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Comments 99251 to 99300:

99251. Albatross at 09:31 AM on 6 January 2011
       Not So Cool Predictions
       Trans @49, Umm, it is "anthropogenic". "We've actually just had the coldest night recorded -27 degree's" This statement is completely meaningless without context. " i dare say cooling is the thing we should worry about, it poses a far greater danger" One, global temperatures are not cooling, 2010 is likely going to be the warmest on record. Two, heat is the number cause of weather-related deaths in the USA, cold ranks lowest on the list. Source here.
99252. lurgee at 09:29 AM on 6 January 2011
       Understanding the CO2 lag in past climate change
       @ Sphaerica I'm more than familiar with the Wikipedia pages on ice cores, and I have taken time to read comments and papers published by the experts you refer to. They bear out what I said - that interpreting ice core data is fraught, even with all their expertise and the years they have spent working with the cores. I am not disrespecting them or their work - I am reflecting what seems to be their considered opinion. Can you point to a paper published by someone with suitable credentials, stating that the various problems I mentioned (Difficulty distinguishing local from global variation, and 'noise' from the inaccuracies inherent in the record. Hence my doubt about the wisdom of relying on a single core, or trying to 'refudiate' AGW on the basis of CO2 lagging temperature on the way down. If you compare different ice cores, you'll see significant variation between them. Vostok, for example, records a significant upwards blip in temperature, abOUT 8,000 years ago. Grip, at the same time, records an equal drop in temperature. EPICA doesn't show much of a trend at all (You see, I do have a Wikipedia+ familiarity with the topic). Is there any way of telling which represents a global change, local variation or just taint? FWIW, I'm no sceptic on climate change. I accept it is happening, it is largely our fault and it is going to have devastating consequences if we don't act. I was suggesting - to an apparent doubter - why some of the claims he made were dubious, based on my own limited understanding. It's a pity you failed to address the points I raised, either supporting them or countering them, preferring to snipe at me, personally. You had a chance to enlighten, but you missed it. As for my amateurism, if you're willing to pay me for my comments, I'll happily upgrade my status from 'rank amateur' to 'professional.'
99253. Bibliovermis at 09:28 AM on 6 January 2011
       Not So Cool Predictions
       Transjasmine, Do you understand the difference between local weather and global average temperature?
99254. transjasmine at 09:18 AM on 6 January 2011
       Not So Cool Predictions
       its funny, this site is called skeptical science yet the only thing you people seem to be 'skeptical' about is anything and everything that disagree's with anthropomorphic global warming. we've actually just had the coldest night recorded -27 degree's, and actually i dare say cooling is the thing we should worry about, it poses a far greater danger.
99255. hfranzen at 08:31 AM on 6 January 2011
       The Physical Chemistry of Carbon Dioxide Absorption
       It's a pleasure - I greatly appreeciate the feedback.
99256. stefaan at 08:29 AM on 6 January 2011
       Did Global Warming stop in 1998, 1995, 2002, 2007, 2010?
       Hi, On the CNN website there is an intersting (and popularized) artcle about the GW and the slight decrease of warming speed the last decade. case for man made warming increased in 2010, scientist say Next to the aerosols and water vapor they mention, it's also a fact that the sunspot cycle went downwards the last 10 years, so even if this is a small influence it might also slow down the heating (until it goes up again of course). solar cycle data
99257. Rob Painting at 08:14 AM on 6 January 2011
       Understanding the CO2 lag in past climate change
       apiratelooksat50 @ 29 - Biodiversity refers to number of species. Biomass refers to the total mass of living biological organisms at any given time and place I don't want to veer this too far off topic, however I would expect a person teaching environmental science, might have a better understanding of the relevance of biodiversity and how it pertains to biomass. The relationship holds true today, consider the incredible biodiversity and associated biomass of the tropical rainforest, compared to the dry forest. And the biodiversity of the coral reefs and the huge biomass compared to less bio-diverse shallow oceanic regions. Biogeochemical cycle studies of the Phanerozoic, support this view too. So what leads you to suppose the time of the dinosaur was any different?. I don't have a clue about the biomass at that time but your chart is not applicable. If you don't have a clue, how can you then claim it's not applicable?.
99258. caerbannog at 08:11 AM on 6 January 2011
       Understanding the CO2 lag in past climate change
       Some questions for "skeptics" to think about (should they decide to do so): When the eccentricity of the Earth's orbit is at or near a maximum, and the precession phase is just right, the SH will receive more solar energy than the NH (or vice-versa). When this happens, the two hemispheres will be 180 degrees out of phase with respect to the amount of solar energy they receive. Yet in spite of this fact, for the past several hundred-thousand years, the two hemispheres have warmed and cooled together on Milankovitch-forcing time-scales, even during these times of maximum hemispherical solar-energy imbalance. Why is this the case? Why didn't one hemisphere cool while the other warmed when these hemispherical imbalances of solar energy occurred? What kept the hemispheres "locked in phase" (on Milankovitch time-scales) with respect to warming/cooling during these times? Now go back a little over 35 million years. At that time, the Sun was slightly dimmer than it is now, and the latitudinal distribution of the Earth's continents was almost exactly the same as it is now. So the total solar + land-albedo forcing was about the same (or ever so slightly weaker) than it is now. Yet the Earth's poles were nearly or completely ice-free, and the Earth was too warm to cycle between glacial and interglacial phases. Why?
