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archiesteel at 08:19 AM on 27 December 2010Lindzen and Choi find low climate sensitivity
As an off-topic note, it would be nice to be able to vote (or at least register our agreement/disagreement) on comments. Some sort of "real ID" registration would also help weed out sockpuppet accounts (not aiming this at anyone in particular, mind you). Skeptical Science 2.0, anyone? ;-) -
archiesteel at 08:16 AM on 27 December 2010Lindzen and Choi find low climate sensitivity
@RW1: sure, you can start by responding to chris at #222. I'm also curious to see if you will acknowledge you were wrong when you said: "If this is true, then power from the Sun and power from CO2 cannot both be expressed in W/m^2 as they are." scaddenp and I both revealed your misconceptions about what the W/m² figure means. Will you admit you were wrong about this, and thus about the 4 W/m² having to be cut in half to calculate sensitivity? A simple yes or no will suffice. -
scaddenp at 08:01 AM on 27 December 2010Lindzen and Choi find low climate sensitivity
"If this is true, then power from the Sun and power from CO2 cannot both be expressed in W/m^2 as they are." Of course they can. The forcing term is global annual average. The energy flux (NOT power - please note that this term is normally used in context of energy transformation) produces the same temperature rise without feedbacks. See the chapter in the IPCC on why you calculate forcings in this way and evidence that it can used for arithmetic. However, for considering feedbacks, the energy flux is different spatially, temporally, and spectrally between solar and GHG (and aerosols and albedo if it comes to that). -
RW1 at 08:01 AM on 27 December 2010Lindzen and Choi find low climate sensitivity
archiesteel, When someone offers a cogent counter-argument and you don't respond, then you have been successfully rebutted. I'm hardly the first one to note this here, either. I know I have missed a few things and haven't responded to everything. Again, I stated that in the middle of the thread somewhere. Please point me to the specific counter-argument presented that I have failed to address and I'll respond to it. -
Daniel Bailey at 08:00 AM on 27 December 2010Lindzen and Choi find low climate sensitivity
Re: RW1 (274, 276 et al) You said:archiesteel, "I'm just pointing out that your arguments have all been rebutted. No, you're just declaring they have been successfully rebutted.
Thanks for clarifying that. Other than being argumentative, do you still have a purpose in continuing this conversation? After all, you point out that your position has been successfully rebutted. This site contains a plethora (lovely word, that) of science-based information substantiated by links to actual peer-reviewed sources for those interested in learning about climate science. Even, for example, on working out climate sensitivity from satellite information (the subject of this post the nature of which this conversation abandoned any pretense at following long ago). Usually I'm the one catching flack for using the appellation "dude". :) The Yooper -
archiesteel at 07:57 AM on 27 December 2010Is it safe to double atmospheric Carbon Dioxide over a 200 year period?
@anastrophe: please show me proof that the many recent extreme weather events have not been made worse by the increase of energy in the global weather system caused by AGW. Thanks. BTW, the Intermediate version of the "It's not bad" argument provides ample sources for you to educate yourself. @gallopingcamel: a pollutant is not simply determined by toxicity, but also by the harm it causes in large concentrations. Increased CO2 is harmful, and won't by itself help plant growth. As for the net effect of AGW, experts may disagree on details, but they pretty much all agree it will be bad. -
archiesteel at 07:53 AM on 27 December 2010Lindzen and Choi find low climate sensitivity
@RW1: "No, you're just declaring they have been successfully rebutted." When someone offers a cogent counter-argument and you don't respond, then you have been successfully rebutted. I'm hardly the first one to note this here, either. Therefore, I am simply pointing out something everyone already recognizes. "Whatever, dude. If you're not going to specifically address anything in a way that facilitates any genuine scientific give and take discussion, I'm not going to respond anymore." Go ahead, "dude", it'll make my job of pointing out errors in your arguments a lot easier. :-) -
gallopingcamel at 07:50 AM on 27 December 2010Is it safe to double atmospheric Carbon Dioxide over a 200 year period?
anastrophe (@59), You make excellent points. Like you I want to improve the environment by limiting the pollution of our air and water. However, I don't see CO2 as a "Pollutant" given that all plants would die without it. From basic physics it is clear that CO2 concentrations in the atmosphere have an effect on radiative heat transfer but the experts are still arguing about the net effect on global climate after "feedbacks" are taken into account. -
anastrophe at 07:45 AM on 27 December 2010Is it safe to double atmospheric Carbon Dioxide over a 200 year period?
