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The Skeptical Chymist at 15:53 PM on 21 August 20101934: the 47th hottest year on record
As far as I can tell 2007 is the hottest year in the NCDC global land record. Given that ocean covers most of the worlds' surface using the land-ocean record would be better, which would give 2005 as the hottest year (as noted by other posters). -
johnd at 15:42 PM on 21 August 2010What caused early 20th Century warming?
Marcus at 13:58 PM, SST is a primary influence over the El-Nino, La-Nina cycles. Apart from the heat already in circulation within the oceans, the most obvious means by which SST may vary is solar radiation. However the solar radiation that reaches the surface is dependent on cloud cover and this varies considerably, not only seasonal, but over longer cycles as this diagram indicates, as well as geographic distribution. -
How climate skeptics misunderstand past climate change
johnd - what goes out (storms) must come in (latent heat via evaporation). First law of thermodynamics... -
johnd at 15:14 PM on 21 August 2010How climate skeptics misunderstand past climate change
KR at 14:15 PM, whilst extreme precipitation indicates that a large amount of rain is concentrated on a small area, it doesn't necessarily mean that a large amount of moisture was evaporated from a similarly small area. Certainly in tropical storms that is what drives the storm with the moisture being picked up and then dumped rather quickly over a relatively small area. However at other times it all depends on the circulation patterns with small amounts of moisture being picked up traveling over a vast distance until the system happens to collide with another system that creates the conditions that triggers the rain event. This is what often happens when moisture that is picked up in the Indian Ocean under the normal course of events is transported across Australia to the SE corner where it is released. However there are also times when the remnants of tropical storms that also originated in the Indian Ocean to the NW of Australia also cross to the SE corner where it is released. Whether the rain is released over a wide area or dumped over a smaller area is really dependent on what conditions the rain bearing system collides with. -
papertiger at 14:39 PM on 21 August 2010Dust-Up On Mars: Should Martians Be Sceptical of Global Warming?
We have virtually no historical data about the climate of Mars prior to the 1970s, except for drawings (and latterly, photographs) that reveal changes in gross surface features (i.e. features that can be seen from Earth through telescopes). Not true. We have detailed geographic evidence of changes in the climate on Mars. How? I couldn't tell it nearly as well as J Kelly Beatty of SkyandTelescope, so in his words; "NASA's Mars Reconnaissance Orbiter has been circling the Red Planet since March 2006, for some 4 1/2 years.Yet it's the Mars mission that hardly anybody knows about. As of June 18th, MRO'sprimary camera -- the High-Resolution Imaging Science Experiment, or HiRISE -- had made 16,077 observations and returned 13.4 trillion pixels of digital imagery. Picture yourself viewing the Red Planet through an exquisite 20-inch (0.5 -meter) f/24 telescope without Earth's atmosphere to contend with. Naturally, you'd expect a great view. Now imagine goosing your magnification up another 20,000x by moving that scope to a vantage just 190 miles (300 km) above the Red Planet, and then throw in a camera able to capture long ribbons of terrain more than 20,000 pixels wide and as long as will fit on a 16-gigabyte memory card. This is the reality of HiRISE, which boasts the largest scope ever floan to another planet. With it Geologists once content to decipher Martian geology fron a patch-work of vague features a mile or so across are now able to follow the tracks of boulders that have rolled down from a crater's rim, or to count thin sedimentary layers in an ancient lakebed." Ain't it a beautiful thing? I'd love to continue, but Jack Horkheimer, my ambassador to the stars has died today at the age of 72, so I'll be in mourning the rest of the evening. Probably in front of an eyepiece. Keep looking up. See the Sep 2010 issue of Sky and Telescope, the one off -
Daniel Bailey at 14:28 PM on 21 August 2010Dust-Up On Mars: Should Martians Be Sceptical of Global Warming?
Soundoff, that's perhaps due to the fact that people have a better view of Mars' polar caps than they do of ours. :) The Yooper -
dhogaza at 14:28 PM on 21 August 2010The Oregon Petition: How Many Scientists Does It Take To Change A Consensus?
Thanks for the challenge, many of the arguments are redundant or can be falsified in chunks, but I agree it will take some time, but I'm confident we have plenty of time before climate disaster strikes :)
Oh, this should be fun, black-is-white and up-is-down stuff, and of course all scientists studying such things are wrong because theendisfar is an über genius ... Climate disaster *is* striking, firmly enough that Russia's government, long semi-entrenched in the denialist mode, has talked (at least) about an about-face, and it has nothing to do with international politics (internal political pressure, instead). -
dhogaza at 14:24 PM on 21 August 2010The Oregon Petition: How Many Scientists Does It Take To Change A Consensus?
