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How close are we to catastrophic climate change?

The views expressed are those of the author and are not necessarily those of Scientific American.


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As you may have noticed, scientists remain convinced that humans are altering the global climate with an excess of greenhouse gas emissions—soot, methane and the ever-present carbon dioxide we pump out from our lungs and coal-burning power plants. The question is: how bad is said climate change going to get?

After all, concentrations in the atmosphere are going up by roughly two parts per million per year—now hovering at roughly 387 ppm, and climbing. But it may be that the Earth’s climate is resilient and can withstand a lot more CO2 and other greenhouse gases before flipping to some altered state. Or it may be that various positive feedbacks—light-reflecting white Arctic ice melting away in favor of warmth-absorbing, dark Arctic waters, et al.—underway have already doomed us to a much warmer planet.

In a bid to answer that question, a group of scientists decided to do what I do…interview the experts in a spirit of objectivity. Engineer M. Granger Morgan of Carnegie Mellon University, climate scientist Kirsten Zickfeld of the University of Victoria in British Columbia and physicist David Frame of the University of Oxford in England interviewed 14 "leading climate scientists" about three possible climate scenarios to ascertain what might happen depending on how much heat greenhouse gases end up adding. The experts ranged from Oxford physicist Myles Allen to climate scientist Tom Wigley, who retired from the National Center for Atmospheric Research in Boulder, Colo.—and is a repeat of a similar study conducted by Morgan in the mid-1990s.

The goal was to round up the most senior climate experts and gauge their opinions on what is most likely to happen under three scenarios: a high degree of warming, a moderate amount of warming and relatively little warming—as well as to judge when, if ever, the global climate might reach a "tipping point" into a completely altered state, one that might be less amenable to human civilization.

One main point from the result published in the June 28 Proceedings of the National Academy of Sciences: What was most uncertain to all 14 experts was clouds—specifically, whether clouds would exacerbate climate change by trapping more heat or ameliorate it by reflecting more sunlight. Regardless of the unknown effects of clouds, 13 of the 14 judged the odds better than even that if the extra heat trapped by greenhouse gases peaked and leveled off at seven watts per meter-squared by 2200—we would see an entirely new climate. In fact, nine of the experts judged the probability of such a "basic state change" in the atmosphere to be at least 90 percent, or more. That corresponds to a warming of as much as 12.5 degrees Celsius—a worst case scenario.

Fortunately, the human-induced extra heat at present hovers at about 1.2 watts per meter squared. That’s about half what the greenhouse gases already in the atmosphere are trapping; we’re gaining some counterbalancing cooling from other pollution, such as sulfur dioxide, and those mysterious clouds. All told, Earth’s average temperature has warmed by 0.75 degree Celsius, so far, as a result of that extra trapped heat.

The worst news? The interviewed experts don’t expect to be any more able to understand clouds and the other uncertainties by 2030—even if funding for such research were tripled in the next 20 years. That matches real world results, since the experts interviewed back in the 1990s were just as uncertain about clouds and the like as when re-interviewed in the 2000s. Or, as climatologist Stephen Schneider of Stanford University, one of the experts interviewed this time and last, told me last year: "We don’t know much more than we did in 1975" about climate sensitivity.

Fortunately, as investor Vinod Khosla is fond of saying (about himself and others): "Experts are usually wrong" when it comes to forecasting the future. Let’s hope he’s right about that at least, in this case.





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  1. 1. Dolmance 6:47 pm 06/28/2010

    The Republicans say it’s all a plot by you nefarious scientists.

    Why do you people insist on scaring people? Is it because you hate freedom?

    Link to this
  2. 2. freetoken 7:33 pm 06/28/2010

    Your selection of words is puzzling:
    "[CO2] now hovering at roughly 387 ppm, and climbing" and "…extra heat at present hovers at about 1.2 watts". In neither case is "hover" appropriate. CO2 is clearly increasing and rapidly, and subsequently so is the "extra heat" increasing.

    Also, what is the point of throwing in the Khosla quote at the end? Are you trying to undermine everything you wrote in the preceding paragraphs?

