Isotope sub-Stage 19c, a close analogue for the present interglacial, occurred near the summer insolation minimum, suggesting that the interglacial was not prolonged by subdued radiative forcing. Assuming that ice growth mainly responds to insolation, this analogy suggests that the end of the current interglacial will occur within the next 1500 years.

    [Note - some irrelevant discussion on trace gasses was removed from the text to clarify the text.]

  68. To everyone on this site who thinks that CO2 has zero or almost no effect on warming the planet — riddle me this:

    Why is it that people like Patrick Michaels get such cheers (as they should) when they do the science better and find out that the actual CO2 sensitivity is about 2 degrees C for a doubling of CO2, using actual temperature records in many of those studies? What is good about this is that the IPCC mean temperature increase for a doubling of CO2 is about 80% too high, and a crisis isn’t nigh. In other words, the IPCC is part of trying to panic people into thinking that if we don’t completely stop emitting CO2, right now, all sorts of bad things will happen. Thanks to Michaels and others, almost all of them featured on WUWT at some time (e.g., Schmittner et al), we now have good evidence that the IPCC, like Michael Mann, has been playing games (in fact, Mann hid the decline while a lead author for the IPCC).

    But the message is also that CO2 does in fact cause warming, about 2 degrees C, more or less, from a doubling.

    And no, I didn’t forget that water vapor is a powerful greenhouse gas.

    The issue is what happens when you double CO2, INCLUDING reducing the high feedbacks that the IPCC assumed from water vapor. That answer, according to Michaels and the several new studies he cites, is about 2 degrees C, plus or minus:

    http://wattsupwiththat.com/2013/04/25/a-compilation-of-lower-climate-sensitivities-plus-a-new-one/

    Skeptics: they look at reality, at what temperatures have done the last 15 years, and say the IPCC and Michael Mann are feeding us BS, and that doubling of CO2 won’t get nearly the increase in temperatures that are claimed by the IPCC and Mann.

    Deniers: they ignore the huge amount of science that says that, yes, CO2 does increase temperature, and say that doubling CO2 in the atmosphere won’t affect temperatures, or will do so hardly at all.

    I’m on the side of the scientific skeptics, like Michaels. Just because Mann and the IPCC feed us BS doesn’t mean that we can believe whatever we want — we still must be true to what the science actually says, when the process works out and we get more reliable answers. And then the policies that follow must be based on the new, better science, not what the IPCC and their PR teams want us to do.

  69. phlogiston says:
    April 27, 2013 at 4:01 pm
    —————

    I’m not sure how they were calculating a bi-polar see-saw, but they did use Lisiecki and Raymo (2005) to come up with this. The authors improved on the dating from their 2005 paper with (LR 2009) for the north Atlantic and north Pacific.

    This might be the first time this is shown but the correlation between Antarctica and the north Atlantic over the last 800,000 years is scary close. They are both moving almost exactly the same.

  70. shepherdfj is correct. It is the Isthmus of Panama that is the cause of the Pleistocene era, and only its removal, allowing warmer waters from the Pacific to mix with the Atlantic, will prevent this from recurring again and again.

    Only the action above, and halting Impactors from causing immediate sudden drops in temperature, will allow the planet to go back to a more stable climate scenario.

  71. shepherdfj is correct. It is the Isthmus of Panama that is the cause of the Pleistocene era, and only its removal, allowing warmer waters from the Pacific to mix with the Atlantic, will prevent this from recurring again and again.

    Only the action above, and halting Impactors from causing immediate sudden drops in temperature, will allow the planet to go back to a more stable climate scenario.

  72. What is readily apparent from this post and many of the comments that follow is that we are nowhere near understanding what triggers glacials and interglacials. What is more, we are unlikely to achieve a full understanding for millenia, if ever. While the summer insolation at 65N may be the current favourite explanation, it can neither be proved or disproved, just like all the other theories expounded or linked to in comments.

  73. “Not having mile thick ice sheets crush northern hemisphere cities is a good thing, don’t you think?”

    The mile-thick ice sheets are part of the natural rhythm of life. Why do you hate the Earth so much?

  74. It is the Isthmus of Panama that is the cause of the Pleistocene era
    =================================================
    One tries to be tolerant, but this is just plain ignorant. Puleeese, check out the reconstructions of Scotese or Blakely. Even at the PETM, about 48 million years before the Pleistocene, there was a very significant island arc and continental shelves blocking the Isthmus on Panama. the most that can be imagined even then is an “Atlantic Warm Pool” at the restriction.

