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Doug Bostrom at 07:55 AM on 4 August 20101934 - hottest year on record
Broadlands: It would be absurd to think that some sort of conspiracy has taken place but some plausible explanation should be available for this consistent trend. I'll be you're right. Why not just ask?: "Questions? For all climate questions, please contact the National Climatic Data Center's Climate Services and Monitoring Division: Climate Services and Monitoring Division NOAA/National Climatic Data center 151 Patton Avenue Asheville, NC 28801-5001 fax: +1-828-271-4876 phone: +1-828-271-4800 email: ncdc.info@noaa.gov To request climate data, please E-mail:ncdc.orders@noaa.gov " -
chris at 07:52 AM on 4 August 2010Plant stomata show higher and more variable CO2 levels
David, I'd say the science is pretty straightforward, especially with respect to Geocarb and AIRS: Geocarb: Geobarb has essentially nothing to say about absolute atmospheric [CO2] levels during the ice age cycles represented in deep Antarctic cores. Here’s what Berner says about his Geocarb model with respect to absolute values of his modelled [CO2], and the temporal resolution [***]:” Results are expressed as RCO2 which is defined as the ratio of mass of CO2 in the atmosphere at time t divided by the mass at present, and the results are compared to a standard run, where best estimates of the various input parameters are used. To convert RCO2 to CO2 concentration, because of appreciable errors inherent in this kind of modeling, a rough value of 300 ppm can be used to represent “the present.””
And:”It should be emphasized that GEOCARB modeling has only a long time resolution. Data are input into the model at 10 my intervals with linear interpolation between. In the case of rock abundance data, averages for up to 30 my time slices are sometimes used. Thus, shorter term phenomena occurring over a few million years or less are generally missed in this type of modeling.”
Clearly the model (which is constructed to assess weathering-dependent carbon cycling during the Phanerozoic) doesn’t attempt to determine precise [CO2] levels (”because of appreciable errors inherent in this kind of modeling, a rough value of 300 ppm can be used to represent “the present.”). And since it has 10 million year resolution with linear interpolation (up to 1 mya resolution in the Geocarbsulf version I linked to above), it can’t really say very much about the [CO2] levels during the ice age cycles. That’s pretty clear isn’t it David? We should take account of what the inventor of the model says about his model! AIRS and graces: You point out that daily AIRS retrievals can show lower mid-tropospheric [CO2] at the poles than at mid-latitudes. In monthly averages the differences are smaller (and it depends on the month of course, sometimes the polar regions have higher [CO2] than mid-latitudes). So why not take your point to its logical conclusion? Averaged yearly the differences are small (a few ppm). Since, in assessing fossil leaf stomata, or ice cores, the data is at least yearly averaged, we really should consider yearly-averaged AIRS data in assessing any difference between globally averaged and polar [CO2], yes? In which case your argument based on daily or monthly AIRS retrievals has little merit. stomata: Yes, there are apparent differences in some of the stomatal [CO2] reconstructions compared to the [CO2] measured in Antarctic cores. We all agree that [CO2] in ice cores are temporally averaged. For the high resolution Law Dome core, some stomatal data are in broad agreement with the ice core data, and some differ. In all cases the stomatal scientists highlight rather large uncertainties in their data. At some point the stomatal scientists will no doubt come to some consensus about the best methods for addressing the fossil stomatal data. Otherwise, one needs to be very careful not to over-interpret stomatal data. They have very large associated uncertainties (this is obvious from inspection of the training sets used to generate calibration curves). Since there is no absolute relationship between [CO2] and stomatal indices, the data can only be used for species that still exist today (in order to calibrate the particular analysis), and one has to make the assumption that the physiological response to varying [CO2] is the same 100’s of 1000’s to millions of years ago, as now. Fossil plant stomatal analysis is a nice method for estimating low resolution [CO2] levels and changes in the deep past. But there isn't really a basis for discounting ice core data in favour of stomatal data. Apart from anything else it’s difficult to imagine a process that would give rise to a depth-independent 20% reduction in [CO2] levels that is exactly constant between numerous different high resolution and low resolution cores through 1000’s of metres of ice. [***] R. A. Berner and Z. Kothavala (2001) Geocarb III: A Revised Model of Atmospheric CO2 over Phanerozoic Time American Journal of Science 301, February 182-204. -
Adam C at 07:46 AM on 4 August 2010Has Global Warming Stopped?
#43 fydijkstra: Actually, a linear model is appropriate. The combination of the logarithmic relationship of forcing to concentration with the exponential increase in concentration over time should be expected to create a roughly linear relationship between forcing and time. If you're unsatisfied with the fit, filtering out some of the noise makes more sense (given the underlying physical theories) than simply increasing the polynomial power. Correlation, as we are constantly reminded, does not prove causation. -
Broadlands at 07:45 AM on 4 August 20101934 - hottest year on record
JMurphy and Doug... OK. Here are some numbers. The first column shows weighted monthly temperatures for the 48 contiguous states (no Hawaii or Puerto Rico) derived from the original 1921 US Weather Bureau monthly reports... the Tables in the Condensed Climatological Summary. Example: http://docs.lib.noaa.gov/rescue/mwr/049/mwr-049-12-0684.pdf The average temperature (°F) for each state is given in these official reports. Only the contiguous 48 are used. The second column gives the temperatures from the NCDC-NOAA 1895-2009 US database where, presumably, the same historical information is given for each state, each month. The third column is the amount that the NCDC has lowered each temperature. JAN 36.0 33.8 2.2 FEB 38.5 35.9 2.6 MAR 49.5 47.5 2.0 APR 53.7 52.2 1.5 MAY 61.9 60.5 1.4 JUN 72.1 70.8 1.3 JUL 76.1 75.3 0.8 AUG 73.0 71.6 1.4 SEP 69.0 67.7 1.3 OCT 56.4 54.9 1.5 NOV 44.7 42.9 1.8 DEC 36.7 34.5 2.2 YEAR 55.6 53.9 1.6 Note that the annual average for 1921 has been lowered by 1.6°F. This lowering has the net effect of removing the year 1921 from its position as the warmest year on record in the US... as the Weather Bureau observed in several annual reports I cited earlier. The same pattern of lowering can be found in other years. I've checked 1934, 1938, 1940. All of the original Weather Bureau temperatures have been systematically changed and all have been lowered. The winter months have been lowered more the summer months...every time. It would be absurd to think that some sort of conspiracy has taken place but some plausible explanation should be available for this consistent trend. -
Doug Bostrom at 07:45 AM on 4 August 2010Has Global Warming Stopped?
