# brazil84's Global Warming Thread **URL:** \ **Category:** Great Debates\ **Created:** [December 12, 2007, 2:16am UTC](https://boards.straightdope.com/t/brazil84s-global-warming-thread/429693 "2007-12-12T02:16:11Z")\ **Posts on this page:** 20\ **Page:** 7
**Author:** ![brazil84](https://avatars.discourse-cdn.com/v4/letter/b/8491ac/32.png) [@brazil84](https://boards.straightdope.com/u/brazil84)\ **Post date:** [December 18, 2007, 1:06pm UTC](https://boards.straightdope.com/t/brazil84s-global-warming-thread/429693/121 "2007-12-18T13:06:21Z")
[QUOTE=jshore] I don’t understand what you mean by dominating. But, let me answer the question this way: When CO2 levels are remaining fairly constant while the Milankovitch orbital cycles are causing the sunlight distribution to change (and thus causing ice sheets to grow or shrink) then, yes, the forcing due to the latter can be larger than the forcing due to the former. In any given situation, you have to compare the radiative forcings of each thing that is happening. [/QUOTE] Thank you. Of course it would be very interesting to run some actual numbers. But intuitively, it seems a little odd that the Milankovitch forcing gives the climate a little nudge on the way up but grabs it around the neck on the way down. ---
**Author:** ![jshore](https://avatars.discourse-cdn.com/v4/letter/j/b5e925/32.png) [@jshore](https://boards.straightdope.com/u/jshore)\ **Post date:** [December 18, 2007, 1:20pm UTC](https://boards.straightdope.com/t/brazil84s-global-warming-thread/429693/122 "2007-12-18T13:20:10Z")
[QUOTE=brazil84] Thank you. Of course it would be very interesting to run some actual numbers. But intuitively, it seems a little odd that the Milankovitch forcing gives the climate a little nudge on the way up but grabs it around the neck on the way down. [/QUOTE] I lost you. Why do you say it does this? ---
**Author:** ![brazil84](https://avatars.discourse-cdn.com/v4/letter/b/8491ac/32.png) [@brazil84](https://boards.straightdope.com/u/brazil84)\ **Post date:** [December 18, 2007, 1:25pm UTC](https://boards.straightdope.com/t/brazil84s-global-warming-thread/429693/123 "2007-12-18T13:25:54Z")
[QUOTE=jshore] I lost you. Why do you say it does this? [/QUOTE] Think about it for a minute. You seem to be saying that the Milankovitch cycle alone does not cause temperature to rise. Instead, it also triggers a feedback loop that involves CO2. By analogy, it’s like pushing a ball that then rolls from a higher position to a lower position. That’s all well and good, but it seems odd that when the Milankovitch force turns in the opposite direction, the ball promptly rolls back uphill, so to speak. You would need to do the math to see if it works, but as I say, it’s intuitively troubling to me. ---
**Author:** ![jshore](https://avatars.discourse-cdn.com/v4/letter/j/b5e925/32.png) [@jshore](https://boards.straightdope.com/u/jshore)\ **Post date:** [December 18, 2007, 3:14pm UTC](https://boards.straightdope.com/t/brazil84s-global-warming-thread/429693/124 "2007-12-18T15:14:07Z")
[QUOTE=brazil84] Think about it for a minute. You seem to be saying that the Milankovitch cycle alone does not cause temperature to rise. Instead, it also triggers a feedback loop that involves CO2. By analogy, it’s like pushing a ball that then rolls from a higher position to a lower position. That’s all well and good, but it seems odd that when the Milankovitch force turns in the opposite direction, the ball promptly rolls back uphill, so to speak. You would need to do the math to see if it works, but as I say, it’s intuitively troubling to me. [/QUOTE] I don’t understand why you think one direction is “downhill” and the other is “uphill”. And, just to be clear, the feedback loop operates in both directions. Actually, I don’t even think the ball analogy is very good. There is not really an instability that I can tell. (There does seem to be some difference between the warming and cooling directions because ice sheets can probably break up faster than they can build up…but I don’t think either way should be thought of as unstable. Again, the effect of the CO2 feedback loop is to magnify the change in temperature…and apparently also to link the two hemispheres…not to cause a true instability.) ---
**Author:** ![aptronym](https://avatars.discourse-cdn.com/v4/letter/a/e47774/32.png) [@aptronym](https://boards.straightdope.com/u/aptronym)\ **Post date:** [December 18, 2007, 7:51pm UTC](https://boards.straightdope.com/t/brazil84s-global-warming-thread/429693/125 "2007-12-18T19:51:29Z")
[QUOTE=jshore] I lost you. Why do you say it does this? [/QUOTE] I’m guessing because he’s reading the ice cores backwards. I think he’s looking at a graph where the x-axis is depth rather than time; as a result, the present is at the left instead of the right and he’s confused. He would not be the first climate change skeptic I’ve debated who has done it. ---
