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batsvensson at 21:10 PM on 17 April 2010Earth's five mass extinction events
chris, 1. It is referring to the OP. Anyway, should I understand your comment that you believe it is a possibility that within, say, the next hundred year all of live in the seas may be dead? 2. What make you believe there is "zero evidence" and that this is "contradicted by what we know"? -
HumanityRules at 20:04 PM on 17 April 2010Flowers blooming earlier now than any time in last 250 years
52.JMurphy at 18:30 PM on 14 April, 2010 These are your words. "why not have a read into how climate change is affecting British species" Not A pointer, "IS" affecting British species. The report IS essentially about hatitat loss the fact that the authors need to kneel at the alter of climate change is unfortunate. -
HumanityRules at 19:55 PM on 17 April 2010Arctic Sea Ice (Part 1): Is the Arctic Sea Ice recovering? A reality check
Peter your figure in #38 somewhat contradicts the "Long term seasonal trends in Arctic Ice extent" in the original article which only records a drop in ice extent since the 1950s. -
HumanityRules at 19:51 PM on 17 April 2010Arctic Sea Ice (Part 1): Is the Arctic Sea Ice recovering? A reality check
34.doug_bostrom at 03:32 AM on 15 April, 2010 35.Riccardo at 05:42 AM on 15 April, 2010 Both seem a little unfair to BP. While he highlights to record he also provides a visual representation over several centuries. Data is data. If we threw away all incomplete data in the climate sciences there would be very little left. I'm also not sure why you'd want a particularly linear decrease in sea ice over a century or more as indicated by the figure in #38.Peter Hogarth. This reconstruction of Greenlands temperature for the past 150 years (fig10) by those infamous skeptics Jones and Briffa suggests that temperatures are far from linear. In fact the 1930's were warmer than present. http://www.cru.uea.ac.uk/cru/data/greenland/vintheretal2006.pdf -
chris at 19:43 PM on 17 April 2010Earth's five mass extinction events
batsvensson, I was addressing your assertion that: "However, I do not think we need to worry for anoxia to appear on a global level (i.e. kill a majority of all marine life) the atmosphere would need to be depleted of oxygen for this to happen." and pointing out that the atmosphere doesn't need to be depleted of oxygen for this (anoxia) to happen. Not sure what your point about "anoxia" refers to anyway. The main environmental stressors for coral morbidity/mortality are warming and ocean acidification, both of which are happening and likely to be increasingly problematic in the coming decades. As for your "hypothesis"; why would we propose or consider a hypothesis for which there is not only zero evidence, but which is robustly contradicted by what we know of the real world? I don't see how it takes us anywhere scientifically speaking... -
HumanityRules at 19:36 PM on 17 April 2010Arctic Sea Ice (Part 1): Is the Arctic Sea Ice recovering? A reality check
#48 http://www.wgms.ch/mbb/sum08.html The world glacier monitoring service preliminary data for 2007/2008 suggests 1/3 of studied glaciers are advancing while overall there is a nett retreat. The need to qualify glacier advancement seems like a bias in the outlook of the reporter. No real need to explain the many complex variables of retreating glacier the answer in that case is obvious! -
Riccardo at 18:53 PM on 17 April 2010Trenberth can't account for the lack of warming
by the way, here is Science Perspectives article and here UCAR press release. -
batsvensson at 18:23 PM on 17 April 2010Earth's five mass extinction events
@ Chris #51 1. I am not aware of any known process that suggest that the oceanic circulations are going to stop even slow down. Are you? 2. I wrote "hypothesis", not "theory". -
Riccardo at 18:20 PM on 17 April 2010Trenberth can't account for the lack of warming
plazaeme, i find weird your contrasting between science and scientists. But anyway, i find even stranger that a skeptic like Pielke fail to recognize the limitations of our observing system, which is the mantra of the skeptic world including Pielke. Trenberth's point is quite simple, we can not close the energy budget and this can not be explained just by errors in satellite measurements. The obvious conclusion is that our observing system is not fully adequate to the task. I would have guessed that everyone could agree. -
chris at 17:53 PM on 17 April 2010Earth's five mass extinction events
You’re still making fundamental errors of logic thingadonta Volcanoes during the Cretaceous. Eruptive tectonic activity (volcanoes; igneous province eruptions etc.) were active during much of the Cretaceous at a level that resulted in raised greenhouse gas warming and an increase in the carbon cycle at a rate around double that of present. The fact that volcanic/tectonic activity makes no significant contribution to raised greenhouse levels now, but did then isn’t a difficult concept to grasp! Volcanos/tectonic activity isn’t “only important when it’s convenient”; the activity is important when it’s important, and unimiportant when it’s unimportant. We live in a contingent world where things change, and thus events and contributions are different at different times in Earth history. If we’re considering the effects of raised greenhouse gas levels (and sulphurous oxides) on global temperature and ocean acidification, then that’s the essential point and we can’t make categorical statements about what volcanoes, or people or impacts can or can’t do, and then ignore the evidence. Anything that raises greenhouse gas/sulphurous oxide levels quickly will cause rapid warming, and rapid ocean acidification. That seems to be what happens at the KT boundary, and the evidence indicates rapid ocean acidification and rapid extinctions. Likewise greenhouse gas levels are rising rapidly now, temperatures are rising rapidly and ocean acidification is increasing rapidly. The fact that many of the extinctions in the deep past seemingly occurred as a result of processes happening over long periods, doesn’t preclude the likelihood that processes that act quickly (bolide-induced vaporization of calcium carbonate and sulphate deposits; massive, rapid oxidation of long-sequestered fossil fuels), may result in rather rapid extinctions. The end Cretaceous informs us of that (see refs. in my post #45; the lesser PETM extinctions are another example). Ocean buffering mechanisms. The major ocean buffering mechanisms are (i) the very slow ocean circulations that dilute the effects of local perturbations on the 100’s to 1000 year timescale; (ii) the carbonic acid-bicarbonate-carbonate equilibrium that acts to maintain the pH of the oceans. While this makes the oceans resistant to change in pH, it doesn’t make it impervious to change, and in fact we know that rapid increase in CO2 levels (and perhaps massive vaporization of sulphates such as likely occurred at the KT impact), can overwhelm the buffering capacity of the oceans, particularly the important surface regions (upper several