Regarding Al's pointer to The Register (At it again, El Reg? Steven Goddard jilted 'em but they're discouraged...) there's a much fuller treatment here though the full text still seems locked away: Signs of reversal of Arctic cooling in some areas -
Peter Hogarth at 07:39 AM on 4 August 2010Plant stomata show higher and more variable CO2 levels
David Middleton at 07:00 AM on 1 August, 2010 “AIRS shows higher mid and low latitude CO2 levels than ice cores show for Antarctica” Slightly: Check out these recent visualizations of global CO2 measurements, but look at the Arctic values. You then state: “That the ice cores are not resolving decadal and century scale CO2 variations very well and that CO2 levels recorded in Antarctic ice cores should yield lower values than just about any other method used to estimate past global CO2 levels” I disagree. The following data from six different cores post dates that used in Van Hoof somewhat.(Source NOAA Paleo Ice core data).
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Waste heat vs greenhouse warming
RSVP: Emissivity equals absorptivity for an object in thermal equilibrium. Please read that link - nothing is a perfect black-body (although the ocean is close), emission curves may be smooth (gray-body) or spiky (GHG's, many minerals), but all scale like a theoretic black-body with temperature. If we didn't have any greenhouse gasses in the atmosphere, the Earth would be 33C colder, as the Earth radiated directly to space through the IR transparent atmosphere. The atmosphere would also be colder, as it would only be heated by conduction/convection, no IR. GHG's only warm things up by absorbing IR leaving the planet, sending half the thermal energy they have back at the Earth (radiating energy in an isotropic spherical distribution), instead of letting it go out to space, thereby reducing the total emissivity (emission spectrum) of the Earth. And more GHG's mean more warming. Period, end of story. No cooling, unless you count the stratosphere cooling because all the heat is being kept close to the surface of the earth. You have failed to do the most elementary reading on greenhouse gasses or emissivity, thrown around red herrings such as the 'double-slit experiment', made incorrect claims about energy cancellation in microwaves, ignored the measured energy flows of the Earth/atmosphere system to argue for convection, and not understood thermal diffusion in a gas. If you are not just trying to crank people up, you are certainly failing to understand the information we have pointed you towards. I think this will be my last post on this topic. -
Al2807 at 07:05 AM on 4 August 2010Has Global Warming Stopped?
I found this article http://www.theregister.co.uk/2010/08/02/arctic_treering_cooling_research/ I'm sure there's more than the article says, since it appears to give the impression of an study to back up the idea that climate change is only due to solar activity. But I'm not a subscriber of the magazine that contains the full paper. http://instaar.colorado.edu/aaar/browse_abstracts/abstract.php?id=2668 Can anyone with access have a read and comment about the paper itself?. -
Chris G at 06:52 AM on 4 August 2010Why I care about climate change
John @63, Coincidentally, there is a psychological term for refusing to accept unpleasant information. It is classified as a defense mechanism and is called denial. RSVP @69 and DCWarrior @64, Another avenue to consider is that it isn't necessarily the scientists telling rich people they have to give up their treasures. I suspect that is at least in part a ploy by the very rich, (I read somewhere that the fossil fuels industry controls around 20% of the world's wealth.), to convince other people to pursue a strategy that contributes to the wealth of the very wealthy for as long as possible. A fair number of the studies that report that doing something to reduce carbon emissions will wreck the economy have been funded by those making a great deal of money from the sale and use of fossil fuels. ("If you do what they tell you, you'll have to give up your toys! They are evil and wrong!") Be skeptical, be very skeptical, but consider both sides when you are asking why is this person telling you what they are telling you. Also, rich is relative. If you are sitting on an air-conditioned building while reading this, you are richer than 75% of the world's population. -
macwithoutfries at 06:39 AM on 4 August 2010Has Global Warming Stopped?
The other thing that I was expecting would have been that 15 years is the WRONG INTERVAL - the correct interval is at least 22 years (or multiples of 22 years) and I believe you will see far more significance if you do the analysis like that !!! -
Phil at 06:38 AM on 4 August 2010Why I care about climate change
Albatross @76 Yes, it has occurred to me since my last post that since EWM only measures the difference between winter and summer mortality, then a low EWM is not necessarily a good thing, since it would rise with a very low summer mortality! Clearly the EWM for 1999-2000 was due to excess alcohol consumption over the millenium celebrations :-) -
Ned at 06:33 AM on 4 August 2010The Past and Future of the Greenland Ice Sheet
philc writes: Both the mentioned papers talk about "mass balance" but unfortunately apparently don't include any discussion of the input side of the equation. Has there been any measurement of the amount of precipitation? Has it changed? Why? Yes, there has. Check out van den Broeke 2009, which was prominently featured in John's earlier post Why is Greenland's ice loss accelerating? In particular, the following figure from that paper shows a time series of the various components of surface mass balance. Note that prior to the 1980s, SMB was mostly influenced by changes in precipitation rather than in surface melting/runoff. In recent years, precipitation has been higher than in the past, but runoff has been even greater, leading to a negative surface mass balance. (This is independent of the other mass balance term, discharge of ice via calving).Surface Mass Balance (blue) and its components precipitation (red), runoff (orange) and sublimation (green).