99259. Bob Lacatena at 08:08 AM on 6 January 2011
       What's in a Name?
       5, reluctant skeptic, Regardless of history or intent, I do think that "climate change" is more appropriate, particularly to the man-on-the-street who is going to (idiotically) look at the most recent snow storm/cold snap/whatever and say "what global warming?" The point is that global warming doesn't necessarily mean warming everywhere or in the same proportions, and it doesn't mean "no more winter." It also can mean things completely (seemingly) unrelated to temperature, like floods, droughts, and more. Climate change is a lot easier to explain as far as an individual's experience with it, because it implies all of the nasty things that go along with global warming: precipitation changes that result in more or harsher droughts, more/harsher flooding, ecosystem changes, altered growing seasons and plant/crop viability, arctic ice melting, etc., etc. So regardless of who started it, to me "climate change" is a far superior moniker when discussing the ramifications of global warming, both to peoples as a whole, and the individual.
99260. citizenschallenge at 07:52 AM on 6 January 2011
       Why I care about climate change
       I'm one of them old timers, I learned about climate science before graduating high school in 1973. Never been a scientist, but always loved and learned about science, meaning I've been spending four decades keeping up on the science and the public dialogue, from a working layman's perspective. ~ ~ ~ ~ ~ ~ ~ I've been dialoguing over at http://www.skepticforum.com/viewtopic.php?p=223791#p223791 with a bunch of Skeptics. I hope you don't mind me sharing most of a recent post: Re: "Expert Credibility in Climate Change" examined Post #13 {...} Yes Christy is an interesting unique fellow, scientist. He was one of three scientists to land in both CE & UC lists. His science is one thing. His political pronouncements and very public advocacy are another. Do you appreciate that distinction? One problem with trying to communicate with "sceptics" is that they're all over the place. Big people like Senator Inhofe and his Morano make one deceptive, often down right fraudulent, claim after another - yet the troops are lining up behind him and his political machine. John Christy is a lot more nuanced and thoughtful - yet his main political message seems to be against any proactive political recognition or intervention in our self created AGW situation which he acknowledges is real. Instead believing that historic economic rules of the free wheeling free market approach should be encouraged, because more energy and consumption is what society needs to achieve more progress. Incidentally, another disturbing habit of "sceptics" is that rather than engage in a constructive dialogue of discovery with the "consensus science/scientists {and their fans} they resort to ridicule and rejection in the basest of terms. As though they've figured it out and all those other dude's are crazy. What's up with that? As for conclusions, I guess mainly that ~97% of real climate scientists agree upon the CO2 science and the basics of AGW as presented {in addition to wanting to continue the pursue of better understanding of the details}. But, that we know enough about the beast, that society needs to stop dragging its feet and pretending that this climate transition isn't going to have tremendous impacts upon society as we know it. ~ ~ ~ ~ ~ ~ ~ Peter M http://citizenschallenge.blogspot.com
99261. Scrooge at 07:49 AM on 6 January 2011
       Understanding the CO2 lag in past climate change
       To gary thompson.. As discussed previously on this blog and others you may be right that we should be in a cooling trend, but that it is being overwhelmed by AGW. The rate of cooling is so gradual that if you cant believe the data showing the current warming there is no way you can say there is a cooling signature. To say we haven't been warming really requires blatant cherry picking and a vivid imagination. The warming trend continues just as expected. But anyway when we look at the what should be cooling, and is actually warming the statement that AGW accounts for 80 to 120 percent of the current warming seems pretty accurate. Also more in line with this post, previously co2 was a feedback, in the current situation it is the driver. IMHO. I do like when Mr thompson comes here and posts, he is civil, and does make for a lively discussion.
99262. curiouspa at 07:18 AM on 6 January 2011
       What's in a Name?
       just observation- it does seem climate change has replaced global warming in the media. Not sure why and doesn't seem like it makes any difference either way. Just curious- do most folks think this is mainly based on push from fringe skeptics, media, or some other source?
99263. muoncounter at 06:38 AM on 6 January 2011
       Understanding the CO2 lag in past climate change
       #52: Albatross, That's a terrific summary graph of the mess we've put ourselves in. Great find!
99264. Albatross at 05:52 AM on 6 January 2011
       Understanding the CO2 lag in past climate change
       Sphaerica @50, To add to your and Phila's excellent discussions-- this Figure also places the radiative forcing from CO2 in context. The above image was sourced here, where a table is available.
99265. Bob Lacatena at 05:34 AM on 6 January 2011
       Understanding the CO2 lag in past climate change
       43, apriatelooksat50,

