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Can animals and plants adapt to global warming?

Posted on 29 April 2008 by Barry Brook

Guest post by Barry Brook, Director of the Research Institute for Climate Change and Sustainability at the University of Adelaide. Read more at Brave New Climate.

Human are transforming the global environmental. Great swathes of temperate forest in Europe, Asia and North America have been cleared over the past few centuries for agriculture, timber and urban development. Tropical forests are now on the front line. Human-assisted species invasions of pests, competitors and predators are rising exponentially, and over-exploitation of fisheries, and forest animals for bush meat, to the point of collapse, continues to be the rule rather than the exception.

Driving this has been a six-fold expansion of the human population since 1800 and a 50-fold increase in the size of the global economy. The great modern human enterprise was built on exploitation of the natural environment. Today, up to 83% of the Earth’s land area is under direct human influence and we entirely dominate 36% of the bioproductive surface. Up to half the world’s freshwater runoff is now captured for human use. More nitrogen is now converted into reactive forms by industry than all by all the planet’s natural processes and our industrial and agricultural processes are causing a continual build-up of long-lived greenhouse gases to levels unprecedented in at least the last 800,000 years and possibly much longer.

Clearly, this planet-wide domination by human society will have implications for biological diversity. Indeed, a recent review on the topic, the 2005 Millennium Ecosystem Assessment report (an environmental report of similar scale to the Intergovernmental Panel on Climate Change Assessment Reports), drew some bleak conclusions – 60% of the world’s ecosystems are now degraded and the extinction rate is now 100 to 1000 times higher than the “background” rate of long spans of geological time. For instance, a study I conducted in 2003 showed that up to 42% of species in the Southeast Asian region could be consigned to extinction by the year 2100 due to deforestation and habitat fragmentation alone.


Figure 1: Southeast Asian extinctions projected due to habitat loss (source: Sodhi, N. S., Koh, L. P., Brook, B. W. & Ng, P. K. L. 2004)

Given these existing pressures and upheavals, it is a reasonable question to ask whether global warming will make any further meaningful contribution to this mess. Some, such as the sceptics S. Fred Singer and Dennis Avery, see no danger at all, maintaining that a warmer planet will be beneficial for mankind and other species on the planet and that “corals, trees, birds, mammals, and butterflies are adapting well to the routine reality of changing climate”. Also, although climate change is a concern for conservation biologists, it is not the focus for most researchers (at present), largely I think because of the severity and immediacy of the damage caused by other threats.

Global warming to date has certainly affected species’ geographical distributional ranges and the timing of breeding, migration, flowering, and so on. But extrapolating these observed impacts to predictions of future extinction risk is challenging. The most well known study to date, by a team from the UK, estimated that 18 and 35% of plant and animal species will be committed to extinction by 2050 due to climate change. This study, which used a simple approach of estimating changes in species geographical ranges after fitting to current bioclimatic conditions, caused a flurry of debate. Some argued that it was overly optimistic or too uncertain because it left out most ecological detail, while others said it was possibly overly pessimistic, based on what we know from species responses and apparent resilience to previous climate change in the fossil record – see below.

A large number of ancient mass extinction events have indeed been strongly linked to global climate change, including the most sweeping die-off that ended the Palaeozoic Era, 250 million years ago and the somewhat less cataclysmic, but still damaging, Palaeocene–Eocene Thermal Maximum, 55 million years ago. Yet in the more recent past, during the Quaternary glacial cycles spanning the last million years, there were apparently few climate-related extinctions. This curious paradox of few ice age extinctions even has a name – it is called ‘the Quaternary Conundrum’.