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Marcel Bökstedt at 06:33 AM on 4 August 2010Why I care about climate change
John Cook>Thanks for the personal declaration! I think that this is one of the most usuful places on the net for learning about what science can say about climate change. I've come here here from a different direction from you. I'm a mathematician, and I would like to make up my mind on whether things are really as bad as they seem, and on whether mathematics could be of any help in supporting climate research. Some people actually seem to think that it might be: MSRI , Azimuth. -
Albatross at 06:31 AM on 4 August 2010Why I care about climate change
Phil @ 72, "I would also note that the graph in #55 does not, to my recollection, correlate well with cold UK winters, in particular 1999/2000 was not a cold winter." You are correct, the 1999-2000 winter in the UK was mild, with an anomaly for Dec-February of about +1C (from GISS). The temperature in March 200 was also above average, with an anomaly of +1 C. All anomalies wrt to the 1961-2000 mean. Intriguing then that the "excess winter mortality" for 1999-2000 was the highest of all the winters shown-- factors other than temperature are definitely at play and this statistic is, IMHO, not worth much, except to be used by contrarians to misinform and confuse. -
Daniel Bailey at 06:20 AM on 4 August 2010Visually depicting the disconnect between climate scientists, media and the public
FWIW, Real Climate has an interesting post from Anderegg et al., here. The Yooper -
Chris G at 06:19 AM on 4 August 2010Why I care about climate change
Oh, no matter, but I would take a different outlook at John's response at #22. Time and space don't require matter to exist, but matter does require time and space. -
Peter Hogarth at 06:16 AM on 4 August 2010Has Global Warming Stopped?
fydijkstra at 06:03 AM on 3 August, 2010 Now try your analysis but with updated HadCRUT3v values to June 2010, with same start dates. Surprised? worried? Now try a 2nd order fit for your trend since 1960, and look at the R squared value. Is this better than the 4th order fit? Discuss. Now plot the error bars. Let us know what you find. -
Phil at 06:14 AM on 4 August 2010Why I care about climate change
Further to my last post, it appears that UK has similar excess winter mortality to Greece, Portugal, Italy and Spain, all of which are much higher than those for Germany, Norway, Sweden and Denmark. This would suggest an inverse relationship between cold winter temperatures and the EWM ? -
Phil at 05:57 AM on 4 August 2010Why I care about climate change
As a UK citizen, I have to comment on the discussion on the excess winter mortality figures, although I'm afraid I can't claim any specific expertese ! Certainly UK winter are relatively warm for the latitude - Edinburgh is the same latitude as Moscow, but has much warmer winter temperatures. UK winters are usually milder than the European Continent. Reasons for the high figures: I would suggest that poor thermal insulation of our (relatively old) housing stock could be significant and I wonder whether a relatively high degree of homelessness (usually accompanied by alcohol/drug problems) might also contribute. I would also note that the graph in #55 does not, to my recollection, correlate well with cold UK winters, in particular 1999/2000 was not a cold winter. -
David Middleton at 05:57 AM on 4 August 2010Plant stomata show higher and more variable CO2 levels
If you "can't imagine a real world example where" skepticism and debunking have meaning, you've probably never been an exploration geologist or geophysicist in the oil industry. Our "experiments" (exploration wells) are rather expensive. Every "hypothesis" (prospect) is subjected to a lot of skepticism and debunking before we run the main experiment. GeoCarb is based on a model derived from weathering rates and other geological factors. It says that the atmospheric CO2 concentration, averaged globally over the last 10 million years, has been about 267 ppmv. Contemporaneous plant stomata studies show CO2 oscillating between 270 and 360 ppmv over that same time period. Which is very similar to their oscillation range in the Sangamonian and Holocene. The average CO2 level from the ice cores is about 231 ppmv over the last 800,000 years (generally oscillating between 230 and 310 ppmv). This is 36 ppmv below the GeoCarb global Neogene average. Both GeoCarb and plant stomata show higher average CO2 levels than the ice cores do over the Neogene. The stomata data show much more variability in CO2 levels during the two most recent interglacials. We can quibble all day long about the AIRS data... But the daily images show that the polar regions have 10-20 ppmv lower CO2 levels than the mid to low latitudes and the monthly averages show the polar regions to have 5-10 ppmv lower CO2 levels than the mid to low latitudes. "The Science Says" Plant stomata show higher and more variable CO2 levels than ice cores. "The Science Says" GeoCarb and plant stomata show higher CO2 levels than ice cores. "The Science Says" AIRS shows higher mid and low latitude CO2 levels than ice cores show for Antarctica. "The Science Says" That the ice cores are not resolving decadal and century scale CO2 variations very well and that Co2 levels recorded in Antarctic ice cores should yield lower values than just about any other method used to estimate past global CO2 levels. -
RSVP at 05:54 AM on 4 August 2010Waste heat vs greenhouse warming
KR #174 As far a how black bodies work,,, they emit as readily as they absorb, so unless this is established, we shall have difficulty discussing this topic. -
fydijkstra at 05:54 AM on 4 August 2010Has Global Warming Stopped?
Some answers to the comments on my comment #20 Dikram Marsupial: “It is entirely possible that a linear model works rather well after the effects of ENSO have been filtered out.” Yes, that’s possible, but that’s not the subject of this discussion. The only thing that Aldin Griffith shows is that, with statistical arguments, we cannot say that global warming has stopped. I show, that the data fit better to a flattening non-linear trend. By the way, a linear model is not the most appropriate in the case of infrared absorption by a greenhouse gas, because the absorption has a logarithmic relationship to the concentration. David Horton: (1) “Only the deniers managed to keep their nerve while all around were losing theirs.” Who is speaking here about denying? I denied nothing. I only showed that the data fit better to a flattening curve than to a linear curve. (2) “there is no mechanism presented for explaining how the change in global temperatures could be polynomial rather than linear. Where is the negative feedback that takes CO2 back out of the air once it reaches a certain concentration?” That’s true, but a polynomial function is pretty well able to describe (part of) a saturation curve. And there are plenty of mechanisms that can explain why the output of natural processes gradually grows to an equilibrium (plant growth, microbial growth, absorption of radiation, water vapour content of the air, etc.). (3) “Where is the negative feedback that takes CO2 back out of the air once it reaches a certain concentration?” CO2 is not taken out of the air when it reaches a certain concentration, but the effect of CO2 decreases when the concentration increases. Possible negative feedback mechanisms are the formation of clouds, increased growth of plants and algae. But I do not pretend to know which effect has caused the flattening of the temperature curve in the last decade. I only show, that a flattening trend fits better to the data than a linear trend. Apeescape: (1) “an n-1 polynomial can fit a dataset of n points, so R^2 is really not a valid measure of comparison in any situation. The adjusted-R^2 may be a little better.” A very high order polynomial function can fit every dataset, but that is not what I did: we have 15 data points, or 50, and I only used a 4th grade polynomial. In such a case (number of data >>polynomial grade) R^2 is a valid measure for the spread of the data around the trend line. (2) “IOW, if you pick a different range of dates (even w/ same sample size) to do the same analysis, your results won't be as robust.” If you mean, that with longer time series the flattening after 1999 disappears, you are right. I also tried the trends 1901-2009 and 1850-2009, and in these cases the general rise in the past century overwhelms the flattening in the last decade. But in all cases the polynomial trend fits better (higher R^2) to the data than a linear trend. Kdkd: “What you're doing there with your polynomial fit is almost certainly something called overfitting. This is where your model is describing the noise component of the relationship rather than the signal.” No, see my first answer to Apeescape. It would be overfitting if I used a 15-grade polynomial to describe the trend of 15 data points, but that is not what I did. With a 15-grade polynomial we could even fit the effects of El Niño and the eruption of a volcano. With a 4-grade polynomial these incidents remain part of the noise. Dark Skywise: “Since we're not even close to a theoretical maximum (like, how hot would the Earth get with a 100% GHG atmosphere?), more-or-less linear trends can continue for quite a while.” The maximum of the effect of greenhouse gasses could be much closer than you think. At sea level the effect of CO2 is already saturated. Only in the higher troposphere, where the air pressure is much lower, has an increase of CO2 effect on the infrared absorption. So it would not be surprising if the temperature does not increase ever and ever. -
JMurphy at 05:54 AM on 4 August 2010Has Global Warming Stopped?
