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All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

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Comments 108451 to 108500:

  1. IPCC Reports: Science or Spin?
    Spencer is really naive in my opinion. It is irresponsible to just effectively say 'science should just be a direction-less talking shop'. The IPPC was set up to assess the science and give advice. The 'goal' would change as the science changes. Maybe his indecisive personality is reflected in the fact that he mixes religion and science. Really his whole philosophy is that people can choose what to believe. Does he actually get things done? Or does he argue with himself all day trying to decide whether to mow the lawn or not?
  2. Newcomers, Start Here
    It isn't just adaptation to climate that is a problem. Changing climate also results in changing diseases and vulnerabilities to other changes, which are indirect issues. eg. species of tree may be able survive a changed climate, but they may be susceptible to a disease that climate brings with it or other invasive species. Polar bears have led a relatively isolated existence, warmer conditions may wipe them out because of a lack of immunity to invasive disease carried by other species that migrate into Polar bear territory. Humans have a high track record of introducing invasive species that wipe out complete populations of native species. Climate change can do the same thing.
  3. IPCC Reports: Science or Spin?
    Let me repeat myself: Despite strong political reasons for them not to endorse, the following countries endorsed the IPCC 2007 reports because the science was undeniable: United States of America - Fossil fuel-based economy, strong lobby efforts opposed to regulating fossil fuel emissions Saudi Arabia - World's largest producer/exporter of oil China - Rapidly industrializing using coal-fired power plants India - Rapidly industrializing using coal-fired power plants The IPCC WGI Report (2007) concluded: “Most of the observed increase in globally averaged temperatures since the mid-20th century is very likely due to the observed increase in anthropogenic greenhouse gas concentrations.” 130 countries endorsed the reports, and since 2007, no scientific body of national or international standing has maintained a dissenting opinion. Politics? Hardly. Spencer, as a scientist, should know that one cannot make such grand claims without supporting evidence.
  4. Climate Change: Past, Present, and Future
    As for "a clear MWP hotter than today", that *would* be the final nail in the coffin of the idea that climate sensitivity is a small or manageable number. The last thing anyone wants is this or any other confirmation that climate sensitivity is on the much higher side rather than the lower.
  5. Climate Change: Past, Present, and Future
    Chris, the discussion was about agriculture. I very much doubt anyone with any brains would use goats for anything but reclaiming degraded growing areas. They're particularly good for areas within a farm infested with blackberry and the like. (Though I personally think pigs are better for this.) I know of no grain crop that grows under forest cover, especially not native forest.
  6. Newcomers, Start Here
    johnd, the word adaptation is used both in the sense of evolutionary adaptation or of adaptive capacity of the individuals. The former is a very slow process, it is passed to offspring and it takes many generations for small gradual changes; fast reproduction and short lifecycle would be an advantage. The latter is much faster but it is not passed to offspring. Polar bears cannot count on evolutionary adaptation, it's much too slow. Also, they are a very specilized and occupy a narrow ecological niche. Theese facts strongly limit their capability to adapt. In any case it's a race with time, the faster the change the less the odds that a specie will survive a change. And don't forget that climate change adds to other stresses.
  7. Newcomers, Start Here
    It seems to me that the problem facing polar bears is not so much their supposed inability to adapt to a changing, warmer climate, but trying to maintain an environment, any environment, that puts some distance between themselves and humans. I don't think those who fear the inability to adapt fully appreciate just how rapidly most species can adapt to new completely different environments. Unless there is some special genetic makeup within the polar bear DNA that gives it an inability to adapt, it should be able to adapt as many other species have adapted in the past, and are still doing so, moving from one region to another transported over land or shipped by sea, or now days at times by air. Is there any accumulated evidence where the polar bear has demonstrated a special inability to adapt to different climatic conditions or is it just supposition?
    Response: "...it should be able to adapt as many other species have adapted in the past"

    This seems to be a common misconception - that animals will simply adapt to climate change. Throughout Earth's history, there have been periods where climate has changed so abruptly, animals have not been able to adapt quickly enough. These periods are known as mass extinctions. In the Permian mass extinction, between 80–95% of all marine species went extinct. In the Triassic mass extinction, around 80% of all land quadrupeds went extinct.  Virtually no large land animals survived the Cretaceous mass extinction 65 million years ago (this is famous for the demise of the dinosaurs). Our current period is being described as the 6th mass extinction in Earth's history.
