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Doug Bostrom at 07:12 AM on 18 May 2010Increasing CO2 has little to no effect
Babelsguy, your friend apparently has not so much a quibble with C02 as a GHG so much as he does with the concept of an atmosphere being able to trap heat. After all, what he believes applies to any GHG. How does he explain why Earth's climate is not the same as that of a planet with no atmosphere? -
Steven Sullivan at 07:11 AM on 18 May 2010It's cooling
Oh joy, we're about to get another revival of this argument http://climatedepot.com/a/6574/search.asp?cx=partner-pub-2896112664106093%3Am5ewh74pu5c&cof=FORID%3A9&ie=ISO-8859-1&q=global+cooling "Geologist Declares 'global warming is over' -- Warns U.S. Climate Conference of 'Looming Threat of Global Cooling' " -
babelsguy at 05:08 AM on 18 May 2010Increasing CO2 has little to no effect
A related question about the basics of the greenhouse effect: I have been sent a "study" by a guy who claims that CO2 cannot be a greenhouse gas because any warming would cause an instant increase in outward radiation due to the increased temperature difference between the atmosphere and open space, which would immediately diminish the warming. I tried to discuss some sense into him, but in classic denier fashion, he remained stubborn that nobody so far could give him a "convincing" reason why his objection cannot be true. I tried the earth system's heat capacity, speed of propagation of temperature changes in a kilometer-thick atmosphere, dynamic equilibrium, I even quoted the paragraphs from "A History of Global Warming" at aip.org that say that the actual greenhouse effect is caused by a greenhouse gas concentration change at the tropopause, effectively shifting it into higher, cooler layers of the atmosphere, which radiate heat less effectively than warmer layers, which forces the whole of the temperature gradient in the atmosphere to do something like a parallel shift in order to achieve a high enough temperature at the tropopause to force enough radiation out into space to re-establish the equilibrium - all to no avail. What would you experts here tell him (assuming he might still be convinced)? Any reply very much appreciated! Cheers, babelsguy -
Doug Bostrom at 05:01 AM on 18 May 2010CO2 measurements are suspect
Johnd, surely the same processes you hypothesize in your #25 would apply for 02 as well? -
johnd at 04:04 AM on 18 May 2010CO2 measurements are suspect
doug_bostrom at 03:47 AM, I don't have the appropriate data available, perhaps you will have, what is the proportion of atmospheric oxygen that is involved in exchange processes at the surface, or elsewhere for that matter? -
Doug Bostrom at 03:47 AM on 18 May 2010CO2 measurements are suspect
Johnd, what about other gases? Forgetting C02 for a moment, how about molecular oxygen? Well mixed? Not well mixed? -
johnd at 03:39 AM on 18 May 2010CO2 measurements are suspect
What would be the means that allows CO2 to be well mixed in the atmosphere whereas heat is not. Heat content varies from one extreme to the other not only with altitude but across all the regions of the world. One would expect that whatever mechanism controls the transportation of CO2 would also be involved in the transportation of heat. Given that the amount of CO2 that is pumped into the atmosphere by the combustion of fossil fuels is very small compared to the quantity of CO2 that is in constant exchange between the atmosphere and the surface, about 1/60th, either the concentration of CO2 will be higher right at the surface where the exchange takes place or there are very violent forces in place that if able to transport and distribute the CO2 given up by the plants, soil and oceans has to be matched by perhaps even greater violent forces that has to search the entire atmosphere and gather the CO2 up to concentrate it and physically transport it back to the surface, all without doing the same to the heat contained in the environments that well mixed CO2 would find itself. Either that or the CO2 exchanged through natural processes stays very close to the surface. It is very clear how the local CO2 levels vary considerably during the plant growing seasons around the world which generally coincide with more stable and benign weather systems, and also from the experiences of decades of CO2 enrichment experience in the greenhouse industry producing plants and food, where CO2 levels can vary considerably within each greenhouse itself requiring forced circulation that not only ensures that the required levels of CO2 are evenly distributed to the plants, but also the heat, and one cannot be redistributed without the other. -
Martin at 03:39 AM on 18 May 2010Woody Guthrie award to The Science of Doom
Just had a look. Excellent! BTW I was reading his post on "Models, On – and Off – the Catwalk – Part Two". The last comments are an exchange about what consitutes V&V (Verification and Validation) in a climate model. I'm not an expert. I've just got the feeling that climate models can't be quite as bad as one commentor puts it even if they haven't been validated in the same way as Boeing’s computer models of airplanes. Do you have a view on this issue? -