You noticed it too, doug_bostrom, i.e. the Gore obsession. That certainly does reveal a lot about Doug Proctor. So too do the assertions about "natural warming", "pre-CO2 impact warming", "adjustments are a significant portion of the "anomalies"", "data adjustments during that time period amounts to 0.4C", "if an incorrrectly applied UHIE has biased the temperature readings upward by 0.15*C", "it is only the post 1960s warming we are to associate with CO2", "the "death spiral" of the Earth" Oh, and the lack of credible facts and figures ! Care to show some, Doug Proctor ? -
RSVP at 05:51 AM on 4 August 2010Waste heat vs greenhouse warming
KR #173 I read what you wrote. I agree with everthing you say. However when you talk generally about waste heat, I am not sure where this is coming from specifically. My thought is that N2 and O2 are heated (atmospheric waste heat), or water supply (thermal water pollution). The N2 and O2 (i.e. non-GHGs that make up 97% of air) can either convect to the land, water or ice, or loose their heat via thermo-vibrational translation to GHGs, which in turn emit this energy via IR. In this case, GHG help remove waste heat, but this is not the typical channel (surface to GHG) that is normally modeled. -
Sheila at 05:43 AM on 4 August 201010 Indicators of a Human Fingerprint on Climate Change
@Bern I live near a major astronomical observatory, on La Palma, in the Canary Islands. I asked the head of one of the solar telescopes here (the Dutch Open Telescope http://en.wikipedia.org/wiki/Dutch_Open_Telescope) for his opinion on global warming. He said that he's not qualified to say what's causing it, but it's certainly not the sun. The sun has been unusually cool for the last 50 years or so. He must know what he's talking about. -
Albatross at 05:39 AM on 4 August 2010Why I care about climate change
Dappledwater @70, You may be right. Either way, the citing that graph as evidence as BP is, IMHO, very misleading. -
Rob Painting at 05:36 AM on 4 August 2010Why I care about climate change
Albatross @ 66 - in the absence of any kind of analysis of the winter deaths, and I can't be bothered researching it myself, I'd have thought the spike in deaths would mainly be due to cold and flu viruses being more prevalent in winter. That's the case down here in the Southern Hemisphere anyway. -
RSVP at 05:35 AM on 4 August 2010Why I care about climate change
dcwarrior #64 If anyone is in a position to retool (materially), it is the rich. -
Albatross at 05:29 AM on 4 August 2010Why I care about climate change
Thanks CBDunkerson @67. Wow, that is some time ago.... I see that my final hyperlink @ 66 did not work. Here it is -
Doug Bostrom at 05:26 AM on 4 August 2010Has Global Warming Stopped?
Just as a general remark Doug Proctor, the instant you mention Al Gore in an argument you distract your audience by introducing political content having nothing to do with science. More, if you're concerned with making a scientific argument your speech loses credibility because many people reading your words will realize you're bringing an ideological slant to your treatment. ...the predictions of disaster are modelled on a) the temperature data is 95% accurate, 2) no other significant "natural" temperature forcing mechanisms are working today, and 3) that human usage of fossil fuels will increase throughout this century as it did in the last part of the previous century. All apparently true so far, with the caveat that even if we were somehow to stop using fossil fuels today we'd see significant warming for a long time to come. -
Doug Bostrom at 05:00 AM on 4 August 2010Grappling With Change: London and the River Thames
Oops, forgot Michael Sweet! I don't know specifically about New Orleans or Miami. While digging for material for this piece I did run into planning materials for other places and I'll say my impression is that the British are exceedingly competent at pulling together vast amounts of information and synthesizing it into documentation suggesting coherent plans of action, probably close the best-case example. Their competence in this regard is actually rather staggering. Cameron should think twice about blowing up such a structure, shouldn't carelessly carve into the civil service there. What I can say regarding such places as Miami and New Orleans is that here in the U.S. the curious asymmetry between local and national governmental units is also visible. Where I live the department of transportation is taking into account sea level change when planning major roadway improvements, for instance, while meanwhile the farther up we go in government the more vague and amorphous the response. But I don't see the same scope of coherence and involvement visible in the U.K. My intuition suggests that Miami and New Orleans will suffer "death by a thousand cuts" if sea level goes the way it seems to be headed. The process already seems to have started in New Orleans though of course Katrina was not necessarily an outcome of climate change-- a city partially below sea level in an area affected by hurricanes is a dubious proposition at best. New Orleans has suffered what appears to be a permanent population loss, another storm will of course inevitably mess with New Orleans and it's not hard to picture more people giving up. Rinse and repeat. Enough population loss and eventually it'll lose the political clout to attract federal dollars for protection. -
Doug Proctor at 04:57 AM on 4 August 2010Has Global Warming Stopped?
