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Comments 125301 to 125350:

125301. From Peru at 08:20 AM on 19 January 2010
        Two attempts to blame global warming on volcanoes
        Geothermal Heat emission = 0.09 watts/m^2 ? This is 10% of our measured Radiative energy imbalance of 0.9 watts/m^2! Where do you get this data? 10% seems too much!
125302. Tom Dayton at 08:09 AM on 19 January 2010
        Two attempts to blame global warming on volcanoes
        Paz, the heat coming from undersea volcanoes along with the entire rest of the crust of the Earth (0.09 watts/m^2), is tiny compared to the forcing from CO2 (2.66 watts/m^2). For details, see my comments #234 and the following #235 in the Skeptic Argument Volcanoes emit more CO2 than humans.
125303. From Peru at 07:48 AM on 19 January 2010
        Two attempts to blame global warming on volcanoes
        This is a thing that continues to cause me a headache: The Early 20th Century(1900s-1940s) Warming of 0,4 ºC. It seems to me a lot strange that it peaked in the 1940s (then followed by a slight cooling of -0,1ºC until the 1970s) when both: a)Solar Activity peaked in the 1960s b)Big volcanos erupted(after near 50 years of calm) in the 1960s So, why Temperatures peaked in the 1940s and not in the 1960s? My suspect were Tropospheric, man-made AEROSOLS, but after seeing the GISS graph, TOTAL forcing still peaked in the 1950s at 0,5 W/m^2, still A DECADE(1950s) AFTER TEMPERATURES BEGAN TO COOL! What is going on? It could be: 1)Errors in temperature data or in the GISS total forcing estimation(this second is more likely as Aerosols Forcings are still considered "highly uncertain") 2)Climate Variability masking the (warming)forcing in the 1950s (for example, a series of weak El Niños and strong La Niñas) What do you think?
125304. Paz at 07:35 AM on 19 January 2010
        Two attempts to blame global warming on volcanoes
        Is there any data on underwater volcano eruptions? An argument that seems to be popping up more and more is that global warming is driven by underwater volcanoes that (1) warm the oceans, which (2) in turn warm the athmosphere. Is there any data about whether this can be ruled out? I think the appeal of this argument comes from a) that underwater are supposedly hard to track (so a large scale increase of eruptions could be going on without our knowledge) b) several recent papers arguing that part of the recent warming is driven by the oceans. It did some searching and could not find anything on this hypothesis, although I am sure it must be out there.
125305. yocta at 07:02 AM on 19 January 2010
        Why does CO2 lag temperature?
        oops I meant CO2 in this case not lagging temperature :$
125306. Andy Skuce at 06:42 AM on 19 January 2010
        Two attempts to blame global warming on volcanoes
        Klaus, you may find this article helpful: http://climate.envsci.rutgers.edu/pdf/ROG2000.pdf On page 192 there's the following statement: "While the Mount St. Helens eruption of 1980 was very explosive, it did not inject much sulfur into the stratosphere." There's also a table on the same page comparing historic eruptions and the various indices used to measure the intensity of the eruptions and their effect on climate.
125307. chris at 04:11 AM on 19 January 2010
        Two attempts to blame global warming on volcanoes
        Klaus, the site urled just below has a list of all of the major known volcanic eruptions of the Holocene (having Volcanic Explosive Index of 4 and higher). If you click on each volcano in the list it gives you detiled information about known properties. You might get some info there as to why St Helens isn't on the graph. It was a pretty major explosion, but perhaps it didn't have a large effect on very high altitude transmission of solar radiation..??? http://www.volcano.si.edu/world/largeeruptions.cfm?sortorder=desc 70n, a very quick way of assessing the Mauna Loa record is to compare it with the record of CO2 averaged over the sea surface sites. The data are continuously updated at the NOAA Mauna Loa site. The Mauna Loa record is very similar to the record of the sea surface average: http://www.esrl.noaa.gov/gmd/ccgg/trends/
125308. Klaus Flemløse at 03:49 AM on 19 January 2010
        Two attempts to blame global warming on volcanoes
        I am very facinated by the Mount St. Helens explotions in 1980. To me it was big.However is not at the graphics. Is it as mistake ? Do you have a listing of vulcanoes by size ? http://en.wikipedia.org/wiki/Mount_St._Helens
125309. 70rn at 03:06 AM on 19 January 2010
        Two attempts to blame global warming on volcanoes
        Yeh? Well it's nice to have that off the list of arguments. All we have to do now is minutely scan every centimetre of the sea floor for volcanoes, (who are there in their millions apparently, pumping away in vast numbers with out changing the temperature profile or acidity of the ocean significantly, which is thoughtful) and you might even cause some ambivalence on this issue in a few heads.