Over that time, the globally averaged temperature difference between the depth of an ice age and a warm interglacial period was 4 to 6°C – comparable to that predicted for the coming century due to anthropogenic global warming under the fossil-fuel-intensive, business-as-usual scenario. Most species appear to have persisted across these multiple glacial–interglacial cycles. This can be inferred from the fossil record, and from genetic evidence in modern species. In Europe and North America, populations shifted ranges southwards as the great northern hemisphere ice sheets advanced, and reinvaded northern realms when the glaciers retreated. Some species may have also persisted in locally favourable regions that were otherwise isolated within the tundra and ice-strewn landscapes. In Australia, a recently discovered cave site has shown that large-bodied mammals (‘megafauna’) were able to persist even in the arid landscape of the Nullarbor in conditions similar to now.

However, although the geological record is essential for understanding how species respond to natural climate change, there are a number of reasons why future impacts on biodiversity will be particularly severe:

A) Human-induced warming is already rapid and is expected to further accelerate. The IPCC storyline scenarios such as A1FI and A2 imply a rate of warming of 0.2 to 0.6°C per decade. By comparison, the average change from 15 to 7 thousand years ago was ~0.005°C per decade, although this was occasionally punctuated by short-lived (and possibly regional-scale) abrupt climatic jolts, such as the Younger Dryas, Dansgaard-Oeschger and Heinrich events.

B) A low-range optimistic estimate of 2°C of 21st century warming will shift the Earth’s global mean surface temperature into conditions which have not existed since the middle Pliocene, 3 million years ago. More than 4°C of atmospheric heating will take the planet’s climate back, within a century, to the largely ice-free world that existed prior to about 35 million years ago. The average ‘species’ lifetime’ is only 1 to 3 million years. So it is quite possible that in the comparative geological instant of a century, planetary conditions will be transformed to a state unlike anything that most of the world’s modern species have encountered.

C) As noted above, it is critical to understand that ecosystems in the 21st century start from an already massively ‘shifted baseline’ and so have lost resilience. Most habitats are already degraded and their populations depleted, to a lesser or greater extent, by past human activities. For millennia our impacts have been localised although often severe, but during the last few centuries we have unleashed physical and biological transformations on a global scale. In this context, synergies (positive or self-reinforcing feedbacks) from global warming, ocean acidification, habitat loss, habitat fragmentation, invasive species, chemical pollution (Figure 2) are likely lead to cascading extinctions. For instance, over-harvest, habitat loss and changed fire regimes will likely enhance the direct impacts of climate change and make it difficult for species to move to undamaged areas or to maintain a ‘buffer’ population size. One threat reinforces the other, or multiple impacts play off on each other, which makes the overall impact far greater than if each individual threats occurred in isolation (Brook et al 2008).


Figure 2: Figure from the Millennium Ecosystem Assessment

D) Past adaptation to climate change by species was mainly through shifting their geographic range to higher or lower latitudes (depending on whether the climate was warming or cooling), or up and down mountain slopes. There were also evolutionary responses – individuals that were most tolerant to new conditions survived and so made future generations more intrinsically resilient. Now, because of points A to C described above, this type of adaptation will, in most cases, simple not be possible or will be inadequate to cope. Global change is simply too pervasive and occurring too rapidly. Time’s up and there is nowhere for species to run or hide.

Professor Barry Brook is an international research leader in global ecology and conservation biology. He holds the Foundation Sir Hubert Wilkins Chair of Climate Change and is Director of the Research Institute for Climate Change and Sustainability at the University of Adelaide. He has published two books and over 120 scientific papers on various aspects of human impacts on the natural environment and biodiversity, including climate change, deforestation and overexploitation of populations. In 2006, he was awarded both the Australian Academy of Science Fenner Medal for distinguished research in biology and the Edgeworth David Medal by the Royal Society of New South Wales, and in 2007, the H.G. Andrewartha Medal by the Royal Society of South Australia and was listed by Cosmos as one of Australia's top 10 young scientists. The principal motivation for his research is to identify ways and means of reducing extinctions and mitigating the worst ravages of global change.