**Author:** ![XT](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/xt/32/456_2.png) [@XT](https://boards.straightdope.com/u/XT)\ **Post date:** [December 18, 2007, 8:12pm UTC](https://boards.straightdope.com/t/brazil84s-global-warming-thread/429693/126 "2007-12-18T20:12:24Z")
As something interesting I read today I thought I’d toss in [this](http://news.yahoo.com/s/afp/20071216/sc_afp/usclimatewarmingdenial;_ylt=AqL0v2xGZHf4EmqikbQwicQPLBIF) article: > [@](#): > > Small group of US experts insist global warming not man-made > > WASHINGTON (AFP) - A small group of US experts stubbornly insist that, contrary to what the vast majority of their colleagues believe, humans may not be responsible for the warming of the planet Earth. > ADVERTISEMENT > > These experts believe that global warming is a natural phenomenon, and they point to reams of data they say supports their assertions. > > These conclusions are in sharp contradiction to those of the United Nations Intergovernmental Panel on Climate Change (IPCC), which reached its conclusions using largely similar data. > > The UN body of about 3,000 experts, including several renown US scientists, jointly won the award with former US vice president Al Gore for their work to raise awareness about the disastrous consequences of global warming. > > In mid-November the IPCC adopted a landmark report stating that the evidence of a human role in the warming of the planet was now “unequivocal.” > > Retreating glaciers and loss of snow in Alpine regions, thinning Arctic summer sea ice and thawing permafrost shows that climate change is already on the march, the report said. > > Carbon pollution, emitted especially by the burning of oil, gas and coal, traps heat from the Sun, thus warming the Earth’s surface and inflicting changes to weather systems. > > A group of US scientists however disagree, and have written an article on their views that is published in The International Journal of Climatology, a publication of Britain’s Royal Meteorological Society. > > “The observed pattern of warming, comparing surface and atmospheric temperature trends, doesn’t show the characteristic fingerprint associated with greenhouse warming,” wrote lead author David Douglas, a climate expert from the University of Rochester, in New York state. > [@](#): > > The journal authors “have good reason, therefore, to believe that current climate models greatly overestimate the effects of greenhouse gases.” > > For Fred Singer, a climatologist at the University of Virginia and another co-author, the current warming “trend is simply part of a natural cycle of climate warming and cooling that has been seen in ice cores, deep sea sediments and stalagmites . . . and published in hundreds of papers in peer reviewed journals.” > > How these cyclical climate take place is still unknown, but they “are most likely caused by variations in the solar wind and associated magnetic fields that affect the flux of cosmic rays incident on cloudiness, and thereby control the amount of sunlight reaching the earth’s surface and thus the climate.” > > Singer said at a recent National Press Club meeting in Washington that there is still no definite proof that humans can produce climate change. > > The available data is ambiguous, Singer said: global temperatures, for example, rose between 1900 and 1940, well before humans began to burn the enormous quantities of hydrocarbons they do today. Then they dropped between 1940 and 1975, when the use of oil and coal increased, he said. > > Singer believes that other factors – like variations of solar winds and terrestrial magnetic field that impact cloud formations and the amount of sunlight reaching the Earth’s surface, and thus determining the temperature – are much more influential than human-generated greenhouse gas emissions. Whether these guys are the last, desperate remnants of the anti-AGW skeptics or a new wave of scientists fighting against the main stream view of GW I don’t have any idea. Just thought I’d toss in the article here as this is the only GW type thread currently on the front page in GD. -XT ---
**Author:** ![GIGObuster](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/gigobuster/32/421_2.png) [@GIGObuster](https://boards.straightdope.com/u/GIGObuster)\ **Post date:** [December 18, 2007, 8:56pm UTC](https://boards.straightdope.com/t/brazil84s-global-warming-thread/429693/127 "2007-12-18T20:56:54Z")
[QUOTE=xtisme] As something interesting I read today I thought I’d toss in [this](http://news.yahoo.com/s/afp/20071216/sc_afp/usclimatewarmingdenial;_ylt=AqL0v2xGZHf4EmqikbQwicQPLBIF) article: Whether these guys are the last, desperate remnants of the anti-AGW skeptics or a new wave of scientists fighting against the main stream view of GW I don’t have any idea. Just thought I’d toss in the article here as this is the only GW type thread currently on the front page in GD. -XT [/QUOTE] Alrady referred to in post 57 and replied to in post 58 > **[RealClimate: Tropical tropospheric trends](https://www.realclimate.org/index.php/archives/2007/12/tropical-troposphere-trends/)** > > RealClimate: Once more unto the breach, dear friends, once more! Some old-timers will remember a series of 'bombshell' papers back in 2004 which were going to "knock the stuffing out" of the consensus position on climate change science (see here for... ---
**Author:** ![XT](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/xt/32/456_2.png) [@XT](https://boards.straightdope.com/u/XT)\ **Post date:** [December 18, 2007, 9:03pm UTC](https://boards.straightdope.com/t/brazil84s-global-warming-thread/429693/128 "2007-12-18T21:03:09Z")
Sorry, must have missed that. Carry on. -XT ---