hundreds of metres). Since we have strong evidence that this occurred rather quickly following the KT impact (see papers linked in my post #45), and can measure the acidification of the oceans in the real world, we can hardly base our views on a mantra that “it takes tens of thousands of years to change them”. A very rapid increase in the surface absorption of atmospheric acids can overwhelm both the chemical buffering and the ocean circulation contributions to buffering. Again, when things change slowly they change slowly; when they change quickly they change quickly! There are no set rules. Incidentally many relevant elements of ocean buffering can be rather easily transferred to the lab. The H2CO2 = HCO3- + H+ = CO3-- + H+ equilibrium is straightforward and well understood, including its response to acidification. Lkewise the aragonite saturation that is crucial for shell and skeleton formation by many marine organisms is rather well understood and can be transferred to the lab. There’s a huge scientific literature on this (see for example papers in a recent issue of Oceanography recent issue of Oceanography , and refs in/cites of this). Coral bleaching. To assert that “corals get over it all the time” and referring to “seasonality”, is not relevant. We’re not considering variations (especially temperature and pH) within a range to which populations are adapted. We’re considering very rapid persistent trends (in sea temperature and acidity) towards regimes to which corals are poorly adapted. Real world observations indicates corals are increasingly unable to “get over it”. -
plazaeme at 17:40 PM on 17 April 2010Trenberth can't account for the lack of warming
You may try to know what "the science" (whatever that is) says, or you may try to know what the different scientists say. In the later case, and unless you think Roger Pielke sr. is not a scientist, you may be interested in this debate: http://pielkeclimatesci.wordpress.com/2010/04/16/is-there-missing-heat-in-the-climate-system-my-comments-on-this-ncar-press-release/ -
embb at 17:30 PM on 17 April 2010Are we too stupid?
Guys, it is nice discussion but you forget the original article: the point is that any pricing of carbon emissions will create "game theoretical traps" like the tragedies of the commons. Google can want whatever they can imagine (e.g. a have seen a calculation of how much CO2 emission is caused by a google search so thjey will probalbly warmly welcome a tax on internet searches) the traps are there and waiting. Any measure that does not calculate with these traps and just wishes they were not there is bound to fail - like Kyoto. -
thingadonta at 16:17 PM on 17 April 2010Earth's five mass extinction events
#45 Chris: The extinctions you refer to are not 'rapid' (KT/ POTM). They occur over tens of thousands or years+. This is the main issue, and why papers such as Veron are wrong/misleading. Verons article on 'coral reef crisis' is an exercise in exageration. Have a look at his language designed to produce the greatest exageration possible: "degraded water-quality and increased severe weather events." Both not true. Severe weather has not increased. When reefs are impacted by severe weather, they always recover, you would think they have evolved to, after millions of years of 'severe weather'. Opportunistc species rebuild them, as in after volcanic eruptions in the Pacific, Krakatoa etc. "other environmental impacts." ie if you run out of enough 'disaster' words, just say 'other environmental impacts', that way you don't have to explain it. "Perhaps most importantly, there is no evidence that reefs have ever experienced true parallels to today’s anthropogenically-driven combination of stressors." Baloney. End Permian, end K/T, POTM. All 3 took tens of thousands of years. All 3 worse than now. Veron wants us to believe that puny humans can outbeat the Siberian Traps several hundred thousand years of explosive volcanism. His statement that we have lost 19% of reef since 1970 is a gross distortion. (We should get Macintyre and Lomborg onto these coral reef exagerators). What's more, if temperatures have risen, this promotes coral reef growth at the margins of their range: eg Southern Barrier reef etc, I know this partly becuase I studied this area and this issue in my honours thesis. Nowhere does he mention that the ocean has buffering mechanisms which cannot be easily reproduced in the laboratory, and which make oceans VERY resistant to rapid chemical change, as the geological record shows (which is why it takes tens of thousands of years to change them and for marine species to go extinct in geological time periods). Veron completely ignores this, because it is in his interest to promote as much 'quick catastrophism' as possible. Mass coral bleachings are a natural event that occured before the 1970s, there is 'little record of it' before this because no one was looking. Communities in the Pacific have recorded it for hundreds/thousands of years. "The 1997/1998 mass bleaching event killed approximately 16% of coral communities globally (Berkelmans and Oliver, 1999; Wilkinson, 2004). It was also the start of a decline from which there has been no significant long-term recovery." Incorrect, corals are used to such events, it occurs seasonally all the time including at the margin of their range, and they get over it all the time, Veron does not. The article link by Caldera shows he doens't know much about the K/T exinction. He doesnt even mention the delcine of marine organisms from well before Chicxulub about 70Ma. He doesnt mention the Decaan Traps either, and yet this were the major cause of the maine extinctdions (not the impact), the bolide impact was too short to produce long lasting marine effects. He also mentions that the earth was warmer in the Cretaceous because volanoes were spewing out more c02. But I thought volcanic c02 was so minor as to be irrelevant? So it's only important when convenient. IE Volcanoes can change climate on long time scales, but not short ones, humans can change climate on short time scales, but they cant take a geological long time to do it, even though volcanoes have to. (Somebody tell the volcanos because they arent listening). If Veron and co. are the measure of 'well informed scientists' regarding the next announcement of impending doom, then I don't think we have much to worry about. -
Kevin Hood at 14:23 PM on 17 April 2010Arctic Sea Ice (Part 1): Is the Arctic Sea Ice recovering? A reality check
For those wondering above where glaciers are advancing, you can see a few of them in Southeast Alaska in the maps shown on pages 5 and 6 of this report but they are surrounded by many more that are wasting. Also, as the author suggests in the Discussion (#5 at page 7), the reason for advancement may be due to increased precipitation feeding glaciers whose bodies lie predominantly at higher elevation. In other words, climate change (more moisture in the atmosphere) may be contributing to their advancement. To be fair, he notes that there are many complex variables affecting glaciers - but his maps of how many are wasting are pretty sobering. -