Brook, BW et al. 2008. Synergies among extinction drivers under global change. Trends in Ecology and Evolution, in press (email: barry.brook@adelaide.edu.au for a preprint)

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Comments 51 to 66 out of 66:

  1. Re # 48 [chris said: "We know things are going to become increasingly problematic in a warming world"] [Quietman replied: "Not! Again assumption based on a hypothesis. Just because a belief is accepted does not make it true, it's like saying God did it."] No. It's not an "assumption based on a hypothesis"...it's a conclusion based on the evidence. If we don't address the evidence we're in trouble. We can't address future consequences by ignoring the evidence and putting our money on things that we know not to be true.
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  2. Re #49: It's encouraging that you consider that we should address the acidification of the oceans. However fertilizer runoff makes a trivial contribution to ocean acidification, although it does have seriously degrading effects on streams and rivers, and can cause largescale esturial deadzones as a result of promotion of seasonal algal blooms followed by de-oxygenation (e.g. see seasonal de-oxygenation around Chesapeake Bay and the Mississippi delta in the Gulf of Mexico). What is causing the accelerating acidification of the worlds oceans? It's our CO2 emissions Quietman. Around 40-50% of our CO2 emissions are absorbed by the oceans, and this humungous amount is causing the oceans to acidify [CO2 + H2O <-----> H2CO3 <------> HCO3- + H+ <----> CO32- + H+; remember that H+ is acid] Try: Feely, RA et al (2004) "Impact of anthropogenic CO2 on the CaCO3 system in the oceans" Science 305, 362-366. Abstract: "Rising atmospheric carbon dioxide (CO2) concentrations over the past two centuries have led to greater CO2 uptake by the oceans. This acidification process has changed the saturation state of the oceans with respect to calcium carbonate (CaCO3) particles. Here we estimate the in situ CaCO3 dissolution rates for the global oceans from total alkalinity and chlorofluorocarbon data, and we also discuss the future impacts of anthropogenic CO2 on CaCO3 shell forming species. CaCO3 dissolution rates, ranging from 0.003 to 1.2 micromoles per kilogram per year, are observed beginning near the aragonite saturation horizon. The total water column CaCO3 dissolution rate for the global oceans is approximately 0.5 +/- 0.2 petagrams of CaCO3-C per year, which is approximately 45 to 65% of the export production of CaCO3." Sabine, CL et al. (2004) "The oceanic sink for anthropogenic CO2" Science 305, 367-371. "Using inorganic carbon measurements from an international survey effort in the 1990s and a tracer-based separation technique, we estimate a global oceanic anthropogenic carbon dioxide (CO2) sink for the period from 1800 to 1994 of 118 +/- 19 petagrams of carbon. The oceanic sink accounts for similar to48% of the total fossil-fuel and cement-manufacturing emissions, implying that the terrestrial biosphere was a net source of CO2 to the atmosphere of about 39 +/- 28 petagrams of carbon for this period. The current fraction of total anthropogenic CO2 emissions stored in the ocean appears to be about one-third of the long-term potential." The effects of this acidification on oceanic life is reviewed recently here and is rather relevant to the subject of this thread: Hoegh-Guldberg O et al. (2007) "Coral reefs under rapid climate change and ocean acidification" Science 318, 1737-1742. Abstract: "Atmospheric carbon dioxide concentration is expected to exceed 500 parts per million and global temperatures to rise by at least 2 degrees C by 2050 to 2100, values that significantly exceed those of at least the past 420,000 years during which most extant marine organisms evolved. Under conditions expected in the 21st century, global warming and ocean acidification will compromise carbonate accretion, with corals becoming increasingly rare on reef systems. The result will be less diverse reef communities and carbonate reef structures that fail to be maintained. Climate change also exacerbates local stresses from declining water quality and overexploitation of key species, driving reefs increasingly toward the tipping point for functional collapse. This review presents future scenarios for coral reefs that predict increasingly serious consequences for reef- associated fisheries, tourism, coastal protection, and people. As the International Year of the Reef 2008 begins, scaled- up management intervention and decisive action on global emissions are required if the loss of coral- dominated ecosystems is to be avoided. " The oceans will gradually lose their ability to absorb large fractions of our emissions