tobyjoyce at 03:27 AM on 18 May 2010Woody Guthrie award to The Science of Doom
Great blog. We needed a site that explained the mathematics and physics of global warming. I know there are some, but this is the best I have seen so far. -
thefrogstar at 03:18 AM on 18 May 2010Woody Guthrie award to The Science of Doom
Many thanks. Good choice. I've just visited the SoD site for the first time. It appears excellent. -
Phila at 02:44 AM on 18 May 2010Species extinctions happening before our eyes
#50 Arkadiusz Semczyszak "In the nineteenth century, glaciers in the Alps were moving at a speed of (locally) up to 3-4 meters per day in one (...) destroying entire ecosystems." Statements like this would be more useful if you provided a cite, and some sort of context. Better formatting might also help to make your arguments more intelligible. As for your quote from Lonnie G. Thompson, it seems safe to say that Dr. Thompson draws very different conclusions from his life's work than you do. von Gunten et al. (2009) -
chris at 01:59 AM on 18 May 2010Species extinctions happening before our eyes
Arkadiusz If it's "high time to abandon the Mann hockey stick" then why do you guys keep obsessing about it?...and if as you say "Since 1998 science has changed" why do you ignore the wealth of data on this subject from the last 6 or 7 years, and continually hark back to 12 year old papers? In fact no one talks very much about Mann et al 1998/1999 these days (although the data continues to be displayed in reviews on the subject that covers the entire paleoreconstruction field). After all this is 12 year old research and there have been numerous paleoreconstructions in the intervening years. These all yield pretty much the same conclusions about Northern hemisphere temperature as originally presented all those years ago. You can find them all in the NOAA repository of paleoreconstructions. I don't think any of them show what you suggest (what data are you referring to in your post?). I've had a quick look at the following reconstructions [***] (URL's available on request) and none of them show the odd features (periods warmer than 20th century between AD 1150 and 1350 and "sharp drops between AD 1350 and 1400". In fact none of them show maximum temperatures in the NH of the last 2000 years greater than the mid-20th century global average, and most of the published paleoreconstructions show temperature rises during the period AD 1350-1400. So what have you been looking at??? [***] D. S. Kaufman et al. (2009) Recent Warming Reverses Long-Term Arctic Cooling Science 325, 1236-1239 M. E. Mann et al (2008) “Proxy-based reconstructions of hemispheric and global surface temperature variations over the past two millennia” Proceedings of the Natl. Acad. Sci. USA 105:13252-13257 Lee TCK, Zwiers FW, Tsao M (2008) “Evaluation of proxy-based millennial reconstruction methods.” Clim Dyn 31:263–281. Hegerl GC et al (2007) “Detection of human influence on a new, validated 1500 year temperature reconstruction.” J Clim 20:650–666. D'Arrigo RD, Wilson R, Jacoby G (2006) “On the long-term context for 20th century warming.” J Geophys Res 111:D03103. Viau, AE et al (2006) “Millennial-scale temperature variations in North America during the Holocene” J. Geophys. Res. 111, D09102. Moberg, A. et al. (2005) Highly variable Northern Hemisphere temperatures reconstructed from low- and high-resolution proxy data. Nature 433, 613-617 dfjdkh -
Ned at 01:38 AM on 18 May 2010CO2 measurements are suspect
Johno writes: Satellites are beginning to debunk the idea that CO2 is "well-mixed" in the atmosphere. More data is needed, but the early indications prove Chris is out on a limb when assuming such an unfounded idea. Did you see the video linked above, which shows a year of satellite data? Note the scale at the bottom. Over the entire year and the entire globe, CO2 ranges from ~375 to ~390 ppmv. That's pretty well mixed, IMHO. -
hammiesink at 01:12 AM on 18 May 2010There is no consensus
Poptech, Science is decided by evidence, not signers of petitions. The reason almost all major scientific institutions agree with the mainstream view of global warming is because the scientific evidence overwhelmingly supports it. Notice the consistency on one side of the debate: CO2 is rising, leading to warmer temperatures and a potentially serious problem that should be mitigated. Compare to the inconsistency on the skeptic side: it's not warming, it is warming but it's the sun, it's not warming, it is warming but it's el nino, CO2 is causing warming but climate sensitivity is low, it's cooling, it's warming but it's cosmic rays, it's warming and it's CO2 but cap and trade sucks, the hockey stick has been debunked, it's cooling, it's warming but it's water vapor, it's cooling because of the sun, it's a statistical mistake, it's warming, it's cooling. Is that about it? Did I succinctly summarize the "skeptic" position correctly? -