@dhogaza, you offer nothing but rote dismissal of my comments. is it really necessary for you to attempt to dismiss my thoughts, rather than actually addressing them? @archiesteel, i just skimmed the article you directed me to. it has a lot of "might" and "may" and "could" to it; it provides no science to back up the anecdotal claims it makes. again, show me the proof that the small warming that has occurred has actually caused harm. not speculations about what might, may, could happen if we warm further. evidence of harm that has occurred. there is none as yet. only anecdote. and i'll note that the word alarmism well predates your colloquial claim that it's used to denigrate 'those who understand the scientific consensus'. show me what harm has occurred. show me how screaming that the sky if falling is useful. -
RW1 at 07:43 AM on 27 December 2010Lindzen and Choi find low climate sensitivity
archiesteel, "I'm just pointing out that your arguments have all been rebutted. No, you're just declaring they have been successfully rebutted. You also keep repeating obvious things I already know, such as the increase from 2xCO2 will be in addition to (or on top of) seasonal and orbital eccentricity cycles, each of which average out and don't contribute to long term warming. Whatever, dude. If you're not going to specifically address anything in a way that facilitates any genuine scientific give and take discussion, I'm not going to respond anymore. -
archiesteel at 07:38 AM on 27 December 2010Is it safe to double atmospheric Carbon Dioxide over a 200 year period?
@gallopingcamel: looking at past values of CO2 is useless if you don't adjust it for lower solar input, as was the case when it was in the high end of that range. The last time CO2 concentrations were this high with a similar solar output, temperatures were 5 to 7 degrees warmer than today. So the answer to the question is really "NO". The "CO2 lags temperature" argument is also junk, as shown elsewhere on this site. Also, it would be nice if you admitted you were wrong about increased atmospheric CO2 automatically being good for plants. -
gallopingcamel at 07:34 AM on 27 December 2010Is it safe to double atmospheric Carbon Dioxide over a 200 year period?
I was trying to answer the question "Is it safe to double atmospheric Carbon Dioxide over a 200 year period" but rather than get bleeped, I will try a different approach. Atmospheric carbon dioxide concentrations have varied over a wide range since life appeared on land. For the sake of argument I suggest a range of 190 to 7,000 ppm, although the error bars at the high end leave plenty of room for debate. Modern CO2 levels are quite close to the low end of the range and even with a doubling will remain at levels that have been well tolerated by living things over hundreds of millions of years through both climate optimums and ice ages. So the answer to the question is "YES". The arguments for CO2 driven catastrophe arise from an inclination to see only negative consequences from changing conditions as if the status quo represents some kind of "golden age". The "fingerprinter" is guilty of making all kinds of statements that are contrary to what the science tells us. For example: "The first place to look is of course the paleoclimate record. Over the last several decades of research, the sensitivity of the climate system to changes in carbon dioxide has been established through ice core samples and other proxy climate indicators." The ice core records such as Vostok and GISP/GRIP show no such thing. To the contrary they show the sensitivity of carbon dioxide concentrations in the atmosphere to changing temperatures. -
archiesteel at 07:24 AM on 27 December 2010Lindzen and Choi find low climate sensitivity
@RW1: "You're not engaging in scientific argument - just shouting down anyone who presents any contradictory information and repeating things you've already concluded." I'm not shouting down anyone, I'm just pointing out that your arguments have all been rebutted, and yet you continue repeating them as if saying a false thing often enough would make it true. Unlike you, I'm more than welcome to be shown wrong about AGW. I don't *want* it to be true. However, I must conced when faced with the mountain of evidence supporting it, and the absence of evidence supporting the contrarian view. That's what science is about, not your purposefully-confusing attempts at minimizing the reality of AGW in order to satisfied you preconceived, politically-motivated opinions. "If that is all you're interested in doing, then why even participate on this site - let alone this thread?" Because that's not what I'm interested in doing. I'm interested in honest scientific debate, not whatever it is that you're doing. -
archiesteel at 07:20 AM on 27 December 2010Is it safe to double atmospheric Carbon Dioxide over a 200 year period?