and atmospheric greenhouse gas levels will be enhanced as a result. Already there is evidence that this effect is beginning to be apparent: Le Quere C et al (2007) "Saturation of the Southern Ocean CO2 sink due to recent climate change" 316, 1735-1738. Abstract: "Based on observed atmospheric carbon dioxide (CO2) concentration and an inverse method, we estimate that the Southern Ocean sink of CO2 has weakened between 1981 and 2004 by 0.08 petagrams of carbon per year per decade relative to the trend expected from the large increase in atmospheric CO2. We attribute this weakening to the observed increase in Southern Ocean winds resulting from human activities, which is projected to continue in the future. Consequences include a reduction of the efficiency of the Southern Ocean sink of CO2 in the short term (about 25 years) and possibly a higher level of stabilization of atmospheric CO2 on a multicentury time scale."
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  3. chris Evolution and extinction go hand in hand, I never changed the subject. As to the rest of your comment I have no idea what you are talking about. On my "untruth", Green house is a known effect in a closed system, an unknown in an open system, if more than a hypothesis in an open system then prove it. A theory requires proof, not consensus. Show me the physical evidence that it works they way you indicate.
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  4. Re #53 Quietman I'm afraid that's nonsense. Making stuff up and telling untruths is not skepticism. On untruth: I cited some papers on the relationship between paleodata identifying cold (warm) spells in the deep past and data that identified contemporaneous lowered (raised) atmospheric CO2 levels. You make the ill-informed assertion (your post #43) that "The cited papers assumes that the sensitivity is as the IPCC hypothesizes." But of course they do nothing of the sort, as simple perusal of the papers would establish. Even 'though you clearly have no idea what you are talking about with respect to this work you chose to pursue that falsehood in your post #47. What is to be gained by making up stuff that simply isn't true Quietman? If pursuing an agenda position requires you to misrepresent the work of others, perhaps you should consider whether your agenda position is worth it! On your odd comments about the greenhouse effect: It really does seem that you don't believe in the greenhouse effect, which is rather astonishing. Your schoolboy notions about “open” and “closed” systems are rather dismal (happily a schoolboy would be unlikely to pursue such a level of ignorance!). Is the earth an open or a closed system Quietman? If not, what might a closed system encompass with respect to the solar system, for example? And why would anyone possibly attempt to pursue the notion that an obvious, well-characterized and undeniable phenomenon doesn’t exactly exist by using fallacious arguments based on semantics? In fact the solar system might be considered a closed system, and one could then ponder the distribution of the thermal energy arising from the powerhouse that sits at its “centre”. What happens to all that radiated heat, blasted into the sun’s surrounds in the form of radiation that covers large parts of the visible, UV, and IR regions of the spectrum? How about the earth? We know the size of the sun, its surface temperature, the size of the earth and can estimate a value for the earth’s overall albedo. This allows us to calculate the temperature of a “naked” earth bathed in the solar radiation. This was first done by Fournier in the early 19th century. The earth should be around 255K (-18 oC). We can do the same calculation now. Same result. We know this simple analysis is effective since we can apply it to other planets and determine their “black body” temperature. Spectroscopic analysis of the true planetary temperature is revealing of its atmospheric composition, and we can explore this further using spectroscopic detection of the atmospheric gases. So why is the earth so warm (a cozy ~288 K)? Already in the 19th century that was identified. It’s our atmospheric water vapour and carbon dioxide. These molecules (unlike the symmetric O2 and N2 that make up the vast proportion of our atmosphere) absorb infra-red radiation emitted from the earth following insolation, and reradiate the energy (or “bump” into surrounding atmospheric gas molecules increasing their kinetic energy, which, as you should know, is effectively equivalent to their “temperature”). How do we know that CO2 and water vapour absorb and re-radiate infra-red radiation? Because we can measure it directly. It’s a no-brainer Quietman. The greenhouse effect exists. The question then relates to the amount