Alexandre at 00:29 AM on 18 May 2010Woody Guthrie award to The Science of Doom
I'm a regular visitor to the Science of Doom blog. I've learned a lot about the basics of the physics involved, and he's usually available to answer directly to my amateur questions. Now I have the selfish feeling that he'll get more known and visited and won't be that available anymore... He deserves it. Good choice. PS: For new visitors, I would suggest to take some time and read the CO2 series from the beginning. It's well worth it. If you want to have an opinion about something, you must understand it first. -
sylas at 00:24 AM on 18 May 2010Woody Guthrie award to The Science of Doom
I discovered science of doom quite recently, and was enormously impressed. Well chosen indeed. -
Arkadiusz Semczyszak at 23:59 PM on 17 May 2010Species extinctions happening before our eyes
Marcus "... quantitative evidence for the presence of a Medieval Climate Anomaly (in this case, warm summers between AD 1150 and 1350; ΔT = +0.27 to +0.37°C with respect to (wrt) twentieth century) and a very cool period synchronous to the 'Little Ice Age' starting with a sharp drop between AD 1350 and AD 1400 (-0.3°C/10 years, decadal trend)... [!!!]" (2009). The present warming (last 50 years in the twentieth century) is not even half of that ... In the nineteenth century, glaciers in the Alps were moving at a speed of (locally) up to 3-4 meters per day in one (...) destroying entire ecosystems. Marcus - high time to abandon the Mann hockey stick ... Since 1998, science has changed ... Even the IPCC has said that the former does not change the temperatures were in the hundreds and thousands of years - L. Thompson - IPCC - "This abrupt event, ≈5,200 yr ago, was widespread and spatially coherent through much of the tropics and was coincident with structural changes in several civilizations. These three lines of evidence argue that the present warming and associated glacier retreat are unprecedented in some areas for at least 5,200 yr." ... and so I could enumerate dozens, dozens of works from the last years. Natural strong climate change is likely always been sudden. -
JMurphy at 23:54 PM on 17 May 2010Climate Change and the Integrity of Science: a letter to Science
neilperth, you answered your question by the examples in your second paragraph - even though we all know what the problems are, we won't do anything about it until it affects us personally and directly. You could also see the inaction from politicians before the credit crunch, even though many economists, etc. had been predicting it and we were all just basically waiting for it to happen. I'm not sure how much of a threat comes from an increase in human population, though - as long as there is enough food, water, work, etc. The main threat will be the way climate change impacts on that food, water, work, etc. -
Johno at 23:28 PM on 17 May 2010CO2 measurements are suspect
Satellites are beginning to debunk the idea that CO2 is "well-mixed" in the atmosphere. More data is needed, but the early indications prove Chris is out on a limb when assuming such an unfounded idea. In addition, the argument against taking CO2 readings in cities is clearly specious. Long term CO2 trends should be as readily apparent as long term temperature trends. Of course, the data from cities will be as polluted by urban growth as are temperature records, but the results would still be useful. -
jimalakirti at 22:54 PM on 17 May 2010Woody Guthrie award to The Science of Doom
Science of Doom is a great choice. Thanks for pointing it out.A lot of my readers and I have been looking for an information source just like this. -
Marcus at 22:45 PM on 17 May 2010Species extinctions happening before our eyes
Also, there is plenty of evidence to suggest that rapid methane release-& resultant *warming*-caused the mass extinction at the Permian/Triassic boundary, & a lot of evidence to suggest that the original Cretaceous impact that wiped out the dinosaurs probably led to "rapid" warming, before the planet got cold. So I'd suggest you need to check your facts a bit more carefully in future Arkadiusz. -
Marcus at 22:41 PM on 17 May 2010Species extinctions happening before our eyes
Wrong again Arkadiusz Semczyszak. Take a look at all the temperature proxies for the last 12,000 years & what do you see? I see temperature rises of a similar magnitude to recent warming-but over a period of CENTURIES OR EVEN MILLENIA! By modern day standards, these warming events have actually been incredibly slow. Even in all the previous Interglacial Periods where the planet was moving closer to the sun-& the change in temperature was on the order of 8 to 12 degrees Celsius-it was still occurring over tens of thousands of years (one warming event, 150 kyrs before the present, took 25,000 years for a 10 degree warming to occur-or +0.004 degrees per decade, nearly 20 times *slower* than in the modern age). So please spare us this talk about past warming being "really sharp"-they were actually quite dull compared to everything we're currently doing. Yet if these relatively *slow* warming periods could cause mass extinctions, then what potential for extinction is there in this more rapid warming phase? -