       Does anyone have a source for a chart showing the other greenhouse gases and their relationship with the temperature cycle?

       First problem, what is "the temperature cycle?" No such thing. You mean "relationship with global temperatures," period, no "cycle." Beyond this, there are several ways to look at this. The first way to look at it is relative strength as a greenhouse gas, molecule for molecule, and that in itself is an oversimplification. A molecule will absorb (and emit) energy in varying wavelengths, based on its geometry, and that has to be taken into consideration when looking at the absorption/emission profile of the body in question (i.e the Earth). You have to study molecular physics to understand that. There aren't really any simple numbers (this is twice as strong as that). The second way to look at it is their relative prevalence in the atmosphere. The most common by a mile, and from that point of view the "strongest," is H₂O. CO₂ is pretty much next. Methane, CH₄, is molecule for molecule a "strong" greenhouse gas, but there's a lot less of it. The third way to look at it is the way they get there, and how long they stay. If there's no ready source, or if they don't hang around, any effects on global temperatures would be transient. H₂O is the most common, but it's also the most malleable, in that it's prevalence should be pretty directly tied to temperature. As temperatures go up, H₂O goes up, and temperatures go up further. As they go down, H₂O goes down, and temperatures drop further. CH₄ is in short supply partly because its residence time in the atmosphere is short... when it gets there, it doesn't stay there long. So it's not going to be that big of a danger in the long term. The thing about CO₂ is that once it gets into the atmosphere, it takes a long time to "fall out." It mixes well, and the greatest sink -- the ocean -- is temperature dependent. The higher the temperature of the ocean, the less CO₂ it absorbs from the atmosphere (or, to put it another way, the more CO₂ it releases into the atmosphere, depending on the balance at the time).
99266. Bob Lacatena at 05:18 AM on 6 January 2011
       Understanding the CO2 lag in past climate change
       43, apiratelooksat50,

       The sole focus on CO₂ (and anthropogenic CO₂ at that!) troubles me. Does anyone have a valid reason for the focus on CO₂?

