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Ron Crouch at 00:58 AM on 12 May 2010Heat stress: setting an upper limit on what we can adapt to
From Thermoregulation Quote: "The lower limit of temperature that humans can endure depends on many factors, but no one can survive a temperature of 45 °C (113 °F) or above for very long. Mammalian muscle becomes rigid with heat rigor at about 50°C, with the sudden rigidity of the whole body rendering life impossible." So remember that the temperature inside your car can easily climb over 50C even with the windows cracked. Guess what happens to Fido. Heat stress for production animals generally diminishes in 24C (75F) and above conditions depending on the animal involved, with onset generally in the 24C to 28C range. There are lots of data on the net to support this. Obviously then the amount of land area that would become uninhabitable through dry bulb temperatures exceeding ~44C would also increase. -
RSVP at 00:19 AM on 12 May 2010Estimating climate sensitivity from 3 million years ago
"If the amount of CO2 in the atmosphere is doubled, the change in global temperature without feedbacks would be around 1°C." For the last 100 years, CO2 has gone roughly from 250 ppm to 380 ppm, a ratio of 1.52:1. If the above is true, global warming should be around 1.52 / 2 = 0.76 C. Since climate models assume the Earth's temperature holds within a strict equilibrium, the effect of every extra exothermic calory released since the beginning of the Industrial Revolution should (to some degree) be having a cumulative effect. How can this not be accounted for, especially by those who maintain that with more CO2, the ability of the Earth to discharge heat has diminished? The "non skeptic" replies to this question typically indicate that this waste heat is comparably small, however the value provided is only given for one year as opposed to 100 or 200 years. A balance scale analogy may be helpful. If 100 kilos are hung across a balance scale, and then a dash salt is added from a salt shaker on one side, a significant movement is not expected; however, if a dash of salt is added everyday for 200 years, eventually the scale will tip. As energy cannot be destroyed, it must be accumulating. I think the phrase, "you cant have it both ways" applies, such that if the Earth's thermal balance is so delicate, one cannot ignore the effects of human waste heat, and that some significant part of heating is not coming from CO2. In either case, it is coming from the use of non renewable energy sources. -
ianw01 at 00:12 AM on 12 May 2010Heat stress: setting an upper limit on what we can adapt to
The sharp cutoff of the red Tw plot deserves further explanation. Clearly there is a phenomenon that causes the upper cutoff despite the higher temperature (black) and max temperature (blue) curves. Until the Tw curve is explained, it does not necessarily follow that the Tw curve will shift right as temperatures rise. One would think it should rise, but one would not expect that sharp upper cutoff. -
Arkadiusz Semczyszak at 23:51 PM on 11 May 2010Heat stress: setting an upper limit on what we can adapt to
It should be noted that the warming of 6 degrees C (and more), an increase of temperature (mostly) in the cold season. In tropical regions, such as during eemian, could be even colder than it is now ... Theory of a tropical thermostat - confirms it: no adjustment to temperature changes in the coral, similar areas inhabited by gorillas (Africa), etc.. It is also worth noting that even evolutionarily oldest tropical plants are not adapted to higher temperatures than at present. Meanwhile - in cold zones: e.g. Dr Jim Provan, from Queen's School of Biological Sciences, describes in his works a huge potential adaptation (for warm) of algae in the Arctic. Cod tolerate swings in temperature + / - 8 degrees C ... In ancient times the warm (6-12 ° C more than today), underwent extension in the temperate zone of marine version (6-8 degrees), or tropical mild (> 7-9 degrees) - for nearly the entire globe. Do not threaten us, then year-round heat. For example, heat waves in Europe (2003, 2006), only effects of violent La Nina - CLAW hypothesis - not GW. -
John Russell at 23:32 PM on 11 May 2010Heat stress: setting an upper limit on what we can adapt to
Thanks, John. I've learnt something. Having also been in tropical rain forest in extremely high humidities I'd assumed that I'd also been in equally high temperatures in those conditions; but I guess I haven't or I wouldn't be here to tell the tale.Response: Damn, you've had an interesting life, John. Working from home, it's a good day for me if I manage to get out of the house. -
Jacob Bock Axelsen at 22:11 PM on 11 May 2010Heat stress: setting an upper limit on what we can adapt to
Other sideeffects of global warming includes asthma and allergies from pollen and fungii, malaria/West Nile virus/dengue fever from spreading mosquitoes, tick borne Lyme disease and perhaps a 30% increase in kidney stones from dehydration. Coming global warming could even be the greatest health problem according to experts. Take a minute to contemplate just how radical a statement that really is when it comes from false positive averse experts. -
Ned at 22:01 PM on 11 May 2010Heat stress: setting an upper limit on what we can adapt to
CBDunkerson writes: Thus, long before any portion of the Earth would reach the point of regularly experiencing lethal conditions we are going to see large portions of the globe being hit by them every few decades. This is a very important point. When thinking about the economic and biological impacts of climate change, it's essential to look at the variance, not just the mean. Obviously, it would be disastrous if the global mean temperature increased to the point where Tw exceeded 35C in Texas, Senegal, and New South Wales every year. But it would still be disastrous if temperatures only increased to the point where that happened during the one-sigma heat waves a couple of times per decade, or even the two-sigma heat waves every twenty years or so. -