dorlomin at 22:07 PM on 17 May 2010Woody Guthrie award to The Science of Doom
I have been a huge fan of that blog as well. An excellent addition to the blog roll. -
CBDunkerson at 21:44 PM on 17 May 2010Species extinctions happening before our eyes
On the whole 'local extinction is not extinction' bit... actually, this is not always true. There are differing definitions of the word 'species', but most are close to the concept of a breeding population. However, we can't track the breeding habits of every animal in the world and don't really know if two animals from opposite sides of the planet would breed fertile offspring or not. Thus, we generally ASSUME that animals which LOOK alike are members of the same species. Modern genetic science has proved over and over again that this assumption is wrong as often as not. In many cases what we call a 'local population' of a species is, in fact, a DIFFERENT species which looks very similar but has significantly different DNA and cannot interbreed. Read up on cryptic species to see what I'm talking about. Also a news article on a recent example of discovering that such a 'local population' was actually a separate species. Thus we can be quite certain that some of these 'local extinctions' are in fact the TOTAL extinctions of distinct species which had just not been classified as such yet. -
Riccardo at 21:06 PM on 17 May 2010Climate Change and the Integrity of Science: a letter to Science
neilperth, I think this is the realm of sociology. Science tells us what the threat is, societies may choose not to see, at least for a while. This behaviour is not at all new in human history. It makes me think about the famous Asimov's short story Nightfall, definitely worth a reading. -
Arkadiusz Semczyszak at 19:01 PM on 17 May 2010Species extinctions happening before our eyes
"The fossil record shows us that mass extinction events coincided with periods of dramatic climate change." As an environmentalist (dynamic ecology) I have to take a voice. The emergence of human civilization has led to the great extinction (which takes out) by: 1. Sharp reversal of natural ecosystems to agriculture. 2. Habitat fragmentation (anthropogenic barriers hindering migration in the case of climate change - temperature), and depletion of natural environments (the exploitation and pollution). Under these conditions, any even the smallest variation in temperature can lead to the extinction of many species. ... but: 1. Current temperature change is indeed, but not violent. Her "unprecedented" is long-term sustainable growth temperatures. 2. Remember that it is always cool = reduce the number of species - selection, warming = adaptive radiation; ecosystems with the greatest biodiversity is warm ecosystems. Arctic Ecosystems area (the NPP) are often based only on a few species of algae. Indeed it is often (NPP) greater than in the tropics, in tropical al is their (algal species), hundreds ... Interestingly, even the polar bears were created during one of the interglacial’s - allowing the expansion to the north of Grizzly Bear. Conclusion: warming (at current rates) will help considerably larger number of species to survive the current anthropogenic pressures and lead to the elimination of rare species, as a rule, and so are at the end of its "evolutionary road". 3. Studies targeting potential adaptive responses to changes in temperature, are often fragmented and concern over a short period of time (at least claims about the oceans, professor Jean-Pierre Gattuso - Programme Arctic EPOCA). Geological studies are too vague. "For example an assessment of amphibian extinction rates estimates this at more than 200 times the background rate." In particular, insects and amphibians because of their enormous potential reproductive and breeding create a large number of so-called. "ephemeral species". Their "evolutionary life" has always been short (which uses such as Professor Tim Flannery). "Did a large meteorite (as measured by Iridium distributions) cause the mass extinction of the dinosaurs (I'm not sure if this is what is meant by the Permo-Triassic extinction)?" Probably all the great extinctions caused rapid cooling (no warming). The Permo-Triassic extinction - anoxia - is still only a "fashionable" hypothesis ... So what do you need? Instead of spending money to fight AGW, above all, should be used to reduce fragmentation of natural environments. In the past temperature changes were really sharp and I'm sure this will be in the future ... -
Phila at 16:19 PM on 17 May 2010Species extinctions happening before our eyes