That the Earth is warming is neither here nor there when it comes to AGW-CO2 discussions. The point in all this debate is whether the warming is man-made and man-controllable vis-a-vis CO2 reductions from fossil fuel usage. The input of CO2 is not considered a factor in temperature rises by warmists or skeptics until the period of 1965 or 1975. Graphs showing warming prior to this period show "natural" warming ASSUMED to have stopped to any significant level in the '65/'75 times. This is certainly an assumption without evidence, for the inclusion of some pre-CO2 impact warming is to reduce the effect of fossil fuel CO2 currently and to take away some of the "catastrophic" temperature rise. It would also serve to kill the more outlandish of the IPCC temperature rise modelling efforts. "Warming" per se is not the issue. Is the warming since the '60s following the IPCC CO2 models? Is the temperature data we are using corrected properly? The adjustments are a significant portion of the "anomalies". We are alarmed by a very small difference in the day-to-night, summer-to-winter variation, after all, and must have exceptionally good data to have confidence that what is purported is good. The confidence level of the IPCC reports is about the mathematics used to identify the change in the data involved, NOT the quality of the data being used. A 95% confidence in a 0.7C* change since 1960 is misleading when data adjustments during that time period amounts to 0.4C*: if an incorrrectly applied UHIE has biased the temperature readings upward by 0.15*C, then what does a 95% certainty mean? A temperature rise of 0.55C* (taking but one non-CO2 effect into account) devastates the AGW argument, as the catastrophe either no longer exists or is one to require us to burn INCREASING amounts of oil and gas for 300 years. Remember that the IPCC and Gore disaster is based on an expanding human population and industrialization that will rocket our use of fossil fuel even while those resources are limited and, as many think, past their peak. We lose track of the argument that it is only the post 1960s warming we are to associate with CO2, and that the predictions of disaster are modelled on a) the temperature data is 95% accurate, 2) no other significant "natural" temperature forcing mechanisms are working today, and 3) that human usage of fossil fuels will increase throughout this century as it did in the last part of the previous century. I suggest that each of these assumptions is questionable, and together they make the "death spiral" of the Earth a proposal more to help Mr. Gore buy more seaside mansions than to make Mrs. Gore buy an electric car. -
Has Global Warming Stopped?
robhon #7, tobyjoyce #38 - For myself, I've always phrased it as "Hindsight consists of looking at an ass"... -
tobyjoyce at 04:42 AM on 4 August 2010Has Global Warming Stopped?
robhon #7, The French have a word for it: l'esprit de l'escalier, roughly "the wisdom of the staircase". It is the hindsight we have on the way back down the stairs i.e. too late. Or, as someone misquoted Robbie Burns: The best said words of mice and men Are those we did not think of then -
CBDunkerson at 04:40 AM on 4 August 2010Why I care about climate change
Albatross #66 wrote: "When did we last have a record cold year (or month) globally?" According to GISS the years 1890, 1907, and 1917 are tied for the lowest global temperate anomaly at -0.39 C. The global monthly lows are; Jan: -0.82 C in 1893 Feb: -0.58 C in 1893 Mar: -0.49 C in 1911 Apr: -0.48 C in 1911 May: -0.55 C in 1917 Jun: -0.43 C in 1907 Jul: -0.39 C in 1912 Aug: -0.52 C in 1912 Sep: -0.45 C in 1912 Oct: -0.52 C in 1912 Nov: -0.51 C in 1890 Dec: -0.69 C in 1917 So the most recent global record lows (for May, December, and the entire year) were in 1917. Not quite a century ago. -
nhthinker at 04:27 AM on 4 August 2010On Consensus
As an engineer, I understand all about noise. Noise can be averaged out if what is being looked for is long term trends. If the noise can not be averaged out for the time frames you are concerned with, then you can't make supportable claims about the accuracy of the underlying signal. Best judgement in the 70s was CO2 doubling would be 2 to 4 degree C change. It was also contemplated that the Earth's response to elevated CO2 would be linear or that it might trigger some damping response or multiplying effect within the complex interworkings of atmosphere clouds and oceans in addition to the nonlinear effect in the polar regions. How much have those numbers "tightened up" in the last 45 years? Maybe not at all. How much have we learned about the other effect of increase CO2 or increased temperature as to whether their exists the probably of additional damping or mulitplying effects of sustained higher temperature? Not much, because the changes to the environment (our experiment) is so slow. Repeatability is critical to good scientific confidence. That is what it takes to be a hard science. Climate science is no where near established enough to make repeatable hundred year predictions. I find it humorous that those advocates here will not concede that sciences that involve controlled repeatable tests and relatively short time scales are inherently more reliable than sciences that only involve one object under test and the scientists are too impatient to propose a model and then wait until it is proved out by the data and instead constantly tweak the model much faster than the experiment actually runs. Medical science involves plenty of different independent objects to test and time scales where the scientific impatience does not play as large of role. Is there anyone on this forum that claims to be a climate scientist and would also claim that Climate science rivals medical science in term of its certainty of its hypothesized models tested by repeatable trials by independent scientists? The answer is no scientist worth his salt would ever make such a claim. They might claim climate science certainty is good enough, but it is no where in the same league as medical sciences or physics. The people on this board seem to have forgotten some fundamental principles of science. Those that separate the hard sciences from the softer sciences. There are still huge things to discover about climate science. I totally agree with -
Doug Bostrom at 04:20 AM on 4 August 2010Grappling With Change: London and the River Thames
Thank you JMurphy, I'll take care of that. Chris, glad you enjoyed it; part of my thinking in doing this was that we talk a lot of abstractions but there is a continuum between the concepts and concrete. Indeed London is sitting on a bed of slowly-compacting clay, present iteration of the Thames Barrier included this as a factor. More information on the general situation coming up in my response to GC. With the price of real Reggiano parmesan what it is these days, I think I may keep a shovel handy near the refrigerator, just in case. Believe it or not actually thoughtfull I ended up slicing away several hundred words from this thing, it reminded me of the apocryphal Chinese Boeing 707 copy that was too heavy to take off. Yet I found that like an airplane it needed wings, fuselage, tail and engines to work the way I planned. It definitely won't be to everybody's taste, heh! Indeed the whole southern coast of England is sinking dorlomin. The rate varies by location; near London it's dropping at a pretty good clip of 0.5mm/yr. Thank you for the complement, GC. This was fun to write because it was less about direct hectoring with scientific facts, more a casserole. That's really interesting what you say about pumping the aquifer. If you dig into the raft of documents concerning the general hydrological background of London it turns out that they're now doing a bit of a balancing act. Removing -too little- groundwater means they begin to have groundwater flooding problems, -too much- and the subsidence becomes a bigger issue. Reminds me of when I lived in Atlanta Georgia and ignorantly placed a dehumidifier in the basement of my home which was sitting on a shallow foundation on red clay. I think you can picture the result! I had to establish a compromise between mildew and throwing of doors, floors etc. -