Yes, I think many climate scientists are purposely misrepresenting conjecture as empirical and repeatable evidence quite frequently using subjective terms to provide wiggle room and plugging conjecture into GCM's, passing the predictions off as reliable.
Doug Bostrom's rebuttal is fine, but it's worth noting that this is *exactly* the argument creationists, smoking-is-harmless types, etc use against science. Look, we should I care what the uneducated think, theendisfar? The more you make clear your ignorance, the less I care ... -
adelady at 14:24 PM on 21 August 2010What caused early 20th Century warming?
johnd Late 1990s rainfall might have been better than the early 90s. But where did it fall? Scroll down this page to the Murray Darling basin and you'll see that rainfall has dived from 2000 onwards. The previous variability seems to have disappeared. One variable has changed significantly. Between 1960 and 1980 only one year has had over 200mm above average, but since 1980 there are 3 years 200 below average and 2 of those are in the last 10 years. It's not a good look. http://www.abs.gov.au/AUSSTATS/abs@.nsf/Lookup/4613.0Chapter55Jan+2010 -
dhogaza at 14:22 PM on 21 August 2010The Oregon Petition: How Many Scientists Does It Take To Change A Consensus?
1. The comments policy forbids it, and the terms I've used are already fairly close to crossing that line. Say what you like but AGW Believers get away with far more here than Skeptics.
We also got better grades in science classes when in school, something I'm sure many denialists still resent ...I agree, skeptics have done just as much a terrible job in rebutting AGW as AGW Believers have done in preparing and proving it. Time for someone else to do the job.
Physics actually works for me. CO2 lasers and all that. You're arguing from a position of personal incredulity ... "I don't believe science, therefore it must be wrong!". You're no different than those who believe the earth is 6,000 years old. -
Doug Bostrom at 14:17 PM on 21 August 2010The Oregon Petition: How Many Scientists Does It Take To Change A Consensus?
The "skeptic" debate wildcard: Yes, I think many climate scientists are purposely misrepresenting conjecture as empirical and repeatable evidence quite frequently using subjective terms to provide wiggle room and plugging conjecture into GCM's, passing the predictions off as reliable. No point in discussing anything with this fellow, he'll just answer anything and everything with conjecture not related to science when pressed. Facts? Nope, just conjecture, speculation. Thanks for saving my time, "theendisfar." You're a skeptic of the new school, not the old school and thus beyond reason. -
How climate skeptics misunderstand past climate change
Eric - extreme precipitation requires extreme evaporation to provide the WV needed. It ain't gonna rain without sufficient water in the air. So an increase in extreme storms indicates an increase in evaporative generation of water vapor, not a total decrease in relative humidity. That doesn't mean that there might not be changes in RH with temperature - just that you cannot assume drier conditions based on more extreme storms, quite the contrary. -
barry1487 at 14:12 PM on 21 August 20101934: the 47th hottest year on record
"Globally, the ten hottest years on record have all occurred since 1998, with 2007 as the hottest." It's 2005, not 2007, according to GISS and NCDC. HadCRU, and the two major satellite records have it at 1998. Making these distinctions is not fit for a 'Basic Version' post, I guess, but you should at least change 2007 to 2005.Response: Hottest year has been corrected from 2007 to 2005. Thanks for the feedback. -
SoundOff at 14:12 PM on 21 August 2010Dust-Up On Mars: Should Martians Be Sceptical of Global Warming?
It is ironic people rush to claim that a polar cap melting on Mars is a sure sign of global warming there, while they are not persuaded by the same here on Earth. -
Doug Bostrom at 14:11 PM on 21 August 2010What caused early 20th Century warming?
Here's another thing to consider, Miekol. Play with the numbers as you please but as a benchmark thought remember, we could for instance this moment increase the incomes of the poorest 40% of the people in the world by roughly an order of magnitude simply by a contribution from the top 20% of earners essentially unnoticeable for many of us, the price of a few deluxe pizzas per year. Let's not make the mistake of believing if we ignore global warming we're going to raise the world's poor into a new level of prosperity. We choose not to do so today, why would we tomorrow? Is something about human nature going to change? How? -
The Oregon Petition: How Many Scientists Does It Take To Change A Consensus?
theendisfar - Nope,, this just isn't recreational. This is about our futures, our descendents futures. It's about how well we've taken care of the world we live in. This isn't a joke, this isn't a rhetorical exercise. This is about living well, doing well, or suffering the painful consequences of bad decisions. Not about scoring 'points' with debate tricks. You want to play semantic games? Fine. You tried that a couple months ago on the CO2 is not the only driver of climate thread, and I simply won't play that game. If you have actual issues with the data or the conclusions drawn from them, we can talk about it. But rhetorical games are not worth playing, not with the current stakes. -
Marcus at 13:58 PM on 21 August 2010What caused early 20th Century warming?