quokka at 21:51 PM on 11 May 2010Heat stress: setting an upper limit on what we can adapt to
Berényi Péter: If you go to the "4 Degrees and Beyond" conference presentations download page: http://www.eci.ox.ac.uk/4degrees/programme.php and download Dr Richard Betts presentation on regional climate change, there are a number of global maps showing model projections for regional temperature anomalies for various warming scenarios. The map for a global anomaly of 5.4C is truly frightening in it's regional implications. 4C is bad enough. -
Ned at 21:50 PM on 11 May 2010Heat stress: setting an upper limit on what we can adapt to
Berényi Péter, that raised a red flag for me when I first read this paper. However, they are very clear in the introduction that this is (a) a worst-case scenario, and (b) a projection beyond the traditional horizon of 2100. If you assume that climate sensitivity is in the upper 5% of the accepted range, that no serious mitigation measures are undertaken, and that population growth and industrialization of developing countries results in the consumption of a larger fraction of coal reserves over the next 200 years, a mean temperature increase of 10C or more is possible (more at NH high latitudes, less in the tropics). I think James Annan would probably dispute this approach. Personally I'd like to see any discussion of this paper clearly emphasize that it's based on a "worse" (perhaps not "worst") case scenario rather than on the most probable scenario. On the other hand, given the chance of seriously intolerable outcomes for much of the world, I do think it's necessary to consider less-likely but possible negative scenarios. IPCC's forecasts have turned out to be too cautious in some cases, after all. In any case, Sherwood and Huber 2010 explain this quite clearly in their first paragraph, with references. Have you looked at the paper yet? -
Ari Jokimäki at 21:41 PM on 11 May 2010Estimating climate sensitivity from 3 million years ago
HumanityRules (#48) wrote: "Is there any justification for putting one year memory rather than leaving it out?" Yes. In an earlier study Lin et al. found that the climate memory is at least 8 years, so putting in a short memory instead of no memory is better. But of course, when you are dealing with the real life you need to use a memory > 8 years. -
CBDunkerson at 21:38 PM on 11 May 2010Heat stress: setting an upper limit on what we can adapt to
We already see this effect in current weather cycles. The European heat wave of 2003 killed tens of thousands of people. Another in Europe and the US in 2006 killed a few thousand. Then again in 2007 a few thousand more in Asia. That is all weather, but in a warming climate the weather conditions for high temperature and humidity occur more frequently. Thus, long before any portion of the Earth would reach the point of regularly experiencing lethal conditions we are going to see large portions of the globe being hit by them every few decades. It would be interesting to see what Tw was in decades prior to 1999 or by year rather than decade. If it has been creeping up, as seems likely given the increase in temperatures (and thus perforce also humidity), then it represents a measurable 'fatality index' to global warming which could be correlated against heat wave deaths. -
chris at 21:36 PM on 11 May 2010Estimating climate sensitivity from 3 million years ago
A somewhat related paper was published not long ago also in Nature Geophysics which also indicates the possibility of very significant longer term amplification of greenhouse-gas induced temperatue rises via poorly understood mechanisms. Obviously we are aware of the possibility for what might be considered catastrophic non-linear consequences of warming (rapid collapse of polar ice sheets; massive release of methane from hydrates etc.). Unfortunately it's not straightforward to factor these into the analyses of mitigation and adaptation policies. R. E. Zeebe et al. (2009)Carbon dioxide forcing alone insufficient to explain Palaeocene–Eocene Thermal Maximum warming Nature Geoscience 2, 576 - 580. -
Ned at 21:29 PM on 11 May 2010Estimating climate sensitivity from 3 million years ago
Chris, I agree 100%. The last thing the IPCC (or anyone) should be doing is classifying papers into "skeptic papers" and "pro-AGW papers" and then for the sake of evenhandedness being sure to cite three from column A and three from column B. There have been lots of good studies of climate sensitivity. Some find higher values (Lunt 2010, Hansen) while others find lower (James Annan). IPCC should and does consider the range of findings among strong, well-conducted studies in the literature. On the other hand, there are also papers about climate sensitivity that have serious flaws (Chylek here and here, or Lindzen & Choi here). I don't think IPCC should overlook those flaws and give them unwarranted consideration for the sake of offering "equal time" to all sides. The only distinctions that should matter are whether a paper is insightful, robust in its methods, justifies its conclusions, and leads to further productive research. -
Berényi Péter at 21:23 PM on 11 May 2010Heat stress: setting an upper limit on what we can adapt to
Would someone explain how temperature at (sub)tropics could increase by as much as 7 °C and more? -
chris at 21:18 PM on 11 May 2010Estimating climate sensitivity from 3 million years ago
HumanityRules at 17:48 PM on 11 May, 2010"Your list doesn't seem to include any of the so-called sceptics papers?"