Albatross at 04:14 AM on 4 August 2010Why I care about climate change
BP @58, Is this really the post where you choose to argue? I would prefer not to, but you make some pretty misleading comments in your post that cannot go unchallenged. Of course it gets hot almost every spring in south Asia before the Monsoon starts. No-one here, incl. John, is to my knowledge disputing that fact. What we are talking about are extreme heat records being broken. And yes, cold can kill too....got it. As for your misleading British graphic, you are assuming that b/c it is for winter that all those deaths are attributed to the cold, but that is not true. They say: “During the winter months, mortality in England and Wales reaches higher levels than during the summer months. A measure of this increase is provided, on an annual basis, in the form of the excess winter mortality figure. This figure is a simple way to assess mortality levels over the winter as a whole. Excess winter mortality is calculated as winter deaths (deaths occurring in December to March) minus the average of non-winter deaths (April to July of the current year and August to November of the previous year).” So those deaths are on account of a multitude of factors, and are not all attributed to deaths because of unusually cold temperatures. Now, the UK Met office does clarify and states that “In the UK there are, on average, 25,000 extra deaths in winter compared to other months of the year — 80% are thought to be due to the cold”. Hardly a clear or quantitative picture. Interestingly, in the USA (between 2000 and 2009) average annual deaths from heat (162) far outnumber those from cold (21), as do deaths from flooding (65).So it seems that people in the UK are not well equipped or educated on how to deal with unusually cold weather. So you citing the UK data (which is misleading) looks like an example of cherry-picked to me. Anyhow, the warmth being experienced now is on a global scale, as suggested by the satellite, radiosonde and surface data. According to the RSS MSU data, July 2010 is now the warmest for July on the satellite record. When did we last have a record cold year (or month) globally?, or when was the last year when the global mean temperature was below the long-term mean? According to NASA GISS, the answer to the latter is 1976—34 years ago. Not surprisingly, 2010 is currently tied with 2007 for the number of national all-time (i.e., on record) highs for nations around the globe: National all-time record high temperatures around the globe in 2010 (including Pakistan which you seem to object to) = 15. National all-time record low temperatures around the globe in 2010 = 1. In 2003 there were twelve and in 2003 eleven and in 1998 nine, all-time record highs. For more go
here -
Doug Bostrom at 03:57 AM on 4 August 2010Visually depicting the disconnect between climate scientists, media and the public
Stylo you're not producing a useful critique. From your remarks it's pretty clear you don't know about survey methodology, you're instead wading into another area of expertise you're missing and pronouncing unfounded judgments. This is a really conspicuous pattern among contrarians. Airily dismissing multiple scientific disciplines to harbor a cherished belief is not a viable argument. -
Chris G at 03:45 AM on 4 August 2010Why I care about climate change
Not much new to add here, but I'll take the opportunity to wax philosophically, and I have a few thoughts: I liked the analogy of balanced weights and adding just a little bit to one side. When we are talking about climate science and climate change, we are not talking about forces that have not existed before; we're just debating effects of changing the balance point. RSVP, John explicitly said the cartoon did not apply; though, even as I write this I find myself drawn into that trap. More energy in the earth system shifts the distribution of rain, regions than were marginally sustainable agriculturally become unsustainable. Regions that had been unsustainable may become so, but there are no farmers living there and the transition will not be without hardship. Think of the effects on crops and people when the temperature reaches the hottest week of the year. Now expand that time out to either side by 2-4 C and raise the temperature in the middle time by the same amount. In case you don't know anything about agriculture, that is really bad for yields. Wheat prices are higher globally now and that could be a result of the heat waves in the Moscow region. Fortunately, the US has had a really good year for wheat. What happens if/when the weather dice become loaded to the point when it is not uncommon for them to give us a bad year in both or more regions? I'm puzzled why there is controversy between religion and science. Surely there is more to this universe than we understand, and likely may be capable of understanding. Stimulate a neuron and it fires more. There doesn't appear to be much cognition or awareness there; so, how do you tie a whole bunch of non-aware neurons together and end up with "I think; therefore, I am."? There are modern models of reality that require somewhere between 6 and 11 dimensions to work; I have some doubt that the human brain is capable of conceptualizing 11 orthogonal dimensions. Symbol manipulation - sure, even I can do that, but actually conceptualizing them all at the same time; I doubt it. Just a couple of illustrations that leave a lot of room for there to exist things we really don't understand, physical and metaphysical, and may even make the boundary a little fuzzy. When I was in 7th grade my science class grew bacteria in a petri dish. We watched as our colonies grew from tiny specs to flourishing, multi-colored conglomerates. But, then the population appeared to enter an unhealthy phase and eventually decay set in and a wasteland was created. I was saddened when my colony collapsed; either the microbes had made their environment toxic through their own waste or they had consumed all the available resources. I thought, if only they had regulated themselves, they could have sustained their glory days indefinitely. Then it occurred to me that biological organisms without thought are only regulated by predation. The end result of no regulation is always bloom and collapse. This was quickly followed by the recognition that humans have no predation; in remains to be seen if, as a species, we have more thought than a microbe. -
dcwarrior at 03:37 AM on 4 August 2010Why I care about climate change
#63 John Russell - I am sure you are right. Speculation - when global warming is discussed, what are the things that have to be done about it? 1. Your car is bad. People LOVE their cars. They wrap their identity in their cars. They like big cars that go fast. 2. The suburban lifestyle is bad. I.e., the very yardstick for measuring the American dream. The way we hope to advance in society, to show we are better than the Joneses - that's bad? 3. Consumption is bad. I.e., another yardstick of the American dream. There may be others. But we are telling people they have to give up that upon which they have built their hopes and dreams. AND, if they should take the scientists' advice, they'd fall behind. What if the scientists are then wrong? I can imagine how such an anxiety would make people vulnerable to someone stating emphatically that the scientists are wrong, there's nothing wrong with CO2 and all the worry is a product of deluded liberals who are out to get research money. -
chris at 03:31 AM on 4 August 2010Plant stomata show higher and more variable CO2 levels