that the greenhouse efect warms us (e.g. the "climate sensitivity"). Since we know the infra-red absorptive properties of CO2 (and water vapour) we can calculate the radiative forcing that results in increasing the atmospheric CO2 concentration, for example. This forcing results in the retention of excess thermal energy by the suppression of the ability of surface infra-red to radiate freely into space. It’s a little like lying in your chilly bed in February, and putting a blanket on top of you. Is that a “closed system” Quietman? Not really. And yet you get warmer (else you’d probably not bother). The suppression of the escape of radiation into the surrounds (your bedroom or cold empty space) results in a shift in the equilibrium temperature of the surface of the body “protected” by the thermal “blanket” to a higher value. The full effect of raising atmospheric CO2 levels on the earth’s temperature is realized by feedbacks. The most important one is the rise in atmospheric water vapour concentrations as the atmosphere warms under the influence of enhanced CO2. Does this increase in atmospheric water vapour in the atmosphere actually occur? Yes it does Quietman. How do we know? Because we can measure it. And so on.
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  5. Re #53 Quietman, it’s worth highlighting the essential difference between your (and Mizimi’s, apparently) and my view on extinctions in relation to global warming. I’ll outline this again, since according to your post #53 you don’t seem to understand what I am talking about. Both you and Mizimi dissociate yourself from the situation as it stands, discount the possibility that we might consider our role in potential species extinctions and what the consequences might be for our and our near descendents welfare, and consider this from the point of view of a rather carefree observer. Your attitudes are similar in nature to those that might enter a discussion on the steps we might take to reduce deaths from automobile accidents, by pointing out that it’s in the very nature of things that collide at high speeds that they become deformed from impacts, but that this is just a general law of physics, and we might actually find it “interesting” to observe these dispassionately. It’s difficult to come to any other conclusion based on your continual turning of the subject of this thread towards rather “potted” concepts of evolutionary "theory". You (and Mizimi) consider the situation to be “natural”, that things are just following “ the rule in evolution”, “evolution must take it’s course” and so on. Your comments in particular are extraordinary, since you seem to consider “extinction cycles” rather excellent, to the point of cheerleading for an extinction. And yet you seem oblivious to the evidence that (i) major extinction events are actually not that wonderful in practice to those involved and (ii) that the “interesting” consequences that you envisage take many hundreds of thousands or millions of years. Since the concerns of mature and far-sighted individuals is for the immediate future (the several decades to come), extending possibly towards events that might be set in motion now to impact our descendants of the coming century or two, it seems astonishing that someone would consider that it will be rather excellent to pursue a relatively near future of large scale extinction in the cerebral delight of considering what a wonderful evolutionary recovery might accrue a million years from now. A rather apocalyptic vision, in fact. There are surely some rational skeptical viewpoints with respect to the expectation of wide-scale warming-induced extinctions resulting from man-made enhancement of the earth’s greenhouse effect. One might have the view either that it’s not really warming (difficult to defend), that it won’t warm that much in the future (likewise difficult to defend, ‘though pretending that the greenhouse effect doesn’t exist certainly helps!), or that the warming won’t actually be a problem for species on a wide scale. In my opinion none of these is a comforting possibility when considered in the light of the evidence in the real world either as it exists now, or from paleo-analysis of events in the deep past. But the notion that we wash our hands of the entire business, and pursue self-defeating scenarios without consideration of their consequences, other than in the light of a cerebral interest in extinctions (one of your “favorite studies”), seems extraordinarily perverse if not downright repellent…