michael sweet at 10:02 AM on 17 April 2010Arctic Sea Ice (Part 1): Is the Arctic Sea Ice recovering? A reality check
The website Cryosphere Today cryosphere today has a lot of data and animations on arctic and antarctic ice. They show their data using ice area, not extent like the NSIDC does (the data comes from NSIDC). I have followed them for about two years and there is little difference between the area and extent graphs. This year Cryosphere Today shifted to a thirty year baseline (NSIDC uses twenty years) and that made more difference than extent versus area. They have an interesting ap where you can compare any two days in the arctic ice record to see the difference between different years. Cryosphere Today rarely comments on the data. In the current era of data being challenged by sceptics I think ice extent is easier to defend to laymen. The extent data is simple and requires little massaging to obtain. -
chris at 08:59 AM on 17 April 2010Earth's five mass extinction events
batsvensson at 07:56 AM on 17 April, 2010 (i) anoxia certainly doesn't require the atmosphere to be depleted of oxygen. Anoxic ocean events in the deep past seem to have resulted from elements of greenhouse-induced warming, temporary cessation of deep ocean circulation and ocean stratification. Try this (not very well written) Wikipedia page on anoxia (ii) we know the reason for the current increasing atmospheric CO2. It's not due to a "current ongoing (mass) extinction"! -
cbrock at 08:44 AM on 17 April 2010Earth's five mass extinction events
#49 batsvensson Thanks for pointing out the Rothman paper; it's interesting. I should note that also in Rothman's conclusion is a disclaimer, "Indeed, our analysis leaves open the possibility, for example, that tectonically induced reductions of CO2 levels led to increased diversity in both continental and marine ecosystems. A definitive statement of causation will require further work that includes not only the study of other geochemical signals (10) but also improved paleontological records." This is frequently one of the problems with (necessarily temporally coarse) ancient paleo data--the resolution is not always there to make a strong causal determination. One then has to look at the physics and known biogeochemistry to evaluate one hypothesis vs. another. -
batsvensson at 07:56 AM on 17 April 2010Earth's five mass extinction events
We should worry about CO2 level in the sea, but for the right reasons. As marine life, for physiological reasons, are more sensitive to (even small) changes in CO2 concentration than terrestrial life then it is something we should be considered about (at least those of use that likes to eat sea food.) However, I do not think we need to worry for anoxia to appear on a global level (i.e. kill a majority of all marine life) the atmosphere would need to be depleted of oxygen for this to happen, but fortunately this is not a very likely scenario in the near future (but will eventually happen when the sun turns into a red giant - then we can talk about real global warming, however any acidification of the sea’s at that time will become a minor problem by then ;). About the plausible theory that CO2 can cause mass extinction. It can not be excluded that elevated levels of CO2 in the past has been a consequence of a previous mass extinction: In the conclusion of "Global biodiversity and the ancient carbon cycle (Rothman)" we can read: "we find that the correlations express complementary fluctuations in the size of the organic and inorganic carbon reservoirs within the biosphere, atmosphere, and hydrosphere. Consequently, CO2 levels decreased as biodiversity increased. These conclusions imply that fluctuations of CO2 levels have been driven primarily by changes within the biosphere and only secondarily by purely geologic and geophysical processes." Some final food for thoughts here: Consider Rothman’s paper, then we may postulate a hypothesis that the current increasing of atmospheric CO2 concentration is a consequence of an current ongoing - for some reasons - (mass) extinction. -
watchingthedeniers at 05:55 AM on 17 April 2010Earth's five mass extinction events
And at Chris post 45 - nice summary indeed. -
watchingthedeniers at 05:53 AM on 17 April 2010Earth's five mass extinction events
Ty doug for reminder, well worth re-reading. -
johnd at 04:24 AM on 17 April 2010Flowers blooming earlier now than any time in last 250 years
JMurphy at 02:39 AM, firstly I think posting export figures for a commodity that primarily satisfies domestic consumption is rather misleading. Indonesia has about 2 million apple trees and the annual production from the main growing region is about 200,000 tonnes annually, small by most standards, but certainly much bigger than your figure. I would not consider myself relaxed, but I am certainly not an alarmist. I feel that instead of constantly wringing our hands about halting climate change, whatever the reason for it, something I doubt can be achieved, it is better to concentrate on the efforts being made to adapt to a changing climate, and it was for that reason I mentioned Indonesia, it being only one amongst several where most people would not expect apples to be grown. Given commercial production on a large scale generally results in a loss of diversity amongst most food crop varieties, it is perhaps that lack of diversity that might be the biggest obstacle to being able to adapt to changing conditions in the worlds largest orchards. The migration of production of animals or plants is not a new phenomena, nor only forced by climate change. Discovery of new areas, or changing economics have perhaps forever forced production of one commodity to move from one part of the world to another, the fine wool Merino sheep being such an example. There are certainly large areas of the world that are suitable for apple production to transfer to if current areas fail to adapt, but it may that such changes will be forced more by economics than climate change given how fast the global economic environment is changing. -
Doug Bostrom at 03:59 AM on 17 April 2010Earth's five mass extinction events
Sorry to be redundant but here again is the link to the Veron paper John discusses: Mass extinctions and ocean acidification: biological constraints on geological dilemmas I bring it up again because the paper covers a tremendous amount of previous research, addresses most of the concerns about past events mentioned in the thread of discussion so far. -
chris at 03:57 AM on 17 April 2010Earth's five mass extinction events