David Middleton at 02:06 AM on 4 August 2010 Geocarb: The most up to date versions of Berner’s excellent model for long term carbon cycle processes [***] have a temporal resolution of 1 million years. Geocarb is a model. It isn’t a measure of [CO2] in the deep past, and it certainly can’t be used to assess [CO2] during the Neogene ice age cycles represented in Antarctic cores (see following paragraph). In any scientific analysis we use the appropriate tools. Geocarb, however nice a model, doesn’t give us insight into atmospheric [CO2] during the last 700,000-odd years where we have highish resolution direct measures of atmospheric [CO2] from ice cores. I wonder whether you have read the Geocarb papers? These show zero variation of [CO2] during the Neogene ice age cycles. If you look at the Geocarb papers you will see that the [CO2] levels in the deep past (Phanerozoic) are defined as “RCO2 is the ratio of the mass of atmospheric CO2 at a past time to that at present (weighted mean for the past million years”) (see e.g. legend to Figure 18 of the linked paper). David, if Geocarb sets the baseline for atmospheric [CO2] by averaging the last million years, how can we possibly use Geocarb to assess specific atmospheric [CO2] in ice cores?Your argument simply doesn’t make sense. Geocarb is a model for assessing our ability to constrain [CO2] levels in the deep past through our understanding of long term (multi-million year) carbon cycling. Please read the paper(s). Plant stomata: ”Plant stomata are a lot noisier than ice cores. One doesn't just throw out the high frequency data in signal processing just because it's noisy.” The problem is that the noise (+/- 30-60 ppm as indicated in the paper I linked to in my post you’re responding to) often overlaps with the difference between ice core [CO2] data and apparent stomatal [CO2] data. It’s not a question of “throw(ing) out high frequency data”. The question is whether the apparent differences between some (but not all) stomatal data and ice core data is statistically significant. I think we both agree that the ice core [CO2] data is temporally averaged due to the variably slow rates of firn sealing. However there isn’t any strong evidence that the ice core data is biased low as you insinuate. If the stomatal frequency boffins come at some point to a conclusion as to a reliable means of determining historic [CO2] with highish precision, then that will be great. In any case the high resolution Law Dome data is only temporally averaged on the decadal time scale. AIRS and polar [CO2]: We're quibbling (or you are I should say!) over a few ppm of [CO2]. You're happy to use a model for [CO2] in which [CO2] is averaged over the last 1 million years to attempt to counter the Antarctica ice core data, and yet you are fussing about a possible few ppm difference between Antarctic [CO2] and global [CO2]. I think your quibbling is misplaced. Atmospheric [CO2] has been measured in Antarctica (South Pole) since the early 1990's. We can compare the directly measured South Pole [CO2] with the [CO2] measured at Mauna Loa or from the globally averaged sea surface sites (or with globally and yearly averaged AIRS data). The difference is small (a few ppm). How science works: The idea that scientists set out to "debunk" something is silly. Scientists set out to find stuff out. With careful experiment and analysis the real world leads them towards reliable interpretations of natural phenomena. If this happens to lead to a robust conclusion that is at odds with other interpretations then that's just great. I can't imagine a real world example where your assertion "Science is all about skepticism and debunking (AKA testing)." might have any meaning! Science is surely about the formulation of hypotheses, testing these with experiments/analyses and seeing where the latter lead. [***] Berner RA (2006) GEOCARBSULF: A combined model for Phanerozoic atmospheric O-2 and CO2 Geochim. Cosmochim. Acta 705653-5664. -
gallopingcamel at 03:25 AM on 4 August 2010Grappling With Change: London and the River Thames
doug_bostrom, Thanks for a terrific account. It was of special interest to me as I used to work in Greenwich where the S.S. Mackay (a venerable cable ship) was moored. The roads inside our factory were far below high tide so the Mackay seemed to float above us. While I had nothing to with flood control on the Thames I worked hard to clean up the river so that fish could return. By 1979 I was raising rainbow trout in commercial quantities using Thames water. This was only possible because the water quality was steadily improving thanks to a collaboration between industry and volunteers coordinated by government (the Thames Water Authority). In Pepys' day, the Thames was a commercial salmon river but the water quality deteriorated as the city grew. The last Thames salmon was caught in 1815 but now the salmon are back, showing that even catastrophic levels of pollution can be reversed. Like Mexico City, much of London is sitting on hundreds of feet of mud. There is also an excellent aquifer and my company had a 500 gallon/minute well. After a little arm twisting by the TWA we stopped pumping. We were told that the depletion of the aquifer was causing London to sink. Is that effect measurable? -
John Russell at 03:13 AM on 4 August 2010Why I care about climate change
In spite of what the deniers would like the general public to think, concern for the effects of AGW seems not to be linked to religious, political, monetary or other influence or belief. I know sceptics, deniers and 'warmists' (ugly word -- but short) from the both the left and right, religious and otherwise. I'll accept that there is perhaps a tendency for environmentalists to be concerned about AGW, but that's hardly surprising is it? And anyway, what's to be despised about concern for the environment? I suggest that what divides the two sides is more likely to be something psychological; something perhaps related to fear. One of these days some scientist will work it out. In the meantime, John, keep up the good work. It's very much appreciated. -
OntheEdge at 03:03 AM on 4 August 2010Why I care about climate change
[first time user -apologies if this is a double post] just wanted to add my thanks for this well informed site which I've used in my battles with deniers within the community of believing Christians. Quoting the prophet Amos is so apt as he faced the same sort of denial of responsibility in his time as we see and hear today among right wing Christians. Believing themselves to be chosen and special while adopting alien ideologies which excused their lack of concern for the poor, Amos rightly tore into them no holds barred. -
RSVP at 02:14 AM on 4 August 2010Why I care about climate change
John, Your website (and motive) is commendable, and I am grateful to you. The cartoon above is perfect! Commenting... under Soviet domination, countries in Eastern Europe relied more on public transportaion and used horses for farming in great numbers before the fall of the Berlin Wall. They didnt realize that they were ahead of the times with their "backward" psuedo-ecological farming methods. The same may apply still in parts of India, etc., but things are changing fast, unfortunately... or?? Economic growth is tied to method, and method obviously makes a difference for global warming. For now, reducing poverty appears to be at odds with global warming. (Try to imagine getting emergency food supplies today in Africa without fossil fuels.) The problem is not simple, and regardless of whether global warming it is due to GHG emissions, waste heat, or something else, the expectations for sustained economic expansion remains and needs to be seriously addressed. (Greener, slower lifestyle issues might be a good future topic... or how much is too much???) And can this be discussed without getting political? -
Waste heat vs greenhouse warming
RSVP - In reference to my previous post, noting that if GHG's increase -> outgoing radiation decreases -> there is an energy imbalance -> the energy/temperature of the Earth/atmosphere will accumulate/increase until energy in = energy out.: The Empirical evidence topic, Figure 2, directly shows the effect of GHS's on the efficiency of the Earth radiating energy to space. This is the energy imbalance I referred to, and leads to energy accumulating until the temperature rises and the sum energy radiated out equals that coming in. -
David Middleton at 02:06 AM on 4 August 2010Plant stomata show higher and more variable CO2 levels
chris at 08:28 AM on 1 August, 2010David Middleton at 07:00 AM on 1 August, 2010 GeoCarb is a (very nice) model with 10 million year resolution. I don't see how you can use this to say that much about what true [CO2] levels were in the past at high resolution. It certainly doesn't "trump" direct measurements.