@Anastrophe, I refer you to the It's not bad for a few examples on how a 0.15C rise per decade is dangerous. BTW, it's "alarmism" to be prepared to deal with bad stuff, it's survival. "Alarmism" is the term contrarians use to denigrate those who understand the scientific consensus. The truth of the matter is that alarmism is much less of a threat right now than is apathy. -
RW1 at 07:17 AM on 27 December 2010Lindzen and Choi find low climate sensitivity
archiesteel (RE: 273), You're not engaging in scientific argument - just shouting down anyone who presents any contradictory information and repeating things you've already concluded. If that is all you're interested in doing, then why even participate on this site - let alone this thread? -
johnkg at 07:14 AM on 27 December 2010An overview of Greenland ice trends
#38. Camburn. A more recent paper that cites the one you mentioned and has a 168 year trend. http://journals.ametsoc.org/doi/abs/10.1175/2009JCLI2816.1 In contrast to the 1920s warming, the 1994–2007 warming has not surpassed the Northern Hemisphere anomaly. An additional 1.0°–1.5°C of annual mean warming would be needed for Greenland to be in phase with the Northern Hemispheric pattern. Thus, it is expected that the ice sheet melt rates and mass deficit will continue to grow in the early twenty-first century as Greenland’s climate catches up with the Northern Hemisphere warming trend and the Arctic climate warms according to global climate model predictions. -
archiesteel at 07:14 AM on 27 December 2010An overview of Greenland ice trends
@Camburn: since you are citing an AGU study, I'm sure you also agree with the AGU's official position on AGW, right? Here it is, in case you weren't awayre of it: "The Earth's climate is now clearly out of balance and is warming. Many components of the climate system--including the temperatures of the atmosphere, land and ocean, the extent of sea ice and mountain glaciers, the sea level, the distribution of precipitation, and the length of seasons--are now changing at rates and in patterns that are not natural and are best explained by the increased atmospheric abundances of greenhouse gases and aerosols generated by human activity during the 20th century." -
archiesteel at 07:05 AM on 27 December 2010It's Pacific Decadal Oscillation
@NETDR: "Is this divide and conquer time ?" Just stick to making rational arguments that are on-topic and you won't have any problems. For isntance, there is no evidence AFAIK that the PDO and the LIA are directly related, therefore trying to link the two in some sort of "grand unified denier theory" is off-topic. The truth is that contrarians are forced to resort to the logical fallcy known as "changing the subject," because they do not have arguments that withstand scrutiny, and therefore are forced to flee to another topic whenever they are confronted with the weakness of their position. My personal suggestion to you is that, if you don't like the moderation on this site, then just stop commenting. Maybe then we'll be able to have more constructive discussion, such as what we should actually do to mitigate the very real effects of AGW. -
archiesteel at 06:59 AM on 27 December 2010Lindzen and Choi find low climate sensitivity
@RW1: "Just repeating generalities doesn't make them true." They're not generalities, they're the actual current level of scientific understanding on the matter of AGW. You have failed so far to demonstrate why we should believe in a unreviewed theory that runs counter to current science *and* observations. "If you don't desire to or not able to engage in genuine scientific discussion in this thread, then why participate?" I am both able and eager to engage in genuine scientific discussion, but apparently you're not, since you continue to latch on a dubious theory while ignoring the very thorough counter-arguments presented to you. As I said earlier, you're not really interested in learning the truth, but simply "muddy the waters", i.e. create confusion and force people to spell out obvious scientific truths in order to bog down the scientific debate. Hey, when even self-avowed skeptics disagree with your argument, you know you have a problem. -
Camburn at 06:45 AM on 27 December 2010An overview of Greenland ice trends
You would be better served to include at least a 100 year trend analysis. There is data for the period. As an example, here is data in ref to temperatures: http://meteo.lcd.lu/globalwarming/Chylek/greenland_warming.html -
dhogaza at 06:30 AM on 27 December 2010Is it safe to double atmospheric Carbon Dioxide over a 200 year period?