Thingadonta, Your analyses are flawed. As already pointed out, the fact that some extinctions of the deep past occurred during (apparently) very long periods (100’s of 1000’s of years) doesn’t preclude the likelihood that very rapid perturbations of the climate system (on the 100’s of years time scale, or even less) can’t produce extinctions on much faster timescales. The end Cretaceous extinction is a case in point. It’s quite likely that this extinction was the result of a long environmental stress resulting from the massive flood basalt events that formed the Deccan Traps with a coup de grace resulting from the Yucatan impact into calcium carbonate and calcium sulphate-rich deposits. That extinction very rapidly wiped out all land animals bigger than a cat, and caused massive extinction of marine organisms. The marine extinctions were likely due to rather rapid acidification of ocean surface waters. There’s lots of evidence that supports this view (reviewed here and here[*], for example). Pretty much all marine species that inhabited the surface water columns and that fixed calcium carbonate disappeared likely due to rapid ocean acidification. As indicated in the top article, coral reefs disappeared (not to return for 2 million years). All plankton with calcium carbonate shells disappeared for ½ a million years. What strongly supports ocean acidification is the fact that diatoms that have silica shells didn’t disappear, and nor did some deep sea floor species that weren’t affected by sea surface acidification on timescales shorter than those required to dilute the acidification through the entire oceans. These extinctions were very fast. And acidification of the especially important and vulnerable top hundreds of metres of the oceans can occur rather quickly (Adam C just pointed that out). That’s been described in a recent review of evidence for ocean surface acidification (especially the consistent finding worldwide of a reduction of biogenic calcite in the spherule layers associated with deposits from the impact-se second link in paragraph above). Rapid release of CO2 on the hundreds of years timescale will cause acidification of the top hundreds of metres of the ocean on a similar timescale. In fact, it is the rapidity of release of acid-forming gases (CO2 and sulphurous oxides) that is especially dangerous for the oceans, and the reason that the end Cretaceous and Paleo Eocene Thermal Maximum are significant analogues for today’s massive and extraordinarily rapid release of greenhouse gases. The very slow release of CO2 right through the Cretaceous with the resulting greenhouse warming drove the carbon cycle around twice as fast as today with the result that there was an extraordinary richness of calcerous marine animals (the “Cretaceous” is named after chalk – latin “creta” for that reason). But when greenhouse gases and sulphurous acids entered the atmosphere very rapidly, so the ocean extinctions resulting from rapid ocean acidification followed. This is all pretty obvious I think. After all, we know that since around 1970 we’ve lost around 19% of coral reefs and around 35% of the remainder are threatened. We have good evidence that there are relatively recent occurrences, since we can observe since the 1970’s the widespread bleaching of long lived (600 year old) coral species. So far the dominant effect has been temperature since the major pulses of coral bleaching and die-off is occurring during the El Nino episodes riding on the background rise in ocean surface temperatures. However we’re getting pretty close to the CO2 levels where many of the carbonate-fixing species simply won’t be able to produce their skeletons. That’s also described in a recent review by Veron and a large number of well-informed scientists. [*] can’t find an on-line pdf of this one. -
Adam C at 03:32 AM on 17 April 2010Earth's five mass extinction events
re: 41 "I am skeptical when you want to change an entire ocean's chemistry in less than tens of thousands of years" I don't think anyone's suggested that. The problem is a change in the acidity of the surface layer of the ocean, at a pace too rapid for it to be dispersed into the deep ocean. -
JMurphy at 02:39 AM on 17 April 2010Flowers blooming earlier now than any time in last 250 years
johnd, I'm interested in the responses you have had to your post about apples in Indonesia. As far as I can tell, they export about 35 tonnes a year, as opposed to, say, France's 1.5 million tonnes; and they have to defoliate their trees by hand after every harvest, to get the trees to produce again. Do you really think that means that we have nothing to worry about and that apple production won't be affected by climate change ? I really am interested as to how you can be so relaxed about these things, so perhaps you could explain why you are, with reference to apple production - especially with regard to the replies from michael sweet and yocta -
Dennis at 02:30 AM on 17 April 2010A database of peer-reviewed papers on climate change
Poptech @50: Do you know the names of any climate scientists who have peer reviewed climate science papers in Energy & Environment? Can you list them here? -
JMurphy at 01:12 AM on 17 April 2010Earth's five mass extinction events
Anyone knowing about Plimer and his most recent error-strewn book, would not attempt to use him for any sort of back-up to an argument, even in fields he is supposedly expert in. His credibility is in shreds. As for the naturalistic fallacy, perhaps that should be added to the one that sees those in denial using past changes in climate as some sort of response to why humans can't possibly be changing the climate now - replied to by asking whether forest fires starting naturally in the period pre-man, means that man can't now start forest fires. Is that a logical fallacy ? -
mark_star at 00:16 AM on 17 April 2010Flowers blooming earlier now than any time in last 250 years
Cornell University (Wolfe 2004) study describes an advance of spring Phenology from 2 to 8 days over 1965 to 2001 for observed perennials in the northeast USA. Do you want these paywalled articles in the database? http://www.springerlink.com/content/dfw7db58c8pbm4af/Response: Definitely do submit any and all peer-reviewed papers into the database, whether paywalled or not. Even if it is paywalled, often a search on google scholar will find the full PDF floating around, particularly for papers more than a year or two old. And if you can't find the full PDF, I find emailing the author/s is usually fruitful, particularly if you start your email with a compliment about how interesting their research is :-)
Also, I submitted your link to the database, thanks for the URL! -
CBDunkerson at 23:22 PM on 16 April 2010Arctic Sea Ice (Part 1): Is the Arctic Sea Ice recovering? A reality check
Volume = ice area * average thickness Extent = ice area / average concentration (15% to 100%) The past two years the minimum extent has increased while the volume has continued to decrease. Looking at the formulas above we can quickly deduce that this suggests the ice has gotten thinner but more spread out. Which makes perfect sense because it is easier for thinner ice to be broken into pieces which can drift away from each other rather than remaining one large solid block. In short, the recent small increase in extent is IMO actually a bad sign. Given that the ice is thinner and more broken up I'd expect to see a significant increase in ice area and extent... as in my example where a 1000 cubic foot solid block broken into 1 cubic foot components could go from covering an extent of just 100 square feet to as much as 6,667 square feet. The comparatively minuscule increase in extent observed over the prior two years suggests that not only is the ice getting thinner, but more of it is also melting away entirely... leaving a smaller area of thinner ice which is just spread over a larger area of the ocean. -