125310. Ned at 02:51 AM on 19 January 2010
        Two attempts to blame global warming on volcanoes
        Thanks, 70rn. It's even simpler to point at all the other CO2 monitoring stations that have been set up elsewhere: http://gaw.kishou.go.jp/wdcgg/ Just as an example, I clicked on "Data / Quick Plot", then "Barrow" (Alaska), then "CO2 (continuous)", then chose Monthly data "File / Quick Plot", and plotted the result as a PNG. Lo and behold, a nice rising trend in CO2 from 1973 onward, with a strong seasonal cycle, too. I don't know of any volcanoes at Point Barrow, and I am unaware of any volcanoes that belch CO2 with such a nice, smooth, consistently rising trend over three decades!
125311. 70rn at 02:01 AM on 19 January 2010
        Two attempts to blame global warming on volcanoes
        Here's a paper discussing the detection and removal of local co2 emissions from the Mauna Loa ('mount' obviously, but get better search results when you that term) record. Basically it states that localized co2 from the vents is at a completely different concentration and not mixed with the surrounding air and as such easy to distinguish from the background. It also notes that it is variable minute by minute - were as background data is steady over hours.
125312. 70rn at 01:39 AM on 19 January 2010
        Two attempts to blame global warming on volcanoes
        @ Ned Yeh the Mount Loa comment is pretty hard to shake off. A point to highlight to those that make this claim is the lack of a spike in the data last time it erupted (84) and the fact that the volcanoe has been overall less active than normal over the following quarter of a century, and as such if the readings were contaminated by the site then the data should have shown a corresponding decline. I don't doubt that the current data is calibrated against other sites in the NOAA network as well as secondary observations from sources like weather balloons.
125313. Ned at 00:22 AM on 19 January 2010
        Two attempts to blame global warming on volcanoes
        Very well done, John. There are additional variants on this too, like the claim that submarine volcanoes in the Arctic Ocean are responsible for the decline in sea ice (you can see this from time to time on WUWT), or the claim that because the oldest CO2 measurement station is on the side of Mauna Loa, CO2 isn't actually increasing at all, it's just local contamination. Anyway, lacking your patience I usually see claims that "volcanoes are the real cause of AGW!" as evidence that the person making the claim doesn't have enough common sense to justify my participation in a serious discussion. But it's good to see that not everyone shares my impatience. This site is fantastic, and I've recently taken to directing people over here whenever I run across another version of the standard "un-skeptical skeptic" talking points.
125314. Ned at 23:23 PM on 18 January 2010
        2009 - 2nd hottest year on record while sun is coolest in a century
        Trog writes: "[...] I tend to trust [UAH] more than GISS since it is satellite data and not subject to as much manipulation. UAH shows a declining trend more in line with the sun." There are at least four satellite-derived temperature analyses (from RSS, UAH, and two from UW). Their current temperature trends are as follows (in K/decade): RSS: +0.15 UAH: +0.13 UW-RSS: +0.15 UW-UAH: +0.11 All four of these show positive trends during a time when the sun has been cooling. (They're also not all that far from the GISS trend, which is +0.16 K/decade over the same period) In other words, the relatively small effect of the solar cycle on global climate is only partially reducing the impact of CO2 driven warming. And of course once the sun starts to warm again, it will be exacerbating the problem (slightly) rather than helping mask it as it does now (slightly).
125315. From Peru at 17:17 PM on 18 January 2010
        Skeptical Science now an iPhone app
        Oopps. The graphs were not pasted. How can I post graphs, or any kind of figure? In the graphs, my numbers were: Total Forcing (1950s): 0,5 W/m^2 Solar Forcing (1950s): 0,2 W/m^2 Residual (1950s): 0,3 W/m^2 This is aerosol + Greenhouse gases + Land use change. The analysis forcing-by-forcing for tomorrow. Stay tuned.(please help with the graphics)
125316. From Peru at 17:07 PM on 18 January 2010
        Skeptical Science now an iPhone app
        Well, this is my previous comment, in graphical mode: First the Various Forcings from NASA GISS, showed the solar forcing: Then the TOTAL FORCINGS: So 0,3 W/m^2 were NOT from the Sun. They were from Aerosol + GHG. (note:all numbers approximated from reading the graph)
125317. yocta at 16:39 PM on 18 January 2010
        Why does CO2 lag temperature?