  8. Climate Change: Past, Present, and Future
    Doug's right, we are off topic but adelady @ 27 writes: Goats are brilliant at clearing weed infested land, but finding enclosures that are both movable and secure enough would be an issue. Goats are brilliant at clearing weed infested land because they rip plants out by the roots, ie, they literally eradicate. Consequently, they can be a huge problem with regard to deforestation. Coming back on topic, JMurphy @ 29: Identifying a clear MWP hotter than today would not be the final nail in anything. While it would change the parameters of our debate around climate sensitivity and forcings, I'd like to think that most of us who participate in these discussions do so not to score points but to come to a better understanding of the fascinating intricacies of the workings of the world in general and climate in particular. AWG may have been the catalyst to our musings but the science is never *settled* if you are a genuine scientist! :-)
  9. Models are unreliable
    Tom, thanks, and that link does appear to work for us in the Great Unwashed Masses. Vardi makes an excellent point.
  10. IPCC Reports: Science or Spin?
    I heard somewhere else that a good amount of the "old" or year to year sea ice within the arctic has recovered some since 2007. Is that true?
    Response: There was a slight rebound in the 1 to 2 year old ice but a continued drop in the 2+ year old ice:



    The result is that Arctic sea ice volume (eg - the total amount of ice) reached record low levels in 2010:

  11. Newcomers, Start Here
    What the "polar bears will just adapt" crowd seem to not understand about evolution, is that adaptation to a changing environment is far from guaranteed. The major mass extinctions in the past have all occurred when environmental change was too rapid and/or environmental stress was too strong. This is what we're seeing today. Plus, mass 'extinction' is perhaps a misnomer, as some events are marked by extinction rates dramatically elevated above background levels, while others are marked by dramatically reduced speciation rates. I think our double wammy of human encroachment and environmental change is causing both to occur at the same time.
  12. Models are unreliable
    A good, short, essay on the role of computer models in science is in the journal Communications of the ACM, the September 2010 issue, page 5. I can see it on line for free, but I don't know if that's because I'm an ACM member: Science Has Only Two Legs.
  13. Newcomers, Start Here
    @CW: that's your rebuttal? Weak. Changing light bulbs (preferabley to LEDs) and driving hybrid/electric cars is just smart, regardless of the overwhelming amount of evidence supporting AGW theory. Oil is too valuable to use as fuel.
  14. Newcomers, Start Here
    Ignoring Doug's correction, what you say is right, CW: we should go ahead and take these poor ------s out in the next 50 to 100 years with our paltry 3-7 C warming, because there's no way they could continue to evolve over the next 20,000-30,000 years as insolation slowly creeps toward max. Why stretch it out for them? Indeed, let's go ahead and make that choice for all the other species we couldn't possibly be affecting by our slight changes to the biosphere. Who needs em? What a work is man! How infinite in reason! Or was it density or greed or something like that . . .
  15. Newcomers, Start Here
    I believe you're mixing up BP w/AD, CW.
  16. ClimateWatcher at 11:23 AM on 1 October 2010
    Newcomers, Start Here
    By the way, if you can repress the memory of the HCO ( the peak just prior to the blue dot which marks the present ), and are still convinced that changing your light bulbs ( or as Nissan would sell you, driving a 'Leaf' ) will have any bearing whatsoever on the Ursus Maritimus ( polar bears ), do reflect that nature is going to irradiate the Arctic with greater summer sunshine than present for most of the next fifty thousand years:
  17. IPCC Reports: Science or Spin?
    Yes, nicely done Graham. Worth noting too that whatever "political pressure" may be operating on the IPCC in a general sense is operating in the direction of toning down warnings, as a result of countries such as the US and Saudi Arabia being determined that nothing will be allowed to slow down the profit stream from oil. And that there will be none of this regulation nonsense getting in the way of [polluting] business as usual. Since there has to be consensus this results in only the lowest threat levels being acceptable to all. Whenever individual climate scientists are able to speak without political pressure (and this pressure operates within countries too, again the US being a prime, though not the only, example) their real views are much more gloomy than the IPCC consensus position.