    Link to this
  3. 3. jtdwyer 8:37 pm 06/28/2010

    I’ve been informed that the climate modelers have things well under hand and that I just don’t understand the power of these modern computers. How could that be if there are crucial factors and fundamental issues that are not yet fully understood? Someone must not understand.

    Link to this
  4. 4. macuser 9:35 pm 06/28/2010

    Earth’s current climate is a "Goldilocks" climate: not too hot, not too cold, but just right. Nothing unusual is occurring.

    Occam’s Razor warns against adding unnecessary, extraneous variables to any explanation; Keep It Simple, Stupid ["KISS"] applies here. Adding an extraneous variable [such as CO2] to explain global warming only muddies the waters.

    The onus is entirely on the promoters of the "carbon" scare to show that their "CO2=CAGW" model [which says that CO2 will cause catastrophic AGW] explains reality better than the hypothesis of natural climate variability — a hypothesis that has never been falsified. Adding a minor trace gas to the explanation of natural climate cycles only leads to a false conclusion.

    Since the same crowd that believes CO2 drives the climate can not falsify the natural variability hypothesis, and since the CO2=CAGW conjecture has been repeatedly falsified [by the planet itself, no less], then it is time to jettison the mistaken belief that CO2 causes any measurable global warming. It does not, and no empirical, testable measurement has shown otherwise.

    On all time scales, CO2 rises as a result of rising temperature. Thus, rising CO2 is an effect of rising temperature, not a cause. The human component of the one-third rise in CO2 since the mid-1800′s is only about 3% of the total emitted. The rest of the rise in CO2 is entirely due to natural processes, such as ocean outgassing due to warming following the Little Ice Age.

    Demonizing CO2 makes some folks feel good, and it may get them financial grants from NGOs, but it can not be supported within the parameters of the scientific method. As Karl Popper explained, if a hypothesis is not testable, it is not even science.

    Skeptical scientists are on the right track. Which is as it should be, because every honest scientist is a skeptic, first and foremost. Those who put their faith in computer climate models have given up their skepticism. And without scientific skepticism, we would still be going to witch doctors to cure diseases.

    Listen to the climate skeptics; they are right, and the climate alarmists are wrong. The climate is acting normally. It is well within its historic parameters. Runaway global warming is a fiction based on a lucrative scam; it is not based on science or the scientific method.

    Link to this
  5. 5. YouCanHaveYourOwnOpinionNotYourOwnFacts 11:11 pm 06/28/2010

    @Macuser
    Please have someone explain Occam’s razor to you.
    You don’t eliminate variables, especially those which you know exist, because it "muddies the water". Climate is the result of many variables, which is why simplified models fail to predict even the most simple changes. You cannot say that others are outside the scientific method and then insist that the climate is well within historic parameters. You asserted this as fact, when the scientific evidence shows exactly the opposite. Your arguments against the evidence are nearly as well considered as Glenn Beck’s. Leave science to scientists. Go back to being a "macuser", and doing everything you can to deny the role your consumptive lifestyle might have in altering the climate.

    Link to this
  6. 6. Rmoen 11:27 pm 06/28/2010

    It’s great to hear climate scientist admit to numerous unknowns and not act like they have a crystal ball.
    – Robert Moen, http://www.energyplanUSA

    Link to this
  7. 7. aberforth 12:26 am 06/29/2010

    Climate change is due to variance in solar radiation not excess co2.

    Link to this
  8. 8. Frank Discussion 12:41 am 06/29/2010

    These people who claim global warming is a hoax are the same people who don’t ‘believe’ in evolution, who believed health care would create ‘death panels,’ who believe business shouldn’t be regulated even though banks and mortgage companies came within inches of destroying the economy, ad nauseam… Obviously they are not rational, so it is useless to try to reason with them. The results you’ll get are shockingly similar to those you’ll get from trying to reason with your pet cat.