Nick Palmer at 20:26 PM on 16 April 2010Over 31,000 scientists signed the OISM Petition Project
I've posted this before but I haven't seen the point understood yet. The actual wording of a major part of the petition is so constructed that even fully legit climatologists - even James Hansen - could happily sign it. It is this bit (the second paragraph): There is no convincing scientific evidence that human release of carbon dioxide, methane, or other greenhouse gases is causing or will, in the foreseeable future, cause catastrophic heating of the Earth's atmosphere and disruption of the Earth's climate. The weasel wording is "is causing or will", which are 100% definitive statements (there's no probability in them). Catastrophic heating/disruption is by no means certain so the average pernicketty scientist could sign with a clear conscience. The first paragraph may have just been skated over by respondents as out of date now (by mentioning 1997...) -
watchingthedeniers at 19:55 PM on 16 April 2010Earth's five mass extinction events
@ 41 Re KT/Cretaceous extinction: see my post @ 34 in which 2010 Science paper confirms Chicxulub as cause of dinosaur extinction here. Cite your references, not popular TV show. Re Deccan Trap theory the stress is on *may*: "Eventually, most paleontologists began to accept the idea that the mass extinctions at the end of the Cretaceous were largely or at least partly due to a massive Earth impact. However, even Walter Alvarez has acknowledged that there were other major changes on Earth even before the impact, such as a drop in sea level and massive volcanic eruptions that produced the Indian Deccan Traps, and these may have contributed to the extinctions." Your post: "So I don't know how pro AGW people use the past geological record to scare us about short human lifetimes. It's like a biologist scaring us about our rate of speciation..." ~ Actually, if we are talking about viruses then, yes speciation could be alarming. AIDS is a perfect example where it made the species jump from host it's chimpanzee population into the human population. The virus itself mutates with alarming frequency, thus developing many strains. Re using the geological record, to be frank the state of exobiology is such that we only have *one planet* in which to base our speculations on. As a consequence, it is perfectly reasonable to use the geological and paleontological record as a basis for drawing conclusions. Re Plimer, he is a geologist NOT a paleontologist or biologist. Just like his views on climate change, he is operating well outside his areas of expertise. As a consequence, his understanding of mass extinction events,their causes and the like are limited. Re you last comment: "What matters is the time periods involved" Again, I think my point about you falling into the naturalistic fallcy is correct. Ironically, you use the supposed length of time of extinction events to somehow prove your point but then chastise us "alarmists" for using the geological and paleontological data ourselves. -
thingadonta at 19:02 PM on 16 April 2010Earth's five mass extinction events
A few points: re 39 Steve L. "I think you are misinterpreting #35. Or maybe I am. It seems that #35 says that less total CO2 released, but released quickly over a short period of time, cannot have a similar impact as a lot of CO2 released over a longer time period. I believe this is wrong. " I am skeptical when you want to change an entire ocean's chemistry in less than tens of thousands of years, taking the geoligical record as a starting point. This is how long the geological record generally says it takes, even under extreme scenarios. So I dont know how pro AGW people use the past geological record to scare us abvout short human lifetimes. It's like a biologist scaring us about our rate of speciation. This is one of the main skeptic arguments -ie the time it takes to change the oceans, warm the planet etc etc (add it to the list), and is similar to the arguments in palaeontology and biology over gradual evolution versus punctuated equilibrium. That is, how fast is 'rapid/punctuated' versus 'gradual' when you are referring to geological time periods? It's a question of semantics really, eveyone agrees that the rate of evolution can change, but gradualists are very skeptical of any 'jumps' or 'jerks' or 'rapid' rate changes. (It also harks back to the days of the catastrophists and the uniformitarians in the 19th century -Darwin was a a uniformatirian and got it wrong with regards to 'mass extinction' events (he thought they were just gaps in the fossil record), Cuvier was a catastrophist- like nearly all pro-AGW people, and got it right with to mass extinction events). But as for mass extinctions, we are talking in most cases, of hundreds of thousands of years. Skeptics, therfore, contend that for somnething like ocean acidification by C02, it will take about that long to do it, which makes current humnan activities regarding ocean acidification, irrelevant. We can never release the kind of amount of gases that Siberian and Decaan Traps volcanism can do over several hundred thousand years in order to change ocean chemistry. Skeptics contend that various pro AGW researchers have vastly ignored and downplayed the time periods involved with most mass extiction events, and exagerated their own figures to scare people (like Jones with Siberian temperature data). Skeptics also contend that by the time the ocean acidifies (if it does at all, it is well buffered in many other respects in its interactions with volcanoes, sediments, Mid oceanic ridges etc etc?) from human c02, say in about 10,000++ years (?), we will have long ago given up our reliance on fossil fuels. (If this figure seems way too long, that is what is usually meant by 'geologically rapid', conveniently distorted by some coral reef researchers). As for K/T and #34, bolide impact pushed species over the edge after Decaan Traps volcanism had already weakened many ecosystems and which had begun several hundred thousand years earlier. Species were already in decline, especially marine species. This is well established. It was not one or the other (volcanism or bolide impact), it was both. re #32 The Chicxulub impact did not cause Decaan Traps volcanism, becuase it was already well underway (several hundred thousand years) before the asteriod/comet hit Mexico. Species were in decline already for about the previous few million years (including the dinosaurs-have a look at eg the "Walking With Dinosaurs" series-this is well established in peer reviewed literature, volcanic gases/effects were already killing the eg dinosaurs before they were pushed over the edge to oblivion by the asteroid. It was a one-two punch, which is why it was such a major extinction event). You can understand it this way, mass extinctions are by nature worse when a combination of factors are involved. There have been many large impacts in earth hoistory with no mass extinctions. re#36 "Accelerated release is not contingent upon causation being either "natural" or "human induced". What matters is the chemistry/physics. " What matters is the time periods involved. Mass extinction events take hundreds of thousands of years to change the chemistry of the oceans. Ask a volcanologist (which is one reason why Plimer is such a skeptic-one of his pet topics is volcanology-and he is more informed about what they do to oceans, as Veron is not). If someone wants to counter most of the above, they have to show how the past geological record shows the oceans can acidify in a few hundred years from changes in c02 levels. As far as I know, it says no such thing. -