Actually I've just had a look at Ari Jokimäki's list. Of course it depends on what you mean by "so-called sceptics papers", but if you mean papers by individuals that arrive at low climate sensitivity by hopelessly flawed analysis, or more generally any paper that infers a cimate sensitivity below the likely IPCC range (e.g. below 2 oC of equilibrium surface warming per doubling of atmospheric [CO2]), then the list has lots of "so called skeptics papers". e.g. referring to my brief list in post 49 above, Ari has: Chylek and Lohmann (2008) Schwarz (2007) Shaviv and Veizer (2003) and there is also: Washington and Meehl (1989) Mitchell and Ingram (1989) Gillard and Schneier (1984) (Idso (1980) -
Riccardo at 20:53 PM on 11 May 2010Heat stress: setting an upper limit on what we can adapt to
It's interesting to notice that the body temperature of mammals, including us humans, falls within a relatively narrow range. We all share the need to dissipate heat and the "last resort" of perspiration. So we also share roughly the same wet-bulb temperature limit. This limit can be found in any introductory physics textbook for biomedical sciences but this is the first time I see it applied to humans in their environment on a global scale. Great. -
Ed Davies at 20:13 PM on 11 May 2010Heat stress: setting an upper limit on what we can adapt to
Any thoughts on heat-stress effects on animals, domesticated and wild? Even vegetarians need animals in many tropical areas for ploughing and transport.Response: Good point, I forgot to include that they do mention mammals in their study. One of their concluding paragraphs reads (emphasis mine):In principle humans can devise protections against the unprecedented heat such as much wider adoption of air conditioning. But the power requirements of air conditioning would soar; it would surely remain unaffordable for billions in the third world and for protection of most livestock; it would not help the biosphere or protect outside workers; it would regularly imprison people in their homes; and power failures would become lifethreatening. Thus it seems improbable that such protections would be satisfying, affordable, and effective for most of humanity.
They also mention earlier that "Any exceedence of 35 °C for extended periods should induce hyperthermia in humans and other mammals, as dissipation of metabolic heat becomes impossible." So obviously heat stress will have a significant impact on livestock which will affect food supply. -
John Russell at 19:59 PM on 11 May 2010Heat stress: setting an upper limit on what we can adapt to
When working in the Kalahari desert in Namibia I've been in temperatures of 45 degrees C for periods of an hour or two. It's extremely uncomfortable, even in the shade. At same time as I've been in discomfort with a camera on my shoulder, wearing shorts and a light cotton shirt, I've been filming locals transplanting, weeding or harvesting crops who are wearing dark trousers, shirts and loose dark-coloured jackets -- some even with woollen hats. I guess I learned that, provided there is a supply of clean fresh water, humans can hang on almost anywhere -- speaking geographically -- though I doubt whether it'll be me or thee. This comment should in no way be taken to mean that I don't think that efforts to avoid climate change should not be of the highest priority.Response: The wet-bulb temperature is different to air temperature. In a desert environment, the wet-bulb temperature is lower due to the low humidity. This is why desert areas show the same wet-bulb temperature as more humid tropical regions. -
chris at 18:44 PM on 11 May 2010Estimating climate sensitivity from 3 million years ago
HumanityRules at 17:48 PM on 11 May, 2010 on your:"It would be worrying if the IPCC were to do the same. Having divided off a group of scientists, labelled them denier, questioned their motives it then seems possible to behave as if they don't exist."
That's silly HR. The IPCC consider all scientifically valid research. The authors consider the topic of their particular remit in its entirety, assessing all the published literature and other relevant data sources. So they will know aboput your so-called "skeptic papers" and these are considered on their merits in line with the available science. So if a paper is shown to be incorrect, this may not be mentioned, or more likely will be discussed in terms of the data that denonstrate its flaws (since bad science does have its uses). Your notion of "skeptic papers" is a curious one. As far as I can see there are only papers. Anything that is published in a scientific journal is a scientific paper, and having got there it lives or dies according to the interest it generates, the criticisms it generates and so on. The notion that there is some sort of alternative "science" of "skeptic papers" is a dodgy one to me. Of course there are a tiny amount of knowingly scientifically invalid papers that are winkled into the scientific literature (of the thousands of papers on climate science published a year, there might be 3 or 4 of these; they're often the ones we hear about!). But if that's what you mean by "skeptic papers" why would the IPCC or any scientific body or group consider these when assessing the state of a scientific field??? Your second sentence in the quote from your post is breathtakingly hypocritical! Clearly some rather scurrilous groups are attempting to do what you suggest (witness the pathetic and rather disgraceful attacks on Professors Mann and Jones). You can see by reading some of Poptech's post the way in which some people use these attacks as a means of attempting to disregard (in the manner you suggest) anything from the sources (e.g. Poptech on the CRU temperature data). But in fact the situation from the scientific side is straightforward. Spencer and Braswell, and Chylek, and Schwartz, and Lindzen and Choi were published (flaws notwithstanding). The reason that we reject these papers as valid contributions to our knowledge is that they hve been objectively shown to be flawed. mostly by extensive critique in the form of publications by others. It's certainly not because we reject them out of hand. Obviously we are likely to be a little suspicious of papers from certain sources but that's the price paid by those that attempt to sneak bad science into the scientific literature! -