  18. Newcomers, Start Here
    CW's chart is from NOAA, Rob. They've got an interesting discussion of paleoclimate information available. It's a little long in the tooth, last updated 2006. For some fresher Arctic paleo information, see History of sea ice in the Arctic (Polyak et al, 2010) and Temperature and precipitation history of the Arctic (Miller et al, 2010)
  19. Newcomers, Start Here
    ClimateWatcher (#6)... BTW, where does that diagram come from? What's the source of the data? Robert Way would know far better but the numbers look a little fishy to me. And it's always a red flag if there is no source referenced.
  20. Newcomers, Start Here
    While the comment about the bear de-evolving it's white coat is silly (it would require a change in the bear's phenotype which would take a very long time indeed to evolve) the previous comments about the Hudson Bay population are interesting. This appears to be an example of learned behaviour which is quite different from evolved behaviour (or evolved physical characteristics). So it's quite possible that the bears will learn to adapt to ice free summers where possible as they are intelligent long-lived animals. However this has absolutely nothing to do with evolution.
  21. NASA-GISS: July 2010-- What global warming looks like
    Not to reignite the flames of controversy over whether 145 x 10^20 Joules per year of increased energy per year retained on Earth must certainly remain invisible to us but rather just to follow up on the original topic, here are are a couple of items looking back on this past summer, from NASA-GISS: 2010 — How Warm Was This Summer? How Warm Was Summer 2010?
  22. New temperature reconstruction vindicates ...
    KR: ...long term sequestration of CO2 involves plants that are not then burnt, eaten, or rotted away. Also foraminifera, coccolithophores, diatoms. C in C02 ends up in hydrocarbons, carbonates. Of course we're short on enormous shallow seas these days.
  23. Newcomers, Start Here
    fydijkstra... What I believe you are also pointing out with your comments is that it takes many thousands of years for evolution to allow these species to adapt. They are not going to readapt to an ice free environment over the course of a few generations. It's important to protect species for obvious reasons, but I keep saying that polar bears are the canary in the coal mine. They should be a sign to us that something serious is afoot. ClimateWatcher (#6)... I would point out that what you are claiming here does not account for any further rise in temperature. By this chart you might not conclude that the HCO was warmer than today. But that placed aside, what we are looking at is a rise of another 2-3C in global average temps (more in high latitudes) in this century. As a species polar bears have very definitely never seen such conditions.
  24. New temperature reconstruction vindicates ...
    Follow up from #85 Of course there's an easy way of assessing the significance of the difference between the trends - correlate the difference between the 1990s and the 2000s against the position in the series. This gives a correlation coefficient of -0.07, 95% confidence interval of -0.67 to +0.58. As this confidence interval intersects zero (and as I indicated previously is a very wide interval) there's clearly no significant difference between trends in the 1990s and the 2000s as measured by the annualised satellite data. For this analysis to be statistically significant the correlation would have to be (0.58 - 0.67)-1 = 0.91 which would be very difficult to achieve with this system, even if we were seeing clear evidence of runaway global warming (or cooling) over such a short time frame.
  25. New temperature reconstruction vindicates ...
    #81 johnd at 06:47 AM on 1 October, 2010 wrote: "If we look at the carbon cycle where the the natural sources and sinks exceed anthropogenic emissions by a factor of 30, and those natural sinks each year sequester approximately half of the man made emissions" Perhaps you might like to consider the difference between short and long term sequestration. I was referring to the digging up of (semi-)permanently sequestrated carbon.
  26. New temperature reconstruction vindicates ...
    johnd - My point was that seasonal CO2 variations due to the growing season are very definitely not the trend - and that you cannot count on large seasonal variations to take care of a multi-decade CO2 increase.
  27. Newcomers, Start Here
    fydijkstra "So what's wrong with adaptation of the polar bear? If it does not need its white color any more, so what?" And how long did that earlier adaptation take? 50 generations, 100 generations, 1000 generations? This kind of evolution does not happen in the space of a few years or a few generations. Nobody's suggesting that we should stand in the way of natural evolution. The kind of time scale our emissions are imposing is not conducive to natural evolution.