    It is crystal clear from continental reconstructions that Ice Ages, meaning extended periods with multiple glacial/interglacial cycles, are not about continental drift. There have only been a few of them in the last 600 million years and they have occurred in a wide variety of continental configurations, none of them, except the current, like today.

  75. Jimbo, I didn’t say that we will have any problem in 100 or 200 or 300 years. Quite on the contrary. I agree with your comment – and with Crichton’s comments on manure in New York – as much as you do. But I said that the fossil fuels won’t be our main source of energy because of a combination of the natural (not requiring any subsidies!) research of the alternatives and the increasing price of the fossil fuels whose easily accessible volume is limited (the limit depends on how we define “easily”) and that will require more complicated technologies to be obtained – not just fracking which may be OK for 150 years.

  76. Not bad trick for a trace gas. So it really is responsible for global not-cooling – a very normal cyclic event – at the same time it is responsible for global warming – another expected event following a cold period. The alarmists are right – we’re going to be warm (and comfortable though they don’t make this claim) for centuries. Meanwhile I’m still wearing a wool shirt every day outside because it is freezing cold. I’m going to go light my burn barrel and hustle this warming along.

  77. John:

    Nice try at damage limitation in your post at April 27, 2013 at 4:51 pm.
    But it is a total fail.

    Climate sensitivity is so low that any effect of increased CO2 will be much too small for it to be detectable because natural climate variability is much, much greater.

    Empirical measurements (n.b. NOT model-derived estimates) show climate sensitivity is much lower than you claim (i.e.you claim 2°C for a doubling of the air’s CO2 content).

    Climate sensitivity is only ~0.4°C for a doubling of the air’s CO2 content equivalent.
    This is indicated by the independent studies of
    Idso from surface measurements

    http://www.warwickhughes.com/papers/Idso_CR_1998.pdf

    and Lindzen & Choi from ERBE satelite data

    http://www.drroyspencer.com/Lindzen-and-Choi-GRL-2009.pdf

    and Gregory from balloon radiosonde data

    http://www.friendsofscience.org/assets/documents/OLR&NGF_June2011.pdf

    Richard

  78. Total rubbish. Present atmospheric CO2 levels are not high but low compared to the past. No amount of CO2 will prevent an ice age—- 8000ppmv did not prevent a severe ice age during the Ordovicean.

  79. When the next ice age finally hits, I’m sure somehow CO2 will be blamed for the cooling and taxing it will fix everything.

  80. Milankovitch cycle Theory Problems:
    The last interglacial the Eemian ended abruptly. There is no physical explanation as to why the Eemian interglacial ended abruptly. A paper that tells us this current interglacial will last 400,000 years needs to explain why the last interglacial ended abruptly and to provide an answer to the following paradoxes (observations which can be explained by the theory and appear to contradict theory) which support the assertion that insolation at 65N does not cause the glacial/interglacial cycle.

    1) How does one explain the observation that the glacial/interglacial cycles started with a cycle periodicity of 41,000 years in duration and then 1.6 millions ago the cycle time changed to a cycle of 100,000 years (90,000 years glacial and 10,000 years interglacial.)
    2) Orbital eccentricity is the weakest of the orbital cycle modulation on insolation. Why does it dominate for the last 1.6 million years?
    3) The stage 5 glacial was terminated 10,000 years before the insolation change. There is no cause for that change. There is no back up forcing mechanism to terminate glacial periods.
    4) There is evidence in the paleo climate data of cyclic abrupt climate change. (Heinrich events, such as the 12,900 years BP Younger Dryas abrupt cooling event.) There is no forcing mechanism that explains the cyclic abrupt climate changes.
    5) The majority of the glacial and interglacial periods have ended abruptly. The paleo record supports the assertion that there is a mysterious cyclic abrupt climate forcing function that terminates both the glacial and interglacial period. (Heinrich event)
    6) The cycle abrupt climate change cools both the Southern Hemisphere and the Northern hemisphere synchronously. This does not make sense as the Southern Hemisphere was at maximum insolation in the summer when the Northern Hemisphere has at minimum insolation in the summer and vice verse.