Anastrophe's post is nothing but a rote recapitulation of standard denialist dogma. Do we really need it here? Can't we at least have some creative skepticism? -
NETDR at 06:14 AM on 27 December 2010It's Pacific Decadal Oscillation
It is almost impossible to post coherent arguments on skepticalscience.com because all arguments slide between threads and part of every response is O T. The so called skeptical arguments are straw-men which don't cover my reasons for not believing in catastrophe at all. Consequently my posts are O T wherever I post them Ocean currents can not cause overall arming but they can cause short term [20 - 30 year like the 78 – 98 ] warming which fools the scientist into thinking there is a bigger trend than there is. Solar variation did not cause the 78 – 98 warming but it can cause the 1880 to 2010 trend when long term positive feedback is factored in. Some treat positive feedback as if it only operates on CO2 caused warming but no scientist really believes that. By breaking the two arguments apart they are both O T on two different threads. Is this divide and conquer time ?Moderator Response: If you would bother to read the Climate Time Lag post to which you were pointed, you would learn why your contention about solar contribution is wrong. -
RW1 at 06:13 AM on 27 December 2010Lindzen and Choi find low climate sensitivity
archiesteel, Just repeating generalities doesn't make them true. If you don't desire to or not able to engage in genuine scientific discussion in this thread, then why participate? -
anastrophe at 06:05 AM on 27 December 2010Is it safe to double atmospheric Carbon Dioxide over a 200 year period?
this article actually doesn't address what it claims to address. in the argument 'is it safe', this article merely addresses whether or not increased CO2 causes warming - not whether that warming is safe or unsafe. i am a skeptic. the holes in the alarmism arguments are large enough to drive a CO2 belching truck through. there has been no verified, demonstrable evidence yet presented that there have been any harmful effects due to the less than one degree C of global warming over the last century. there has been considerable anecdotal evidence suggested. much of it wrong. we here in the US were relentlessly warned after hurricane katrina that this was a sign of 'things to come'. we all know how that turned out. rising sea levels have not been empirically demonstrated to date. anecdotally yes. south sea islands going under? no. subsidence, yes. there has been no statistically significant increase in global temperature in the last *fifteen years* - all while china has increased its belchings of CO2 by many orders of magnitude. no, all i ask is that climate "science* give me something more concrete than ridiculous computer models with no basis in reality. all i ask is actual, verifiable PROOF that harm has occurred. now, does my skepticism mean i'm against reducing dependence on petroleum, that i'm against clean air? not in the slightest. it's likely that oil will run out someday. as a feedstock for a huge number of extremely important products that have made life better for all humans, i'm in favor of conserving petroleum for uses more constructive than driving about on a sunday afternoon. we need power to run our modern world - and we need to find alternatives. what i am against is extreme policies that can harm just as many people as global warming is claimed may be harmed. alarmism is harmful in itself. it does not advance the science or the argument. running about, screaming that the sky is falling, is not having the effect the promulgators desire. encourage conservation. work on creating the ultimate solar panel. be constructive, rather than alarmist, and you'll accomplish a hell of a lot more, and alienate a hell of a lot fewer people. -
archiesteel at 05:50 AM on 27 December 2010Lindzen and Choi find low climate sensitivity
@RW1: I'm sorry, I wasn't clear enough. I meant to ask why, considering you agree that CO2 is an additional forcing, do you keep trying to insinuate that the CO2 effect is not significant, when the science clearly indicates it will be, and observations confirms what the science says? This is the crux of it: we know it is warming, and we know why it's warming. That warming is within projections that indicate an increase of about 3C (including feedbacks) for a doubling of CO2. So far you have failed to clearly demonstrate *anything* that challenges this, relying on a single source that has not been peer-reviewed, and which to makes some glaring mistakes (if we are to believe your interpretation - the fault may lie there instead). Again, please stop wasting everyone's time. -
RW1 at 05:31 AM on 27 December 2010Lindzen and Choi find low climate sensitivity
archiesteel, Also, why won't you acknowledge the fact that the seasonal change represents a cycle, while CO2 forcing represents a supplementary increase... Because I already have acknowledged it - multiple times in this thread I might add. I'm well aware of it, and I have been long before I ever posted anything here. I'm trying to now take things in a step by step basis. I'm using the information from that website because it's empirically derived from satellite data and it makes the fewest assumptions about how the climate system behaves globally or hemispherically - each of which reveals critically important characteristics. Also, the Lindzen and Choi feedback study has been criticized as only being localized in the tropics, where as this analysis is global and gets roughly the same sensitivity. If you're not interested, then don't participate and continue to believe whatever you want. -
archiesteel at 05:11 AM on 27 December 2010Lindzen and Choi find low climate sensitivity
@RW1: why do you keep citing the same website as reference? Is that your only source? Also, why won't you acknowledge the fact that the seasonal change represents a cycle, while CO2 forcing represents a supplementary increase, i.e. raising the "AVG" value of those irrelevant graphs? In short, why do you keep wasting our time? You're not going to convince anyone here with marginal theories that haven't been published and/or peer-reviewed, and which run counter to actual observations. You're also not going to convince those who are still learning the science with your convuluted, purposefully confusing arguments. The only people you are going to "convince" are those who have already decided they don't believe in AGW, i.e. who seek positive reinforcement of their preconcieved opinions. This begs the question, then: why are you doing this? -
chris at 04:56 AM on 27 December 2010Is it safe to double atmospheric Carbon Dioxide over a 200 year period?
