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Comments 120801 to 120850:

120801. watchingthedeniers at 05:55 AM on 17 April 2010
        Earth's five mass extinction events
        And at Chris post 45 - nice summary indeed.
120802. watchingthedeniers at 05:53 AM on 17 April 2010
        Earth's five mass extinction events
        Ty doug for reminder, well worth re-reading.
120803. johnd at 04:24 AM on 17 April 2010
        Flowers 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.
120804. Doug Bostrom at 03:59 AM on 17 April 2010
        Earth'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.
120805. chris at 03:57 AM on 17 April 2010
        Earth'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.
120806. Adam C at 03:32 AM on 17 April 2010
        Earth'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.
120807. JMurphy at 02:39 AM on 17 April 2010
        Flowers 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
120808. Dennis at 02:30 AM on 17 April 2010
        A 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?
120809. JMurphy at 01:12 AM on 17 April 2010
        Earth'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 ?
120810. mark_star at 00:16 AM on 17 April 2010
        Flowers 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!
        
120811. CBDunkerson at 23:22 PM on 16 April 2010
        Arctic 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.
120812. Nick Palmer at 20:26 PM on 16 April 2010
        Over 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...)
120813. watchingthedeniers at 19:55 PM on 16 April 2010
        Earth'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.
120814. thingadonta at 19:02 PM on 16 April 2010
        Earth'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.
120815. Riccardo at 18:41 PM on 16 April 2010
        Arctic 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.
120816. watchingthedeniers at 17:07 PM on 16 April 2010
        Earth'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?
120817. Bern at 17:00 PM on 16 April 2010
        Arctic 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.
120818. Doug Bostrom at 16:51 PM on 16 April 2010
        Are 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
120819. Doug Bostrom at 16:17 PM on 16 April 2010
        Are 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.
120820. shawnhet at 15:44 PM on 16 April 2010
        Are 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, :)
120821. Steve L at 13:42 PM on 16 April 2010
        Earth'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.
120822. iskepticaluser at 13:17 PM on 16 April 2010
        CO2 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.
120823. HumanityRules at 13:13 PM on 16 April 2010
        Earth'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
120824. Doug Bostrom at 12:55 PM on 16 April 2010
        Earth'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? ;-)
120825. watchingthedeniers at 11:01 AM on 16 April 2010
        Earth'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.
120826. thingadonta at 10:50 AM on 16 April 2010
        Earth'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.
120827. watchingthedeniers at 10:41 AM on 16 April 2010
        Earth'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]
120828. thingadonta at 10:39 AM on 16 April 2010
        Earth'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??
120829. michael sweet at 10:05 AM on 16 April 2010
        Flowers 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.
120830. yocta at 09:39 AM on 16 April 2010
        Flowers 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...
120831. Tom Dayton at 09:36 AM on 16 April 2010
        Models 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.
120832. scaddenp at 09:24 AM on 16 April 2010
        Are 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.
120833. scaddenp at 09:19 AM on 16 April 2010
        Models are unreliable
        pdt, you seem to implying that models "tune" the parameters to match climate, but the parametrization is done independent of the models, and the values used in the model. Also note that it is not blind fitting of a statistical function but usually determining the empirical value of coefficients in a functional form derived from the physics. Note also that for some (like clouds), the parametrization can be checked against output of a model with full physics to check for accuracy - its just not practical to use the full physics in a model run. It is also being improved all the time. Either way, even the early Hansen models were way better guide to what the future held just hand-waving about empirical guesses. Of course, there may still be unmodelled physics which is going to save us all - but would you want to bet on such possibility? What the models show, is that with the best physics available to us, our continued emissions of GHGs is going to heat the earth rapidly and we ignore that physics at our peril.
120834. yocta at 09:16 AM on 16 April 2010
        Volcanoes emit more CO2 than humans
        FYI the Icelandic volcano under the Eyjafjallajokull glacier, although still erupting has been clasified as quite low on the Volcanic Explosivity Index compared to Mt Pinatubo which rated a 6 on the 1 to 8 scale.
120835. Doug Bostrom at 09:04 AM on 16 April 2010
        Are we too stupid?
        Shawnhet, the absolute price per KW of generation capacity does not vary according to who pays for it. How about if we pay for subsidies of better generation technology via revenues generated by a carbon tax? A subsidy is after all the output end of a tax, yes? Saying bye-bye to our hydrocarbon slaves is going to cost money, money we can actually see as opposed to the hidden cost of C02 emissions, a sum we're borrowing and simultaneously pretending does not exist. Call it a mitigation fee, a tax, a subsidy, whatever, the cost of C02 has to be brought into our accounting system or we're going to need an entirely new and different kind of "market magic" to make substantial progress with updating our generation systems, the kind of magic that comes from the end of a wand and suffers from lack of existence.
120836. Philippe Chantreau at 09:02 AM on 16 April 2010
        Earth's five mass extinction events
        