**Author:** ![aptronym](https://avatars.discourse-cdn.com/v4/letter/a/e47774/32.png) [@aptronym](https://boards.straightdope.com/u/aptronym)\ **Post date:** [December 18, 2007, 9:10pm UTC](https://boards.straightdope.com/t/brazil84s-global-warming-thread/429693/129 "2007-12-18T21:10:23Z")
[QUOTE=brazil84] Thank you for admitting that. [/quote] You didn’t read carefully. I am not admitting anything. Re-read your question, and then my answer, and then laugh at yourself for screwing up your “simple yes or no” question. > [@brazil84](#): > > I’m simply pointing out the implausibility of your claim. Except that I prove it plausible. > [@brazil84](#): > > And that [dropping temperatures with rising CO[sub]2[/sub]]shows that your simple calculation doesn’t mean much. No, and if you had quoted beyond the initial “Yes”, you’d know exactly why - the reasoning for the temperature drops are obvious to most people who have taken more than five seconds to think about this problem. Take a look at negative forcing factors in the IPCC links I provided (it’s Figure 6-6 in the 3AR and I forget the reference in the 4AR). Now consider how those forcings have changed over time; specifically, how legislation in the 1970’s might have affected them. Five seconds of critical thinking - that’s what it takes to figure out this perceived contradiction. Five seconds of critical thinking - that’s what it takes to destroy your argument. > [@brazil84](#): > > If **jshore** states or implies that you are wrong, is there any reason I should not mention it? Yes. Because he’s addressing a different point than I am. I never said my calculation was precise, only accurate. > [@brazil84](#): > > There’s no need to do a calculation to conclude that CO2 can affect temperature changes. Despite your love for yes or no questions, you seem to have extraordinary difficulty answering them. Yes or no: Do you accept my first order calculation as proof that CO[sub]2[/sub] is competent to affect the temperature changes we see? This is a question that has been asked of you now 3 times. > [@brazil84](#): > > Not at all. If that’s what you think I did, then you totally missed the point. Then you have no point to make. If you’re using the standard definition of sensitivity as climatologists use it: > [@brazil84](#): > > A model that predicts a lot of warming for a certain increase in CO2 levels is sensitive. A model that predicts less warming for the same increase is less sensitive. Then this line is intuitively obvious: > [@brazil84](#): > > The models predict different amounts of CO2 increases AND different responses of the climate to those changes. > [@brazil84](#): > > Why not answer my earlier question: > > And if we knew exactly how climate responds to CO2, we could predict with much smaller error bars what the future climate will be like. Right? I answered this question prior to you asking it. You’re grandstanding on a non-existent platform. > [@aptronym](#): > > The differences that you see between the SRES scenarios, then, represents economic uncertainty; the variation within a SRES scenario the climatological uncertainty. > [@brazil84](#): > > CO2 output and climate response to CO2 are independent. Temperature is dependant. And it’s not an analysis, I’m just re-grouping the analyses you alluded to. You have two independent variables and one dependent; there exists no such graph in the IPCC report (all the SRES data is temperature vs. time and CO[sub]2[/sub] vs. time), so if you are not fabricating this data, you should have a 3-D graph of temperature vs. CO[sub]2[/sub] output and climate response to CO[sub]2[/sub]. Link me to such a graph since you’re convinced it exists. You don’t need to quote it or paste it; just provide the link and I will click on it myself. > [@brazil84](#): > > No, you’ve got it 100% backwards. I would expect the climate change to be different for different CO2 changes. Great, then that’s exactly what the data shows. > [@brazil84](#): > > (Assuming the same sensitivity to CO2.) But you specifically denied that scenarios have the same sensitivity, since in post #7 you claimed to group according to “sensitive” and “non-sensitive”: > [@brazil84](#): > > we could combine and ridivide the scenarios between “sensitive” and “non-sensitive,” i.e. response of the climate to CO2. It seems like you’ve just taken 100 posts to agree with what I posted in post #23. > [@brazil84](#): > > Please try reading what I post a little more carefully before you hit the reply button … And please read my posts before you quote me. If you haven’t noticed, I’ve taken to not only quoting your old posts, but giving an exact post number so that you cannot weasel out of anything you’ve said in the past. > [@brazil84](#): > > Nonsense. Human well being has clearly been improved by increases in wealth and technology. Vaccines; better communication; etc. No, I contend that human well being has clearly been improved by increases in temperature, and that wealth and technology are only correlating, not causative. You are free to cite the IPCC to prove me wrong. > [@brazil84](#): > > Look at my economic growth thread, in particular the cites about drops in death due to extreme weather. Global warming has caused a 99% drop in our GDP over the past century and we’d all be living to 150 and 100x richer if it hadn’t been for global warming. You are free to cite the IPCC to prove me wrong. > [@brazil84](#): > > Remotely possible So in other words, you’re conceding that it is **not** impossible for global warming to outweigh economic growth. Welcome, now to post #1 - let’s see what science actually says about global warming; after that, you can make an _educated_ judgement about how serious the problem is. > [@brazil84](#): > > Lol. Whatever. I’m not going to spend time