  28. New temperature reconstruction vindicates ...
    KR at 08:09 AM, the rate at which CO2 is being moved deeper in the oceans will be tied to the rate at which the heat also absorbed at the surface is redistributed and moved deeper, and that, whilst subject to great discussion, is more reflective of shorter rather than longer term circulation.
  29. New temperature reconstruction vindicates ...
    Matthew @80, I concur with kdkd, or rather Hansen does ;) "Contrary to a popular misconception, the rate of warming has not declined. Global temperature is rising as fast in the past decade as in the prior two decades, despite year-to-year fluctuations associated with the El Nino-La Nina cycle of tropical ocean temperature. Record high global 12-month running-mean temperature for the period with instrumental data was reached in 2010." From: Hansen, J., R. Ruedy, Mki. Sato, and K. Lo, 2010: Global surface temperature change. Rev. Geophys., in press, doi:10.1029/2010RG000345.
  30. New temperature reconstruction vindicates ...
    Matthew #80. "Kdkd 2000-2009 warmed about .15c, which is below the 1990's. Is that true? Nope. Firstly you can't really assess trends properly over such a short time period in isolation due to a lack of statistical power. The difference in trend is almost certainly not statistically significant even before correcting for autocorrelation. The calculation for actual statistical significance is fiddly so I'm not going to do it, but with 10 paired data points it would require quite a large difference in correlations to be significant (probably greater than r=0.6 from memory) - the observed difference in correlation is only 0.15 which is definitely not statistically significant for 10 paired observations. Looking at the satellite data for 1990-1999 and comparing it to the satellite data for 2000-2009, the mean anomaly for the 2000s is 0.25 deg C greater for the 2000s period than for the 1990s period (95% confidence interval: 0.095-0.40).
  31. New temperature reconstruction vindicates ...
    johnd - Seasonal variation is cyclic; what goes in comes out. Actual long-term sequestration of CO2 occurs through rock weathering, subduction in ocean zones, and the formation of those hydrocarbons we're so rapidly burning. The long term trend is what's important, currently +2ppm/year, not seasonal variations. The only long term sequestration of CO2 involves plants that are not then burnt, eaten, or rotted away. That's a pretty small portion.
  32. Same Ordinary Fool at 07:37 AM on 1 October 2010
    Newcomers, Start Here
    The story of polar bears coping without sea ice has already been filmed. Several years ago I saw an hour long show about a mother and cub who missed the departing sea ice. They were stuck on shore for the rest of the summer. They missed the salmon run, because they didn't know about it. They did find the berries. Mom was pretty gaunt by the end of the summer. Unlike in the Arctic, the Hudson Bay sea ice disappears completely during the summer. So entire subpopulations there are forced onto land. The good news is that the polar bears have evolved the ability to survive a summer long fast. The bad news is that in a warming world the time on shore is getting longer. Ironically, when the multi-year ice becomes even thinner, there will be some new areas that the polar bears can move into. These are areas where the ice is now too thick for the seals to maintain their breathing holes. fydijkstra @ 5:59Am.....The other evolved traits that make it the perfect maritime bear, work against it on land. Its big and slow. Its calorie requirements that are currently met by seals (an adult polar bear eats only the fat) can't be met on shore. And, most importantly, its the grizzly bears that win in fights with polar bears (if only the polar bears learned to use their nose butt...).
  33. New temperature reconstruction vindicates ...
    KR at 07:14 AM, the CO2 sequestration of the oceans and the plants and soil are divided roughly equal. The drop in CO2 levels that coincide with the seasonal growing periods in each hemisphere show that the plants and soil are a significant destination for CO2 with a capacity that is only partly utilised for a portion of each annual cycle.
  34. New temperature reconstruction vindicates ...
    johnd - Actually, much of the anthropogenic emissions are going right into acidifying the oceans. It takes quite some time for that absorbed CO2 to move deeper. The rate required to be absorbed by the environment and not change ocean pH would be much much smaller than 50% of current emissions.