So John D, what do you think drives the El Ninos & La Ninas? We know that Solar Activity increased quite rapidly throughout the first half of the 20th century, yet solar activity has largely been in decline for the better part of 30 years. So if the sun was the primary driver of the events of the first half of the century, what was driving the events of the 2nd half? -
dsleaton at 13:53 PM on 21 August 2010The Oregon Petition: How Many Scientists Does It Take To Change A Consensus?
Theendisfar: yet consensus is what an unskilled public demands in order to perform informed democracy. Because the public is, in general, unable to do the math (due to restraints of time and/or mental faculty), we turn to scientists. We can't trust one scientist. Getting a second opinion is a natural thing to do in such circumstances. We have the opportunity here to get hundreds of second opinions (from the most informed scientists) and see if a consensus exists. Within the scientific community, "consensus" is simply another name for the peer review and publication process: "Here, I tried my best with the math and the lit review, but maybe you'll see something that I missed," which gets answered by a "No, it looks like--to the best of our knowledge--you've done your homework, and the math looks good." Scientists know they're working with an object (the universe) that hasn't yet been fully defined, and no human mind can encompass all the details, so the natural uncertainty that >everyone< must deal with leads to requests (informal or formal) for consensus. Short version: the demand for consensus is for non-experts, and scientists don't do science only for themselves: they do it for us (non-experts and scientists), so it's no surprise when scientists respond to the demand. (oh, except for the Objectivist types, who do all the science from the ground up without relying on any existing research and don't publish because that would be altruistic. They also don't engage in public forums like this either, because that might lead to their pristine individual selves becoming contaminated by the ideas of others, and all of that ungoverned by social contracts.). -
Marcus at 13:50 PM on 21 August 2010What caused early 20th Century warming?
#17. At the risk of straying off topic, not even the most ardent Green is calling for an outlawing of coal or oil as an energy source in the short term-simply that we use what we have much, much more efficiently-especially here in The West. That said, though, most alternatives for coal & oil already exceed them for quantity (the amount of energy that the Earth has in terms of Geothermal, Solar, Tides etc are many times more than what humanity currently use, & will never run out within the span of human civilization). They are also rapidly approaching the point of matching coal & oil for availability, continuity & cost (solar panels, for example, have fallen from $25 per Watt to under $4 per Watt in the space of only 25 years, whilst efficiency has improved from barely 5% to more than 20% in the same time). Some sources of energy (such as bio-gas & co-generation) are already there. Meanwhile, the cost, quantity & availability of coal & oil are actually getting worse-which makes the goal of ridding the world of poverty much less achievable if we continue to rely on them into the future. Of course, much of the world's poverty has less to do with access to resources, & more to do with the continued uneven distribution of said resources! -
theendisfar at 13:28 PM on 21 August 2010The Oregon Petition: How Many Scientists Does It Take To Change A Consensus?
KR, No, I will not flat out state it for two reasons. 1. The comments policy forbids it, and the terms I've used are already fairly close to crossing that line. Say what you like but AGW Believers get away with far more here than Skeptics. 2. To state that someone is lying automatically brings motivation into the debate, and I don't give a damn what their motivations are, about consensus, or someone's credibility. It detracts from the debate. Whether it's incompetence or lying, how about you decide? Folks (in general) try to do the best job they can. Let us do the same. You defend AGW, and I, being the skeptic, will attempt to falsify it. No hard/personal feelings, strictly recreational. I cannot imagine a world where the majority are incompetent and the few dissenting voices are on the ball. History is full of examples. Look, I'm not argue this with you. You stated there are lots of repeatable tests, you provided links, and I'm looking them over now. and those with axes to grind against the consensus have entirely failed to come up with consistent alternative hypotheses other than anthropogenic global warming. I agree, skeptics have done just as much a terrible job in rebutting AGW as AGW Believers have done in preparing and proving it. Time for someone else to do the job. I'll make a prediction. By dismissing consensus, motivations, credibility, and any other subjective influence and by strictly following the Scientific Method, we bloggers will either falsify or confirm the AGW Theory on or before August 21, 2011. Anyone else want to help figure out how to put this debate behind us? I've got several ideas and would welcome additional help. Any objections to starting in the Empirical Evidence post noted in #40? -
miekol at 13:27 PM on 21 August 2010What caused early 20th Century warming?
:-) many thanks Dappledwater, doug_bostrom and scaddenp. You've provided me with heaps of stuff to ponder on. Thank you. I admit I resist the idea that its man's production of CO2 that is causing the current increasing heat retention. My reason is because just when the the human race is on the threshold of ridding the world of finacial poverty, we are going to condemn the world to greater and even more widespead poverty if we 'outlaw' coal and oil as an energy source. Google "Globalism world of plenty." The alternative sources simply cannot match coal and oil for availability, quantity, continuity, and cost. Thanks again guys for your help. Michael -
Berényi Péter at 13:19 PM on 21 August 2010The Past and Future of the Greenland Ice Sheet
Sorry, looks like I've mixed up links. This is Stott 2004. The link above is to Conroy 2008, which is about holocene precipitation history of the Eastern Pacific, based on a Galapagos lake sediments. -
Marcus at 13:04 PM on 21 August 2010What were climate scientists predicting in the 1970s?