        RE# 39 thingadonta I don't think it's a preoccupation at all, it is the strongest link as to why there is a temperature anomaly over the last 50 years. And to keep making sure of this, more and more measurements and analysis are performed to verify it.(And lets not forget methane) It's fantastic that scientists can recreate past climates and find the causes as to why there was sudden shifts in atmosphere composition or biodiversity to major geological events, Earth's precession or even meteorites. Examples like the closing of the Isthmus of Panama are on the millions of years (geological) time scale. On the much much shorter climate age time scale, things like the general circulation or the pattern of the ocean conveyor belt are relatively stable compared to the geological events you have mentioned. In the context of climate ages, with CO2 being very strongly infrared active, , the sudden recent spike in CO2 ppm in the atmosphere, the sudden recent spike in globally averaged temperatures, empirical data showing CO2's effect on radiative forcing, (and temperature in this case not lagging CO2)it is impossible to overlook the villain.
125318. Doug Bostrom at 16:31 PM on 18 January 2010
        2009 - 2nd hottest year on record while sun is coolest in a century
        "...we've just established that the sun has been cooling over the last 35 years while global temperatures have been rising." Well, the radiometer measurements must have been manipulated. Or the sun must have been manipulated. Whatever. Will The Team stop at nothing in their quest to establish a global Marxist wealth redistribution machine?
125319. From Peru at 16:03 PM on 18 January 2010
        Skeptical Science now an iPhone app
        John Cook: Thank you (and Hansen, obviously) for the graph! To you and to readers: What forcing do you think(personally) could explain better the Early 20th Century (1910s-1040s) Warming? a)The Sun b)Aerosols (Black Carbon + Sulfate)
125320. Trog at 14:46 PM on 18 January 2010
        2009 - 2nd hottest year on record while sun is coolest in a century
        As Algore said, "It's complicated". UAH has a very different ranking of hottest years, which I tend to trust more than GISS since it is satellite data and not subject to as much manipulation. UAH shows a declining trend more in line with the sun. In any event, sun activity matches temperature better than CO2 concentration. Now, if you can model sun, humidity, high and low clouds, ice and snow, ocean currents, CO2, wobble, solar flares and cosmic rays all operating in a chaotic relationship with unknown interactions and lags, you might be making some progress. I don't think we're there yet. I'll stick with observations and not trust models for now.
        Response: That the UAH satellite data is pristine, untouched data seems to be a common misconception. On the contrary, satellite data is subject to a great deal of manipulation. Orbit decay causes the altitude of the satellite to drop so that needs to be filtered out. The temperature of the actual satellite also changes and this affects the readings. Data from different satellites need to be spliced together. Cooling in the stratosphere needs to be filtered from the warming in the troposphere. And probably the most complicated adjustment is accounting for diurnal drift - the time of the day that the satellite passes over the equator slowly drifts over time (exacerbated by orbital decay). In fact, diurnal drift is the greatest source of discrepancy between the UAH data and RSS data.
        
        And I must say, I find it extraordinary to hear you say "sun activity matches temperature better than CO2 concentration" when we've just established that the sun has been cooling over the last 35 years while global temperatures have been rising.
125321. Marcus at 13:45 PM on 18 January 2010
        Tree-rings diverge from temperature after 1960
        I'm guessing that acid rain had a *lot* to do with the sudden decline in tree-ring width post-1960. It certainly doesn't prove any kind of global cooling post 1950. It does, however, highlight the need to use more than a single proxy for determining climate in the absence of direct temperature measurements
125322. From Peru at 13:25 PM on 18 January 2010
        Skeptical Science now an iPhone app
        John Cook: In the comment to the previous post, I said: "The Early XX Century Warming(+0,5ºC) peaked at about the same time than WWII(around 1940), then a slight cooling of about -0,1ºC followed until about 10 years when temperatures stayed nearly constant between 1955 and 1975. The Sun Activity instead continued to incrase until mid-1950s, when it began a slow decline. Remarcable is that temperatures peaked BEFORE Solar Activity (a whole solar 11-year cycle indeed!). This seem inconsistent with the hypothesis that the Sun is the main responsible of the Early 20th Century warming." Then I talked about the Aerosol Forcing hypothesis(sulfates,black carbon...), and concluded with the question: "Has anyone compared the Sulfate vs. Black Carbon emissions making timeseries-graphs like the one presented here? (I referred to the TSI vs. GISS Temperatures in the previous post) That will do a good to determine which forcing (Solar or Aerosols) had the greatest impact." John Cook, I am still waiting for your response.
        Response: The estimated radiative forcing from sulfates and black carbon are available for download from the NASA GISS website. Please feel free to make a time series graph (and if you do, let us know what you find).