It’s probably futile to draw your attention yet again to the science that informs our understanding on these issues gallopingcamel, but in the seasonal spirit let’s have another go.gallopingcamel:”You don't need university researchers to tell you this kind of thing. Enhancing the CO2 in greenhouses has been a common practice for decades.”
Sadly, that only works under conditions of optimal water and fertilization supplementation. In the real world that’s not how the vast majority of food crops are grown. If you were to properly assess the FACE experiments that aim to characterize the effects of CO2 supplementation under field conditions, the picture isn’t so rosy: S. P. Long, et al (2006) Food for Thought: Lower-Than-Expected Crop Yield Stimulation with Rising CO2 Concentrations Science 312, 1918-1921 abstract A. D. B. Leakey et al. (2009) Elevated CO2 effects on plant carbon, nitrogen, and water relations: six important lessons from FACE J. Exp. Botany 60, 2859-2876“More broadly, the stimulation of seed yield in response to growth in elevated [CO2] is ~50% lower in FACE experiments than in enclosure studies for the world’s four most important crops (Long et al., 2006; Ainsworth, 2008; Ainsworth et al., 2008a). With the caveat that FACE experiments have been limited in number and geographical coverage, the much lower elevated [CO2] fertilization factor on yield observed under agronomicaly relevant conditions has potentially serious implications for projections of world food supply……………. Most important though will be understanding why our major food crops fail to achieve the improved production under elevated [CO2] that can be achieved in protected environments and by some non-crop species.”
J.A. Langley & J. P. Megonigal (2010) Ecosystem response to elevated CO2 levels limited by nitrogen-induced plant species shift Nature 466, 96–99 abstract This reiterates that any [CO2] effect requires enhanced N (nitrogen) nutrient as is well known, but the combined effects of [CO2]/N are likely to be counterproductive with respect to plant growth in natural ecosystems due to CO2/N-induced shifts in plant species. So natural ecosystems may respond poorly to enhanced [CO2] due to water and nutrient limitation and species shifts. In other words the terrestrial ecosystem is likely increasingly to falter as a sink to "mop up" large amounts of enhanced anthropogenic [CO2]. Managed agricultural production may cope with enhanced [CO2] but is likely to become more expensive to support due to nutrient and water limitations, as indicated by FACE studies (e.g. as in the first two papers above).gallopingcamel: ” However, you are in error to link desertification to increased temperatures. It is falling temperatures that increase desertification, while rising temperatures cause increased precipitation”
Wrong. The predictions on changing precipitation patterns in a warming world are borne out by real world observations. The latitude band from around the equator to near 30 oN has become drier as the Earth has warmed during the 20th century, much as predicted, and will continue to do so. This latitudinal band of reduced precipitation will widen as the Earth continues to warm (and so Amazonia, for example, is expected to dry progressively towards the South as the Earth warms). The higher latitudes (especially above 50o N and below 10 o) have seen enhanced precipitation. Global warming and shifts in precipitation regimes is expected (and already observed) to lead to amplification of extreme precipitation events (one could cite more papers on this, but Allen et al. 2008 is a decent starting point). In other words those parts of the world that are water-limited are becoming more susceptible to drought as global warming proceeds…those areas of the world that don’t need more rain (higher latitudes) are getting more: X. Zhang et al. (2007) Detection of human influence on twentieth-century precipitation trends Nature 448, 461-465 abstract RP Allen et al. (2008) Atmospheric warming and the amplification of precipitation extreme Science 321, 1481-1484 abstractModerator Response: Since there already is a history of comments on this topic on the thread CO2 Is Not a Pollutant, how about everybody respond over there. -
RW1 at 04:49 AM on 27 December 2010Lindzen and Choi find low climate sensitivity