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  6. #46....Abstract: "Atmospheric carbon dioxide concentration is expected to exceed 500 parts per million and global temperatures to rise by at least 2 degrees C by 2050 to 2100," et seq.posts. One major problem the AGW argument has ( and one of the primary reasons I remain sanguine about the whole affair) is that of time. They seem to assume that there are endless supplies of fossil fuels just waiting to be used, and then make forward projections on that assumption. Recoverable coal reserves are currently estimated at 147 years supply based on current consumption. Oil production has peaked and estimated reserves = 40 years supply. Natural gas estimated reserves = 65 years. ( not including clathrates). So the likely future for my grandchildren ( who may live to see 2100, some 92 years away) is one of energy poverty - and potential devastating decline in civilisation (accelerated by 'energy wars'). So the most likely candidate for an extinction event is "Homo Sapiens Civilis" http://www.worldcoal.org/pages/content/index.asp?PageID=188 http://www.eia.doe.gov/emeu/international/reserves.html http://www.eia.doe.gov/basics/quickoil.html
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  7. Re #56 That's not really true Mizimi and your argument has a self-defeating element to it. ONE: If one addresses the fossil fuel reserves in relation to estimated recoverable sources rather than proven reserves (the values of which continually increase as new reserves are found), there is a whole lot more fossil fuel with potential for mining. Atmospheric CO2 levels can go way higher than 500 ppm. The US department of energy (DOE) estimate, that the proved[***] reserves for oil and gas are: 1.14-1.33 trillion barrels of oil (equivalent to around 43 years worth) 6.2-6.4 trillion cubic feet of natural gas (equivalent to around 160 years worth) and estimated recoverable coal (anthracite, bituminous, lignite and subbituminous): 1 million, million short tons of coal (equivalent to more than 400 years worth). oil and gas (Aug 27th 2008 update): http://www.eia.doe.gov/emeu/international/reserves.xls coal: http://www.eia.doe.gov/pub/international/iea2005/table82.xls [***] Proved reserves are estimated quantities that analysis of geologic and engineering data demonstrates with reasonable certainty are recoverable under existing economic and operating conditions. Burning all of that fossil fuel will take atmospheric CO2 levels way, way above 500 ppm. We're talking more like 1200-1500 ppm TWO: the obvious solution. Your approach to this is extraordinary. You're seemingly totally accepting of widescale extinction (you and Quietman consider this is just "natural")...you suggest that the "likely future for" your "grandchildren is one of energy poverty" and that "the most likely candidate for an extinction event is "Homo Sapiens Civilis""...and yet you consider that it's worthwhile propagandising against the science that might (and is, happily) help us in addressing these rather obvious problems. There is a solution to your grandchildrens "energy poverty" and your suggestion of "Homo Sapiens Civilis potential "extinction" (you suggest they're the "most likely candidate"). It's to address the problem with a bit of maturity and rationality. We take sequential steps towards switching our energy supplies towards the sustainable supplies that are clearly the only possible future of mankind. However difficult that may be, it solves all of the problems highlighted. Your grandchildren escape "energy poverty"...your "Homo Sapiens Civilis" escape "extinction"....the natural world avoids a wide-scale extinction (see top post by Barry Brook)...our descendants avoid massive, debilitating, and extraordinarily costly sea level rise...ocean acidification....enhanced drought in the central latitudes...enhanced extreme weather events....irrigation supply catastrophes and so on.... I have a feeling we might all be somewhere approaching the same wavelength on this!
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  8. chris Of course, how could I have been so stupid as not to see the light. Amen.
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  9. Mizimi Jast an FYI: Global synchronous changes in the carbon isotopic composition of carbonate sediments unrelated to changes in the global carbon cycle Peter K. Swart Department of Marine Geology and Geophysics, Rosenstiel School of Marine and Atmospheric Science, University of Miami, 4600 Rickenbacker Causeway, Miami, FL 33149 Edited by John M. Hayes, Woods Hole Oceanographic Institution, Woods Hole, MA, and approved July 24, 2008 (received for review April 15, 2008) Abstract The carbon isotopic (δ13C) composition of bulk carbonate sediments deposited off the margins of four carbonate platforms/ramp systems (Bahamas, Maldives, Queensland Plateau, and Great Australian Bight) show synchronous changes over the past 0 to 10 million years. However, these variations are different