        
        
125323. Riccardo at 11:44 AM on 18 January 2010
        Skeptical Science now an iPhone app
        This exercise has not been solved for many decades. I don't think is going to be solved any time soon even by solar physicists, let alone we readers :)
125324. blouis79 at 08:53 AM on 18 January 2010
        Scientists can't even predict weather
        The wave/tide analogy is a good one. Both are cyclic. Long term climate is also cyclic, not linear. The formula to convert radiative flux (RF) to surface temperature change is (ΔTs): ΔTs = λRF, where λ is the climate sensitivity parameter. This assumes ALL GHG forcing factors are equivalent despite that clouds produce negative feedback. Models that use a linear equation can only produce linear predictions based on recent trends. Even IPCC scientists say that GCMSs should be exercised on weather. http://environmentalresearchweb.org/cws/article/opinion/35820 The global energy budget (Kiehl/Trenberth) features high in the computations but the net positive radiative forcing is derived from Hansen's computer model. "GH theory (IPCC: Myhre et al.) tells us that the CO2 climate forcing from this increase equals 5.35 times the ln(ratio) = 0.035 W/m^2 Even if we escalate this by a factor of 3.2 to account for net positive feedbacks, as estimated by the IPCC model simulations, we arrive at 0.112 W/m^2 How do K+T arrive at 0.9 W/m^2 or eight times this value?" See http://chriscolose.wordpress.com/2008/12/10/an-update-to-kiehl-and-trenberth-1997/#comment-1493
125325. From Peru at 07:51 AM on 18 January 2010
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        Is there any connection between Solar Cycle LENGHT and Total Solar IRRADIANCE? If yes, what is the link between them?
        Response: When the sun is showing a long term warming trend, the solar cycle tends to get faster. Conversely, when the sun is cooling, the solar cycle slows. This is why the solar cycle 24 is taking so long to get started at the moment - because the sun is cooling at the moment. Why this is so, I leave as an exercise for the reader :-)
125326. Tom Dayton at 06:21 AM on 18 January 2010
        Temp record is unreliable
        Gavin Schmidt has a brief response to the Smith & Coleman bizarre claims that the "real" temperature stations' data have been replaced by averages of unrepresentative stations' data, and that data have been destroyed. Gavin's response is to Leanan's comment #9 on 17 January 2010 in the comments on the RealClimate post 2009 Temperatures by Jim Hansen.
125327. Tom Dayton at 06:15 AM on 18 January 2010
        Skeptical Science now an iPhone app
        RealClimate has a new post titled 2009 temperatures by Jim Hansen, subtitled "If It's That Warm, How Come It's So Damned Cold?"
125328. Tom Dayton at 06:11 AM on 18 January 2010
        Skeptical Science now an iPhone app
        greenman3610 has a new video on the recent cold weather and its difference from climate.
        Response: I've added this to the skeptic argument "December 2009 saw record cold spells in Eurasia and USA".
125329. Riccardo at 22:56 PM on 17 January 2010
        Skeptical Science now an iPhone app
        Berényi Péter, "Anyone, who cares for climate models should welcome an opportunity to verify them against independent data sources." This time i fully agree with you. I'm not the only one, many scientists around the world are still working on this issue; they try to improve new measurements and to correct and homogenize old data. You will easily find a lot of papers on the dry bias and possible recalibration of radiosonde data. No one will throw those data away for sure. I'm not going to call a reality check surfacestation.org for two main reasons. First, the very idea of that site is that scientists are not aware of the urban heat island effect and the site change/alteration issues. It's not true; indeed, as people behind surfacestation well knows, there are a lot of ongoing adjustments of the raw data (which, though, they don't like). Second, in a unusual consideration of non-scientific issues, the NOAA analysed the data of just the "good" stations and found almost no difference. The whole story turned out to be a strong and surely independent confirmation of the quality of their dataset and analysis. I'm just sorry for the hundreds of people sent around the US taking pictures following a false hope.
125330. Donald at 21:55 PM on 17 January 2010
        Skeptical Science now an iPhone app
        The models presumably include the solar forcing in W/m^2 from the TSI reconstruction- solar cycle length is just a proxy. Average TSI peaks in about 1960. Although there is yearly variation, there is not the same delayed correlation with the 1940's temperature peak, so the question of lag in the models doesn't seem to be relevant. http://www.skepticalscience.com/solar-activity-sunspots-global-warming.htm
125331. Qwerty at 21:48 PM on 17 January 2010
        It's cooling
        Does this data only go back to 1950?
125332. RSVP at 20:53 PM on 17 January 2010
        Skeptical Science now an iPhone app
        Actually, they do, but only for effects of CO2.