The complaints about the term "local extinction" seem to me to be missing the point. The regional loss of a species can have huge repercussions, both for other plants and animals and for humans who rely on them. (It could even have consequences for tourist economies, in some areas.) Re-introducing a species may be possible, depending on how much time has passed, whether the problem that caused the initial extinction has been solved, etc. If AGW is the problem, it could be some time before re-introduction is feasible, to put it mildly. (Which reminds me: One of the stranger tendencies on the "skeptic" side is to claim, often simultaneously, that extinction is perfectly normal, and that a given animal or plant will be fine because it'll simply adapt to AGW. I'm not sure you get to have it both ways.) -
neilperth at 14:37 PM on 17 May 2010Climate Change and the Integrity of Science: a letter to Science
I was thinking the other day............If so called "climate change" is proved and it's adverse effects on us as humans are so obvious,as you imply, why are the world's politicians doing next to nothing about it ? This seems rather odd to me. The human population increase has been a threat to humans for years but again not much is done about it - likewise lack of food and disease in certain areas of the world. -
Ron Crouch at 11:19 AM on 17 May 2010Species extinctions happening before our eyes
Speaking of which: according to the latest United Nations Global Biodiversity Outlook report. Quote:"Noting that the world has failed to meet its target to achieve a significant reduction in the rate of biodiversity loss by 2010, the report stressed that with the current rate of biodiversity loss, there will be “a severe reduction of many essential services” provided by nature to human societies, as ecosystems reach their limit and shift to alternative, less productive states, “from which it may be difficult or impossible to recover.”" -
Don Gisselbeck at 11:10 AM on 17 May 2010Species extinctions happening before our eyes
Aren't humans just about the ultimate weed species? Am I being too optomistic hoping that all we are doing is fighting for the survival of civilization? -
Ron Crouch at 09:24 AM on 17 May 2010Species extinctions happening before our eyes
Migration has it's limits as well. It is well within the realm of possibility that some species will have no place to migrate to and will finally go extinct (some migrations being vertical while others follow a lateral pattern). Some species will go extinct as a result of being displaced by the migration of other species. And let's not forget the other pressures we place upon species through loss of habitat and pollution. Someday we may find ourselves on the "endangered species list". -
chris at 07:40 AM on 17 May 2010Species extinctions happening before our eyes
thefrogstar at 06:41 AM on 17 May, 2010 frogstar, there has apparently been a long standing uncertainty over whether it was the Chicxulub asteroid impact, or an earlier (or later?) impact whose crater hasn't been found (under the sea?), or whether the massive flood basalt eruptions that produced the Deccan Traps in now-India was responsible (or a major contributor; e.g. the Deccan Traps resulted in a long term stressing and the impact delivered the coup de gras). Very recent reassessment of all the data seems to point to the Chicxulub asteroid impact being the cause of the end-Cretaceous extinction that did for the dinosaurs 65 MYA (and set the stage for the wonderful world of mammals!). The Permian-Triassic extinction was 251 MYA and was a particularly brutal mass extinction. -
chris at 07:11 AM on 17 May 2010Species extinctions happening before our eyes
batsvensson at 06:24 AM on 17 May, 2010 sorry, batsvensson; I drifted into British yoof colloquialism! I meant "massive" in the sense of "large". It's not straightforward to determine extinction rates, and these are presumably always estimates (both of the natural background rate and whatever current rate one is attempting to compare). However estimates of current extinction rates put these at 10's to 100's of times the background rate. For example an assessment of amphibian extinction rates estimates this at more than 200 times the background rate. I believe the estimated extinction rates of reptiles are similarly high. M. L. McCallum (2007) Amphibian Decline or Extinction? Current Declines Dwarf Background Extinction Rate J. of Herpetology 41:483-491 -
thefrogstar at 06:41 AM on 17 May 2010Species extinctions happening before our eyes
Yes, John, my bad (#29). CO2 was there in the penultimate sentence. I shouldn't try and do science on a Saturday night. Some of the later posts re-ignite a question I've asked of geologist-friends before, but not got a satisfactory answer to. That is: Did a large meteorite (as measured by Iridium distributions) cause the mass extinction of the dinosaurs (I'm not sure if this is what is meant by the Permo-Triassic extinction)? Or was it something else? I've also read that the extinction occurred over a period of greater than a million years, which doesn't seem much related to a cataclysmic impact of either climate or meteorites. -