        There is new research suggesting that the major factor in the Cretaceous extinction was the Chixculub impact, not the Deccan volcanoes. I'm trying to find the Science article mentioned here: LINK 

        I recall reading that bolide impacts could also be triggers for the kind of activity that left behind the Dekkan Traps and Siberian Traps, but can't find the reference at the moment. In any case, things must be considered in context. The pressure of Human activity and the size of the population alone are enough to drive numerous species to extinction. Rapid environmental changes happening at the same time won't help.

        Moderator Response:

        [RH] Shortened url.

120837. Doug Bostrom at 08:48 AM on 16 April 2010
        Models are unreliable
        It's well worth tracking this matter of clouds through the history of GCM development, fortunately narrated pretty comprehensively by Weart. Mucho references to follow, if you're inclined.
120838. shawnhet at 08:42 AM on 16 April 2010
        Are we too stupid?
        Doug, you seem to think that nuclear power can only be funded privately, in which case you might be right about them being more expensive. However, my point was that rather than spending untold amount of effort to try and make carbon forms of energy more expensive, we can just get our governments to build them directly or to make them profitable through subsidy. This will be **way** easier than what you advocate IMO. Do you think it would be easier to make your neighbor pay for flooding your yard with waste or to pay for a (government funded) common sewer system? Isn't that very ease of application the fundamental reason why sewer systems are common and the "correct" pricing of waste is not? If someone based their whole approach to dealing with waste based on forcing people to correctly price it, wouldn't we say that they were ignoring a much simpler and more effective solution? Regardless of whether PV "should" be more economical now, it will especially if research is funded on it) become much more economical in the future, at some point making more economic sense even than untaxed carbon energy. This is what makes it a pretty good investment *even if there is no government assistance for them*. Cheers, :)
120839. pdt at 08:06 AM on 16 April 2010
        Models are unreliable
        I understand the idea of modeling at that level and have done things like that myself in my professional life. The issue isn't that you will get something utterly unphysical when parameterizations are used outside the fitted range (though that can happen with a poorly formulated model), but that the accuracy may be lower for predictions than for the fit. For example, if a climate model is parameterized by fitting to measured climate data, then those parameterizations are used to predict climate in conditions that do not include the same levels or rates of changes of variables (e.g. CO2 concentrations), then there is very likely greater uncertainty in the predictions than the errors between the model and the actual climate in the fitted range.
120840. cbrock at 05:20 AM on 16 April 2010
        Earth's five mass extinction events
        #14 HumanityRules The phrase "the extinction holocaust" is not a direct quote from the scientist, so you might want to reconsider whether this really represents a scientist "peddling catastrophes". But let's stick to the scientific topic at hand, shall we?
120841. johnd at 05:01 AM on 16 April 2010
        Flowers blooming earlier now than any time in last 250 years
        michael sweet at 02:53 AM. With regards to the tree crops you mentioned, apples in particular. It may be of interest as well as relevant, that apples were introduced into Indonesia by the Dutch more than a century ago, and not only have they adapted to the conditions there, but they are flourishing with significant areas being planted and production, constantly increasing, particularly in recent decades. Indeed it has been Indonesian farmers who have devised techniques that have allowed year-round production to be achieved, all this very close to the equator. Who would have thought that, in the tropics and with climate change and all that supposedly entails? As you noted, people do need to learn more about farming, and perhaps think outside the confines of tightly held beliefs.
120842. Doug Bostrom at 04:14 AM on 16 April 2010
        Earth's five mass extinction events
        Full text of Veron 2008 here: Mass extinctions and ocean acidification: biological constraints on geological dilemmas
120843. Doug Bostrom at 04:10 AM on 16 April 2010
        Earth's five mass extinction events