Riccardo at 18:41 PM on 16 April 2010Arctic Sea Ice (Part 1): Is the Arctic Sea Ice recovering? A reality check
I'm going to be a bit pedantic. If the trend is not statistically significant we can not refuse the null hypothesis, i.e. that we didn't get the result by chance. This does not mean that you can claim the opposite, you just can say nothing. In our case, we have a statistically significant downward trend while the recent upward trend is not. We must conclude that the probability of having the short term upward trend by chance is high. @ Bern i'm still in a pedantic phase :) Statistics won't tell you anything about wether or not the trend will continue in the future. It may eventually allow you to claim that there has been a trend in the past. For example, there is a statistically significant downward trend every spring but you can count on the opposite trend in autumn. To predict the future you need a physical model. -
watchingthedeniers at 17:07 PM on 16 April 2010Earth's five mass extinction events
@ 39 I may have misinterpreted. Here is the para I focused on: "But my point is, all this took hundreds of thousands- to millions of years of vast amounts of c02 etc from Siberian Traps volcanism-oceans didn't,and probably won't, acidify quickly-ie less than tens of thousands of years?, if they do from humans at all." I read that to imply he/she questioned how human activity could result in acidification. He posits time periods and natural processes and contrasts (by implication) possible human interactions with the climate. That's how I read it. (see last sentence) It could be we are *both* reading the different things into the post because the argument is muddled and attempting to argue both points? -
Bern at 17:00 PM on 16 April 2010Arctic Sea Ice (Part 1): Is the Arctic Sea Ice recovering? A reality check
Re the short-term trend - yes, the passage of time will tell us whether it's a statistically significant trend, but by then it will be a long-term trend, not a short-term one... :-D I think that's the whole point re the 'statistical significance' - there's not yet enough data to show whether this is a trend that may continue, or a short-term upward variation in a downward trend. The null hypothesis, of course, being that the existing (downward) trend continues, and this is a short-term fluctuation. Thanks to the folks who provided the references on ice volume - very informative. I suppose decreasing volume at the same time as increasing extent means thinner ice which will melt that much faster during summer. Will be interesting to see what happens this year. -
Doug Bostrom at 16:51 PM on 16 April 2010Are we too stupid?
Here's an example of what I'm babbling about incoherently in my crazy way w/regard to carbon pricing. A struggling private enterprise known as "Google" is also managed by crazy persons: Google wants a price on carbon and wants it now -- both for lofty reasons like combating global warming, but also because it could be good for business. As the Senate inches closer to climate legislation that could give the Internet giant what it wants, I checked in with Dan Reicher, the director of climate change and energy initiatives at Google to see what surfing the web had to do with reining in greenhouse gases. Turns out, the answer is technology. Reicher -- a former Department of Energy assistant secretary who now directs Google's investments in clean energy -- believes that exposing the hidden costs of dirty fuels will set off a rush of investment in new energy innovations. He says carbon pricing is an "essential signal we have to get to." Right now, "money is sitting there to make significant investments," he says, but the cash flow is sidelined because the incentives aren't there. Google climate change chief wants price on carbon -
Doug Bostrom at 16:17 PM on 16 April 2010Are we too stupid?
Shawnhet, I think I'm correct when I say that the only place we've seen nuclear power adopted on a substantial scale sufficient to largely displace other means of generation is (as you point out) France, where it was made possible by massive public expenditure, via taxation. Elsewhere than France, the same technology is available and would be installed if the market deemed it financially attractive. It does not; if the market found nuclear power acceptable, we'd see it more widely deployed. I fully agree with you that C02 emissions will have to be substantially reduced in order to fix our problem. In fact, I'm not sure where we fully disagree (perhaps we're similarly crazed?) except with regard to your original incorrect assertion that the EU was increasing its GHG emissions despite government intervention of the type and scale you find attractive in France. Is it crazy to collaborate with my neighbor to rectify damage my neighbor and I are inflicting on one another by ignoring environmental costs? Is assigning a cost to our effluent (sewer tax, CCF charge, whatever) and then disposing of sewage using funds recovered from that cost assignment so crazy? I don't know, maybe you should ask your utility or other governmental entity if they believe they and you are crazy? Without some incentive of one form or another we'll burn every scrap of coal we have, until doing so becomes expensive on par with the next most expensive substitute. This in not some kind of controversial hypothesis, it's exactly what's happening today. Wishing the market away with hypothetical and especially unfunded and thus unbuilt technological fixes won't work. Cash incentives will. As long as coal is burned because we choose to ignore the costs doing so inflicts on us, no wishful thinking is going to solve this problem. So tell me, how are you going to get an investor to pay twice as much for a nuclear plant as he would for a coal plant? How are you going to persuade tax-averse Americans to pay twice as much for their generation capacity using tax dollars, and where will those tax dollars come from? In fact, the money for replacement generation plant is going to have to be extracted from somebody, us ultimately, and if that can be done in the form of a levy that simultaneously places a powerful incentive on ditching C02 emissions, so much the better. -
shawnhet at 15:44 PM on 16 April 2010Are we too stupid?