looking for quotes that may or may not support your position. That’s your job. You claim to have an open mind to the evidence - so why do you classify looking through data to support _my_ position? If the data doesn’t support my position, then read the relevant sections and point out why I’m wrong. If the data does support my position and you have an open mind, then read the relevant sections and learn why you’re wrong. > [@brazil84](#): > > No, and that’s why I prefer quotes. It’s very easy to just wave one’s hands, point to some long document, and claim it supports one’s position. Except I have not pointed to a long document. I have pointed you to an exact subchapter, and pointed you to a single figure which sums up the data. > [@brazil84](#): > > Haha. Just like in my temperature thread when you stated thus: > > I went through the trouble of looking up your graphs and they didn’t support your position. You were wrong and you never even acknowledged it. You just disappeared from the thread. I neither participate regularly in the temperature thread nor the economic hockey stick thread, and I specifically created this thread to avoid all the problems with proxy temperature data. But you have a good point - I’ll find your response on the other thread and respond (I have to sift through the entire thread so don’t expect it right away), and as far as this thread is concerned, I’ll post quotes from the IPCC 4AR (you’ll still need to do your own research if you want the equivalent quotes from the 3AR or CCR). > [@aptronym](#): > > > [@brazil84](#): > > > > I think that’s [that global temperatures have risen] probably true but I think it’s likely that global temperatures haven’t risen as much as some claim. > > On what basis do you contest the instrumental temperature record? … > > > [@IPCC 4AR WG1: Chapter 1](#): > > > > One recurring homogeneity concern is potential urban heat island contamination in global temperature time series. This concern has been addressed in two ways. The first is by adjusting the temperature of urban stations to account for assessed urban heat island effects (e.g., Karl et al., 1988; Hansen et al., 2001). The second is by performing analyses that, like Callendar (1938), indicate that the bias induced by urban heat islands in the global temperature time series is either minor or nonexistent (Jones et al., 1990; Peterson et al., 1999). > [@aptronym](#): > > > [@brazil84](#): > > > > Originally Posted by brazil84 > > I don’t know [if humans caused greenhouse gas increases]. > > Well, scientists do … > > > [@IPCC 4AR WG1: Chapter 2.3](#): > > > > Emissions of CO[sub]2[/sub] from coal, gas and oil combustion and land clearing have 13C/12C isotopic ratios that are less than those in atmospheric CO[sub]2[/sub], and each carries a signature related to its source. Thus, as shown in Prentice et al. (2001), when CO[sub]2[/sub] from fossil fuel combustion enters the atmosphere, the [sup]13[/sup]C/[sup]12[/sup]C isotopic ratio in atmospheric CO[sub]2[/sub] decreases at a predictable rate consistent with emissions of CO[sub]2[/sub] from fossil origin. > [@aptronym](#): > > > [@brazil84](#): > > > > No [I do not accept that greenhouse gases are competent and necessary to explain warming]. > > On what basis? Scientists disagree with you … > > > [@IPCC 4AR WG1: Chapter 2.1](#): > > > > The differences in radiative forcing estimates between the present day and the start of the industrial era for solar irradiance changes and volcanoes are both very small compared to the differences in radiative forcing estimated to have resulted from human activities. As a result, in today’s atmosphere, the radiative forcing from human activities is much more important for current and future climate change than the estimated radiative forcing from changes in natural processes. > > … > > > [@IPCC 4AR WG1: Chapter 9](#): > > > > Figure 9.5 shows that simulations that incorporate anthropogenic forcings, including increasing greenhouse gas concentrations and the effects of aerosols, and that also incorporate natural external forcings provide a consistent explanation of the observed temperature record, whereas simulations that include only natural forcings do not simulate the warming observed over the last three decades. > [@aptronym](#): > > > [@brazil84](#): > > > > No [I do not believe increases in temperature will cause net harm]. > > On what basis? Scientists disagree with you … > > > [@IPCC 4AR WG2: Summary for Policymakers](#): > > > > This Assessment makes it clear that the impacts of future climate change will bemixed across regions. For increases in global mean temperature of less than 1-3°C above 1990 levels, some impacts are projected to produce benefits in some places and some sectors, and produce costs in other places and other sectors. It is, however, projected that some low-latitude and polar regions will experience net costs even for small increases in temperature. It is very likely that all regions will experience either declines in net benefits or increases in net costs for increases in temperature greater than about 2-3°C [9.ES, 9.5, 10.6, T10.9, 15.3, 15.ES]. > [@brazil84](#): > > Like I said, I’m not your research assistant. I don’t need a research assistant. I’ve done my research. Have you done your own research? ---