batsvensson at 06:24 AM on 17 May 2010Species extinctions happening before our eyes
chris at 23:47 PM on 15 May, 2010 "The reality is that species extinctions are occurring at a massively faster rate than the background extinction rates." I am curious as to what you mean when you say "massively faster rate" above. Is it massively as in mass-extinction rate or some else rate? -
chris at 04:27 AM on 17 May 2010Species extinctions happening before our eyes
my post didn't post properly (???) Here it is again... thingadonta at 15:15 PM on 16 May, 2010 Thingadonta, please read the paper and stop blustering about things unrelated. As the study states explicitly, as does the accompanying commentary and my post you responded to, the areas studied were otherwise intact habitats. So this isn't about ants in your kitchen or koalas in Sydney CBD. It's not about tearing buildings down to reintroduce koalas, nor about "socioeconomic values". And "local extinction" is nothing like "partially pregnant" which is an objectively meaningless term. If you read the paper in the context that the Earth has something like 45% of its land area still in the form of wilderness, then in areas that have rather little local human impact (and some that do) many species of lizards across the 5 continents of the world in many habitats are struggling to cope with the enhanced Spring temperatures in a warming world. In 12% of the habitats, and more so in other regions of the world, many of these lizard species have disappeared from these habitats entirely. They are locally extinct. The common factor is warming. Many animal species are in danger of extinction and many have already gone extinct [*]. Some of these are lizards. Several of the lizard species studied by Sinervo et al are on the Red List of Threatened Species, and the incremental loss from local habitats is a potential harbinger of full extinction, since that scenario has already been played out for other now extinct species. If we are going to understand the nature of contemporary extinctions, their causes and the increasing impacts of global warming then we might as well take the science seriously. ------------------------------- [*] According to this paper "In late 2007, there were 41,415 species on the International Union for Conservation of Nature Red List, of which 16,306 are threatened with extinction; 785 are already extinct." -
Tom Dayton at 01:49 AM on 17 May 2010There's no empirical evidence
John Cook, I suggest that some combination of the contents of Ned's and Riccardo's comments be incorporated in the Is Global Warming Still Happening? post, because the question they are answering arises frequently, and the answer is not intuitively obvious. -
Riccardo at 00:47 AM on 17 May 2010It's not bad
coloursoflife, do you really think that the behaviour during vacations is an appropiate indicator of the overall benefit of a climate over another? I could agree only if you let me stay on paid vacation 365 days a year :) -
Riccardo at 00:37 AM on 17 May 2010There's no empirical evidence
PaulK, a constantly decreasing OLR correspond to a runaway warming. Luckly this is not the case. The behaviour depends on how fast OLR decreases in the CO2 bands with respect to the increase in the thermal background (proportional to T^4). If CO2 concentration increases at a "pathological" high rate you have a countinuous dcrease of the OLR; this is a runaway warming. If you have, at the other extreme, very slow CO2 increases you get a steady state slightly lower than (almost at) the equilibrium value. In the actual case, you have that CO2 concentration started increasing but the increase of the thermal emission is delayed by it's characteristic response time; so initially OLR decreases but sooner or later thermal emission will try to keep up, untill eventually steady state (not equilibrium) is reached at a value, again, lower than equilibrium. The deviation from equilibrium indicates the rate of increase of the CO2 forcing. In the so called zero dimension aproximation of the atmosphere/surface system this behaviour can be easily modeled. It's worth a try. -
Tom Dayton at 23:49 PM on 16 May 2010Species extinctions happening before our eyes
Argus, the scientists chose a sample of sites spanning a range of typical temperatures, and chose multiple sites at each of those typical temperature levels. They inventoried lizards of all species at all those sites. In other words, the scientists were indeed looking for new populations forming elsewhere. As John's post says, "What is being observed is species are relocating to cooler regions in response to warming temperatures. Lizard populations from lower elevations are expanding up to cooler, higher habitats. This appears to be exacerbating extinction of species already living in higher elevations." That means the scientists observed (those are the "facts" you are looking for) new populations in the cooler sites. In other words, the scientists did look