  35. New temperature reconstruction vindicates ...
    Nick Palmer at 03:20 AM, regarding your comment of digging up CO2 that took millions of years to sequester. If we look at the carbon cycle where the the natural sources and sinks exceed anthropogenic emissions by a factor of 30, and those natural sinks each year sequester approximately half of the man made emissions, then one could make a case showing that in fact man is only releasing carbon in one year that took two years to get down there.
  36. New temperature reconstruction vindicates ...
    Kdkd 2000-2009 warmed about .15c, which is below the 1990's. Is that true?
  37. New temperature reconstruction vindicates ...
    KL #74. We've been through the scientific argument many many times. You seem to claim that the ocean heat content data is capable of falsifying the remaining evidence for anthropogenic global warming. You do not seem to have any other 'evidence' to support this position. A large and important part of your position is the need to maintain the pretence that the existing measures of ocean heat content are accurate enough to draw strong conclusions. It has been demonstrated to you many many times that it is not. As you have no other argument to support your position, you maintain the position regardless of the evidence presented to you (like the 'flattening of temperature post 1998' claim that you cling to as well), I think that repetitive rubbish is a fair comment which summarises your argument well.
  38. Positive feedback means runaway warming
    hadfield - Your statement "a system with positive feedback is by definition unstable" is incorrect, a system with a gain < 1 is stable, as discussed at some length here, and in better detail on the advanced version of this page. Total stable increase for a particular gain (g<1) and forcing (f) is, if you work the math: V = f / (1-g) The oft-quoted 3oC increase for a doubling of CO2 (forcing = 1oC) represents a gain of 0.666. This, incidentally, works for negative feedbacks as well - gains with an absolute value < 1.0 are always stable. Differing time constants may cause some oscillation before settling, but systems with |g| < 1.0 are always stable. Gains > 1 don't tend to exist in natural systems (as they would require infinite energy!); they're pretty common in electronics, amplifying values until you hit the limits of the power supply.
  39. Newcomers, Start Here
    The polar bear evolved only 100,000 years ago from the brown bear. In fact it is still the same species: brown and white bears can mate and reproduce. The white color of the polar bear is useful in its present habitat. This white color was developed because the survival rate of white variants was higher than of dark variants. If the bear has to change its habitat, it will adapt again, and probably lose its white color. This is simply how evolution works. It's the same as when humans migrate from Africa to Europe, as they did 50,000 years ago. They lost their black skin pigments, because in Europe their skin needed more intense UV-exposure to produce vitamin D than in Africa. So what's wrong with adaptation of the polar bear? If it does not need its white color any more, so what? The bear as a species is not threatened by climate change, but by human overpopulation.
  40. Positive feedback means runaway warming
    OK. The trouble with addressing "sceptic" claims is that they are often rather incoherent, so it can be damned hard to work out they are in the first place. If you have any examples of the claim you are addressing, that would help focus the discussion. In the absence of that, I can think of two versions of the "sceptic" claim. The first is that a system with positive feedback is by definition unstable. "Alarmists" are always pointing to positive feedbacks, some of them with short time scales like the water vapour feedback and ice-albedo feedback. But the climate is clearly not unstable so the positive feedbacks must not exist, or must be outweighed by negative feedbacks. The answer to this is that there is a large negative feedback that is fundamental to the Earth system and that is not usually identified as a feedback, namely the Planck feedback as I've discussed earlier (see also the recent article by Chris Colose on Realclimate). That feedback on its own dictates that the Earth's climate sensitivity will be fairly low. The evidence is that there are several fast positive feedbacks that act to increase the sensitivity, but nowhere near enough to make the system unstable. A second version of the claim might be that "alarmists" are saying the carbon cycle feedbacks will cause runaway warming a la Venus. The problem with this claim is that no "alarmists" are actually saying this, except Jim Hansen who has suggested it as a very remote possibility, but obviously one with huge consequences. Your discussion of the logarithmic dependence of the greenhouse effect on greenhouse gas concentrations tells us one reason why this runaway warming is not easily triggered. The fact that the Earth has not done so in the past also shows us it's hard to set off. Neither of these things indicate that it's completely impossible. To be of any help in avoiding confusion, your article needs to be clear about what claim it is addressing. At the moment it's not. Specifically, it conflates fast and slow feedbacks.