       I have a hard time believing that you teach environmental science, even at the high school level. This is pretty basic stuff. That said... there is no "sole focus" on CO₂, and there's no need to qualify "anthropogenic CO₂" as if it's a different animal. As far as "sole focus" goes, no, scientists have studied myriad different climate influences, from changes in insolation to GCRs to land use to greenhouse gases and more. These have been studied through observation and statistical analysis (i.e. "is there a correlation") as well as logic (i.e. "if A causes B, and there is more A, then there should be more B"). All of these studies have arrived at bupkis as far as evidence, either empirical or logical, for marked contribution to the current warming, except for CO₂. In addition, it would be a very surprising result if we were not seeing warming from CO₂. That would require lots and lots of research funding, because it wouldn't make any sense. As far as anthropogenic versus other "types" of CO₂... CO₂ is CO₂. It's merely a question of what is causing CO₂ levels to rise, and that is unquestionably the result of burning huge quantities of fossil fuels (i.e. carbon that has been sequestered under the ground for hundreds of millions of years, with no way until now to get out). So, no "sole" focus, and no "anthropogenic" form of CO₂. In fact, your entire statement reeks of a denier trying to color things in a certain way, rather than that of a person truly looking for education.
99267. dmyerson at 05:16 AM on 6 January 2011
       Understanding the CO2 lag in past climate change
       Since the glacial cycle is a big topic now, it seems to me that the varying temperature slope pre- and post-glacial is an important aspect that doesn't get much attention. It warms up going into an interglacial much faster than it cools when leaving it, in the last few cycles. Since the triggering process of orbital variations presumably has the same forcing gradient on both sides, doesn't this imply that the Milankovitch cycles couldn't possibly be the sole cause of the cycles, and that positive feedback is a requirement. And also that positive feedback is much stronger on warming than on cooling? I point this out and ask about it because it seems that the more scientifically-oriented skeptics these days focus on sensitivity and claim that there is little or no evidence of positive feedback. The above seems to indicate that belief in strong negative feedback from clouds is misplaced and hard to support. Unless the feedback part of the process works completely different now than in the glacial cycles (due to a different trigger). Is there a reason to suggest that?
       Moderator Response: [Daniel Bailey] Google clathrate gun hypothesis.
99268. les at 05:16 AM on 6 January 2011
       What's in a Name?
       In the spirit of graph based nit-picking... If you do the Ngram for UK English and US English you will find that CC is still on the rise in the UK although GW is dying out... so global warming isn't actually global, but climate change is! British English American English I hope this doesn't fuel any "global warming" skepticism!!
99269. pbjamm at 05:10 AM on 6 January 2011
       Understanding the CO2 lag in past climate change
       Glenn Tamblyn @16,17 - Thank you for this. A lot of time is spent arguing the minutia of various bits of Climate Science, having it put back together in a coherent whole helps keep it in perspective. Philia @44 (and Spherica quoted) - A great summary of the contrarian method and mindset. Enough dusty tuxs to open up a rental shop.
99270. dana1981 at 05:07 AM on 6 January 2011
       What's in a Name?
       Exactly Alexandre - it's an attempt to support one myth (global warming stopped) with another myth (they changed the name). Skeptics are building up a mythical house of cards, stacking one myth on top of another!
99271. r.pauli at 05:06 AM on 6 January 2011
       What's in a Name?
       We are in an age of global climate destabilization, anthropogenic heating, and beginning biological extinctions. Climatologists offer one phrase, but oceanographers another. We may have radically understated the situation. This is the end of a too brief Anthropocene. By inventing a descriptive term for it, we help process what is happening. One way to evaluate this change is to measure all the changes against statistical deviations. And then assign a moniker to encompass all the changes outside of norms. This is the Hockey Stick Extinction
99272. les at 04:59 AM on 6 January 2011
       The Physical Chemistry of Carbon Dioxide Absorption
       re #32 Thanks! I hadn't "joined up" the 4th power bit.
99273. Alexandre at 04:58 AM on 6 January 2011
       What's in a Name?
       A friend of mine brought up this argument a short time ago. You have to admit the perverse beauty of this myth. It's a PR masterpiece. Once it's spread, every time the guy hears "climate change" he thinks "aha! I knew it wasn't warming anymore!". Just by mentioning climate change, you make the media work to strengthen doubt, without one single piece of data or evidence. No evidence that warming stopped, no evidence that the name had been "changed". Nothing. Just PR.
99274. Alec Cowan at 04:50 AM on 6 January 2011
       There's no correlation between CO2 and temperature
       @kdfv #3 Please, share data (for instance 54°F) not adverbs + adjectives (no noticeable, virtually doubled). Your ordered pairs like (1946; 'same same') are not very functional. Links and you transcribing the few significant data will suffice. [Don't forget you have also some things to reply in other posts] @Everybody I would be good to stop replying half cooked comments. For instance, it's easy to choose a couple of years and looking in temperature maps find then a lot of places where temperature have not changed substantially, for instance, as I remember, a third of the Bible Belt for the last 50 or 60 years . But we all know how these sort of 'naive' assertions work, so let the 'innocent' at least to do the work of documenting it.