for, observe, and report that new populations formed. But each new population competes with the extant population, helping to drive the extant population to extinction. That domino process peters out at the coolest end of the habitat range, where the extant populations tend to just disappear instead of migrate. That's because a habitable zone for lizards must have more than the right temperature. Other animals, and plants, do not migrate at the same pace, and in many cases never do. Cooler sites also tend to be higher altitude sites, entailing a whole lot of differences other than temperature (humidity, precipitation, soil composition, ultraviolet radiation, temperature extremes, predators, prey, ...). Meanwhile, back at the hottest end of the site range, there are few populations moving in, because there aren't any sites for them to come from. One of the authors of this lizard study was a guest on the Science Friday radio show on the U.S.'s National Public Radio on May 14. You can listen for free, and see pictures and other material, at http://www.sciencefriday.com/program/archives/201005141. -
neilrieck at 22:53 PM on 16 May 2010Species extinctions happening before our eyes
I just stumbled onto this article and chart which relate "CO2 to Mass Extinctions" over the past 600 million years. www.countercurrents.org/glikson220210.htm The data is attributed to geologist Peter Ward's book "Under a Green Sky: Global Warming, the Mass Extinctions of the Past, and What They Can Tell Us About Our Future" -
johnd at 22:03 PM on 16 May 2010Species extinctions happening before our eyes
quokka at 19:34 PM, I was asking if there was any validity in the statement animals are not able to evolve or migrate quickly enough to adapt. If fauna can evolve into flora in nature as quickly as it seems to have from my post to yours, then it suggest that there is no validity in the original statement. ;-) -
quokka at 19:34 PM on 16 May 2010Species extinctions happening before our eyes
#30 johnd There are any number of reasons why your rosy picture is all wrong. Australia has quite a diverse flora. Some of the reasons include variety of climatic conditions and variety of soil types. The Sydney area for example has a considerable variety of plants adapted to soils over a sandstone base. These populations cannot necessarily pick up their roots and move a few hundred km south if things get a bit toasty for them. And no doubt some of the species of insect that depend on/and are depended on by those plants cannot set sail for more amenable climates without those plants. Rain forests in SE Queensland grow on soils on a basalt base. I've seen a couple of places where the transition from rain forest to dry sclerophyll is so abrupt that you would swear that somebody had built a fence. It's the edge of the old lava flows. Again, relocation for better climate may not be an option. The point is that ecology is complex, far more complex than making rather unjustified inferences from the fact that rabbits and foxes overran Australia. There will always be some species that are as tough as old nails and will survive "anywhere", even in conditions of extreme loss of biodiversity. -
Argus at 19:15 PM on 16 May 2010Species extinctions happening before our eyes
Tom Dayton (#20): Thank you very much, but I have read the 4th paragraph, and it did not answer my question ('how many new local lizard populations have appeared...'). It suggests there are difficulties with migration, but no facts are presented. I am not convinced that they bothered to look for any new populations. On the contrary, the abstract (in the given link) only states they have studied 200 existing sites (in order to see what happened with them). The purpose of the study is to show that local populations go extinct, not to look for new ones forming elsewhere. -
Riccardo at 19:09 PM on 16 May 2010Climate sensitivity is low
PaulK, even assuming that the comparison with climate models is appropiate, my point still stands. One cannot judge the sensitivy just looking at the first part of it, let alone deduce the long term behaviour of the climate system nor of the models. For example, what if the models miss just a damping factor? In the short term they produce larger postive and negative variations, but they will average out. But, as pointed out in my last comment, my guess is that Spencerr will not explicitly say anything like this in the paper, it's something just for his blog. -
johnd at 18:48 PM on 16 May 2010Species extinctions happening before our eyes
re Response "It's the fast pace that is the killer - animals are not able to evolve or migrate quickly enough to adapt." What validation is there for that statement? Many animals, insects or birds are able to migrate very quickly, especially if they are considered pests which seem able to migrate at a faster pace than humans are able to track them. Pests introduced from England quickly overrun Australia even into the hotter arid regions totally different to the English climate. The biggest obstacle may be lack of suitable habitat, lost through reasons other than AGW. Native species are often threatened not because other invading species are too slow to adapt, but because they are far too fast.Response: How do we know that fast climate change leads to mass extinctions? Past history. The fossil record shows us that mass extinction events coincided with periods of dramatic climate change. For more details, follow the link in my previous response. -