  41. Newcomers, Start Here
    One more thing: it's unfair to compare Arctic temps during the HCO to current global averages; we should compare modern Arctic temperatures instead. Overall, we see the rate of change is about twice the observed rate, with some regions exhibiting increases of 2 to 3C, putting the current warming in the same range as ClimateWatcher's map.
  42. Newcomers, Start Here
    @CW: "unfortunately, just like the bears of Yellowstone, the Polar Bears tend to BENEFIT from human settlements by raiding their garbage." How about humans? How do they benefit from increased human/bear interactions? You have to realize bears who raid garbage dumps near human settlements are also likely to be shot, which isn't very good for them either. "That aside, temperatures were much warmer during the Eemian and the HCO for thousands of years." Actually, there were no actual polar bears in the Eemian: they started to diverge from brown bears 150,000 years ago, but the real differentiation occured later, perhaps even as late as 20,000 years ago. Also, temperatures weren't "much warmer" everywhere in the HCO (according to your map). What's to say polar bear populations didn't congregate to Northern Quebec, where it was actually colder, or Greenland and the Behring strait, which were as cold as today? Overall temperatures may have been as high as 1C above the baseline, but we're already past the 0.5C mark, and likely to go above the highest estimates for the HCO before 2050. Furthermore, not everyone agrees the HCO was warmer overall. Some studies claim only a 0.2 to 0.6 increase (which means we could have passed the HCO already), while others claim there was an actual decrease in SST at the time. From the abstract of Tropical Pacific climate at the mid-Holocene and the Last Glacial Maximum simulated by a coupled ocean-atmosphere general circulation model: "Simulations for the mid-Holocene (6000 years before present: 6 ka) and the Last Glacial Maximum (LGM: 21 ka) have been performed by a global ocean-atmosphere coupled general circulation model (GCM). After the initial spin-up periods, both runs were integrated for about 200 years. For 6 ka the model shows an enhanced seasonal variation in surface temperature and a northward shift of the African and the Indian summer monsoon rain area. Overall circulation features in the tropics correspond to a strong Walker circulation state with negative sea surface temperature (SST) and precipitation anomalies in the central Pacific and positive precipitation anomalies over the Indian and Australian monsoon regions. It is noted that there is about a 0.35°C cooling of the global mean SST." (emphasis mine) "Sorry ladies," Stay classy. "this is one of the most egregious errors of the global warming campaign." First, it's not a "campaign", it's science. Second, you have yet to make successfully make the case for any of your affirmations. Careful, your bias is showing, and it's kind of ugly.
  43. Newcomers, Start Here
    Why are some so blase about the supposed survival of species that have survived thus far ? Maybe they know more than those actually working in this area ? It would seem they believe so. However, I refer to the experts in the field : "We have found that polar bears actually survived the interglacial warming period, which was generally warmer than the current one," Lindqvist says, "but it's possible that Svalbard might have served as a refugium for bears, providing them with a habitat where they could survive. However, climate change now may be occurring at such an accelerated pace that we do not know if polar bears will be able to keep up." Ultimately, she notes, the polar bear species may prove less adaptive. "The polar bear may be more evolutionarily constrained because it is today very specialized; morphologically, physiologically, and behaviorally well-adapted to living on the edge of the Arctic ice, subsisting on a few species of seals," she says. Ancient DNA from Rare Fossil Reveals that Polar Bears Evolved Recently and Adapted Quickly Charlotte Lindqvist, Stephan Schuster, Yazhou Sun, Sandra Talbot, Ji Qi, Aakrosh Ratan, Lynn Tomsho, Lindsay Kasson, Eve Zeyl, Jon Aars, Webb Miller, Ólafur Ingólfsson, Lutz Bachmann, and Øystein Wiigd. Complete mitochondrial genome of a Pleistocene jawbone unveils the origin of polar bear. Proceedings of the National Academy of Sciences, Mar. 1, 2010 'Rubbish !', says the so-called skeptic, I believe what I want to believe...
  44. It hasn't warmed since 1998
    @Eric (skeptic) #63 Bear in mind that increased water vapour (leading to increased clouds and precipitation) would also be in the (generally) much bigger gaps between any clouds. Some confuse water vapour (invisible and a powerful greenhouse gas) with condensed water vapour (steam) which makes up clouds.