    Link to this
  9. 9. Michael128 1:35 am 06/29/2010

    Maybe they are not making a position statement and reflecting the uncertainty, sort of like how good journalists are supposed to behave?

    Link to this
  10. 10. Michael128 1:38 am 06/29/2010

    Maybe they are trying to reflect the uncertainty and not making a position statement, sort of like how good journalists are supposed to behave?

    Link to this
  11. 11. gervster 7:46 am 06/29/2010

    Whether we’re right or wrong about global warming, there’s no downside to going carbon-neutral. If we’re wrong, we’ve at least accomplished energy independence; if we’re right, we avoided catastrophe and accomplished energy independence. Any way you slice it, action is better than inaction with respect to global warming.

    As far as I’m concerned though, I’ll side with the 13 of 14 climate experts who believe climate change is happening. We don’t know exactly what effect increases in CO2 will have, but typically when the effect is unknown – hope for the best, prepare for the worst.

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  12. 12. buddydaddy 10:45 am 06/29/2010

    macuser, please read an actual scientific study on this subject. You’ll see that the equation CO2=AGW is entirely testable and has been proven many times over. We can demonstrate in the lab how CO2 causes global warming, and how much warming it causes. We know how much atmospheric carbon we’re producing because we know how much fossil fuel we’re burning.

    Can you provide any data that says carbon doesn’t cause warming? Can you provide any data that says we’re not emitting as much carbon as scientists say we are? Of course not. Now go back to reading your Republican e-mails.

    Link to this
  13. 13. buddydaddy 10:50 am 06/29/2010

    Following your logic: If one is generally healthy, one should ignore the appearance of cancer cells as an extraneous variable.

    Link to this
  14. 14. Chris G 11:08 am 06/29/2010

    Some thoughts:

    "…the ever-present carbon dioxide we pump out from our lungs …"

    Animal respiration does not matter. This is because all of the carbon that we breath into the atmosphere was only recently pulled from the atmosphere by plants. The net effect is zero.

    @Dolmance,
    Well, on one side you have people telling you what you don’t want to hear, and what they are saying is based on very specific facts and figures that have withstood scrutiny for the last 100 years or so. On the other side, you have people telling you what you do want to hear, based on generally vague, inconsistent, and incorrect information, and accusations of malfeasance on the part of the former people.

    Clouds, let’s see. For decades now very smart people have been looking into whether their effect is positive or negative and there is no clear determination. Doesn’t that imply that whatever the effect is relatively small one way or the other? Relative to water vapor and CO2 that is, whose physical characteristics for long wave absorption can be verified in any physics lab.

    Robert Moen,
    The energy sector (fossil fuel dominated) has a stated goal of sowing a perception of doubt about climate change; thanks for playing your part.

    @aberforth,
    Really? The sun has been shining less brightly than average for some years now; meanwhile we continue to see record level global temperatures and ice loss. Over the instrumental record, solar energy has been flat while global temps have gone up. Please explain how the sun is causing this.

    JTDwyer,
    Hi, Someone has been feeding you a strawman argument. The power of a computer has nothing to do with the accuracy of a model; it just takes longer to get a result with a slower computer. Besides, the strongest indicators of climate sensitivity are paleologic studies rather than computer models.

    Link to this
  15. 15. aberforth 12:05 pm 06/29/2010

    @Chris G – you guys don’t keep quiet until some experts tell you.

    "There is no global warming due to human anthropogenic activities. The atmosphere hasn’t changed much in 280 million years, and there have always been cycles of warming and cooling. The Cretaceous period was the warmest on earth. You could have grown tomatoes at the North Pole" – Tad Murty

    Link to this
  16. 16. Chris G 12:15 pm 06/29/2010

    @aberforth,
    So, who is Tad Murty and what has he published lately?

    Can you answer my first question first?

    Link to this
  17. 17. Chris G 12:17 pm 06/29/2010

    You are suggesting that the current ecosystems would do well if transplanted to a cretaceous enviranment?