chris at 18:27 PM on 11 May 2010Estimating climate sensitivity from 3 million years ago
Which "skeptic" papers HumanityRules? Lindzen and Choi has been objectively shown to be incorrect. They cherrypicked their timepoints, and made incorrect assumptions that are fatal to their interpretations. Schwarz's paper on climate sensitivity using a simple model of ocean heat capacitance and "guessed" response times was shown to be objectively incorrect. He recognized this and published a correction which now shows that in his model the apparent climate sensitivity isn't below the IPCC range anymore. Chylek's paper on the estimation of low climate sensitivity from examination of temperatures and atmospheric reflectance during ice age transitions was shown to be objectively incorrect. Like Lindzen and Choi, Chylek et al made non-objective selection of time points. Similar flaws effectively sink papers on climate sensitivity by Spencer and Braswell, and by Shaviv. etc. etc. Why would one include papers that are objectively wrong in a list of papers that inform us about earth climate sensitivity? If we want to understand phenomena in the real world we reject analyses that have been demonstrated to be incorrect. which papers did you consider should be on your list? -
HumanityRules at 17:48 PM on 11 May 2010Estimating climate sensitivity from 3 million years ago
45.Ari Jokimäki Is there any justification for putting one year memory rather than leaving it out? Your list doesn't seem to include any of the so-called sceptics papers? It would be worrying if the IPCC were to do the same. Having divided off a group of scientists, labelled them denier, questioned their motives it then seems possible to behave as if they don't exist. -
Riccardo at 17:37 PM on 11 May 2010Estimating climate sensitivity from 3 million years ago
Berényi Péter, there's no formal definition of slow or fast feedbacks, they must be considered relative to the time scale analyzed. -
Berényi Péter at 17:07 PM on 11 May 2010Estimating climate sensitivity from 3 million years ago
What are the timescales involved? I understand slow feedbacks are supposed to operate on timescales from hundreds to thousands of years. But how fast are fast feedbacks? Days? Weeks? Years? Decades? -
tobyjoyce at 16:46 PM on 11 May 2010Climate Change and the Integrity of Science: a letter to Science
@johnd #216 I am disappointed you could not substantiate your assertions, which I will now ignore completely as a rhetorical overstatement, and without real foundation. It seems to me that you should be one doing the research. You could start by reading the thread on climate sensitivity at this blog. The thread lists links to 12 papers on climate sensitivity. In none of them do the authors confess "doubts", other the wish to refine their analyses. Climate Sensitivity -
Ari Jokimäki at 16:24 PM on 11 May 2010Estimating climate sensitivity from 3 million years ago
Recently a paper was published that addressed Spencer's feedback studies, I wrote a brief piece about it. The paper addresses the Lindzen stuff also, but there's not much hope for Lindzen anyway, and I don't think there ever was. If people are keen to look for lot of climate sensitivity papers, here's a list of some of them. -
Phila at 15:17 PM on 11 May 2010Climate Change and the Integrity of Science: a letter to Science
#212 "it wasn't to provide any proof but rather simply to show that climate varies widely" Why does this need to be shown? Is there anyone on this site who doesn't know that climate varies widely? Or that it's complex? In my experience, people who accept AGW know this already. More to the point, they understand that complexity and uncertainty can lead to understating risk, as well as overstating it. -
Stephen Baines at 15:07 PM on 11 May 2010Climate Change and the Integrity of Science: a letter to Science
Geo Guy #216 Good, we can agree that atmospheric SO2 is largely produced by man (actually about 90%). That's a start. Your comparison of CO2 and SO2 emissions are WAY off, though (really, you need to check your units!) In 2004 CO2 emissions were 38 GIGATONS (AR4 IPPC). More than 30% of that entered the ocean - or conservatively about 12-13 Gt. Global SO2 emissions even at the peak of emissions in the 1990 were only about 154 million tons (or 0.154 Gt) according to the World Resources Institute – much more than you claimed but a lot less than CO2 emissions. Less than half of SO2 emissions get to the ocean (36-51 % according to Dentener et al (2006)) because it rains out so quickly. Most estimates I have seen suggest more like 30-40% - not that different from CO2. So basically ratio of SO2:CO2 entering the ocean is similar to SO2 and CO2 emissions, about 1:1000. But buffer chemistry is complex, right? And there are other strong acids in human emissions. What of them? There was a paper in Proceedings of the National Academy of Sciences (Doney et al 2007) that directly addressed the effect of sulfur and nitrogen deposition on ocean acidity and found that it amounted to only a few percent of the effect of CO2 over the whole ocean. Locally, near the coasts, acidic N and S deposition could contribute a larger fraction of acidification. There is nothing close to the effect of acid deposition on pH of lakes though. That requires a poorly buffered system, which the ocean is not. Still, since marine organisms are