99275. Anne-Marie Blackburn at 04:19 AM on 6 January 2011
       Not So Cool Predictions
       JMurphy The mind boggles.
99276. Phila at 04:18 AM on 6 January 2011
       Understanding the CO2 lag in past climate change
       apiratelooksat50 @43: The sole focus on CO2 (and anthropogenic CO2 at that!) troubles me. Regarding the "sole focus" misconception, please see CO2 is not the only driver of climate. Regarding the "anthropogenic CO2" comment, the simplest explanation is that anthropogenic CO2 is significant because it's rising dramatically, and natural CO2 isn't. For more details, please see Human CO2 is a tiny % of CO2 emissions. Does anyone have a valid reason for the focus on CO2? 1) CO2 is a greenhouse gas; 2) CO2 levels are rising due to human activity; 3) We are observing the warming we'd expect given 1 and 2.
99277. Anne-Marie Blackburn at 04:15 AM on 6 January 2011
       Understanding the CO2 lag in past climate change
       apiratelooksat50 The reason this article focused on CO2 specifically is down to the fact that it directly addresses the argument by contrarians that CO2 cannot be driving current global warming as it didn't drive global warming in the past 400,000 years or so. In general, the focus is not solely on CO2. CO2 remains the main focus as it has the greatest impact on radiative forcing of all other factors. But factors such as black carbon, changes in albedo, solar variability and volcanic activity are also considered in the overall picture. Have a look at chapter 2 of the IPCC's scientific report for more information.
99278. Phila at 04:00 AM on 6 January 2011
       Understanding the CO2 lag in past climate change
       Sphaerica: One of the things that bugs me to no end is the presumption that scientists are stupid, that a layman sort of wandering around a blog in "just thinking things through, using, you know, common sense" is going to come up with all of these ideas that were maybe missed by scientists who studied for decades to earn their degree of knowledge and proficiency, and who now as a profession focus on the topic for eight or more hours a day, five or more days a week. Ditto. As one of my teachers said, "If you're getting results that challenge the scientific consensus, there are two possibilities: You're a genius who's going to win the Nobel Prize, or you made a mistake somewhere." It seems like a lot of "skeptics" would respond to this statement by running out and buying a tuxedo.
99279. kdfv at 03:57 AM on 6 January 2011
       There's no correlation between CO2 and temperature
       Why is it that when I compare the average monthly min/max ratio for 1946 to 2009 for Norfolk Airport Virginia, there is no noticeable change, yet carbon dioxide has virtually doubled? I would expect to see the ratio reducing.
99280. apiratelooksat50 at 03:44 AM on 6 January 2011
       Understanding the CO2 lag in past climate change
       1. Does anyone have a source for a chart showing the other greenhouse gases and their relationship with the temperature cycle? 2. The sole focus on CO2 (and anthropogenic CO2 at that!) troubles me. Does anyone have a valid reason for the focus on CO2?
99281. caerbannog at 03:44 AM on 6 January 2011
       Understanding the CO2 lag in past climate change
       Dr. Richard Alley has a nice rebuttal to those who like to parrot "Cause precedes effect. Get used to it." in any discussion about CO2's role in glacial/interglacial transitions. Go to http://www.agu.org/meetings/fm09/lectures/lecture_videos/A23A.shtml First, watch the segment at 03:45-05:00; then skip ahead and watch the 34:50-38:50 (approx) segment. Case closed.
99282. Phila at 03:38 AM on 6 January 2011
       Understanding the CO2 lag in past climate change
       gallopingcamel: I have a general objection to "Climate Science". Frankly, this statement strongly suggests that you are someone who should not be taken seriously. The way to overcome this impression is not to continue posting witless conspiracy theories and snide generalities about "science," but to read articles like Anne-Marie's more carefully, educate yourself where necessary, and offer logical, evidence-based rebuttals to specific points instead of slandering an entire scientific discipline. In short, don't proceed from the assumption that everyone's wrong and proving it is a simple matter of throwing enough mud at strangers. Instead, please consider the far more likely possibility that it is you, rather than the world's climate scientists, who are failing to make an intelligent, informed assessment of the evidence. Doing so will put you in a better position to make thoughtful counterarguments to specific claims, or to debate the proper course of action. Wallowing in situational ad hominem, as you've been doing here, simply makes you look like a fool.
99283. caerbannog at 03:29 AM on 6 January 2011
       Understanding the CO2 lag in past climate change
       gallopingcamel at 17:09 PM on 5 January, 2011 The tortured logic by Ms. Blackburn and Jeffrey Severinghaus are good examples of the nonsense that surrounds CAGW dogma. Jeff Severinghaus is a full professor at the Scripps Institution of Oceanography. He is one of Scripps' leading scientists. The Scripps Institution of Oceanography, BTW, is that little place that was recently rated as first in quality nationwide for doctoral programs in meteorology, oceanography, and atmospheric science by no less than the National Academy of Science (linky here: http://scrippsnews.ucsd.edu/Releases/?releaseID=1114, doubters are free to track down the original NAS/NRC report with a bit of googling). Someone who dismisses Dr. Severinhaus' work as "tortured logic" and "nonsense that surrounds AGW dogma" truly is taking Dunning-Kruger to the next level.
99284. Bob Lacatena at 03:19 AM on 6 January 2011
       Understanding the CO2 lag in past climate change
       36, garythompson,