RSVP, my decision to reduce my CO2 footprint was not ideological. I actually just wanted to save money & reduce my consumption of non-renewable resources. The reduced CO2 footprint is just an added bargain. That I have succeeded in all 3 endeavors actually proves that, once you strip away the ideological arguments of the Fossil Fuel industry & its Cheer-Squad, you see that mitigating our CO2 emissions can be surprisingly easy & painless. However, like a drug addict, our society is addicted to its inefficient, high-consumption life-style even as it steals the hard-earned money from their pocket. Like good drug pushers, the fossil fuel industry is all too happy to keep encouraging this ongoing addiction-no matter what damage it will cause-so long as it puts money in their pockets. You see, unlike you, I have been more than willing to countenance a *NATURAL* cause for recent global warming, but the fact remains that the evidence for a *NATURAL* cause has been sadly lacking from your side of the debate. Instead, your side continues to engage in cheap political stunts & the demonization of the entire scientific community! Its not *hubris* to be concerned about how our alteration of the planet's atmosphere-in a short space of time-will impact on our climate, but it is the height of naivety to keep claiming its natural when you have absolutely *NO EVIDENCE* on which to base such an assertion! -
Berényi Péter at 12:53 PM on 21 August 2010The Past and Future of the Greenland Ice Sheet
#53 Dappledwater at 09:57 AM on 21 August, 2010 here's that paper Thanks. Section 4 Comparison with proxy data of Renssen 2004 is a good review article in itself (lots of references). Otherwise the paper shows the usual bad habit of identifying computational model runs with experiments so prevalent in climate science. In reality what they've done is a Gedankenexperiment at best, although this kind of computer game lacks the conceptual clarity traditionally associated with the term. Anyway, several thousand years ago the Arctic was considerably warmer indeed than it is today. However, it would be a mistake to assume the Holocene Climatic Optimum was restricted to the Arctic.2004 Nature, 431, 56-59 DOI: 10.1038/nature02903 Decline of surface temperature and salinity in the western tropical Pacific Ocean in the Holocene epoch Stott, L., Cannariato, K., Thunell, R., Haug, G. H., Koutavas, A., Lund, S.
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theendisfar at 12:20 PM on 21 August 2010The Oregon Petition: How Many Scientists Does It Take To Change A Consensus?
dhogaza, :) This is so frustrating. Who cares if someone is getting paid, is their work worth a hill of beans or not? My point is that once you introduce consensus, credibility, or motivation, you are straying too far from scientific method. I keep hearing about all this supposed evidence, but once you start looking at it, it turns out to be a bunch of 'almost' evidence that is all to often used by other scientists as if it has been validated. Once you start nesting 'almost' you end up with almost almost which is worthless to science. It's great for PR work and building consensus. I'm just one guy, give me a few weeks to work on the items in #40. As I stated there, I'm claiming that I can show that this supposed repeatable evidence is exactly that, supposed. NigelJ, Will discuss in link in #40. -
Marcus at 12:08 PM on 21 August 2010What were climate scientists predicting in the 1970s?
@GC. Yes I am aware where our Oxygen came from. I'm also aware (but you, apparently, are not) aware that this process took HUNDREDS OF MILLIONS OF YEARS TO OCCUR. Similarly, Earth's atmosphere used to contain 10 times as much CO2 as it does today, but that also took HUNDREDS OF MILLIONS OF YEARS TO OCCUR. It also took HUNDREDS OF MILLIONS OF YEARS for prehistoric plant life to remove this CO2 from the atmosphere-to give us our current climate system. By contrast, though, humans have fundamentally altered the chemistry of our atmosphere (not just CO2, but methane, nitrogen dioxide & sulfur dioxide) in the space of less than THREE CENTURIES. Yet you & your mate RSVP still run around claiming that concern about such rapid change amounts to "hubris"?! Give us a break! -
The Oregon Petition: How Many Scientists Does It Take To Change A Consensus?
theendisfar - So, you won't flat out state that climate scientists are lying; they may just be incompetent? I don't think that's a reasonable statement at all. Folks (in general) try to do the best job they can. I cannot imagine a world where the majority are incompetent and the few dissenting voices are on the ball. Climate science has been an active and evolving discipline for well over a century - and those with axes to grind against the consensus have entirely failed to come up with consistent alternative hypotheses other than anthropogenic global warming. If the dissenters had solid alternatives, they would be convincing the majority. Facts are unforgiving, and every honest scientist I know follows the facts. -
dhogaza at 11:09 AM on 21 August 2010The Oregon Petition: How Many Scientists Does It Take To Change A Consensus?