sensitive even to subtle changes in pH, it provides yet another reason for controlling emissions of these compounds - especially near China where emissions are skyrocketing. Some other issues I have with your post… the residence times of SO2 or CO2 in the atmosphere have NOTHING to do with their specific gravities (relative to air) as pure gas. If you had a balloon of pure CO2, sure, it would sink in our atmosphere. But you may have noticed that CO2 does not exist as balloons of pure gas in our atmosphere. Rather it is a trace gas mixed among other gasses. The gravitational pull on single molecules is nowhere near enough to offset mixing due to turbulent motion or even Brownian motion. Good thing, too. If CO2 molecules sank they would collect near the surface of the earth and we would all asphyxiate. You and would not be having this edifying discussion. You are right that SO2 IS much more soluble than CO2 in dilute water. Actually sulfate particles for this reason often form nuclei for condensation of droplets – implicating them in cloud formation. It also explains why SO2 gas has a residence time in the atmosphere very similar to water – ie, days – because it rains out with the water. Finally, it explains why SO2 cannot build up in the atmosphere to any great extent or travel much more than 1000 miles from the source. In the US SO2 concentrations in air are typically below the health standard set by the EPA, which is <0.03ppm or >10,000x lower than CO2. Refs Dentener et al., F. (2006b). Nitrogen and sulfur deposition on regional and global scales: a multimodel evaluation. Global Biogeochem. Cycles, 20:GB4003. doi:10.1029/2005GB002672 Doney et al (2007) Impact of anthropogenic atmospheric nitrogen and sulfur deposition on ocean acidification and the inorganic carbon system. PNAS 104:14580-14585. -
scaddenp at 12:54 PM on 11 May 2010Climate Change and the Integrity of Science: a letter to Science
Geoguy - And Mann 2009 not to mention that science moves on and there is all the other paleo reconstructions in AR4 WG1. What do you do you see as the importance of this? -
Rob Honeycutt at 12:44 PM on 11 May 2010Climate Change and the Integrity of Science: a letter to Science
@Geo Guy... John Cook also addresses the hockey stick issue in other pages on this site. -
Rob Honeycutt at 12:35 PM on 11 May 2010Climate Change and the Integrity of Science: a letter to Science
@Geo Guy... You do also realize that there is a more recent Mann paper on climate reconstructions. Mann 2008. Here is Mann's response to McIntyre and McKitrick. I would assume that if you read Mc&Mc you would want to continue to understand both sides of the debate as fully as possible. -
yocta at 10:08 AM on 11 May 2010Kung-fu Climate
Cool, links have been posted to the various sites in which people can follow this further if they choose, so I guess we can call it a day here on this one :) -
JMurphy at 09:56 AM on 11 May 2010Kung-fu Climate
Yocta, fair enough. It gets very dizzy going round and round in circles...! -
Geo Guy at 09:51 AM on 11 May 2010Climate Change and the Integrity of Science: a letter to Science
Stephen Baines # 206 Everything in the ocean has a source that can be linlked to land. Industrial sources in the northern hemisphere account for most of the man made SO2 in the atmosphere. Other sources are volcanic which are spatially located in the volcanic belts around the world. SO2 has a lower hafl life than CO2 for 2 reasons: 1) higher specific gravity (2.3 vs 1.5) and greater solubility (80/1.7). Wolfgand Knorr concluded in his study that the trend in airborne fraction of anthropogenic CO2 has essentially remained constant since 1850 http://www.agu.org/pubs/crossref/2009/2009GL040613.shtml According to the US EPA domestic SO2 emissions fell from 31 tons to 19 tons between 1970 and 1999. The same figures for CO2 were 197 and 89 respectively. If we take 1970 as an example, the ratio of SO2 to CO2 emissions calculates to .15. If we calculate the same ratio for solubility, we get 40. Hence we can have more CO2 in the atmosphere but because the SO2 solubility factor is so much greater, a smaller amount of SO2 can have an equivalen effect on the pH of water, including the Ocean. On another point, the prevailing winds are from west to east and with most of the US industrial complex located on the east coast, a lot of SO2 emissions will get blown out over the ocean. In addition SO2 is just behind CO2 in terms of gas emissions from volcanoes so I feel that SO2 does play a more important role on the acidity of the oceans than some people are willing to give it. -
yocta at 09:49 AM on 11 May 2010Kung-fu Climate
This thread has gone way OT. With regards to the Poptech situation, it is probably in the best interest for newcomers to the site to not have to read through the back and forth commenting that is going on here. There are plenty of other blogs where the exact same thing with Poptech has gone such as GREENFIRE that JMurphy linked to. Let that kind of talk go on there. The strength of SkepticalScience is that this kind of talk is avoided and it provides a friendly domain for discussion of the topics at hand no matter how ignorant a person may seem. For the benefit of undecided readers who follow the threads we should be focusing our attention on what they will take away from reading the comments. Cluttering the post up will only confuse them. Keep in mind a lot of people follow the threads here but don't actually comment themselves. Obviously, there are plenty of ill-considered opinions to be found either side of any issue, but only the most ignorant person could fail to see the terrible intellectual gulf between the quality of so-called skeptic sites and those defending the science behind the AGW thesis. -Recent converted skeptic from realclimate.org Lets keep SkepticalScience the way it should be! PS on a lighter note folks, watch this. This is how you truly deal with climate skeptics: -