       ...maybe it is my ignorance...

       As I said to Lurgee, this isn't acceptable. You can accept what the experts say, or you can study it enough to know the difference. It's unacceptable to simply say "I don't know myself, but I think they might be wrong." One of the things that bugs me to no end is the presumption that scientists are stupid, that a layman sort of wandering around a blog in "just thinking things through, using, you know, common sense" is going to come up with all of these ideas that were maybe missed by scientists who studied for decades to earn their degree of knowledge and proficiency, and who now as a profession focus on the topic for eight or more hours a day, five or more days a week.

       ...if anyone has a good source for that i'd enjoy reading that.

       Now that's the right attitude! Simple place to start is here, at Skeptical Science -- Tree Ring Proxies. If you have the time and the background, you can get a lot more detail from this study. In general, though, the Internet is a vast and intriguing place. A little bit of searching will find a lot of information -- as long as you're smart enough not to take it at face value, and to realize that any old schmuck can publish his opinions as fact on the Internet. Be wary of sneering skeptics, and always check the quality of the source information. If possible, look for independent confirmation (which is not the same as just finding the same lie repeated over and over on the multiple sites with an agenda to push). But it's all there to be had, right at your fingertips.
99285. Alec Cowan at 03:11 AM on 6 January 2011
       Understanding the CO2 lag in past climate change
       @gallopingcamel #24 So you had a speech to give. That speech includes truisms like "causes precedes effects", pseudo-categorical assertions about truisms like "in matters of science, cause precedes effect" and an absurd intent of malicious propaganda on your part like "I persist in my minority (at least on this blog) view that in matters of science, cause precedes effect." which implies that the majority here think something along "effect precedes causes" or "I don't care" or "I dunno". This propaganda is a ridiculous pursue, as this is written -you seem to have forgotten that- and everybody's comments -and backgrounds- are here to see. You have just written something that -said perhaps aloud with projected voice and in the absence of recorders- may have an effect on audiences sensible to those kind of verbal sedatives. Contrary to most people here, I don't think you are willing to follow any argumentation and provide proper critic. You have some designed messages to sow (they don't get money ... in comparison, Stalin was Mother Theresa) and nothing but such kind of messages to sow.
99286. Bob Lacatena at 03:07 AM on 6 January 2011
       Understanding the CO2 lag in past climate change
       38, apiratelookat50,

       (too many to list)

       Well, not really... :) See post 37.
99287. apiratelooksat50 at 02:52 AM on 6 January 2011
       Understanding the CO2 lag in past climate change
       So, Sphaerica @ #34, I think we agree. Orbital changes can initiate global cooling or warming, but other complex factors (too many to list) affect the rate, intensity and duration of these changes.
99288. Bob Lacatena at 02:51 AM on 6 January 2011
       Understanding the CO2 lag in past climate change
       #35, les,

       ...rather than simple "cause precedes effect" type changes?

       Let's have some fun, and look at all of the causes and effects:
       • Multiple orbital changes (orbital shape and inclination, axial tilt and precession, apsidal precession) occur in just the right combinations.
       • These alter the length/strength of the northern hemisphere summer past a tipping point.
       • Winter snow/ice cover on the northern continents does not melt back far enough during the summer.
       • The northern hemisphere albedo changes, reflecting more sunlight back into space, cooling the planet.
       • Atmospheric CO₂ is absorbed by the cooling ocean, reducing the GHG effect, and cooling the planet.
       • The snow/ice melts even less.
       • The albedo increases further, and the planet cools more.
       • Even more CO₂ is absorbed by the ocean (and, I've always presumed, more vegetation is covered with snow/ice without a chance to decay and return to the atmosphere), cooling the planet even more.
       • With the drop in global temperatures, atmospheric H₂O also drops, further reducing the GHG effect.
       • The planet cools even more.
       • The cycle continues -- cooling -- more ice, higher albedo, less CO₂, less H₂O -- more cooling.
       • Eventually, the expanding snow/ice extent reaches a latitude where summers are simply too long/warm for it to remain, and the process halts -- in a new glacial period that will last until the orbital forcings alter again, to run the entire "program" in reverse.
       How very simple!