    Link to this
  18. 18. aberforth 12:23 pm 06/29/2010

    @Chris G
    Tad is an expert oceanographer with precise knowledge about global warming not those weirdos pushing green economy. No one likes to publish the truth because in the current economic world each organization lobbies for another organization to cash-in as much grant as they can and naturally the real subject becomes big and blown out of proportion.

    btw, the radiation from the sun is quite uneven resulting in the temperature imbalances every 100-200 years, this is quite normal.

    Link to this
  19. 19. Chris G 1:35 pm 06/29/2010

    @aberforth,
    Tad is an expert on tsunamis. I’m not sure how that makes him more qualified than others when it comes to the physics of short and long wave radiation, climate feedback systems, etc.

    Aside from approximately 11-year solar cycles, the solar irradiance has been very flat since we’ve been able to measure it directly.

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

    (I know it is a wiki; feel free to read the references and let us know if the wiki author misrepresented something.)

    Again, can you answer my first question?

    @Sisko,
    Don’t be daft. No one is claiming that CO2 is the sole driver of climate. It just happens to be the only thing that is changing enough lately to account for the observed changes using the laws of physics as we understand them.

    Human over population is the biggest problem; I’ve no doubt about that. But we are setting ourselves up for a double whammy of increased population along with a reduction of agricultural carrying capacity. Unless you are saying that changes in temperature and rainfall will have no effect on agricultural production.

    Link to this
  20. 20. Sisko 4:58 pm 06/29/2010

    @Chris- There is no reliable data that shows a warmer planet would not have a positive net effect on overall agricultural production.

    Link to this
  21. 21. hotblack 6:51 pm 06/29/2010

    …says the man with apparrently zero agricultiral knowledge.

    Link to this
  22. 22. hotblack 6:52 pm 06/29/2010

    well, at least I can spell agricultural…

    Link to this
  23. 23. Chris G 7:01 pm 06/29/2010

    Sisko,
    It’s a mixed bag.
    http://www.climatescience.gov/Library/sap/sap4-3/final-report/sap4-3-final-exec-summary.pdf

    You seem to be saying it is OK to roll the dice with our food supply. I grew up in an farming community; unusual weather is more often bad than good.

    Link to this
  24. 24. jerryd 10:58 pm 06/29/2010

    Even if CO2 doesn’t cause GW ocean acidification from it is a huge danger, killing 75% of the earth.

    Facts are we need to do the same things for national and economic security as we do for GW so let’s get busy!!

    Here’s how and save money at the same time,

    First we will never run out of oil, coal or most anything else, it will just get too expensive to extract.

    Facts are for most energy, solar PV/ CSP, wind and eff, conservation can serve most needs. Now add biomass, river/tidal kinetic, inherently safe, smaller nukes solves most of the rest.

    But what a world will we have if we burn most of the oil, coal? Even assuming no GW, the oceans will be dead from CO2 acidification and pollutions from them will make life not very good.

    What we need to do now is put the full cost of oil, coal in them and the above RE which are about competitive now will be the cost effective choices.

    It only takes $500 to build a 2kw windgen that puts out about 15-20kwhrs/day in many places that can supply a family both home and transport energy if well designed, not really anymore costly, in fact cheaper than fossil fuels even now. And lasts 50+ yrs.

    PV panels are now $2k/kw retail if shopped well which is cost effective with coal.

    Solar CSP is just a 5hp steam engine with 200sq’ of a trough collector that provides 15-25kwhrs/day of electric and 45-75kwhrs of heat. It can be built for under $5k retail in mass production.

    I drive my EV’s every day that get 250 and 600mpg equivalent. They can be built for under $10k and $6k. They use no more material, labor than NEV’s now built for that.

    There is no shortage of energy, it’s a political problem, not technical. We just need to get big coal, oil out of the way and stop subsidizing them and the rest will fall into place, hopefully before we kill our planet!

    Link to this
  25. 25. ormondotvos 11:26 pm 06/29/2010

    Thanks, Chris G. for debunking the ostriches.