    http://www.esd.ornl.gov/projects/qen/transit.html

    Sudden climate transitions during the Quaternary
    The time span of the past few million years has been punctuated by many rapid climate transitions, most of them on time scales of centuries to decades or even less. The most detailed information is available for the Younger Dryas-to-Holocene stepwise change around 11,500 years ago, which seems to have occurred over a few decades. The speed of this change is probably representative of similar but less well-studied climate transitions during the last few hundred thousand years. These include sudden cold events (Heinrich events/stadials), warm events (Interstadials) and the beginning and ending of long warm phases, such as the Eemian interglacial. Detailed analysis of terrestrial and marine records of climate change will, however, be necessary before we can say confidently on what timescale these events occurred; they almost certainly did not take longer than a few centuries.
    Various mechanisms, involving changes in ocean circulation, changes in atmospheric concentrations of greenhouse gases or haze particles, and changes in snow and ice cover, have been invoked to explain these sudden regional and global transitions. We do not know whether such changes could occur in the near future as a result of human effects on climate. Phenomena such as the Younger Dryas and Heinrich events might only occur in a ‘glacial’ world with much larger ice sheets and more extensive sea ice cover. However, a major sudden cold event did probably occur under global climate conditions similar to those of the present, during the Eemian interglacial, around 122,000 years ago. Less intensive, but significant rapid climate changes also occurred during the present (Holocene) interglacial, with cold and dry phases occurring on a 1500-year cycle, and with climate transitions on a decade-to-century timescale. In the past few centuries, smaller transitions (such as the ending of the Little Ice Age at about 1650 AD) probably occurred over only a few decades at most. All the evidence indicates that most long-term climate change occurs in sudden jumps rather than incremental changes. …. …..According to the marine records, the Eemian interglacial ended with a rapid cooling event about 110,000 years ago (e.g., Imbrie et al., 1984; Martinson et al., 1987), which also shows up in ice cores and pollen records from across Eurasia. From a relatively high resolution core in the North Atlantic. Adkins et al. (1997) suggested that the final cooling event took less than 400 years, and it might have been much more rapid. …. …..The event at 8200 ka is the most striking sudden cooling event during the Holocene, giving widespread cool, dry conditions lasting perhaps 200 years before a rapid return to climates warmer and generally moister than the present. This event is clearly detectable in the Greenland ice cores, where the cooling seems to have been about half-way as severe as the Younger Dryas-to-Holocene difference (Alley et al., 1997; Mayewski et al., 1997). No detailed assessment of the speed of change involved seems to have been made within the literature (though it should be possible to make such assessments from the ice core record), but the short duration of these events at least suggests changes that took only a few decades or less to occur. …. ….The Younger Dryas cold event at about 12,900-11,500 years ago seems to have had the general features of a Heinrich Event, and may in fact be regarded as the most recent of these (Severinghaus et al. 1998). The sudden onset and ending of the Younger Dryas has been studied in particular detail in the ice core and sediment records on land and in the sea (e.g., Bjoerck et al., 1996), and it might be representative of other Heinrich events.

    http://upload.wikimedia.org/wikipedia/commons/f/f7/Five_Myr_Climate_Change.svg

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

    http://www.seas.harvard.edu/climate/pdf/wunsch_2004.pdf

    Quantitative estimate of the Milankovitch-forced contribution to observed Quaternary climate change by Carl Wunsch
    A number of records commonly described as showing control of climate change by Milankovitch insolation forcing are reexamined. The fraction of the record variance attributable to orbital changes never exceeds 20%. In no case, including a tuned core, do these forcing bands explain the overall behavior of the records. At zero order, all records are consistent with stochastic models of varying complexity with a small superimposed Milankovitch response, mainly in the obliquity band. Evidence cited to support the hypothesis that the 100 Ka glacial/interglacial cycles are controlled by the quasi-periodic insolation forcing is likely indistinguishable from chance, given the small sample size and near-integer ratios of 100 Ka to the precessional periods. At the least, the stochastic background‘‘noise’’ is likely to be of importance.