       Well I'll be!

       :)
99289. garythompson at 02:37 AM on 6 January 2011
       Understanding the CO2 lag in past climate change
       thanks so much to many for your replies to my questions in #12. to reply to Marcus #19, let me clarify by what i meant by 'temps stable'. i'm not attempting to go OT here and talk about weather stations, GISS data, etc. i was sticking to the graph in figure 1 of this post. if you look at the temperature line, for about the last 10,000 years our temperatures have seemed to be in a noisy region and while it is oscillating, it appears to be flat and uncharacteristic of anything else over the past 400,000 years of this ice core data. why is that? to me, it's the most obvious feature of this graph and everytime i see it i ask that same question. oh, one more. the temperature axis is in units of temperature change (C). What is the base period that it uses for the zero change? and i second some of the comments stating that ice core data might have some issues with accuracy. i have the same reservations with tree ring data as well. maybe it is my ignorance in how these tree rings and ice cores are extracted, measured and then how these measurements are translated into degrees C and ppm CO2. if anyone has a good source for that i'd enjoy reading that.
99290. les at 02:33 AM on 6 January 2011
       Understanding the CO2 lag in past climate change
       #34 Are you saying that changes, like entering or exiting ice-ages, are kind of interlocking auto-catalytic & feed-back loops, rather than simple "cause precedes effect" type changes? Well I'll be!
99291. birdbrainscan at 02:25 AM on 6 January 2011
       An online resource for the IPCC 4th Assessment Report
       I also like the search by author, and the preset example for Schneider, e.g. It is evident that keying on author name as cited breaks up a single person into several entries, one for each way of abbreviating, even whether the initials are followed by dots or not. As for paper citations, it looks like you already matched them up to their unique DOI. If the citations are keyed on DOI, that would readily show up all the many cases of the same paper cited in subtely different ways. you could display a list of unique DOIs, and under each one show different cites to it, though I think only people like you and I would be very interested in how the citations vary internally... have you looked at linking back to the places in the body of the AR where the works are cited? That would be really powerful for research if it could be done. I guess it might require reverse engineering either the HTML or the PDF of the reports, to follow the footnote numbering.
99292. Bob Lacatena at 02:19 AM on 6 January 2011
       Understanding the CO2 lag in past climate change
       apiratelooksat50

       Why can't the cooling phase be initated by changes in orbital cycles?

       I'm not sure what your point is. This statement is of course true. The glacials (cold) and interglacials (warm) are both initiated by changes in orbital forcings. Those orbital changes are not, however, enough to cause the changes seen. Something else (CO2) needs to play a major role. Interestingly, too, contrary to the overly simplistic view that most people take, the orbital change isn't one of "warmer" or "cooler" for the planet as a whole. That is fairly constant. What actually happens to initiate a glacial period is that northern hemisphere summers change in a way to become cooler and shorter, so that the previous winter's snow and ice extent (in the northern hemisphere) doesn't have the time or energy to melt back. This changes the planet's albedo, reflecting back more sunlight, and that is what makes the planet cooler. But not enough to actually cause a glacial. For that, something else has to happen.
99293. birdbrainscan at 02:17 AM on 6 January 2011
       An online resource for the IPCC 4th Assessment Report
       Fantastic site, Mila -great work! i really like the list of cited journals ranked by citation counts. Do you happen to have a number for the total of unique journal papers cited for the whole AR4? it should just be the sum of all the counts for different journals listed. On mobile safari on iPad I cannot view the pop-ups for the journal name links, even after i unchecked "block pop ups" in Safari prefs. On Windows Chrome they work fine of course.
99294. Eric (skeptic) at 01:41 AM on 6 January 2011
       Understanding the CO2 lag in past climate change
       #24 gallopingcamel, I'm not sure what you are accomplishing here. You apologized for being rude, but then proceeded to another completely off-topic generalization (research money). You did not support your cause-effect claim in any way, just repeated it. You appear to be ignoring the simple fact that nobody here disagrees that warming causes increases in CO2.
99295. apiratelooksat50 at 01:41 AM on 6 January 2011
       Understanding the CO2 lag in past climate change
       I teach environmental science and my students long ago picked up on the CO2 lag. (I know we are talking about high school kids, but oftentimes a simpler, uncluttered insight is valuable. Kind of like Occam's Razor). When they initially saw the chart, their consensus was "that something else is affecting both". Now that this article supports the initiation of the warming phase by changes in orbital cycles, their next question is: "Why can't the cooling phase be initated by changes in orbital cycles?" This is not skepticism on their part, but inquiry.
99296. apiratelooksat50 at 01:33 AM on 6 January 2011
       Understanding the CO2 lag in past climate change
       Rob Painting @ 21: I'm not supporting anyone's stance, but it should be pointed out that there is a difference between BIODIVERSITY and BIOMASS. Biodiversity refers to number of species. Biomass refers to the total mass of living biological organisms at any given time and place. I don't have a clue about the biomass at that time, but your chart is not applicable.
99297. Bob Lacatena at 01:31 AM on 6 January 2011
       Understanding the CO2 lag in past climate change
       lugree,