Should there be any motivation in science other than being able to repeatedly be able to arrive at the same result no matter who pays you?
Unpaid volunteers are doing their own temperature reconstructions, including an effort by Ron Broberg to put together a usable dataset from the GSOD network, which are stations entirely separate from the GHCN network used to generate GISS, HadCRUT, etc temperature products. Guess what? He gets almost identical results to the GHCN-derived data. Nick Barnes and friends, likewise unpaid volunteers, have recreated GISTemp in Python and have found that GISTemp indeed implements the algorithms defined in the scientific papers, and gets identical output to GISTemp. Anthony Watts's classification of GHCN stations based on his photo project has led to work which shows that even choosing just the best stations by his criteria gives the same temperature rise we see in GISTemp. The first effort to do this was done by a volunteer who goes by the handle JohnV. When Watts denounced his work, JohnV lost all faith in the so-called skeptical community. There are more examples. The fact of the matter is that people who are unpaid are starting to recreate important bits of work. Most telling of all, those who are paid and who would be expected to build a robust argument against the mainstream have failed miserably for three decades now. They've been unable to come up with a theory that accounts for not only observed current warming but past climatic events, the climate of Venus or Mars, etc. Climate science gives us a coherent theory that explains much more than the relatively trivial (in terms of importance to overall science) consequence that adding CO2 to the atmosphere is going to cause warming. If it weren't for the political importance and potential implications for our future, this factoid wouldn't be much more than a footnote in climate science. -
Eric (skeptic) at 10:58 AM on 21 August 2010How climate skeptics misunderstand past climate change
CB, Clausius-Clapeyron describes an ideal local effect and can't be used to determine a water vapor number in real-world circumstances (advection, limited water supply, etc). But in looking that up I see where you and KR are coming from, as described here http://www.dgf.uchile.cl/~ronda/GF3004/helandsod00.pdf (Held and Soden 2000), including Moller's fixed RH assumption. I was trying to show above that a C-C relation can't be applied in nonideal circumstances (i.e. anyplace but flat water with no wind, and certainly not in what I described above). Is your argument then that C-C is applicable globally because C-C will apply to the average situation? Perhaps, but that average situation will be quite complex to describe, perhaps it could be a weighted average of several or many typical circumstances. The best answer I have is already above which is that weather will change as the global average temperature rises. On some threads here it is claimed that it already has changed to an increase in extremes. The extremes in precipitation obviously remove water vapor from the air (that should be obvious?) but the amount will depend on how much those extremes have increased on average. The extremes in temperature which may not be CO2 correspond with extremely low RH. Again if those increase globally, then RH decreases by that amount globally. -
Doug Bostrom at 10:31 AM on 21 August 2010Can't We At Least Agree That There Is No Consensus?
What I'd like to know is how many of Poptech's articles have purely to do w/economic or political matters. They've nothing to do w/physical science and thus are really not very informative about the physical matter of AGW. Anybody care to show a theoretical consensus among political scientists or economists having any seriously quantified impact on the real world? -
scaddenp at 10:17 AM on 21 August 2010What caused early 20th Century warming?
Miekol, as has been asked before, this belongs in "CO2 is an insignificant gas". Please read and ask questions there. A truly excellent resource for all the gory detail is at science of doom. To help concentrate your thinking, consider the following. 1/ How long would you survive if you replaced each CO2 molecule with one of HCN (cyanide). 2/ Each CO2 molecule absorbs a photon, gains kinetic energy and usually loses that energy by collision with other molecules and then ready to absorb another molecule. How quickly does this happen on average? 3/ What would the temperature of the earth be if you removed all the CO2? And yes, the experiment to measure the greenhouse effect of tiny concentrations was done long ago and repeated many times. Look up Arrhenius ( or Spenser Wearts excellent history of the experimental work.) -
Doug Bostrom at 10:17 AM on 21 August 2010What caused early 20th Century warming?
Miekol, see Spencer Weart. And remember, simple doubt is not an argument. You're obviously familiar with how to obtain information, you're here after all. Educate yourself, don't ask other people to stuff facts into your head, against your resistance. -
Rob Painting at 10:17 AM on 21 August 2010What caused early 20th Century warming?
Miekol, time for you to keep your word, some empirical evidence -
Rob Painting at 10:11 AM on 21 August 2010What were climate scientists predicting in the 1970s?