Doug, you seem to be pretty confused on this issue, so I'm not sure that there is much more I can add, I will just recap the points here as I see them. #1.You've been arguing that it is impossible to deal with this issue without properly accounting for (what you feel is) carbon's cost. However, this is clearly not the case. Have the French accurately accounted for the cost of carbon? Probably not, from your POV, but that doesn't stop them from emitting much less carbon by using nuclear technology. Again, you are acting like a crazy guy here who thinks he must properly account for the cost of his neighbor's waste instead of arguing for the construction of a sewer system. Personally, I have no idea what the "correct" cost of a month's waste dumped in my yard might be, but since I live in an area with sewers, it is not really necessary for me to know that. #2. You seem to misunderstand the scale of the supposed problem here. The fact is, that if catastrophe is looming, CO2 would have to be substantially reduced, not merely held flat. Even if everyone adopted the exact same approach as the best of the European countries, that would still be nowhere near close enough. #3.As time goes by, conservation efforts of one sort or another will get less and less efficient, in the absence of radical technological change. #4. OTOH, technological change will enable much more efficient conservation as time goes on. If current trends continue, solar power will equal fossil fuel's cost effectiveness(even at today's rates) in somewhere btw 20-40 years. Presumably, once this happens, we won't need to figure out what the correct cost of carbon-based energy, as everyone will more or less automatically switch to solar. Cheers, :) -
Steve L at 13:42 PM on 16 April 2010Earth's five mass extinction events
#36, I think you are misinterpreting #35. Or maybe I am. It seems that #35 says that less total CO2 released, but released quickly over a short period of time, cannot have a similar impact as a lot of CO2 released over a longer time period. I believe this is wrong. To support my assertion I tried to look up a figure (I thought it was in Caldiera and Wickett 2005, but my search didn't find a free version of the full paper). My Google search took me to some other interesting stuff. I particularly like the powerpoint presentation (fifth down on the list) -- lots of references and lots of relevance to the discussion above. Go here. Similar but less stuff (and more explanation) is shown in this pdf. Of particular interest to me in the slide show is the information on other important factors (carbonate!). It would be a very long term project for me to study the all the references to permit me to make a good summary. Hopefully someone with more expertise will do it instead. -
iskepticaluser at 13:17 PM on 16 April 2010CO2 effect is saturated
NkThrasher #7: the whole concept of saturation is based on a misconception of how radiation is passed up, level by level, through the atmosphere. Spencer Weart has some good non-technical descriptions of this, which I've adapted here. -
HumanityRules at 13:13 PM on 16 April 2010Earth's five mass extinction events
31.cbrock What you think NewScientist choose to include that phrase themselves? Seems unlikely from a level headed publication, if true it's possibly worse given NS has more impact than a single scientist -
Doug Bostrom at 12:55 PM on 16 April 2010Earth's five mass extinction events
Here we go, another log on the cheery fire of discussion: Increasing concentrations of carbon dioxide in sea water are driving a progressive acidification of the ocean1. Although the associated changes in the carbonate chemistry of surface and deep waters may adversely affect marine calcifying organisms2, 3, 4, current experiments do not always produce consistent results for a given species5. Ocean sediments record past biological responses to transient greenhouse warming and ocean acidification. During the Palaeocene–Eocene thermal maximum, for example, the biodiversity of benthic calcifying organisms decreased markedly6, 7, whereas extinctions of surface dwellers were very limited8, 9. Here we use the Earth system model GENIE-1 to simulate and compare directly past and present environmental changes in the marine realm. In our simulation of future ocean conditions, we find an undersaturation with respect to carbonate in the deep ocean that exceeds that experienced during the Palaeocene–Eocene thermal maximum and could endanger calcifying organisms. Furthermore, our simulations show higher rates of environmental change at the surface for the future than the Palaeocene–Eocene thermal maximum, which could potentially challenge the ability of plankton to adapt. Rate of ocean acidification the fastest in 65 million years Now mind you, the actual paper title is "Past constraints on the vulnerability of marine calcifiers to massive carbon dioxide release" but who am I to deny a blog titled "Desdemona Despair" its little bit of fun? Besides, the more punchy version is after all the title of the press release from U. of Bristol and "fastest in 65 million years" is after all the result. So paleo data, models, a sexy press release. What's a rejectionist not to like? ;-) -
watchingthedeniers at 11:01 AM on 16 April 2010Earth's five mass extinction events
@ 35 thingadonta A version of the naturalistic fallacy? Just because "Event A" happened under "natural conditions" over XXX Ma does not preclude it happening in the short term future. Accelerated release is not contingent upon causation being either "natural" or "human induced". What matters is the chemistry/physics. One would think the idea of positive feedback loops (release of the reserves of Co2 and CH4 when we reach the right "tipping point")) are crucial to understanding the issue. -
thingadonta at 10:50 AM on 16 April 2010Earth's five mass extinction events
#23 Steve RL. "So apparently conditions not conducive to coraline growth (low pH) persisted". IE for ~10Ma. In the case of coals, there is a 'coal gap' between 250 Ma to ~240 Ma, the plant species that produced most of the coal in The Late Permian went extinct at the end of the Permian and had to re-evolve-, so there is virtually no coal on the East Coast of Australia from about 250-240Ma(ie from the Sydney-Bowen Basin-which royalties pays a reasonable proportion of East Coast academic salaries-you don't hear much appreciation though). Coal produced after 240Ma was from different plant species than previously, you also get a lot of red beds at this time indicating hothouse conditions. But my point is, all this took hundreds of thousands- to millions of years of vast amounts of c02 etc from Siberian Traps volcanism-oceans didnt,and probably won't, acidify quickly-ie less than tens of thousands of years?, if they do from humans at all. -