    Link to this
  26. 26. jgrosay 11:14 am 06/30/2010

    Politicians are able to reach power just because somebody funds their campaigns. Having 2’000 cc minimun engine size cars is a wasting of oil and a terrible hit to green house effect gasing. Transport is responsible for more than 50% of energy use in the USA, there are a lot of technologies that can decrease this, but decreasing energy use will reduce both oil prices and oil companies size of market, two things that will greatly shrink the petrol business people revenues. One can imagine a lot of tax and non-pollution regulatory measures to stop that, but the ones that are earning a salary for this are the USA president and other politicians. Some say the right CO2 level is 350 ppm. Right now, we are at 386. Who cares?

    Link to this
  27. 27. gervster 3:15 pm 06/30/2010

    Jgrosay: Actually, it accounts for less than a third according to the 2008 EIA report. Little less than 30% if I’m reading it right. That being said it certainly is one of the bigger sectors consumption wise.

    http://www.eia.doe.gov/aer/pdf/pages/sec2_6.pdf

    Link to this
  28. 28. Sisko 3:46 pm 07/1/2010

    @chris- I am saying there is zero reliable data to support that a warmer climate threatens our food supply, therefore there is no good reason to put in place a "carbon tax" that would be extremely damaging to the economy.

    My point is that we need vastly more energy produced domestically and unless/until the additional sources of electricity production are on line we should not be shutting down current sources (say coal fired generation plants)

    Link to this
  29. 29. gzuckier 10:44 pm 07/1/2010

    In fact, the onus is on anthropogenic climate change deniers to explain not only what natural process is occurring which is making the climate mimic the energy retention effects of adding as much carbon to the atmosphere as humans have done; but in addition, what process is preventing the addition of this carbon to the atmosphere from increasing the retention of solar energy, as basic theory predicts it should.

    Link to this
  30. 30. richardebridges 10:59 pm 07/1/2010

    If man is responsible for the present climate change then how can we blame man when the present cycling started about the time when South America joined us. about two and a half million years ago? richardebridges@aol.com.

    Link to this
  31. 31. Sisko 12:49 pm 07/2/2010

    @Gzuckier- You are really funny or lame (not sure which)- If someone wants to implement a policy of limiting human released CO2 into the environment, and that policy is going to cost hundreds of billions to implement, and it is known that human released carbon is less than 2% of total carbon released annually, isn’t it incumbent upon the person wishing to implement this policy change to prove it is worthwhile prior to implementation?

    Do not implement the proposed policy:
    If a warmer planet is only different and not bad for humanity overall in the long run.

    If a reduction in the amount of human released carbon can not be proven to improve the negative consequences of a warmer planet (if they are proven to exist)

    Link to this
  32. 32. highlama 11:39 am 07/3/2010

    Climate change hysteria has become the most powerful use of fear mongering in history. Needless to say, those who are terrorized by it will not have their fears allayed easily.

    Climate change fears have also become, for many, an existential solution to their own petty lives … now they can "save the planet" and consider themselves to be real heroes. Never underestimate the value of an existential solution – it has been the basis of most modern warfare.

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  33. 33. shorewood 11:08 pm 07/3/2010

    What chicanery!

    First, "scientists" say that humans contribute to global warming. But, what qualifies a person as a "scientist?"

    Second, why would anyone believe that "scientists," as a group, know much more about it than you or I do? SOME scientists are qualified to judge, but, really, not very many. For example are botanists or genealogists qualified? I think not.

    Third, the experts mentioned in the article are not asked their evaluations of whether / how much humans contribute to global warming. They are asked only what happens GIVEN various degrees [pun?] of warming. The article doesnt even suggest that these experts believe that any global warming is occurring but it sure implies it.

    All-in-all, a very misleading article.

    Link to this
  34. 34. desotojohn 11:13 pm 07/3/2010

    I thought the Climategate email controversy scandal at the University of East Anglia’s (UEA) Climatic Research Unit (CRU) put this whole farse to rest. Why won’t these people give up? Please explain why the other planets are heating up also. Maybe there is something going on that we can’t explain. Nah, it’s easier to blame everything on mankind.