The Antarctic ice cores are not "direct measurements" of global atmospheric CO2. They are direct measurements of gas that filtered into snow and were eventually trapped in ice. They are an indication of what the atmospheric CO2 was in the air, near the ground over Antarctica.
GeoCarb is a very low frequency model-derived function. The resolution is low; but it is far better than 10 million years in the Neogene.
It shouldn't "trump" the ice cores. But it should be incorporated with the ice cores and the stomata data to a more complete "spectrum" of the CO2 "signal."
-
Waste heat vs greenhouse warming
RSVP - "Now you are basically saying that GHGs are removing waste heat. In other words, CO2 is helping to cool the atmosphere." I'm wondering if you are deliberately being obtuse? I'm really having trouble understanding your comments in any other context. "...it has to radiate both sources of energy into space." - If the Earth is in energy equilibrium (averaging over a period of time, it never is on an instantaneous level), it needs to radiate as much energy out to space as it receives from the sun, radioactive decay at the core, AHF, and whatever hot air is generated by climate discussions. Equilibrium means energy in = energy out. The amount of IR radiation emitted from the Earth and the atmosphere scales with the 4th power of temperature. So if there is an increase/decrease of energy going in -> the temperature will rise/fall until the radiation out equals that amount of energy. In addition, GHG's slow the radiation of energy from the Earth and atmosphere (the Earth becomes less efficient at radiating energy at any particular temperature), which means that if GHG's increase -> outgoing radiation decreases -> there is an energy imbalance -> the energy/temperature of the Earth/atmosphere will accumulate/increase until energy in = energy out. -
CBW at 02:00 AM on 4 August 2010Why I care about climate change
John, Probably unnecessary, but I'll add my thanks for your efforts on this site. You're doing important work, and making a difference in the world. I hope your daughter comes to admire that and learns from the example you set.
Plant stomata frequency estimates of past [CO2] have large uncertainties (e.g. +/- 30-60 ppm; see a recent analysis of reconstruction uncertainties in Betula nana leaves). I think these studies are fine, and useful for estimating broad atmospheric [CO2] levels (or changes in [CO2] levels) in the deeper past, but one should accept that these are not precise measures.Plant stomata are a lot noisier than ice cores. One doesn't just throw out the high frequency data in signal processing just because it's noisy.
The NASA AIRS comparison is misleading since these are generally shown as snapshots. If one averages a full years worth of AIRS data, then the yearly averaged difference between polar and equatorial (say) [CO2] is only a few ppm. It's not reasonable to compare AIRS snapshots with ice core data (or stomatal data for that matter!) which is significantly temporally averaged.Then maybe you can show me an AIRS image that shows the polar regions to have higher CO2 levels than the mid and low latitudes. If it all averages out over the year, the polar regions would have to have higher CO2 levels at some point during the year. Every daily AIRS image I've seen, shows the polar regions to have 15-20 ppmv less CO2 than the mid and low latitudes. Getting the monthly average differential down to 5-10 ppmv and the annual average differential down to a few ppmv is a neat trick, considering how sparsely sampled the polar regions are.
![](http://www.nasa.gov/images/content/411797main_slide9-AIRS-full.jpg)
Obviously the mechanism for sealing off atmospheric samples in ice cap or glacial firn results in a considerable multiyear averaging of the atmospheric [CO2]. In the high resolution Law Dome core the averaging is smallish, whereas in the deep Antarctic cores the averaging may encompass a large number of years (can't remember off hand, but this may be a hundred years or more???).It can vary from a few decades to more than two thousand years.
However considering the high resolution Law Dome data and the last couple of thousand years, I don't see any basis for concluding that the ice core data is biased low as you suggest. Yes, it's smoothed (it's something like a 10 year running mean); but (just like contemporary [CO2] variation), we expect rather low amplitude variability in [CO2] at high resolution. Yes, the natural variability (likely largely ENSO-related, with perhaps some significant wildfire variability) encompassing a few ppm will have been smoothed out. But it's not reasonable to think that we are missing large jumps and falls in [CO2], apart from anything else, because largish non-ENSO-related increased [CO2] levels take a long time to drop, and so they should stil be observed in cores. In any case if we're not seeing them (i.e. high resolution, large amplitude jumps and falls in [CO2]) during the last 50 years of very high resolution measurement, what is the basis for expecting that these occurred in the past?We don't see those jumps in the plant stomata data either over the last 50 years. The stomatal response is consistent with a steady increase in atmospheric CO2 over the last 60 years... ]
![](http://www.amjbot.org/content/vol92/issue4/images/medium/abot-92-04-18-f04.gif)
Incidentally, I don't understand the reference to "skeptics" in your last paragraph. These guys/gals are just scientists working to improve their methodologies and obtain insight into the past. I don't think one should adopt the false notion that science is composed of groups of people that have one view of the science and others that are "skeptics".The first post in this thread says:
The skeptic argument... Plant stomata show higher and more variable CO2 levelsThat's actually what the science says. Hence, my reference to "skeptics."
If the group of people you refer to were "trying to debunk AGW" they would be wasting their careers. Science simply doesn't work like that...Actually, that is exactly how science works. To quote Einstein, "No amount of experimentation can ever prove me right; a single experiment can prove me wrong." Science is all about skepticism and debunking (AKA testing).
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