125333. RSVP at 20:52 PM on 17 January 2010
        Skeptical Science now an iPhone app
        Donald Exactly. This article brought to mind the same question. That is, whether climate scientists include hysteresis in their models.
125334. Donald at 20:37 PM on 17 January 2010
        Skeptical Science now an iPhone app
        It's interesting to note a peak in the solar cycle graph (a solar cycle minimum length) about a decade before the peak in temperatures around 1940. Is there any connection? The 1940 temperature peak (which from reading this site I seem to remember is not well explained by known forcings or the models) is sometimes ascribed to an artefact of changes in the method of temperature measurement in the 40's. The minimum solar cycle length in the 30's doesn't show up in the TSI reconstruction as a peak. Is the slightly delayed correlation just coincidence?
125335. folke_kelm at 20:20 PM on 17 January 2010
        A visual deconstruction of a skeptic argument
        There is much confusion about, why we are emitting more and more CO2 and yet always constantly 55% is absorbed. Then there is increasing CO2 in the air when temperature rises. But we see, ocean is absorbing despite increasing temperatures. How does this fit? If you have rather basic knowledge in physics and chemistry it is really easy to stitch these phenomenons together and understand, how the system works. let me explain. First, take, that the amount of carbon dioxide in the system Atmosphere+ocean+biosphere is constant. If that is so, the certain amounts of CO2 in the different subsystems is largely dependent on temperature. If it warms, more CO2 will move into atmosphere, if it cool, more into the ocean. This follows Henrys law. second, if you add CO2 into only one subsystem, the atmosphere, you disturb the equilibrium, with the result, that a constant amount of CO2 will leave the atmosphere and move into the other two subsystems, until equilibrium is reached again. Where the point of equilibrium is, is still dependend on temperature. So, if temps are rising, we will see a slightly decrease of the absorbed fraction of CO2. We are speaking here entirely of the biological carbon cycle. There is a geological too, which removes carbon out of all three subsystems, but here we talk about processes which take several 100 000 of years. I hope this makes it clear for some people how this works
125336. Marcus at 15:12 PM on 17 January 2010
        Skeptical Science now an iPhone app
        I do also love how those that are so quick to denigrate surface-based temperature measurements (because they don't say what they'd like them to say) are so quick to elevate radiosonde to almost exalted status-even though the same "issues" might apply. The difference is that, whilst ground-based & satellite based temperature readings are in close agreement, the radiosonde & satellite based measurements of humidity are *not* in agreement-at least as far as I can tell. Berényi Péter willingness to accept a single paper, based on what could be dubious data, says a great deal about his own political bias, IMHO.
125337. Berényi Péter at 14:13 PM on 17 January 2010
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        guys, it is indeed possible that sixty years of radiosonde data are crap. Even the air can go into one corner of the room any time leaving me in vacuum. It is possible, even if unlikely. I could compute its probability. Considering the immediate usefulness of moisture data, it is also unlikely that radiosondes measured naught. It almost falls into the "if I had three legs it would not pass unnoticed" category. It is even more unlikely that the undetected systematic error has a consistent downward trend over such a long timespan. However, all is not lost. If in doubt one can go back, build a replica of each moisture sensor used (goldbeater's skin, rolled hair, carbon hygristor or capacitive sensors), go to the lab and test their relative humidity response, temperature dependent time lag and all the other relevant features. The old instruments can even be tested in situ for any unkonw source of bias like UV radiation, aerosols or whatever. It is a calibration job that does not even require a climate scientist. In fact there are better educated folks to do such a job. I understand that some of the recalibration is already done in the NCEP dataset (i.e. correction for decreasing response time), but the downward trend still remains. Believe me, the old folks were neither fools nor lazy bastards. If they used an instrument, it did measure what it was supposed to. They checked it and re-checked it. There might be some caveats, but it is all documented, meticulously. A serious re-evaluation of upper troposphere radiosonde humidity measurements should be the highest priority job right now, just as Paltridge et al suggest. This dataset does not depend on any atmospheric model, the corrections, if any, should come from entirely different souces. The same can not be said about satellite measurements of upper troposphere moisture. The incoming radiation is a complex function of vieving angle and pressure, temperature and relative humidity values along an entire (possibly oblique) column of air. The inverse transformation is impossible without some model of the supposed vertical and horizontal distribution of these parameters. Moreover, clouds make it next to impossible to do the calculations. At the same time most of the weather is about clouds (Is it sunny? rainy?). I do not think the downward trend can be calibrated away as apparently Paltrige does not believe it either. He just dares not make this statement directly. Otherwise he would be accused of a "clear and explicit political bias". I can tolerate it for I'm not running for grant money, his case might be different.