**Author:** ![jshore](https://avatars.discourse-cdn.com/v4/letter/j/b5e925/32.png) [@jshore](https://boards.straightdope.com/u/jshore)\ **Post date:** [December 18, 2007, 9:16pm UTC](https://boards.straightdope.com/t/brazil84s-global-warming-thread/429693/130 "2007-12-18T21:16:57Z")
[QUOTE=xtisme] Whether these guys are the last, desperate remnants of the anti-AGW skeptics or a new wave of scientists fighting against the main stream view of GW I don’t have any idea. [/QUOTE] I’d vote for “last, desperate remnants”. In fact, three of the four authors are well-known skeptics who have been around for quite some time now. (The fourth is apparently a grad student.) It is also worth noting that in a press release (and news stories such as the one you picked up), the authors have gone considerably further in what they say than what apparently they have actually published (at least judging from the paper’s abstract and from what I can glean from the RealClimate discussion…I don’t have access to the actual article). ---
**Author:** ![aptronym](https://avatars.discourse-cdn.com/v4/letter/a/e47774/32.png) [@aptronym](https://boards.straightdope.com/u/aptronym)\ **Post date:** [December 18, 2007, 9:28pm UTC](https://boards.straightdope.com/t/brazil84s-global-warming-thread/429693/131 "2007-12-18T21:28:59Z")
[QUOTE=xtisme] Whether these guys are the last, desperate remnants of the anti-AGW skeptics or a new wave of scientists fighting against the main stream view of GW I don’t have any idea. Just thought I’d toss in the article here as this is the only GW type thread currently on the front page in GD. [/QUOTE] Let’s be careful to differentiate between two groups of people. (1) Scientists skilled enough in climatology to be qualified peer reviewers. Among these people (people _with_ expertise, who I’ll call “experts” for lack of a better term), the popularity of an argument doesn’t matter. One expert standing against 999 experts cannot be dismissed or ignored. The strength of the data is paramount, with the caveat that _you must be an expert to assess the strength of the data_. (2) For the 99% of us who aren’t experts - and this includes politicians, political groups, mainstream media, and even well-respected scientists in non-climatology fields - the situation is a little different. We are not qualified to review the primary data - did they use the Raman cross-section of CO[sub]2[/sub] to estimate radiative forcing? Should they have? Hell if we know. We aren’t qualified to assess who’s right and who’s wrong, but we still need to make policy and economic choices that affect our lives. At this point, we must rely on some sort of consensus from the experts. Do we have enough experts lining up on one side to get a pretty good picture of what’s going on? Sure we do. Global warming skeptics will trot out maybe a dozen experts who disagree. Let’s give them the benefit of the doubt and multiply that number by 10x - so on one side we have 100 “experts” who disagree with the IPCC report. We’d like to compare that to the number of people who agree with the IPCC report, but that’s really hard to count; instead, let’s just compare it to the number of _authors_ on the IPCC report, and ignore all the non-author experts who agree. There are 700 authors of the IPCC 4AR. No matter how you measure it, there’s a huge majority of experts who accept rather than reject the IPCC reports. For every “expert” who speaks against the IPCC, realize there’s between 7 and 200 “experts” who have spoken out in favor of it. (The 200 figure is based on the number of pro-AGW peer-reviewed articles vs. the number of anti-AGW articles) ---
**Author:** ![XT](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/xt/32/456_2.png) [@XT](https://boards.straightdope.com/u/XT)\ **Post date:** [December 18, 2007, 9:36pm UTC](https://boards.straightdope.com/t/brazil84s-global-warming-thread/429693/132 "2007-12-18T21:36:35Z")
Sure…and don’t get me wrong here, I actually DO think GW is happening…but there have been times in the past where the vast majority of scientists in the main stream ignored a few folks on the fringe. Who later turned out to be right. I was watching a show on TLC or Discovery about asteroid strikes, for instance…and they were saying that at one time the majority of geologists didn’t believe that the earth HAD been hit by large bodies, at least not in recent (geologically) times. Another one I recall was about how the continents move on plates…at one time the majority of scientists in the field didn’t believe that either. Then there is evolution…at one time most scientists didn’t go for that either. I’m not saying that these AGW skeptics are in that category. However, just because there are only a few of them going against the main stream doesn’t necessarily make the main stream right. Jshore says these guys aren’t ‘experts’ so I’ll buy that…being at work I don’t have time to dig into their backgrounds and I trust him on that kind of thing. I just wanted to include the article as something I read as it related to the thread. -XT ---