Eric, "New power flux is added which causes an increase to T+delta, "gain" is much higher. That's because "gain" is not a constant as KR explained in 210." The reason I ask is because I think you are saying that the gain increases as temperature and surface power increases. Actually, the gain decreases as radiative forcing and surface power increases. This is very clear from the graphs, where the gain is out of phase with solar input: http://www.palisad.com/co2/eb/g/gain.png This is true in both hemispheres as well: http://www.palisad.com/co2/eb/nh/gain.png http://www.palisad.com/co2/eb/sh/gain.png Do you see how/why this clearly illustrates negative feedback? That is as radiative forcing and power increases, the proportional amount of surface power increase is reduced, and as radiative forcing and power decreases, the proportional amount of surface power increases. This means that increases in radiative forcing and temperature are being opposed rather than reinforced by the climate system. -
archiesteel at 04:16 AM on 27 December 2010Is it safe to double atmospheric Carbon Dioxide over a 200 year period?
@gallopingcamel: as others have pointed out, it's not just as simple as doubling CO2. In a greenhouse you control temperature, moisture and the amount of nutrients the plants get. You are the perfect example of the old saying, "a little knowledge is dangerous." I suggest you learn more about growing plants (I myself have spent a lot of time working in a greenhouse at my sister's farm) before pushing the myth that "increased atmospheric CO2 will have a beneficial effect on plant growth" when there is *no* indication this would be the case.Moderator Response: As GP perfectly well knows, there are other threads that are appropriate for his repetition of these arguments. Deletions will commence soon. -
archiesteel at 04:10 AM on 27 December 2010Renewable Baseload Energy
An interesting article on use of microgeneration in developing countries: African Huts Far From the Grid Glow With Renewable Power -
muoncounter at 03:57 AM on 27 December 2010It's freaking cold!
An interesting take on the extreme winter by a weather guy in 26 Dec NY Times: As global temperatures have warmed and as Arctic sea ice has melted over the past two and a half decades, more moisture has become available to fall as snow over the continents. So the snow cover across Siberia in the fall has steadily increased. The sun’s energy reflects off the bright white snow and escapes back out to space. As a result, the temperature cools. When snow cover is more abundant in Siberia, it creates an unusually large dome of cold air next to the mountains, and this amplifies the standing waves in the atmosphere ... He goes on to explain how this forces the jet stream into a more N/S configuration, resulting in deeper, wetter cold fronts. Which is as reported here and here and shown below.Similar results published in JGR: This causes a continental-scale winter cooling reaching −1.5°C, with more than 3 times increased probability of cold winter extremes over large areas including Europe. Our results imply that several recent severe winters do not conflict the global warming picture but rather supplement it, being in qualitative agreement with the simulated large-scale atmospheric circulation realignment.
Moderator Response: [muoncounter] Note: original image was from intellicast and updated daily. Conditions referred to here occurred in late Dec 2010; jet stream map now shown for 12/26/10 from archive at http://squall.sfsu.edu/crws/archive/jetsat_arch.html -
muoncounter at 03:28 AM on 27 December 2010Is it safe to double atmospheric Carbon Dioxide over a 200 year period?
#53: "Enhancing the CO2 in greenhouses has been a common practice" And we are comparing the artificial, closed environment of commercial greenhouses to the open atmosphere because ...? Does it occur to you that moisture content in a commercial greenhouse is also controllable? "in error to link desertification to increased temperatures." Or not: "more arid conditions" "Increased drought frequency will likely cause major changes in vegetation cover." "An Australian study offers further confirmation of the climate change phenomenon – arid regions are indeed becoming drier and higher rainfall regions wetter" Interestingly, there seems to be reports of both extreme drought and floods. Are we up to 7 out of 10 yet? -
Philippe Chantreau at 02:42 AM on 27 December 2010Is it safe to double atmospheric Carbon Dioxide over a 200 year period?