125338. Marcus at 13:13 PM on 17 January 2010
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        I've seen at least one paper which suggests that the correlation between solar activity & the global temperature anomaly has been low (approx. 35%) since 1950, with a further drop in correlation (approx. 22%) for the period of 1980-2000). Yet for the period of 1900-1950, the correlation between solar activity & the global temperature anomaly was a whopping 75%! For a correlation to drop so much, in such a relatively short space of time, would require some kind of very rapid change in some other component of global climate-any guesses which one (btw, the correlation between CO2 & the global temperature anomaly, for the period after 1950, is around 78%. In the absence of direct measurements, pre-1950, it's hard to do a good correlation for the period of 1900-1950. However, given the almost static CO2 levels in the ice cores which cover that period, I'd suggest the correlation would have been close to *zero*. Again, such a massive change in correlation in such a short space of time!)
125339. Marcus at 12:43 PM on 17 January 2010
        2009 - 2nd hottest year on record while sun is coolest in a century
        Hope you don't mind me clarifying this, Chris (#28), but I've always been a little uncertain about the relationship between solar activity & CRF. As I understand it, increasing CRF leads to increased cloud formation which-in turn-leads to increased albedo & hence reduced temperatures-is that right? I also understand that decreasing solar output is strongly correlated to increasing CRF, because the suns output in some way deflects CRF's-again, am I correct in this? So what we're basically looking at here is a negative feedback loop-where reduced solar output directly reduces global temperatures whilst at the same time indirectly resulting in more cloud cover-which should also result in lower overall temperatures. If so, then I'd tend to think that CO2 must have an incredibly strong forcing to overcome such a *double whammy* (which is the scientific term for it ;) ).
125340. Marcus at 12:32 PM on 17 January 2010
        2009 - 2nd hottest year on record while sun is coolest in a century
        You know, this is why I love this site-because, as a scientist, most of the contributors here are able to direct us to Papers or other sources of information to back up the claims being made. At least here the likes of John P & nofreewind are simply an aberration in what is otherwise a hard-science web-site!
125341. ewe2 at 12:24 PM on 17 January 2010
        1998 DIY Statistics
        A similar demonstration of the issue is from an Australian political skeptic here. I almost understand statistics after that :)
125342. Riccardo at 11:46 AM on 17 January 2010
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        Berényi Péter, "the data ARE definitive. Paltridge at al. may use a cautious language (otherwise they would risk rejection due to politically motivated peer review)." Don't talk about truth when there's such a clear and explicit political bias. This presupposition undermines what you say next. Why should i take your words and not those of the authors themselves? You do not give any reason at all to go beyond the warnig given in the abstract. Satellite data have issues, radiosonde too; research is going on. Scientists try to overcome the difficulties with more data and more analysis and this is science. Paltridge et al. did science, you did not, not a single tiny reason why one should not be cautious with radiosonde data. And that's why you are left with a declaration of belief like "the data ARE definitive".
125343. Doug Bostrom at 11:39 AM on 17 January 2010
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        Berényi Péter at 09:26 AM on 17 January, 2010 Thanks for your point-by-point response. The CO2 mixing problem you refer to indicates a inhomogeneity of C02 that is trivial compared to the gross amount of anthropogenic addition. I'm sure you realize that. In fact, given your lack of confidence in satellite observations, I'm surprised you do not dismiss it. However, you fail to address the central challenge for doubters, also my original point, which is that you need to replicate (for instance) your examination and critique of satellite data versus radiosonde data for a plethora of observations in other fields in order to dismiss what appears to be a coherent composite signal providing a good fit with anticipated changes driven by AGW. This is going to be a major challenge. Again, using your present example, you've found a single paper that you believe invalidates satellite measurements of atmospheric constituents. Many other findings are in contradiction to this paper. A compelling argument against so many other results is going to require a much more robust body of evidence. If that should be the outcome in this case, you're going to need to do the same thing in a number of other arenas. For example, what about Antarctic ice loss as measured by the GRACE instrumentation? You'll need to develop a coherent explanation for how that might be in error. You could work that from a PGR angle, somebody ought to better resolve that issue, but as it stands now GRACE measurements of Antarctic mass are another result that at present appears to validate predictions arising from models of AGW. Again, multiple investigators have found the same general result from GRACE data. There are numerous other examples, I'm sure you realize that.