  45. New temperature reconstruction vindicates ...
    @adelady #76 Over many hundreds of millions of years volcanoes have been releasing CO2 from non-biological subterranean sources of carbon. Without life sequestering the carbon back down underground again, CO2 would continue to build up. Life as a whole acts as a negative feedback to prevent CO2 buildup thus stabilising temperatures to its benefit. One element of life (Homo Sapiens Fatuus) has recently been acting as a positive feedback. As you say, we are digging up in a few decades what took millions of years to get down there.
  46. Newcomers, Start Here
    ClimateWatcher: "The polar bears survived the millenia long Eemian and the Holocene Climatic Optimum just fine:" C'mon CW, use a few of those brain cells of yours. Assuming you were correct, how many cities, villages and human civilisations did the polar bears encounter when they migrated and survived? (5million in the Holocene versus 6billion today, 9billion in 2050). Even if today they were not endangered by global warming, every species on the planet is endangered by human growth and exploitation of resources. If you add to that, global warming, then polar bears haven't a hope in hell.
  47. Newcomers, Start Here
    ClimateWatcher, given continuation of the rate at which the Arctic has been warming the discrepancies shown on your map, even if accurate, would all be overtaken within a few decades. Also, polar bears and brown bears remain completely inter-fertile even today - though neither can survive for long in the other's primary habitat. Dentition shows that the 'modern' polar bear has been around for less than 20,000 years... long after the Eemian. Earlier 'polar bears' were much less adapted to a life on sea ice and thus able to survive warm periods on land like the brown bears they interbred with. If current polar bears were forced to survive on land their numbers would be vastly reduced and they'd be forced into brown bear territory... where they would inter-breed and quickly cease to exist as a separate evolutionary offshoot. Yes, the imposition of hunting restrictions was clearly responsible for the polar bear recovering from near extinction up to a stable population... just as the loss of sea ice is now clearly responsible for the reversal of that trend.
  48. Newcomers, Start Here
    Wow, I'm really sorry, I could have sworn cruzn246 had posted that comment. I guess my coffee hasn't started kicking in yet. Please disregard the last two paragraphs as they were written with cruzn246 in mind (but not the first one after the colon, that still applies). Sorry for that, CW. We disagree on some things, but you're clearly not the trolling denier type (unlike cruzn246).
  49. Is Greenland losing ice? (psst, the answer is yes, at an accelerating rate)
    HumanityRules, the graph you show is Surface Mass Balance (SMB), just part of the story. The mass balance is reported in table 5. You can see that, altough none of the values is statistically significant, there has been a reduction from +22 for 1962-1990 to -36 (km3/yr WE) for 1998-2003. Also, the authors warn: "However, the ‘‘real’’ mass balance is probably substantially more negative because we do not take into account dynamical factors" and "our best estimates of -14 ± 55 km3 yr-1 and -36 ± 59 km3 yr-1 mass balance for 1993 – 1998 and 1998 – 2003 are much less than the -59 km3 yr-1 and -80 km3 yr-1 mass losses derived from airborne laser surveys for the same respective periods [Krabill et al., 2004], the latter including dynamical effects."
  50. Newcomers, Start Here
    @cruzn246: was posting that big graph really necessary? You could simply have stated the NH was warmer during the HCO. Polar bears are adaptable. They have already started moving south, and at least one polar bear/brown bear hybrid has been found in the wild. The problem is that "south" really means "closer to human settlements." Polar bears, the largest land carnivore currently in existence, are fearless, dangerous animals. How exactly is an increase in polar bear/human interactions a good thing? Incidentally, that's also the reason you mistakenly believe polar bear populations have been increasing, when actual research tends to show a decline: locals are seeing more polar bears, prompting some to say the numbers have increased, when in reality they're simply moving south to find food. You also miss the larger point. The fact that polar bears are leaving their natural habitat is a strong indication of the type of disruptive migratory patterns AGW is causing. As such, it is one more piece of evidence supporting AGW theory, the same theory you constantly (and unsuccessfully) try to undermine. See how I countered your argument without the need for a big unnecessary graph (which, BTW, climatewatcher already used on another thread)?

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