JMurphy at 09:28 AM on 11 May 2010Kung-fu Climate
Round and round we go. Poptech wrote : "In Brooks case his paper supports skepticism of tornadoes getting worse due to global warming." As Dikran Maruspial has also mentioned, that is not correct and Brooks has previously asked you to back up that assertion. All I have to do is copy and paste Harold Brooks's comment to you when you last claimed to know more about what his paper was about than he did : Can you provide one citation in the scientific literature AGW will lead to increased “tornado activity?” Also, the relationship between “activity” and damage is not at all direct. All that we looked at were the most damaging individual tornadoes and the relationship between those tornadoes and overall activity is not obvious. You failed last time (except perhaps in your own mind) so perhaps you are now able to come up with a better (and more relevant) response this time ? As for your later comment : The word "serious" is subjective. I consider the journal serious. All of which is irrelevant as the journal is peer-reviewed. The article you linked includes various misinformation about the journal which is corrected here, Correcting misinformation about the journal Energy & Environment Not only do we find you referring to your own opinion to determine how serious a journal is (it doesn't matter what anyone else thinks, right ? All that matters is that you think it is 'serious'), but you also use a link back to your own website to try to claim vindication for that opinion. Who can argue against someone who KNOWS he knows more than anyone else, and who is able to back up this knowledge by referring to himself ? -
chris at 09:08 AM on 11 May 2010Estimating climate sensitivity from 3 million years ago
johnd at 02:23 AM on 11 May, 2010 johnd, michael sweet is right. I also don't know if those numbers for "industrial heat"are correct. However the "forcing" from any industrial heat generation applies only to the extent that the heat generation takes place (if all industrial activity were to cease, the heat would be rapidly dissipated to space). So this tiny forcing is essentially a constant. The forcing from increments of atmospheric CO2 is cumulative. Doubling of atmospheric [CO2] gives a net radiative forcing of 3.7 W.m-2. Notice that the feedbacks are manifest only in the presence of the forcing. If the forcing is (i) reduced or is (ii) a steady state, the feedback will (i) fall back, or (ii) steady out to a new level. In fact since the industrial heat has been fairly constant for several decades, we've likely had most of the tiny, tiny feedback from this tiny tiny forcing. Water vapour is only "additive" as a feedback response to a radiative forcing, or some other phenomenon (volcanic eruptions, changes in solar output) that changes the atmopheric temperature. It is the latter that governs the water vapour concentration. In fact the enhanced water vapour concentration in response to greenhouse gas forcing is readily measured in the real world [***], consistent with the expectations from well-established theory of radiative effects in the atmosphere and their feedbacks. Incidentally, the observation that atmospheric humidity is rising as predicted from theoretical understanding of the greenhouse effect, is one of the additional bits of evidence that a low climate sensitivity (less that 2 oC of warming per doubling of [CO2]) is unlikely. ------------------------------------------------ [***] Dessler, A. E., Z. Zhang, and P. Yang (2008), Water-vapor climate feedback inferred from climate fluctuations, 2003–2008, Geophys. Res. Lett., 35, L20704 Gettelman A and Fu, Q. (2008) Observed and simulated upper-tropospheric water vapor feedback J. Climate 21, 3282-3289 Buehler SA (2008) An upper tropospheric humidity data set from operational satellite microwave data. J. Geophys. Res. 113, art #D14110 Brogniez H and Pierrehumbert RT (2007) Intercomparison of tropical tropospheric humidity in GCMs with AMSU-B water vapor data> Geophys. Res. Lett. 34, art #L17912 Santer BD et al. (2007) Identification of human-induced changes in atmospheric moisture content. Proc. Natl. Acad. Sci. USA 104, 15248-15253 Soden BJ, et al (2005) The radiative signature of upper tropospheric moistening Science 310, 841-844. -
johnd at 08:58 AM on 11 May 2010Estimating climate sensitivity from 3 million years ago
michael sweet at 08:44 AM, is not the forcing from direct heat energy also additive. Water vapour increases 6%-7.5% per deg C. Given global temperatures have risen about 5 deg C since the last ice age a simple calculation suggests that water vapour has increased from about 15,000ppm to about 20,000ppm whilst CO2 has increased from 280ppm to 380ppm. The numbers may not be exact but they are meant to illustrate that water vapour is additive and not tied directly to CO2, but responds directly to heat input. -
johnd at 08:45 AM on 11 May 2010Climate Change and the Integrity of Science: a letter to Science
tobyjoyce at 08:02 AM, all I can suggest then is that you do your own research and when you find evidence that the matter of climate sensitivity (which still rests on the matter of cloud feedback) has been finally resolved, please post such evidence. I simply haven't got the time or the inclination to seek out and post every single reference to the fact that the matter remains unresolved when you could settle it with just one reference that provides proof it has been resolved, something you have avoided doing so far. -
michael sweet at 08:44 AM on 11 May 2010Estimating climate sensitivity from 3 million years ago