125344. chris at 11:27 AM on 17 January 2010
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        Not really Berenyi Peter! a. One can hardly assert that the Partridge results are "definitive", when the authors themselves state that they are not:

        "It is of course possible that the observed humidity trends from the NCEP data are simply the result of problems with the instrumentation and operation of the global radiosonde network from which the data are derived."

        b. Your appraisal of Soden et al (2005) isn't correct. Soden et al use the High Resolution Radiometer Sounder (HIRS) to measure upper tropospheric radiance in the 6.3 micrometre water vapour band. So they are measuring water vapour, if indirectly, just like any spectroscopic measurement. They use two methods to determine their "signature" of upper tropospheric moistening. (i) Their detector (T12) is sensitive to changes in relative humidity. Since they don't detect a change over the period (1979-2004) they conclude that the relative humidity hasn't changed. Since the upper troposphere has unequivocably warmed during this period, the absolute humidity must have risen. (ii) Soden et al also obtained a signature of upper tropospheric moistening by comparison of the MSU T2 and the HIRS T12 radiances. The emission level for T12 increases with increased water vapour; that of MSU T2 is sensitive to changes in oxygen (which doesn't change significantly in a warming, moistening atmosphere). Thus in a moistening atmosphere the brightness difference (T2-T12) should increase with time. That's observed. These qualititive signatures of upper tropospheric moistening were quantitated by comparison with models. But the signatures of upper tropospheric moistening were spectroscopic measures atmospheric water vapour (in the manner that one generally uses spectroscopy to measure molecular composition/concentrations etc.). And these "early" observations have been reinforced by the subsequent work describing increased tropospheric humidity in a warming world I cited (and Riccardo linked to). c. Atmospheric CO2 mixing. Not sure what significance you ascribe to that. On annually-averaged timescales atmospheric CO2 is well mixed to the extent that it makes no real difference to radiative forcing. For example one could compare the ARIS picture you linked to, to the Mauna Loa data (or ocean surface averaged CO2 data) here: http://www.esrl.noaa.gov/gmd/ccgg/trends/ ...and find that at Mauna Loa the July 2003 CO2 concentration was 376 ppm (pretty much as in the picture you linked to); the sea surface averaged CO2 level was around 374-5 ppm and so on. We all know that the production of CO2 from plants and humankind has regional origins and this is bound to be represented as small variations in distribution in temporal "snapshots". So we don't expect to see instantaneously mixed CO2. But yearly averaged CO2 concentrations are pretty similar wherever these are sampled around the globe...
125345. thingadonta at 11:25 AM on 17 January 2010
        Why does CO2 lag temperature?
        #38 Chris I like someone like yourself who at least keeps to the science. When I was at university, these were the things we were taught back in the 1980s-1990s. I am not nearly as familiiar with more recent papers as I am not an active researcher, maybe I could drag up some papers from my uni days. "the evidence increasingly supports slow reductions in atmospheric CO2 concentrations as the major driver of reduced temperatures that forced the onset of glaciations. This applies both to the Arctic glaciations of the late Pliocene [**], [***] (see above), [****],[*****] and also the onset of Antarctic glaciations 33-34 MYA [******]:" I am not a fan of this statement at all. C02 lags and follows temperature changes (e Vostok ice core) it does not intitiate them. It seems to me to be the recent scientific fad to attribute everything to magical C02. C02 also lags changes in oceanic circulation because these drag down temperature which then drags down c02 due to increased solubulity with cooler water, whether on decadal, millenial or million year timescales. The reverse largely occurs with increased oceanic circulation. This is why c02 follows T change in earth history (and also continental configurations eg Permo Carbonifeous glaciation, etc), but it does not cause it. The earth cooled around 33-34 MYA (Ive read elsewhere is was 37Ma) largely because of slow ocean circulation changes eg: 1. -the gradual closing of the Tethys Sea between Africa and Asia, which is still going on today with the gradual closure of the Mediterranean-the Tethys sea remnant-which will dry up completely in the next few million years- cooling things further as Africa and Asia completely join-which incidentally might initiate cause widespread glaciation similar to the Permo carboniferous, and also this gradual closing has cooled Africa from several mllion years ago leading to more Savannah, and the evolution of a upright ape on the plains-us-but that is another story. 2-The gradual increase in the Southern Ocean beneath Australia creating a strong polar belt which does not transport heat northwards.(I think the southern tip of South America also has somehting to do with this). The Isthmus of Panama closing and dragging down earth temperature was common knowledge when I studied at uni, I dont know where this common knowledge has gone since then. Scientific preoccupation with c02? re#37 The oceans do not 'add thermal energy to the planet', they simply distribte it differently depending on plate tectonic configurations and sea levels, which can change markedly over short geological time due to eg closure at the continental scale eg Isthus of Panama, joining of Arabian Peninsula and Africa etc, break up and formation of ice caps etc.