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  35. 35. mo98 1:42 am 07/4/2010

    Worth noting was the observed immediate increase in the contrast between day and night temperatures around the world when clouds of missing contrails contributed to a lack of man-made influence on everyday climate following 2001 septemeber 11.

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  36. 36. Dr. Strangelove 9:45 pm 07/5/2010

    Finally, an unbaised climate change article from SciAm! If the climate experts admit the effects of clouds are unpredictable, WTF are all these fear mongering by IPCC, et. al.?!

    The honest thing to say is simply: "we can’t predict climate change, hence all advocacies for or against fossil fuels and CO2 emission are political not scientific."

    Link to this
  37. 37. wlhgmk@gmail.com 2:21 am 07/6/2010

    An interesting observation is how large the annual fluctuation in the Carbon dioxide level is when compared with the annual increase. This is allegedly due to the absorption of Carbon Dioxide by the northern hemisphere land vegetation. This suggests that if we increased, for instance, forest cover we could suck up a lot of carbon but conversely if we denude our Northern forests we could be in deep trouble.

    Link to this
  38. 38. mike cook 6:03 am 07/6/2010

    Part of the equation of figuring out how much warming occurred during the 20th century is to accurately summarize what the data from the temperature measurements made in the 19th and early 20th centuries actually meant. This is actually a process of estimation, because after the thermometer was invented a lot of data was generated from a lot of sources, so representative sampling is required, which takes some type of procedure for screening out less reliable anecdotal data.

    Early temp measurement was basically eyeball on mercury column, which can cause error because humans tend to exaggerate extremes. It is always fun to report a record high or a record low so a little wishful thinking produces rounding errors when the temp is "almost" 117 F. above or -44 below.

    The next source of error in 19th and early 20th century data is that so little was collected in certain critical places of the Earth, like most of the Southern Hemisphere and Antarctica. The Southern Hemisphere is mostly ocean so most of the data was collected from ships’ records or a few reliable historical data stations in South America, Africa, and Australia. The same is true of Antarctica, where long-term weather data stations were maintained at only a handful of places.

    So a great deal of estimation has gone on in the Southern Hemisphere, and that could have tended to make things seem to have been just a tad bit too cold. When you start with a base that is slightly too cold, it is easy to conclude a slight increase in warming has taken place, as as 0.27 degrees C.

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  39. 39. gervster 7:33 am 07/6/2010

    Seven answers to climate contrarian nonsense:

    http://www.scientificamerican.com/article.cfm?id=seven-answers-to-climate-contrarian-nonsense

    Enough said.

    Link to this
  40. 40. Sisko 10:04 am 07/6/2010

    @Gervster- LOL at your lack of independent thought by posting an old article and saying "enough said"

    Can you point to ANY reliable data that will demonstrate that a warmer planet is worse for humanity in the long run??? All I have read are articles that try to point to any change and exclaim how that will be terrible for those individual affected. Well sorry, but the reality is that the climate will change over time and humans will have to adapt.

    Link to this
  41. 41. jtdwyer 1:35 pm 07/6/2010

    I understand from Wikipedia that the Carboniferous period extended from about 360-300 mya.
    - Mean atmospheric CO2 content over period duration: ca. 800 ppm (3 times pre-industrial level)
    - Mean atmospheric O2 content over period duration: ca. 32.5 Vol (163 % of modern level)
    - Mean surface temperature over period duration: ca. 14 °C
    (0 °C above modern level)
    - Sea level (above present day): Falling from 120m to present day level throughout Mississippian, then rising steadily to about 80m at end of period

    I wouldn’t jump to the conclusion that current ecological impacts are trivial, but since we’re only considering about 100 years compared to the 60 million years of the Carboniferous period, they may be survivable. However, the rate of change is alarming: it will produce challenging conditions.