Johnd, The point that I made is that the forcing from CO2 is additive while the forcing from heat released by using energy is not. Thus the forcing from CO2 grows each year while the energy forcing stays the same. Over time the CO2 forcing greatly exceeds the energy forcing. Heat released this year does not add to heat released next year. CO2, once released into the atmosphere, is essentially permanent. CO2 released next year adds to this years CO2. After a certain period of time the energy forcing becomes negligable compared to the CO2 forcing, even though this year the forcing from energy exceeds this years CO2 forcing. I would not agree with your characterization of the CO2 forcing as "very tiny". One year of CO2 is a small forcing, but we have been emitting CO2 for 150 years. The current CO2 forcing is equal to the difference between current CO2 and pre-industrial CO2. Wikepedia says current CO2 is 389 ppm versus 284 in 1832. Using your numbers that is about 0.4 W/m2 and growing. This is a very large forcing, much greater than the forcing caused by direct heat release (your 0.027 W/m2 for direct energy release). -
scaddenp at 08:44 AM on 11 May 2010Climate Change and the Integrity of Science: a letter to Science
Geo-guy. "One of the issues that climate scientists have not been able to integrate into their models is the relationship of el Nino and global warming trends." This is not true. ESNO features arise with climate models - ie they are an output, not an input of models. There is insufficient skill to use a climate model for prediction of individual ESNO events but that doesnt limit in any way the models ability to predict a 20 year temperature trend. As to complexity of regional weather - heat distribution around the planet is complex that doesnt mean you cant make statement about the global energy balance. If you heat a large pot on the stove, you will get convection patterns that would be extremely hard to model but it doesnt stop the fact the pot will still heat up and boil if there is enough energy at the bottom. -
Geo Guy at 08:44 AM on 11 May 2010Climate Change and the Integrity of Science: a letter to Science
Robhon # 213 - let's just agree to disagree on this issue. My comments re Mann had to do with the process they followed and not to their conclusions. I have yet to find a valid report refuting the critique of M&M on the process and data manipulation carried out by Mann et al. -
Rob Honeycutt at 08:25 AM on 11 May 2010Climate Change and the Integrity of Science: a letter to Science
@Geo Guy... Just checked out your link to the 2004 Richard Muller article regarding McIntyre and McKitrick's critique of Mann's hockey stick. You need to do a little more research here. There are a lot of critiques of the Mc&Mc critique. And this is all older information. There are a long series of papers that have used other measures to come to similar conclusions as Mann (including Huang 2004, Oerlemans 2005, Moberg 2005, Esper 2002, Briffa 2001 and others). -
Geo Guy at 08:13 AM on 11 May 2010Climate Change and the Integrity of Science: a letter to Science
maintain_integrity # 199 & 200 I guess you missed the point of a tid bit - it wasn't to provide any proof but rather simply to show that climate varies widely and that long term cold records in some locations are being broken. Does this mean global warming is not happening? Of course not. Does it say global cooling is happening? Of course not. What it might reflect is the idea that climate change is more complex than many are making it out to be. Prior to the winter, it was predicted that this year would be an el Nino year - warming and drier than usual in the west side of NA, cooler and wetter on the east coast and colder in Europe - all of which happened. One of the issues that climate scientists have not been able to integrate into their models is the relationship of el Nino and global warming trends. Including temperatures that occur during an el Nino episode can have the effect of raising the calculated average for global temperatures. It is same effect a sale of a multi million dollae house in a market will have on average house prices in that market. That is why I feel that a median temperature is more indicative of what is really happening climate wise than average temperatures. As for the NSIDC report, certainly the data at environment Canada's website doesn't reflect a warmer arctic this past winter http://www.climate.weatheroffice.gc.ca/Welcome_e.html One final note, can any one provide a link to any articles describing the role the jet stream has in determining climate? I ask that because where I live, the jet stream can be either north or south of us. The temp difference realized depending on its location can be 15 degrees C. -
scaddenp at 07:56 AM on 11 May 2010Climate Change and the Integrity of Science: a letter to Science
I'd love to see how you get urban heat islands melting glaciers and causing sea level rise. What Mann "forecast" are you referring to? "Forecast" is not especially useful term without knowing the methodology used. You can make pretty good forecasts of a projectile path when fired from gun from physics. You dont get same certainty from statistical models based on past behaviour. -
Geo Guy at 07:52 AM on 11 May 2010Climate Change and the Integrity of Science: a letter to Science