It's also worth mentioning that commercial greenhouses using CO2 enriching maintain between 800 to 1200 ppm CO2 content. If we have to get there to see any "benefit" we'll end up with quite an interesting geo-engineering experience, especially if it's done in just another few decades. -
Daniel Bailey at 02:29 AM on 27 December 2010Is it safe to double atmospheric Carbon Dioxide over a 200 year period?
Re: gallopingcamel You need to read Dai et al 2010, then. Hope your Christmas was merry, The Yooper -
gallopingcamel at 02:10 AM on 27 December 2010Is it safe to double atmospheric Carbon Dioxide over a 200 year period?
archiesteel (#48), According to the FACE experiment (Nicolas School of the Environment), CO2 does make plants grow more. When CO2 concentrations are increased, plants grow faster until scarcity of some other nutrient intervenes. You don't need university researchers to tell you this kind of thing. Enhancing the CO2 in greenhouses has been a common practice for decades. If you are right, global temperatures will rise as a result of doubling the CO2 concentration in the atmosphere. However, you are in error to link desertification to increased temperatures. It is falling temperatures that increase desertification, while rising temperatures cause increased precipitation. -
Daniel Bailey at 01:45 AM on 27 December 2010Ice isn't melting
Over on Neven's Arctic Sea Ice blog, a reader has done an analysis of the Arctic sea ice loss, with a log-fit (R2=0.933253) showing 2011 as the last full-ice year:So much for the "recovery". The Yooper
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muoncounter at 01:10 AM on 27 December 2010Is it safe to double atmospheric Carbon Dioxide over a 200 year period?
#46: "The plants are going to love it but nobody listens the them ... " Nice of gc to entertain with his Lorax imitation.Unfortunately, messing with Mother Nature can produce surprising results: The direct, physiological response of plants to elevated CO2 generally acts to weaken the earth’s hydrologic cycle by lowering transpiration rates across the globe. Lowering transpiration alone would tend to enhance soil moisture. However, reduced recirculation of water in the atmosphere, which lowers precipitation, leads to more arid conditions overall (simulated global soil moisture decreases by 1%), particularly in the Tropics and midlatitudes. And if altering the hydrologic cycle isn't a big enough gamble, here's evidence for another unintended consequence: Elevated levels of atmospheric carbon dioxide (CO2), a consequence of anthropogenic global change, can profoundly affect the interactions between crop plants and insect pests and may promote yet another form of global change: the rapid establishment of invasive species. So that could add famine, locusts and probable cattle diseases to our list. Just how many Biblical-style plagues do the deniers consider 'safe'?
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Riccardo at 00:25 AM on 27 December 2010Is it safe to double atmospheric Carbon Dioxide over a 200 year period?
it sounds very much like the cheapest and most reliable nightmare. -
John Brookes at 21:22 PM on 26 December 2010Is it safe to double atmospheric Carbon Dioxide over a 200 year period?
To be fair to the skeptics, reducing our dependence on fossil fuels will be difficult. It won't be the end of civilisation as we know it, which is what skeptics think. But we do need to make the judgement, "Are the risks of global warming sufficient to justify the cost of abandoning fossil fuels?" I think it is worth it, but others may differ. It does bug me when they argue that global warming isn't happening, and our CO2 emissions aren't causing it. -
archiesteel at 18:40 PM on 26 December 2010Lindzen and Choi find low climate sensitivity
@RW1: "The graph clearly shows the solar power fluctuting by about 20 W/m^2 from perihelion in January to aphelion in July" Who cares? It's a fluctuation, as you point out yourself. The additional 4 W/m³ for a doubling of CO2 is an actual increase (and raises temperatures in both seasons). Seriously, go read a book or something. -
sailrick at 18:38 PM on 26 December 2010Is it safe to double atmospheric Carbon Dioxide over a 200 year period?