    Interestingly, the Carboniferous period produced the overpopulation of plants and the world’s supply of coal. The increased O2 levels contributed to the following production of giant dinosaurs. The current overpopulation of humans has been powered by the carbon stored during this period. Our actions could produce our demise and a return to conditions favoring giant plants…

    Link to this
  42. 42. gervster 2:14 pm 07/6/2010

    Eight months is too old? Good to know. Fortunately though, I’m pretty sure you just argued against yourself. To claim that we’ll have to adapt inevitably implies that climate change will be disruptive to humanity. But, for the time being I’ll go along with it.

    Please enlighten us all: How will increased severe weather patterns (heat waves, droughts, tropical storms all inclusive) glacier retreat, ocean acidification, and sea level rise – to name a few without even touching basis on the ecological impacts – prove beneficial to humanity?

    Granted, in the immediate short term there could be local benefits. But let’s face it, climate change poses a pretty serious threat to our future.

    Link to this
  43. 43. mike cook 11:04 pm 07/6/2010

    Let’s make one thing perfectly clear–if it happens (as I believe) that we are on the cusp of a sudden-onset return to a Little Ice Age, then the effects of cooling can not by any stretch of the imagination be laid at the feet of humanity destabilizing the climate by allegedly making things briefly warmer in the late 20th century.

    Supposedly that could happen by Arctic and Icelandic ice melt disrupting the deep thermal haline currents of the oceanic conveyor system. However, last I heard the deep ocean currents seem to be as healthy as ever.

    Droughts are something that have always come and gone according to an unknown schedule, and drier air sometimes happens because the general climate is colder. Similarly, sometimes glaciers do not recover the summer melt off because a cooler climate can mean less local precipitation. Without snow to replenish them, glaciers can wither away, even though the average ambient temperature of the air moving over the glacier is slightly cooler.

    The Sudden Onset Little Ice Age may well bring drought in unusual places and severe storms. A SOLIA event may have been delayed a couple decades by humanity’s adding to the trace greenhouse gas carbon dioxide in the atmosphere, but that feeble input won’t stop the long-term prognosis for our planet, which is to drive most living things to extinction with ice.

    Singular events like a Yellowstone supervolcano or an asteroid impact could really speed things up, but I think that once the present heat wave cooks the Atlantic coast for a month or two everybody had better get ready get ready for a really cold winter.

    Which brings me to another prediction. Wheat supplies are already failing world wide because of wheat rust, a plant disease. When cooler weather starts messing with Canadian wheat production the world could get really hungry.

    Link to this
  44. 44. Beam me up Scotty 8:54 am 07/20/2010

    You fail to answer the question you pose. You fail to make the information you provide in this article relevant.
    I was disappointed.

    Link to this
  45. 45. mike cook 10:24 am 07/20/2010

    Man is not responsible for it, but I say that a Sudden Onset Little Ice Age (SOLIA)approaches and will surprise us this coming winter.

    I make this prediction because of the freezing out of the troposphere due to the unusually extended solar minimum. The exact effect of a lack of sunspots is very poorly understood, except that in the long term a lack of sunspots seems to coincide with dramatic global cooling.

    We have evidence of SOLIA events before in history, in Peruvian glaciers and mammoths frozen while munching daisies. My guess is that the missing sun spots do not cause a decrease in solar energy reaching the earth, but the wavelengths of the energy and in the case of ejected particles, the charge, are different which effects our troposhere and (indirectly) cloud formation.

    This year has been hot for much of the USA and some parts of Asia, but is NASA really crunching the numbers with a fair and balanced consideration of other weather cycles, such as the El Nino and La Nina, which are whipsawing us at the moment?

    No matter, because at the end of the day the clouds will respond to the solar minimum and this winter will be brutal. Perhaps this SOLIA will push us prematurely into another million-year big ice age, all at the whim of the sun and with the puny human production of greenhouse gases at best delaying the freeze-out process for a few months.

    The good news is that SOLIA won’t stop Canadian, Dakotan, and Montanan wheat production which is booming this year because of ample rain fall. Wheat has a short growing season and the extra long days of northern hemisphere summers will still bless the fields–all Dakotans will just want to snowbird to Florida and Arizona in the winter.

    Link to this

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