        A few quibbles, Thingadonta. It's not John Cook who's inferred the possibility of an acidification-related extinction but Veron. So you can take John off your list of physicists making predictions later found wrong. In any case a collection of mostly dead persons are irrelevant to this particular paper. The fact that coral population collapses may occur for reasons other than those Veron surmises says little about his hypothesis. I can think of analogies and so can you, but suffice it say that one failure mode does not exclude another. With reference to past events you say "C02 change is slow", but the change we're concerned with here and now is swift and this is the particul. I committed the sin of failing to drill through John's synopsis and thus was left with a poor understanding of Veron's case. Now that I've actually scanned Veron's paper, I see he's gone through this subject with substantial attention to detail and makes a pretty thorough accounting for his hypothesis. If you've not read it, you ought to do so. Then it would be interesting to see what you say regarding the paper and its claims specifically, as opposed to remarks about typographic errors in John's post and generalizations about past personalities and events.
120844. Albatross at 03:48 AM on 16 April 2010
        Arctic Sea Ice (Part 1): Is the Arctic Sea Ice recovering? A reality check
        What CBDunkerson said @42
120845. Doug Bostrom at 03:46 AM on 16 April 2010
        Earth's five mass extinction events
        Thanks, John. I need to lean a little less on your excellent synopses and drill through into the citations a bit more.
120846. Doug Bostrom at 03:42 AM on 16 April 2010
        Visual depictions of Sea Level Rise
        Argus, I should have mentioned that if you follow this thread of discussion from the beginning you'll pick up a lot of information about how satellite altimetry readings are calibrated. In particular see Peter Hogarth's remarks.
120847. Doug Bostrom at 03:12 AM on 16 April 2010
        Visual depictions of Sea Level Rise
        Argus, not to come off sounding all superior but the designers and operators of these satellites as well as consumers of the data they produce do actually take orbital mechanics into account. If we could wish for anything, it would be for satellites to have been in orbit 200 years ago so we had a better, longer set of data. Longer temporal satellite coverage would help to resolve the kinds of ambiguity you mention regarding regional variances in sea level, most of which are real by the way.
120848. michael sweet at 02:53 AM on 16 April 2010
        Flowers blooming earlier now than any time in last 250 years
        A lot of temperate tree crops (apples, peaches, walnuts, grapes, cherries, kiwis, pears) require a certain number of cold hours in the winter or they will not flower. This article http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2707005/ gives data on climate changes in California causing the failure of tree and fruit crops. It points out that for walnut trees, the orchards take many years to come into production. If the climate changes, the farmers lose their harvest. Since tree farmers have a long outlook on production, they may not invest in new orchards. As climate continues to warm, the area where these trees can be planted shrinks. This addresses two denier issues that have been raised in this thread: 1) The data is from California, not the UK. They have long term, systematic observations. This is a Global issue. 2) These trees are not able to adapt to changes that fall out of their range of chill hours, they stop production. Native trees like pecans, hickory and wild apples (here in the US) will stop producing seeds as it gets hotter and eventually die. New cultivars can be produced for a while but that is expensive, and the orchard is still at risk of future change. I would suggest that if you don't know what chill hours are for tree crops, and you think global warming will not cause any problems, you need to learn more about farming. Of course, seed crops like corn and wheat are also susceptible to climate change, but these trees are affected NOW.
120849. Tom Dayton at 01:23 AM on 16 April 2010
        Models are unreliable
        pdt, a little more description of parameterization is in Timothy Chase's comment on Open Mind. Scroll down to "IV. Regarding the Nature of Modeling," and read the first two paragraphs.
120850. Steve L at 01:10 AM on 16 April 2010
        Earth's five mass extinction events
        Re #23, John you're in pretty good company there! Thingadonta, this may be your best comment here ever, but I have some questions about it. First, you're suggesting that changes due to volcanism over tens of thousands of years are too slow to be compared to what's happening now? Since excess CO2 will remain in the atmosphere for a long, long time, I don't see what you're complaining about. A dramatic change over the course of centuries will not have less impact than the same amount of change over thousands of years. Second, genera taking 10 million years to recover after mass extinctions -- I suspect that you mean the diversity within genera took a while too develop after the pruning that mass extinctions did to the evolutionary tree. But that's not what reef gaps are. Reef gaps are periods of no reef building. Sure, the biodiversity is reduced, but you don't need all of the species to build a reef -- a limited complement of species should be able to do it. So apparently conditions not conducive to coraline growth (low pH) persisted.

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