watchingthedeniers at 10:41 AM on 16 April 2010Earth's five mass extinction events
@ Philippe Chantreau post 32 Are we talking about the K-T boundry line here and the creataceous mass extinction event? I thought his was regarded as the mainstream/consensus view. I understand there is still some debate on the issue. What is the most recent peer revieweed lit on this? However, SciAm referenced a study here as the "definative consensus view" on the issue.: "...A group of 41 researchers have pored over the evidence and decided that—in accordance with the original postulate put forth 30 years ago by a team led by father and son researchers Luis and Walter Alvarez—it was, indeed, a massive asteroid that slammed into Earth, creating Chicxulub Crater on Mexico's Gulf Coast, that killed off many of the species on the planet, including the non-avian dinosaurs. The review, published online March 4 in Science, evaluated the whole picture, according to Kirk Johnson of the Research and Collections Division at the Denver Museum of Nature and Science and co-author of the paper. And that meant assessing the other theories that have been put forth about what spelled death for the dinosaurs..." Study published in Science here : "...The temporal match between the ejecta layer and the onset of the extinctions and the agreement of ecological patterns in the fossil record with modeled environmental perturbations (for example, darkness and cooling) lead us to conclude that the Chicxulub impact triggered the mass extinction." [from abstract] -
thingadonta at 10:39 AM on 16 April 2010Earth's five mass extinction events
Thanksfor the link paper, One question before I may respond more fully (I am in the remote field at the moment using VSAT satellite collecting real data in the real world, and not making up pretty coloured models on a computer screen, and of course, who am I having to deal with right now, people using pretty coloured maps on a computer screen which are wrong and exagerated and which I am fixing in the field with real data, but I digress). my question: -the Siberian Traps ejected vast volumes of eg c02 over several hundred throusand years+, and it took coral reefs to collapse over hundreds of thouands of years (and possibly, oceans to acidify-although this is not clear) hso how can less amounts of c02 from humans acidiy the oceans in a few decades-hundreds of years?? -
michael sweet at 10:05 AM on 16 April 2010Flowers blooming earlier now than any time in last 250 years
JohnD. It is certainly possible for new methods to be developed. As I mentioned, new cultivars can be developed. I have 4 peach trees here in Florida for example. However, it is expensive and risky to have to develop new culltivars constantly to keep the produce coming. What will these changes cost? Are the new varieties as good as the old ones? Are farmers willing to take on the risk? Some changes cannot be managed: cherries need a lot of chill and I have not seen low chill varieties. Natural forests do not have the option of developing new trees. The old trees will die off and be replaced by trees adapted to the new conditions-- if the new conditions last long enough for them to grow. It seems to me that a better approach is to minimize change to minimize adaption expense. It may be more costly to adapt than to reduce carbon emmisions. -
yocta at 09:39 AM on 16 April 2010Flowers blooming earlier now than any time in last 250 years
RE# johnd 83 I never thought my favourite Fuji could be so interesting! This is an interesting paper I just found about apples in Java, albeit slightly dated. (Rosmahani et al. 1988) And if I quote from parts of it “...The first successful cultivation of apples in Java was recorded in 1934 (Rosmahani et al., 1988), but it took more than 40 years for research in apple culture to achieve its present development. One of the challenges in growing temperate fruit in the tropics is simulating mechanisms that prevent bud dormancy in the absence of temperature and daylength variation.... Like most exotic species from temperate origins, in the tropics apple trees are vulnerable to pests and diseases. The high humidity of tropical mountains allows for the growth of certain fungal diseases that destroyed most of the apple trees in Java during the 1970s. Present cultivation of apple trees relies on the frequent application of heavy doses of pesticides and fungicides.” So yes I agree it is quite marvellous that the farmers have developed techniques, I am not share your optimism about the suitability of the land use overall for these particular crops, as the paper concludes: ...Instead of developing into a system with a high biological diversity that requires low inputs, apple-based farming systems are increasingly simplified, allowing only a limited choice of intercrops. The system also relies heavily on chemical inputs... -
Tom Dayton at 09:36 AM on 16 April 2010Models are unreliable
Yep, pdt, I agree with you that the accuracy of the predictions likely will be lower than for the fit. So researchers keep trying to reduce the numbers of parameters they use, and to improve the estimates of the parameters they must use. The claim (not yours!) I was initially responding to was the misperception that the climate models' predictions are evaluated against the same data that the models were statistically fit to in the first place. By the way, there is more discussion of parameterization on Open Mind, especially starting with Ray Ladbury's comment. When you get down to Tim's comment below Ray's, skip it because Tim then posted a correction and then a final correction. -
scaddenp at 09:24 AM on 16 April 2010Are we too stupid?
And how much of a no-brainer is ending any kind of subsidy on any industry that is a CO2 emitter? I am well aware that this will result in unemployed coal miners, etc - deal fairly to them by all means but their jobs are not a reason for messing the planet.
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