       I'm a rank amateur, but I'd question the accuracy of the ice core...

       The subject of interpreting ice cores (or any such proxy data) is far more complex than your brief description implies. More importantly, the people that work with them are very, very, very smart, and have spent much of their professional careers dedicated to the subject, not just a few minutes while reading a blog. So you have two choices. You can just accept what the experts say, or you can study intently to understand what you are talking about. The third alternative, which is to simply say "I'm a rank amateur, but..." is not an option. That's a cop out. You can't have a strong opinion about something that you admittedly don't understand. A very simple starting point: Wikipedia Unless and until you at least get through that, you are unjustified in casting aspersions on the validity of the data.
99298. Bob Lacatena at 01:18 AM on 6 January 2011
       Understanding the CO2 lag in past climate change
       gallopingcamel,

       cause precedes effect

       Of course it does. Do you also insist that every effect can have exactly one and only one cause? Do you also insist that every cause can produce exactly one and only one effect? Do you also insist that a cause can never be the effect of something else, and an effect can never cause anything else? Or is it possible that the world is a complex place, and that to resolve situations one must use intelligence and difficult thought, and consider more intricate processes than the merely childishly simplistic? Part of what I take from your comments is that you either did not bother to read or simply did not understand the original post. You need to go back and try again, with a skeptical point of view (i.e. not with the mindset of one who already knows that what he hasn't read is wrong, and therefore has no need to focus on what is actually written). Your own logic equates to "my father died of cancer, therefore I will die of cancer, therefore I am invincible to everything but cancer." You need to study the situation much more intensely if you are to have a viable opinion on the subject.
99299. Arkadiusz Semczyszak at 01:14 AM on 6 January 2011
       Understanding the CO2 lag in past climate change
       @lurgee ... it's doubtful how accurately thousands of years of variation can be recorded in a few metres of ice ... You're right - it actually can be a problem. I recommend the discussion here. I warn You - it is very long. CO2 is not correlated with the temperature - at the time - also in the Holocene and the Historic Time (Anno Domini). It was found from 50 (Frank et al., 2010.: “... with a 50-year CO2 response lag—such timing is consistent with modelled CO2 response to a temperature step change.”); to 250 years difference.
99300. Anne-Marie Blackburn at 01:04 AM on 6 January 2011
       Understanding the CO2 lag in past climate change
       gallopingcamel

       That said, I persist in my minority (at least on this blog) view that in matters of science, cause precedes effect. Therefore, the hypothesis that rising temperatures cause CO2 concentrations in the atmosphere to rise is more plausible than the reverse over the periods covered by ice core data.

       Unless I'm mistaken and missing your point, this is what I said in my OP. I then took it a step further by saying that increasing CO2 levels cause further warming which again releases more CO2 - i.e. increasing CO2 levels become the cause and effect of further warming.

       I have a general objection to "Climate Science". Researchers with hypotheses linking climate catastrophe to the actions of mankind are likely to be showered with money by governments around the world. Scientists who have opposing views are marginalized and de-funded. I call this the "New Lysenkoism" and it is more dangerous than Stalin's version.

       Do you have any evidence to support this? Any evidence that sceptic scientists have lost funding? How do you then explain contrarians such as Lindzen, Spencer and Soon publishing in the scientific literature?

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