    http://www.agu.org/pubs/sample_articles/cr/2002PA000791/2002PA000791.pdf

    The 41 kyr world: Milankovitch’s other unsolved mystery

    Milankovitch cycle Theory Problems:
    1) 100,000-year problem
    The 100,000-year problem is that the eccentricity variations have a significantly smaller impact on solar forcing than precession or obliquity and hence might be expected to produce the weakest effects. The greatest observed response is at the 100,000-year timescale, while the theoretical forcing is smaller at this scale, in regard to the ice ages. …
    2) 400,000-year problem
    The 400,000-year problem is that the eccentricity variations have a strong 400,000-year cycle. That cycle is only clearly present in climate records older than the last million years. If the 100ka variations are having such a strong effect, the 400ka variations might also be expected to be apparent. This is also known as the stage 11 problem, after the interglacial in marine isotopic stage 11 that would be unexpected, if the 400,000-year cycle has an impact on climate. ….
    3) Stage 5 problem
    The stage 5 problem refers to the timing of the penultimate interglacial (in marine isotopic stage 5) that appears to have begun ten thousand years in advance of the solar forcing hypothesized to have caused it (the causality problem).
    4) Effect exceeds cause
    420,000 years of ice core data from Vostok, Antarctica research station.
    The effects of these variations are primarily believed to be due to variations in the intensity of solar radiation upon various parts of the globe. Observations show climate behavior is much more intense than the calculated variations. Various internal characteristics of climate systems are believed to be sensitive to the insolation changes, causing amplification (positive feedback) and damping responses (negative feedback).
    5) The unsplit peak problem
    The unsplit peak problem refers to the fact that eccentricity has cleanly resolved variations at both the 95 and 125ka periods. A sufficiently long, well-dated record of climate change should be able to resolve both frequencies,[15] but some researchers interpret climate records of the last million years as showing only a single spectral peak at 100ka periodicity. It is debatable whether the quality of existing data ought to be sufficient to resolve both frequencies over the last million years.
    6) The transition problem
    Variations of Cycle Times, curves determined from ocean sediments
    The transition problem refers to the switch in the frequency of climate variations 1 million years ago. From 1–3 million years, climate had a dominant mode matching the 41ka cycle in obliquity. After 1 million years ago, this switched to a 100ka variation matching eccentricity, for which no reason has been established.
    7) Identifying dominant factor
    Milankovitch believed that decreased summer insolation in northern high latitudes was the dominant factor leading to glaciation, which led him to (incorrectly) deduce an approximate 41ka period for ice ages.[16] Subsequent research has shown that the 100ka eccentricity cycle is more important, resulting in 100,000-year ice age cycles of the Quaternary glaciation over the last million years.

  81. If they made the model interfaces easier to use, then they wouldn’t have to write all these papers. Simple blog posts of input settings and screenshots of cool results wold suffice.

  82. Bill Illis says:
    April 27, 2013 at 5:27 pm
    phlogiston says:
    April 27, 2013 at 4:01 pm
    —————

    I’m not sure how they were calculating a bi-polar see-saw, but they did use Lisiecki and Raymo (2005) to come up with this. The authors improved on the dating from their 2005 paper with (LR 2009) for the north Atlantic and north Pacific.

    This might be the first time this is shown but the correlation between Antarctica and the north Atlantic over the last 800,000 years is scary close. They are both moving almost exactly the same.

    http://s14.postimg.org/gqap88co1/Last_800_K_NAtl_Antarctica_Temps.png

    That graph looks like a pretty damn good mutual validation of both the N Atlantic dO18 and the Antarctic Epica Dome C core temperature reconstructions.

  83. I am a lukewarmer on the CO2 issue. Whether the temp effect of a CO2 doubling is +1 or +3 degrees C, it is a move in the right direction. Humanity WILL BE devastated by the eventual cooling trend as we slip into the next glacial epoch.

  84. So rising CO2 levels will postpone/prevent the (overdue) onset of a cyclical Pleistocene Ice Age? Cher ami, mi amigo– are you plain nuts, or just plain schtoopid?

  85. William Astley says:
    April 28, 2013 at 6:18 am
    Milankovitch cycle Theory Problems:
    The last interglacial the Eemian ended abruptly. There is no physical explanation as to why the Eemian interglacial ended abruptly.
    ————

    Summer solar insolation at 65N fell from 540 W/m2 at 127Kya to 430 W/m2 by 114Kya.

    That is really just about the maximum swing that there can be in such a short period of time (its the Max).

    By the low point at 114 Kya, temps had already dropped by 6.0C in Antarctica and up to 11.0C in Greenland.

    The last ice age had already begun and the Ice-Albedo feedback more than offset the bounce-back in summer solar insolation which occurred after 114Kya. More Sun had no effect because the ice reflects between 50% to 80% of it back to space versus interglacial conditions which are 15% to 65% in the summer at this location.

    A few more downswings and few more upswings and the glaciers are in Chicago (where they have no business being because the Sun is 1.75 times strong enough to melt all the ice and snow – even in the low points of Milankovitch). It is the sunlight reflecting nature of the glaciers and the snow on the glaciers which is the big make-or-break factor.

    One good downswing (or especially the maximum one) is enough to kick off the feedback loop (and it can end just as suddenly when the feedback loop goes the other way because the Sun in Chicago in the Summer and even at 65N is more than strong enough to melt all the ice and snow. Its the Albedo which makes the difference.

Comments are closed.