**Author:** ![aptronym](https://avatars.discourse-cdn.com/v4/letter/a/e47774/32.png) [@aptronym](https://boards.straightdope.com/u/aptronym)\ **Post date:** [December 18, 2007, 10:48pm UTC](https://boards.straightdope.com/t/brazil84s-global-warming-thread/429693/133 "2007-12-18T22:48:47Z")
[QUOTE=xtisme] just because there are only a few of them going against the main stream doesn’t necessarily make the main stream right. [/quote] We will never know who is “right” or “wrong”. We can only assess whose opinion is “founded” versus “unfounded”. > [@xtisme](#): > > Jshore says these guys aren’t ‘experts’ so I’ll buy that…being at work I don’t have time to dig into their backgrounds and I trust him on that kind of thing. Well, just as a caveat - I don’t know whether these guys are experts either, but there _do_ exist out there legitimate experts who oppose global warming theory. Many self-proclaimed experts have neither expertise nor publications to back up their claims, but a few do. Richard Lindzen is one of the most prominent and most outspoken. There’s another guy in Chicago and a handful of others who shouldn’t be dismissed. Instead, I’d listen carefully to what they’re saying. Lindzen, for instance, agrees that the data shows global warming is real and at least partially anthropogenic. He thinks the IPCC overestimated by about 3x the actual anthropogenic warming (which just means that humans are responsible for 20-30% of the warming in the past 50 years instead of 60-90%). He also thinks that future projections have been overestimated (but agrees temperatures will continue to rise). Whether he’s correct or not, his position is still closer to the IPCC report than it is to the skeptics’ position that the Earth is not heating, that humans are not a cause, and that we don’t know whether the Earth will continue to warm. ---
**Author:** ![MrDibble](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mrdibble/32/114_2.png) [@MrDibble](https://boards.straightdope.com/u/MrDibble)\ **Post date:** [December 18, 2007, 11:16pm UTC](https://boards.straightdope.com/t/brazil84s-global-warming-thread/429693/134 "2007-12-18T23:16:43Z")
[QUOTE=xtisme] I was watching a show on TLC or Discovery about asteroid strikes, for instance…and they were saying that at one time the majority of geologists didn’t believe that the earth HAD been hit by large bodies, at least not in recent (geologically) times. [/QUOTE] I’d love a cite for that. If they meant geologists 100 years ago, then it’s understandable given their dating methods. But more recent than that? Not that I can recall (and I was at uni studying geology when the KT impact thing was all the rage.) [QUOTE=xtisme] Another one I recall was about how the continents move on plates…at one time the majority of scientists in the field didn’t believe that either. [/QUOTE] That’s because no-one had come up with a mechanism and evidence i.e there wasn’t anyone on the other side. Pretty soon after the magnetic striping data came in, it was obvious. That’s the key there - the data, and a mechanism. [QUOTE=xtisme] Then there is evolution…at one time most scientists didn’t go for that either. [/QUOTE] I’ve always been given to understand that most _life scientists_ in England came around pretty soon after Darwin published a valid method. And on the Continent, there were people like Haekel too, although I gather France was a hotbed of Lamarkianism (also evolutionary theory, if wrong) ---
**Author:** ![XT](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/xt/32/456_2.png) [@XT](https://boards.straightdope.com/u/XT)\ **Post date:** [December 19, 2007, 12:00am UTC](https://boards.straightdope.com/t/brazil84s-global-warming-thread/429693/135 "2007-12-19T00:00:51Z")
[QUOTE=MrDibble] I’d love a cite for that. If they meant geologists 100 years ago, then it’s understandable given their dating methods. But more recent than that? Not that I can recall (and I was at uni studying geology when the KT impact thing was all the rage.) [/QUOTE] Well, my Google-Fu isn’t strong today…I can’t figure out even how to look this one up. I know they were talking about the guy who was digging in Arizona at Meteor Crater, and that the main stream scientists of the day were insisting that it was volcanic…not a meteor. And that the predominant theory was that large bodies didn’t impact the Earth, at least not in geologically recent times. I THINK this was less than 100 years ago as well…but as I said, my Google-Fu is weak today and I have no idea how to dig this one up. [QUOTE=MrDibble] That’s because no-one had come up with a mechanism and evidence i.e there wasn’t anyone on the other side. Pretty soon after the magnetic striping data came in, it was obvious. That’s the key there - the data, and a mechanism. [/QUOTE] Well, the exact mechanisms for how climate works are also little understood today, though we are gaining knowledge rapidly. My understanding though is that it is a highly complex process with many ‘forcings’, and that even today the experts don’t know exactly how it works. Additionally, I don’t think that once the evidence was in that the theory of plate tectonics was widely accepted right away…it took time to become the main stream. There are a lot of examples where what we THOUGHT we knew turned out to be wrong…which is why science is such a great thing. It’s self correcting in the long run. Perhaps AGW will be the same…or maybe it will be like Evolution, standing the test of time. I couldn’t say to be honest…I’m not even a good amature on this subject. -XT ---