maintain_integrity # 199 & 200 I guess you missed the point of a tid bit - it wasn't to provide any proof but rather simply to show that climate varies widely and that long term cold records in some locations are being broken. Does this mean global warming is not happening? Of course not. Does it say global cooling is happening? Of course not. What it might reflect is the idea that climate change is more complex than many are making it out to be. Prior to the winter, it was predicted that this year would be an el Nino year - warming and drier than usual in the west side of NA, cooler and wetter on the east coast and colder in Europe - all of which happened. One of the issues that climate scientists have not been able to integrate into their models is the relationship of el Nino and global warming trends. Including temperatures that occur during an el Nino episode can have the effect of raising the calculated average for global temperatures. It is same effect a sale of a multi-million dollar house in a market will have on average house prices in that market. That is why I feel that a median temperature is more indicative of what is really happening climate wise than average temperatures. With respect to the NSIDC report, am not sure where they got their data from, however if you look at the Environment Canada's date that covers data from 1840 to the present, their info does not support NSIDC's contention that the Artic was warmer than usual. http://www.climate.weatheroffice.gc.ca/climateData/canada_e.html The above link allows you to access data from some 168 stations located the Canada's east arctic and some 144 from the west Arctic. Not all stations have a full set of data but there are enough for you to be able to identify trends. -
Rob Honeycutt at 07:28 AM on 11 May 2010Climate Change and the Integrity of Science: a letter to Science
@Geo Guy... I did look at the other links but maybe you missed my point. You are using anecdotal information to form conclusions. "Tidbits" are a double edged sword. -
johnd at 07:21 AM on 11 May 2010Climate Change and the Integrity of Science: a letter to Science
tobyjoyce at 04:04 AM, perhaps I need to make it clearer still, these snippets should help. ‣ “... the modelling of time dependent clouds is perhaps the weakest aspect of the existing general circulation models and may be the most difficult task in constructing any reliable climate model” --- Arakawa (WMO,1975) ‣ “It must thus be emphasized that the modeling of clouds is one of the weakest links in the general circulation modeling efforts” --- Charney (NRC,1979) ‣ “Probably the greatest uncertainty in future projections of climate arises from clouds and their interactions with radiation ... even the sign of this feedback remains unknown” --- IPCC (TAR 2001) ‣ “Cloud feedbacks are a primary source of inter-model differences in equilibrium climate sensitivity, with low cloud being the largest contributor” --- IPCC-draft language (2006) This is what the question has, and still pivots on, as I mentioned earlier, as yet remaining unresolved. If you have some evidence that the matter has been resolved, please present it. positive cloud feedback, larger climate sensitivity negative cloud feedback, smaller climate sensitivity -
Stephen Baines at 07:15 AM on 11 May 2010Climate Change and the Integrity of Science: a letter to Science
GeoGuy 204 Re acidity. It's true that SO2 is acidifying and H2SO4 is more acidic than carbonic acid. But there is substantially less of it and it desn't get around much. SO2 has a half life of days in the atmosphere -- what doesn't fall out locally as particles interacts readily with water droplets and quickly rains out. As a consequence, it cannot build up to great concentations and is deposited regionally. Only lakes and streams that are small, dilute and whose watersheds have very low buffering capacities are generally sensitive to acid rain. Lakes that are as alkaline as the ocean (which resemebled a saline lake in chemistry) are not senstive to acid rain - unless you REALLY pound them as has sometimes happened in Eastern Europe. CO2 has a residence time in the atmosphere in years. That means it is well mixed in the atmosphere relatively unvarying in concentration and continuously exchenging with dissolved CO2 in the ocean. The increase in CO2 is felt throughout the whole ocean. Because of CO2, pure droplets of water in the amsophere have a pH of 5.6 (actually lower --that was in the 80's!). SO2 rains out mostly near sources on land and only sporadically. It concentrations have been declining due to controls on emissions. A success story of regulation and the model for cap and trade approaches! NOx (another pollutant that causes acid rains) shows similar characteristics although it is not declining yet. So no, SO2 cannot be the cause of declining pH in the ocean. The other effets you cite are too local in effect as well. The change in pH we see correlates perfectly with what we expect from changes in temp and pCO2 based on equilibrium buffer chemistry. -
J Bowers at 07:15 AM on 11 May 2010Estimating climate sensitivity from 3 million years ago
These other papers are probably relevant to this subject: Palaeoclimate: Global warmth with little extra CO2. Birgit Schneider & Ralph Schneider (2010). http://www.nature.com/ngeo/journal/v3/n1/full/ngeo736.html (3 - 4C once thought to be associated with CO2 at 500 - 600 ppmv therein put at 385 ppmv) "Coupling of CO2 and Ice Sheet Stability Over Major Climate Transitions of the Last 20 Million Years. Tripati et al (December 2009) http://www.sciencemag.org/cgi/content/abstract/1178296 Earth system sensitivity inferred from Pliocene modelling and data. Lunt et al (December 2009) http://www.nature.com/ngeo/journal/v3/n1/abs/ngeo706.html Here’s a chart: http://www.paleo.bris.ac.uk/~ggdjl/conferences/egu2009_ess.pdf High Earth-system climate sensitivity determined from Pliocene carbon dioxide concentrations. Pagani et al (December 2009) http://www.nature.com/ngeo/journal/v3/n1/abs/ngeo724.html Atmospheric CO2 concentrations during ancient greenhouse climates were similar to those predicted for A.D. 2100. Breecker et al (October 2009) http://www.pnas.org/content/107/2/576 -
Geo Guy at 07:08 AM on 11 May 2010Climate Change and the Integrity of Science: a letter to Science
robhorn # 198 - interesting link - you showed the month of April, if you look at earlier months you will see a much different story. December, 2009 http://climate.rutgers.edu/snowcover/chart_anom.php?ui_set=1&ui_region=nam&ui_month=12
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