GC @ 23 - humans have added an extra 37% of CO2 to the atmosphere alone since the start of the Industrial Revolution, see here. And if stromatolites can so fundamentally alter the Earth's atmosphere, in oxygenating it, doesn't that suggest that human civilization could likewise have a marked effect?. -
Rob Painting at 09:57 AM on 21 August 2010The Past and Future of the Greenland Ice Sheet
KR, here's that paper Simulating the Holocene climate evolution at northern high latitudes using a coupled atmosphere-sea ice-ocean-vegetation model And an older paper dealing with orbital effects Variations in the Earth's Orbit:Pacemaker of the Ice Ages And yes, the Greenland ice sheet is very sensitive to temperature, hence the rapid melt currently occurring at it's margins. -
Doug Bostrom at 09:54 AM on 21 August 2010What were climate scientists predicting in the 1970s?
GC, I'd suggest that you might in turn work on a "big picture" perspective fully articulating how we do not have the capability to alter to the climate. I'll assert that doing so will be problematic because a big picture is made of many little parts. There are a tremendous number of details indicating we may and indeed are changing the climate, few puzzle pieces available to construct an alternative, coherent image. There I go again, with the metaphors. Can't help myself... -
gallopingcamel at 09:47 AM on 21 August 2010What were climate scientists predicting in the 1970s?
The meme in 1970 that the press picked up on was a new "Ice Age". Since 1988 the meme (thank you Michael Mann & the IPCC) has been "Catastrophic Anthropogenic Global Warming". The underlying argument for CAGW is the increase in the concentration of carbon dioxide in the atmosphere. The pre-industrial concentration appears to have been ~280 parts per million (ppm) compared to the modern 387 ppm. Thus we may have added ~100 ppm of CO2 to the Earth's atmosphere, or 0.1% by volume. Living organisms created so much oxygen that the iron salts in the oceans were converted to insoluble iron oxides that now appear as ore beds. Eventually, the dissolved iron salts were depleted so free oxygen began to build up in the atmosphere, leading to the modern concentration of >20%. Compare the achievement of ancient life forms to the puny achievements of humans who added ~0.1% to the atmosphere. Personally, I support John Cook and the rest of you who want to reduce CO2 emissions but you need to develop a "big picture" perspective that does not exaggerate human capabilities. -
miekol at 09:20 AM on 21 August 2010What caused early 20th Century warming?
#9 Phil, #10 scaddenp, #11 Anne-Marie Blackburn. Phil......Sorry I'm just an average guy. I'm pretty sure that it has been shown empirically that the speed of light is 299,792,458 metres per second and that the mass–energy equivalence formulae is a fact. I agree its not been proven that there's not something that moves faster than light. But I'm pretty sure that E=MC squared is a correct formulae for mass–energy equivalence. Perhaps someone can give me a link if I'm wrong. scaddenp...........Show me a few experiments whereby adding one CO2 molecule to 850,000 molecules of air increases the greenhouse effect. (don't ridicule my clumsy wording. You know what I mean. I'm willing to be corrected on the proportions.I'm not a scientist.) Anne-Marie I've no arguement with the idea that as you say, "The evidence strongly suggests that current warming is mainly the result of increasing greenhouse gas levels." What frustrates me is that GWers assumed that the one extra molecule of CO2 produced by man in 850,000 is responsible for increasing temperatures. As a lay person, I just cannot accept this. You show me a few emperical experiments that demonstrates it, then I'll support human carbon reduction. -
johnd at 08:51 AM on 21 August 2010What caused early 20th Century warming?
During the first half of the 20th century, 10 years were declared as La-Nina years and 13 as El-Nino years. In the second half 12 years were declared La-Nina and 15 as El-Nino. The first half of the century had the longer term IPO predominately in the positive phase which reflects El-Nino conditions whilst during the second half it was predominately in the negative phase which reflects La-Nina conditions. During the first half, on 3 occasions succeeding years were declared El-Nino years whilst La-Nina was declared once for 3 years in succession and once for 2 years also. During the second half, only on one occasion was there succeeding El-Nino years which remained in place for 4 years. On 2 occasions succeeding years were declared La-Nina years, and on one occasion 3 successive years. Interestingly the much discussed 1998 El-Nino event was immediately preceded and immediately succeeded by La-Nina years. Looking at the IOD, during the first half, 8 years were in the negative (wetter) phase and 9 years were in the positive (drier) phase. During the second half there were 8 years each of the IOD being in each phase. All those longer term indications are reflected in the rainfall over all of Australia being generally greater in the second half of the 1900's, with the earlier mentioned 3 successive La-Nina years in the mid 1970's being considered as the wettest period ever since settlement began in the 1700's. Irrespective of what may be considered to being the greater driving influence, it is whether or not the longer term patterns are changing, and if so in which direction that is relevant to what is really the single most important factor, that being mans ability to feed themselves. -