**Author:** ![jshore](https://avatars.discourse-cdn.com/v4/letter/j/b5e925/32.png) [@jshore](https://boards.straightdope.com/u/jshore)\ **Post date:** [December 19, 2007, 12:30am UTC](https://boards.straightdope.com/t/brazil84s-global-warming-thread/429693/136 "2007-12-19T00:30:34Z")
[QUOTE=xtisme] Jshore says these guys aren’t ‘experts’ so I’ll buy that…being at work I don’t have time to dig into their backgrounds and I trust him on that kind of thing. [/QUOTE] Actually, I don’t think I quite commented directly on their expertise. I more commented on their history. As for expertise, the lead author [David Douglass](http://www.pas.rochester.edu/~douglass/) is a physicist who got interested in global warming late in his career, clearly with a strong bias in the skeptical direction. [Fred Singer](http://en.wikipedia.org/wiki/Fred_Singer) is trained as a physicist and electrical engineer and was, in his time, apparently a good scientist…but then got into denying the effect of CFCs on the ozone layer and then denying climate change, founding the Science and Environmental Policy Project (SEPP) to pursue these. And, he hasn’t really published very much in peer-reviewed journals in these areas. [John Christy](http://en.wikipedia.org/wiki/John_Christy) is clearly the most mainstream published climate scientist of the bunch and I think he has a decent publication record. He is most famous for co-authoring with Roy Spencer the first analysis of the post-1979 satellite record measuring temperature trends in the troposphere. Their first analysis showed the lower troposphere to be cooling, which was a puzzle in comparison to the surface temperature measurements and something that the skeptics very definitely latched onto. Over time, various errors and necessary corrections have been found in their analysis…and so the correction of these (along with a longer data series) has led to a more and more positive temperature trend. There have also been (at least) two other groups who have done the analysis of the data from scratch and have found more positive temperature trends (although now the different analyses have converged enough that the trends may be the about same within error bars). At any rate, I think Spencer and Christy are considered to be a decent scientists, but one clearly with a strong point-of-view (and [Spencer’s weird endorsement of intelligent design theory](http://timlambert.org/2005/08/tcs5/) probably hasn’t helped their reputation). However, it is notable that it seemed like all the major errors that have been found in their satellite analysis pushed the temperature trend in the cooling direction relative to the corrected analysis. I doubt it was intentional but I think they may have let their preconceptions influence their science too much. It is interesting to note that, unlike with the whole Michael Mann thing, Spencer and Christy have not generally been vilified nor been the subject of witchhunts by Congressional Committees despite the large role that their erroneous analysis played in the debate. (Mind you, I think this is a good thing that this hasn’t happened…I do not endorse such action. I am just noting the interesting contrast.) ---
**Author:** ![brazil84](https://avatars.discourse-cdn.com/v4/letter/b/8491ac/32.png) [@brazil84](https://boards.straightdope.com/u/brazil84)\ **Post date:** [December 19, 2007, 1:38am UTC](https://boards.straightdope.com/t/brazil84s-global-warming-thread/429693/137 "2007-12-19T01:38:59Z")
[QUOTE=jshore] I don’t understand why you think one direction is “downhill” and the other is “uphill”. [/quote] Intuitively, it seems like it should be a lot easier to push a system in the direction of a positive feedback loop than against it. As an extreme example, it’s often a lot easier to light a library on fire than to put the same fire out. > [@](#): > > And, just to be clear, the feedback loop operates in both directions. But it can’t operate in both directions at a particular temperature and CO2 level. Right? ---
**Author:** ![jshore](https://avatars.discourse-cdn.com/v4/letter/j/b5e925/32.png) [@jshore](https://boards.straightdope.com/u/jshore)\ **Post date:** [December 19, 2007, 2:38am UTC](https://boards.straightdope.com/t/brazil84s-global-warming-thread/429693/138 "2007-12-19T02:38:20Z")
[QUOTE=brazil84] But it can’t operate in both directions at a particular temperature and CO2 level. Right? [/QUOTE] Assuming I understand your question correctly, the answer is that it can. Take, for example, the feedback loop between CO2 and water vapor. If CO2 levels start to rise, then this warms the climate, which causes water vapor in the atmosphere to increase, which causes further warming. Thus the water vapor feedback amplifies the warming effect due to the rise in CO2. Conversely, if CO2 levels start to fall, then this cools the climate, which causes water vapor in the atmosphere to decrease, which causes further cooling. Thus the water vapor feedback amplifies the cooling effect due to the fall in CO2. In both cases, the water vapor feedback causes an amplification of the effect due to the change in CO2 alone. ---