"Small uncertainties in the conventional science are used to reinforce the notion that doubling atmospheric carbon dioxide is entirely safe." Not only that, but skeptics want us to think doing something about climate change will be unsafe. -
archiesteel at 18:37 PM on 26 December 2010Lindzen and Choi find low climate sensitivity
@RW1: "If this is true, then power from the Sun and power from CO2 cannot both be expressed in W/m^2 as they are." Sure they can. The fact they have different signatures doesn't mean they can't all be reduced to relative W/m² values. RW1, it's clear you have some serious issues understanding simple scientific fact. Rather than waste everyone's time here, I suggest you start taking science classes (and pay attention, this time). -
archiesteel at 18:32 PM on 26 December 2010Greenland ice mass loss after the 2010 summer
@Camburn: "This is interesting as the ice loss of present does not seem to be much different than the ice loss from the 30's and 40's." You should actually read the articles you link to. From the article: "Their evidence reinforces the belief that glaciers and other bodies of ice are exquisitely hyper-sensitive to climate change and bolsters the concern that rising temperatures will speed the demise of that island's ice fields, hastening sea level rise." "The fact that recent changes to Greenland's ice sheet mirror its behavior nearly 70 years ago is increasing researchers' confidence and alarm as to what the future holds. Recent warming around the frozen island actually lags behind the global average warming pattern by about 1-2 degrees C but if it fell into synch with global temperatures in a few years, the massive ice sheet might pass its “threshold of viability” – a tipping point where the loss of ice couldn't be stopped." -
archiesteel at 18:26 PM on 26 December 2010Is it safe to double atmospheric Carbon Dioxide over a 200 year period?
@gallopingcamel: simply increasing CO2 won't make plants grow more. I don't think plants are too keen on increased temperatures and desertification. That's not what I heard from the grapevine. Yes, the actual grapevine. -
archiesteel at 18:22 PM on 26 December 2010It's cooling
@Chris: "What do you make of that?" Uh...that it's utter nonsense? Number of facts the person got wrong: 1) We are *not* in a cooling trend 2) There have been more record hot temperatures than record cold temperatures 3) There is a difference between science and how the media reports it: compounding the two is an illogical thing to do 4) Global Warming doesn't mean it's going to get warmer everywhere all the time 5) It is neither proven nor obvious that the world isn't warming 6) Other long-term factors are not currently affecting climate to a greater degree than CO2 This person you were talking to bases its entire argument on faulty assumptions and outright falsehoods. -
Chris3699 at 17:14 PM on 26 December 2010It's cooling
In a recent debate I had with someone they offered this: "I would like to comment on Global Warming. Makes me smile when I hear Global warmer’s these days dismissing the third year of record cold temperatures as, “Just weather” and the big picture is what really counts! They are of course exactly correct in saying this, it’s what reasonable people have been saying all along, but rest assured that global warmers have been forced into the position they find themselves in. Before the record cold set in every story concerning a shortage of rainfall, lack of snow on the Iditarod trail, a heat wave anywhere, etc, etc, was all linked to the rapped and unstoppable effects of man made global warming. Before the cooling trend every story that could possibly be linked to the immediate affects of AGW, was. The fact is that the world is not warming, everyone knows this, it’s obvious AND it’s proven but let us be extremely generous in this Christmas season and say, for the sake of argument, that yes man kind’s production of CO2 gas can heat the earth. Then we would have to say at this point that there are other factors also affecting the earth’s temperature and that very likely CO2 gas is a minor factor easily made insignificant by the natural forces of nature." What do you make of that? -
gallopingcamel at 17:06 PM on 26 December 2010Is it safe to double atmospheric Carbon Dioxide over a 200 year period?
Ooops! Single malt scotch can affect one's grammar. What I meant was: "The plants are going to love it but nobody listens to them for fear of being dressed in a straitjacket." -
gallopingcamel at 17:02 PM on 26 December 2010Is it safe to double atmospheric Carbon Dioxide over a 200 year period?
Someone needs to speak out in favor of doubling the CO2 concentration. The plants are going to love it but nobody listens the them for fear of being dressed in a straitjacket. If I believed that doubling the CO2 concentration would cause a significant increase in global temperatures I would sell my electric car and buy a really large SUV. Here's wishing you all peace and prosperity in 2011 so that you can increase your carbon footprints.Moderator Response: [muoncounter] Gratuitous cheap shots will get you nowhere. -
RW1 at 16:56 PM on 26 December 2010Lindzen and Choi find low climate sensitivity
Eric, "Each added 1 W/m^2 of power from the sun is equivalent to each added 1 W/m^2 of power from CO2. Feedback doesn't matter in the previous statement." Do we also agree that power from the Sun and power from CO2 are both "forcing" the climate system?
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