JMurphy at 08:47 AM on 21 August 2010Climate's changed before
cruzn246 wrote : "Here is the page for the solar activities" As well as looking at the picture, how about reading the relevant WIKIPEDIA page for context : The scientific consensus is that solar variations do not play a major role in determining present-day observed climate change. Also, the increase of temperature is a little more than you suggest : The updated 100-year linear trend (1906 to 2005) of 0.74°C [0.56°C to 0.92°C] is therefore larger than the corresponding trend for 1901 to 2000 given in the TAR of 0.6°C [0.4°C to 0.8°C]. The linear warming trend over the last 50 years (0.13°C [0.10°C to 0.16°C] per decade) is nearly twice that for the last 100 years. The total temperature increase from 1850–1899 to 2001–2005 is 0.76°C [0.57°C to 0.95°C]. Summary for Policymakers Finally, this picture (also from WIKIPEDIA) seems to disagree with your assertion about temperatures since we "snapped out of our last ice age" :Holocene Temperature Variations
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TOP at 08:32 AM on 21 August 2010The Strange Case of Albert Gore, Inconvenient Truths and a Man in a Powdered Wig
Dave Horton Actually the denier movement is more religious. This is because of certain presuppositions that differ on either side of the argument. Phil Political agendas translate into laws and court decisions. In the early 60's psychiatric opinion was that the bible and prayer in schools was harmful to some student's psyches. The Supreme Court used that "science" to overturn 150 years of precedent and history. The Scopes trial got evolution pretty close to being the codified into law in many places. At least you can't teach or even discuss opposing viewpoints. Interestingly in this example the science has changed so much from what Darwin wrote that he would be laughed out of any current discussion on the topic. Generally in these kinds of arguments if you don't get down to the presuppositions and how either side is attempting to change them you can't really see what is at stake. -
nigelj at 08:30 AM on 21 August 2010The Oregon Petition: How Many Scientists Does It Take To Change A Consensus?
Theendisfar What basic thermodynamic problems? Exactly and precisely? What data has been missrepresented? What conjecture has been presented as evidence? One example will do. Im intrigued. -
CBDunkerson at 08:23 AM on 21 August 2010How climate skeptics misunderstand past climate change
Eric, no. None of that makes ANY sense. Dry ice: Presumably here you are talking about cloud seeding... though you didn't mention any clouds to be seeded (water vapor is not synonymous with clouds). If you drop dry ice into clouds the chances of precipitation increase. That precipitation would then cause a temporary local cooling effect. No 'extra forcing' is then required to raise the temperature again... water vapor will naturally return to the atmosphere in very short order provided there is a water source nearby (such as the recently fallen rain or the surrounding air for instance). So no... the air does not remain dry after rainfall. All of which is completely irrelevant because you are talking about a short term localized process rather than long term global averages. So one city gets rained on and cools slightly during part of one day.... this is MEANINGLESS on a global scale. Look at it this way. New York City and Miami are both right on the Atlantic ocean. So why is the absolute humidity of Miami on average alot higher than that of New York? Because Miami is closer to the equator and thus on average warmer... which allows more water vapor into the air on more days. If the entire planet gets warmer then that same effect takes place worldwide. How is this not obvious? The connection between temperature increase and atmospheric water vapor which you wrongly state does not exist is known as the Clausius-Clapeyron relation... which has been around since the 1830s. -
theendisfar at 07:46 AM on 21 August 20102nd law of thermodynamics contradicts greenhouse theory
To whom it may concern, Well put, thank you :) -
theendisfar at 07:41 AM on 21 August 2010The Oregon Petition: How Many Scientists Does It Take To Change A Consensus?