**Author:** ![MrDibble](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mrdibble/32/114_2.png) [@MrDibble](https://boards.straightdope.com/u/MrDibble)\ **Post date:** [December 19, 2007, 8:46am UTC](https://boards.straightdope.com/t/brazil84s-global-warming-thread/429693/139 "2007-12-19T08:46:22Z")
[QUOTE=xtisme] Well, my Google-Fu isn’t strong today…I can’t figure out even how to look this one up. I know they were talking about the guy who was digging in Arizona at Meteor Crater, and that the main stream scientists of the day were insisting that it was volcanic…not a meteor. And that the predominant theory was that large bodies didn’t impact the Earth, at least not in geologically recent times. I THINK this was less than 100 years ago as well…but as I said, my Google-Fu is weak today and I have no idea how to dig this one up. [/QUOTE] Well, I’m not going to keep ionsisting on a cite, but merely going to ask you if you agree with this: Today, we certainly don’t seriously doubt the possibility of impact events. And the reason we don’t doubt is twofold - **increased and innovative data** (sampling the PGE layer at the KT boundary, improved electromicroscopy to find shocked quartz, hi-res and subsurface satellite mapping etc.) and **improved computer modeling** (modeling impacts and seeing how that agrees with observation). Do you see how the same is applicable to paleoclimate studies? [QUOTE=xtisme] Additionally, I don’t think that once the evidence was in that the theory of plate tectonics was widely accepted right away…it took time to become the main stream. [/QUOTE] Actually, acceptance of plate tectonics was so rapid and the new models so intuitive and useful in so many ways that it represents a true scientific [paradigm shift](http://en.wikipedia.org/wiki/Plate_tectonics#Geological_paradigm_shift). Suddenly, for those in the field, everything made so much more sense, from the igneous guys to the metamorphic guys. Within a few short years, the new theory was being applied to everything from ore body genesis models to analysis of sedimentary basins. I was lectured by professors who were grad students at US universities at the time, and they certainly conveyed to us what a sudden change it was in the entire field. The whole world figuratively lay opened up before them. Suddenly, there were answers - not just to age-old questions (why is this seashell on top of Mont Blanc) but questions they only now knew how to ask (why is the Andes subduction zone igneous terrane different from the Japanese?). It became the mainstream practically overnight (a few short years is overnight in science) ---
**Author:** ![brazil84](https://avatars.discourse-cdn.com/v4/letter/b/8491ac/32.png) [@brazil84](https://boards.straightdope.com/u/brazil84)\ **Post date:** [December 19, 2007, 10:26am UTC](https://boards.straightdope.com/t/brazil84s-global-warming-thread/429693/140 "2007-12-19T10:26:42Z")
[QUOTE=aptronym] You didn’t read carefully. I am not admitting anything. Re-read your question, and then my answer, and then laugh at yourself for screwing up your “simple yes or no” question. [/quote] That’s nonsense. Your actual calculation contained no variable for CO2. It’s as simple as that. > [@](#): > > might have affected them. As I say, it takes most of the meaning out of your “simple calculation.” Five seconds of critical thinking, and it’s obvious your argument is wrong. > [@](#): > > Yes or no: Do you accept my first order calculation as proof that CO[sub]2[/sub] is competent to affect the temperature changes we see? Given that the calculation didn’t even contain a variable for CO2 (see post #10) I would have to say “no.” Post #1 mentions CO2 but doesn’t contain any calculation based on the same. > [@](#): > > I answered this question prior to you asking it. You’re grandstanding on a non-existent platform. I must have missed your answer – could you repeat it? Or quote yourself? > [@](#): > > You have two independent variables and one dependent; there exists no such graph in the IPCC report So what? I never said there was such a graph. Let me ask you this: what are the independent variables in your analysis? What are the dependent variables? > [@](#): > > But you specifically denied that scenarios have the same sensitivity, since in post #7 you claimed to group according to “sensitive” and “non-sensitive”: 😕 I don’t understand your point. > [@](#): > > If you haven’t noticed, I’ve taken to not only quoting your old posts, but giving an exact post number so that you cannot weasel out of anything you’ve said in the past. That’s fine, but sometimes my quote doesn’t say what you claim it does. For example, you claim that I “inisted” on first-order calculations (whatever that means), which I did not do. I simply asked you for a cite for your claim. > [@](#): > > No, I contend that human well being has clearly been improved by increases in temperature, and that wealth and technology are only correlating, not causative. And vaccines are related to increases in temperature how? And radio is related to increases in temperature how? And radar is related to increases in temperature how? > [@](#): > > You are free to cite the IPCC to prove me wrong. Lol. That’s your bible hey? If it’s not in there it don’t matter. Lol. > [@](#): > > So in other words, you’re conceding that it is **not** impossible for global warming to outweigh economic growth. It’s also possible that you’re actualy Liz Taylor. But I wouldn’t bet my life savings on it. > [@](#): > > You claim to have an open mind to the evidence - so why do you classify looking through data to support _my_ position? Classify it as what? > [@](#): > > If the data doesn’t support my position, then read the relevant sections and point out why I’m wrong. Sorry, but I’m not your research assistant. Besides, I already did that in another thread – with predictable results. Anyway, I’m still waiting for an answer to my question. So simple. 0.2C over what time period? Oh, and since you actually quoted your sources, I will take a look at them and consider them. [Previous page](https://boards.straightdope.com/t/brazil84s-global-warming-thread/429693.md?page=6) [Next page](https://boards.straightdope.com/t/brazil84s-global-warming-thread/429693.md?page=8)