PaulK at 18:41 PM on 16 May 2010There's no empirical evidence
#35 Riccardo and #49 Ned You have both argued that the issue of observed OLR increasing over the critical period of 79 to end of century (#34 Guinganbresil and #49 Ned) can be dismissed on the hand-waving basis that it is the response to increasing temperatures. However, I do not believe that this can be easily reconciled with CO2 being the primary driver of temperature increase over this period. For an idealised system the OLR perturbation response to a year-on-year geometric growth in CO2 should be a monotonic decrease in OLR upto the equilibration time and a constant (negative perturbation) value thereafter. The constant composition experiments reported in IPCC AR4 suggest an equilibration time of in excess of 80 years in all the models. The models, at least for those whose results I have seen, also get close to a radiative equilibrium in the 70s by using atmospheric aerosols as approximately equal and opposite forcings to CO2 in order to match the temperature decrease in the period 40s to 70s. Hence, if (over the critical 1979 to 1998 period) TSI variation was negligible and there were no other unaccounted forcings, then we would expect to see a decreasing trend in OLR, and not the increase apparently observed. The increase suggests some combination of (a) CO2 effects were overwhelmed by a SW effect (withdrawal of aerosols or decrease in albedo)(b) the planet was releasing stored energy from somewhere into the atmosphere. In any event, it seems to call into question that CO2 was actually the PRIMARY driver over this period. -
coloursoflife at 16:36 PM on 16 May 2010It's not bad
There is a element of presentation that tends to mislead. I will give an example. There is only one benefit listed for human health, but several detriments. This obscures the fact that in net, warming is benefit to human health. I am not saying it is good for humans, I am saying that the higher temperatures themselves are a benefit. Where do people vacation? In Greenland, or in Crimea? Clearly, the temperatures themselves are not the problem.Response: I'm open to adding more benefits - if you find peer-reviewed papers that show benefits to health from global warming, please post them and I'll add them to the list. -
thefrogstar at 16:23 PM on 16 May 2010Species extinctions happening before our eyes
I think I must have some bad copies of Microsoft-Windows or Adobe-Acrobat, because I cannot find any reference to Carbon Dioxide in this paper. Is it in the supporting information (peer reviewed or otherwise)? Alternatively, if the premise of the article is simply: "If temperatures go up a bit then lots of Lizards will die", then it fills me with admiration for all those dinosaurs who stuck it out for so long. (Not to mention all the 'Mad Dogs amd Englishmen who Go Out in the Midday Sun'). However, there is an even worse conclusion that could be drawn. Temperatures at Football World-Cup competitions have risen since 1966, and England have never won the World-Cup since. This makes sense because the English players (just like reptiles) are not well equiped to handle the heat. The prognosis is, therefore, grim. England may never win another world cup because of CO2 induced "global-warming".Response: The last two sentences of the paper are:Although global efforts to reduce CO2 may avert 2080 scenarios, 2050 projections are unlikely to be avoided; deceleration in Tmax lags atmospheric CO2 storage by decades (4). Therefore, our findings indicate that lizards have already crossed a threshold for extinctions.
Re dinosaurs, when temperatures have changed dramatically in the past, our planet has experienced mass extinctions. It's the fast pace that is the killer - animals are not able to evolve or migrate quickly enough to adapt. -
Tom Dayton at 15:36 PM on 16 May 2010Species extinctions happening before our eyes
thingadonta, please just look up the definition of "population." The ecological definition includes "...occupying a particular geographic area." "Extinction" means vanishing of a population. You can say "extinction of the population that lived in area X." To generalize that phrase to describe multiple such cases, you can say "local extinctions." Biologists have been using the term "local extinction" for a really long time, for reasons having nothing to do with AGW. They have found it useful. The fact that you, a non-biologist, do not find it useful is not relevant to the term's use by biologists.
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