KR, I wasn't accusing you of anything Sorry, I wasn't clear. I claim to be able to refute AGW as to having repeatable tests, was just asking that you provide links to it (you did, thanks:) rather than rely on credibility. All to often, we skeptics get 'credibility' tests that are truly moot IMHO, I claim no credibility save what may rise from this exercise. I did, however, ask if you thought the majority of climate scientists are lying, yes or no - you didn't answer that question. :) Calling someone a liar could be considered ad hominem, so you got a carefully crafted answer :) Sorry about that. Without going into motivation, Yes, I think many climate scientists are purposely misrepresenting conjecture as empirical and repeatable evidence quite frequently using subjective terms to provide wiggle room and plugging conjecture into GCM's, passing the predictions off as reliable. Most climate scientists, IMHO, cannot see the forest for the trees and truly misunderstand thermodynamics, or at least are not properly representing/considering Convection and Evaporation in their studies/calculations, especially models. Whether these folks are lying or not makes little difference as to whether they are providing valuable arguments/tests that result in validating conclusions. I believe I can show that they are not. Empirical evidence that we're causing global warming is right on topic, so I'll begin there if you have no objections. The video you linked is on topic for the above link so I think it should be okay to discuss there. Thanks for the challenge, many of the arguments are redundant or can be falsified in chunks, but I agree it will take some time, but I'm confident we have plenty of time before climate disaster strikes :) Pick this up this weekend in the other thread, it's 5:30 here and time for a beer.Moderator Response: Thank you for recognizing the relevance of other threads, and for promising to read them and watch their video before commenting more. Also thank you for your civil tone even when making strong claims. (I want commenters to know that it is indeed possible to do those things, and that everyone appreciates effort to follow the rules.) -
Eric (skeptic) at 07:38 AM on 21 August 2010How climate skeptics misunderstand past climate change
CB, for the first question let me give a simpler example. Take an area with high temperature and humidity (e.g. 80 and 75%) and drop tiny grains of dry ice uniformly over it. The moisture will precipitate out and the temperature will drop. Apply forcing to warm the area back to 85. At that point it will be warm and dry perhaps 30-40% RH. Or warm to 85 without precipitating and the RH will be approx 65%. The only difference in the two scenarios is weather, but one has much lower RH and the rest of the water is in the river (where it flows away without evaporating). There is no physical law of any sort that favors one scenario over the other, or any law that requires balancing scenarios (more evaporation to balance more condensation). Weather simply doesn't balance. So as the world warms, there is no reason that the RH would stay constant unless the weather stayed precisely the same on a globally averaged basis. The problem with the simple math is that there is no physical reality to base it on. There is no global physical mechanism that results in a particular percentage increase in WV for an increase in temperature. It mostly depends on weather as in the above scenarios. Even though there will be more evaporation, it is unevenly distributed and unevenly condensed and precipitated giving an unknowable relationship between the global average temperature and total amount of water in the atmosphere. In the extreme case I merely need to add more dry ice and more forcing to keep the temperature higher with lower RH. -
2nd law of thermodynamics contradicts greenhouse theory
Regarding molecular collisions and heat distributions: At surface temps and pressure each air molecule (CO2, O2, N2, argon, etc.) collides with another molecule roughly one billion times per second (thanks, Ned). The relaxation time for an energized CO2 molecule is 100ns or more, depending on the vibrational state. That means that an IR energized CO2 molecule has on average a minimum of 100 collisions with other molecules before it has a chance to emit IR. CO2 _will_ maintain thermal equilibrium with the rest of the air mass, whether the air mass as a whole is cooling or heating by IR. (Or conduction, convection, latent heat changes, etc.) -
nigelj at 07:32 AM on 21 August 2010The Oregon Petition: How Many Scientists Does It Take To Change A Consensus?
Isnt catsotrophic heating a bit loaded? Or a straw man? It paints a picture of the imminent destruction of every lifeform on earth and nobody is predicting that. If the petition had asked do you agree we are causing climate change that could cause serious problems for many countries would 32,000 have said no? Not likely now is it. And thanks to skepticalscience for a great site. -
The Past and Future of the Greenland Ice Sheet
BP, DappledWater - fair enough, I appear to have been quite incorrect about the temperature distributions. However: What I'm reading on the Holocene temperature distributions is that the Northern Hemisphere was much warmer, while the Southern Hemisphere was considerably colder. What I've found here (Vinther et al 2009) and here (Kelly 2009?) seem to indicate that the Greenland ice sheet receded 10's of kilometers during the Holocene, with associated thinning and mass loss. Sea levels rose considerably over the Holocene, but only to present values - perhaps the remainder remained locked up in the (much colder) Antarctic? The paleo data on Greenland ice recession certainly indicates some sensitivity to temperature. -
The Oregon Petition: How Many Scientists Does It Take To Change A Consensus?
theendisfar - I wasn't accusing you of anything, if you read my post; I was pointing out that many organizations promoting doubt in climate change have financial incentives to, well, make stuff up. As to those in charge of various gov't agencies, well, yes, sometimes they do modify the message for political goals. The last Bush administration was notorious for that - political appointees rewrote major portions of scientific reports to dilute the data regarding climate change. The scientists who wrote it, however, objected quite loudly. A number resigned in a very public fashion. I did, however, ask if you thought the majority of climate scientists are lying, yes or no - you didn't answer that question. As to repeatable methods and conclusions? Global warming is still happening Emperical evidence that we're causing global warming CO2 emissions CO2 effects (evidence disproving 'saturation') Greenhouse effect (lots of references) Greenland/Antarctic ice loss Sea level rise Consensus and paper counts, AGW and counter-AGW Tons of other evidence, with links to the various references I believe that provides a cross section of ~60 papers total, which various folks indicate are representative. If you want to invalidate all of those (the vast majority of climate science, in fact), be my guest. It might take a while, though. I would actually suggest you start with the last link, the video, and look up the web page he provides at the end with all the references he used. It's a good review of the various lines of evidence in the field.
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