from the established global pattern in the δ13C measured in the open oceans over the same time period. For example, from 10 Ma to the present, the δ13C of open oceanic carbonate has decreased, whereas platform margin sediments analyzed here show an increase. It is suggested that the δ13C patterns in the marginal platform deposits are produced through admixing of aragonite-rich sediments, which have relatively positive δ13C values, with pelagic materials, which have lower δ13C values. As the more isotopically positive shallow-water carbonate sediments are only produced when the platforms are flooded, there is a connection between changes in global sea level and the δ13C of sediments in marginal settings. These data indicate that globally synchronous changes in δ13C can take place that are completely unrelated to variations in the global carbon cycle. Fluctuations in the δ13C of carbonate sediments measured during previous geological periods may also be subject to similar processes, and global synchroniety of δ13C can no longer necessarily be considered an indicator that such changes are related to, or caused by, variations in the burial of organic carbon. Inferences regarding the interpretation of changes in the cycling of organic carbon derived from δ13C records should be reconsidered in light of the findings presented here.
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  10. Re #58 that's excellent Quietman. One should always strive for truthful exposition... ..and the greenhouse effect really isn't difficult to comprehend..
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  11. "We take sequential steps towards switching our energy supplies towards the sustainable supplies that are clearly the only possible future of mankind." Totally agree: As I stated in another thread it is imperative we shift away from fossil fuels (and long term nuclear power) NOT because it will reduce CO2 emissions but because these fuels are finite. So we agree on that. That it also has the added effect of reducing CO2 emissions is a bonus (maybe).
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  12. QM: #59...thanks, very interesting. I have always regarded paleo-data as indicative of trends rather than absolutes because there seemed to be too many other factors that could influence the results that cannot be 'pinned down' with any exactitude. Now it seems the basis for one proxy is suspect; how many others might also be compromised?
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  13. Mizimi Well, that paper *and any other paper, is an argument. The authors interpretation of his/her research, and as such is hypothetical. But I did find it interesting and as it relates to our prior discussions, thought you might find it of interest.
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  14. FYI; The sea of Cortes, off the coast of California, has been seriously overfished for many years, resulting in the loss of predators for the Humboldt squid. Because of this, and the squid's own predatory nature, its population has 'explode' to an estimated 20million+. (Much dismay and gnashing of teeth amongst marine biologists) However, the Right whale, which uses this sea as a stopover on its annual migration considers this squid as a great delicacy...as a result, Right whale numbers are increasing...........serendipity? Or 'nature' doing a balancing act?
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  15. Chris: Whether an extinction of a species is 'good' or 'bad' really depends on whether it's you or not, in other words, on your personal perspective. From a world view, the best thing might just be the extinction of Homo Sapiens Civilis!
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  16. Ps: Chris; I am not 'propagandising' against the science that 'might' find a solution to this problem. I am unconvinced that the 'problem' exists in the magnitude that is being proposed, especially since the 'science' is currently incapable of modelling what is going on to a reasonable degree of accuracy. In addition, the GMT ( which is actually a mathematical artefact and does not exist) 'record' indicates a rise of less than 2C by the end of this century. Hardly enough to cause panic attacks. Not only that, but I am skeptical that a)the root of the problem is just CO2 from fossil fuels and b)that even if it was, the chances of getting global action to reduce FF usage are pretty slim ( politicians being what they are). We already have countries pulling out of or ignoring agreements to reduce emissions ( The US, Canada, Australia to name but three, one of which is the biggest consumer...guess which) so either they don't care OR they know something we don't.
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