125346. Berényi Péter at 10:39 AM on 17 January 2010
        Skeptical Science now an iPhone app
        chris at 07:28 AM on 17 January, 2010: Let's have a closer look at the logic of e.g. Soden at al 2005. "Here we use climate model simulations and satellite measurements to demonstrate the presence of a distinct radiative signature of upper troposphere moistening on interannual to decadal time scales" They use both climate model simulations and satellite measurements. So far so good. If satellite measurements do show increased upper troposphere specific humidity and the model predicts the same, then it survived, it is not falsified by this particular measurement. "The observed moistening is consistent with model simulations and correspond approximately to a constant relative humidity increase in upper tropospheric moisture" This is already slightly off the mark. There is NO observed moistening so far. How could it be consistent with anything? "We further demonstrate that without such an increase, the model would be unable to reproduce the satellite-observed radiance record" That's it. There must be an increase, for without it, the model would be unable to reproduce observation. Observation of what? Radiance. Mark me. Not upper troposphere specific humidity, but satellite observed radiance record. Suppose for a moment, just for the sake of argument, that the model is crap. In this case if it is unable to do something it does not demonstrate anything aside from the fact it was crap in the first place. If it has no relation to the real world, it is not surprising that it could not reproduce real world measurements. On the other hand, if we go with model prediction and allow it to increase upper troposhere moisture as it was programmed to do anyway and by this it mimics the satellite observed radiance record, it only means that we have found a rather complicated and expensive way to fit curves. Let's put it another way. If radiance is measured and there is no other way to derive specific humidity values form these measurements than through the model to be verified, then the specific humidity trend produced this way can not be used to verify the model. The two things are not independent. Suppose someone constructed a model with no upper troposphere specific humidity increase which could reproduce the same radiation signature. Would it prove anything about specific humidity trends in the upper troposphere? No. It would only demonstrate that Soden's logic is flawed, what we know anyway. Circular logic is wrong, because it is circular.
125347. chris at 10:19 AM on 17 January 2010
        2009 - 2nd hottest year on record while sun is coolest in a century
        re NewYorkJ and top article: Exactly so - we could make a rough quantitative analysis of the cooling contributions that are currently opposing enhanced greenhouse-induced warming: (i) solar cycle max-min give a lagged ~0.1 oC [*]. With an abnormally-prolonged minimum and a small decrease in solar output it seems reasonable that this is currently suppressing current temperatures below the 30 year trend by ~ 0.1 oC. (ii) analysis of ocean regime fluctuations suggests that the current regime (manifest in the negative phase of the PDO) which we've been in since around 1998 may be additionally suppressing surface temperatures by around 0.1 oC [**]. So a peculiar coincidence of well-, or reasonably well-characterised cooling forcings (solar cycle min; prolonged minimum; reduced solar output; negative PDO regime) is likely suppressing current temperatures by perhaps 0.2 oC below the 30-year trend. During the next 5-6 years we expect to "recover" 0.1-0.15 oC of that through the solar cycle "up-swing". The surface temperature has warmed with a max around 2005, and has been pretty much steady since then. Of course we can't say much about trends from a few years of data, but it seems that the CO2-induced warming is "holding its own" against a coincidence of (temporary) cooling forcings. In that light it's difficult (as you and John Cook suggest) to accommodate some of the uncharacterized proposals for contributions to surface temperature. If the cosmic ray flux (CRF) notion had merit, for example, this should be making its strongest cooling contribution since the CRF count has been right near its maximum value for the last few years [***]. Likewise if (as some suggest), the PDO index has made a major contribution to 20th century warming, the current negative PDO phase should be making a stronger cooling contribution than 0.1 oC…. .. however accommodating these contributions would require that the earth is significantly more sensitive to CO2 than we think (or hope)….or something else is countering these cooling contributions (….but what?) [*] J. L. Lean and D. H. Rind (2008) “How natural and anthropogenic influences alter global and regional surface temperatures: 1889 to 2006″, Geophys. Res. Lett.35, L18701. http://pubs.giss.nasa.gov/abstracts/2008/Lean_Rind.html [**] K. L. Swanson, G. Sugihara and A. A. Tsonis Long-term natural variability and 20th century climate change PNAS 106, 16120-16123 http://www.pnas.org/content/106/38/16120.abstract [***] http://cr0.izmiran.rssi.ru/clmx/main.htm
125348. Berényi Péter at 09:26 AM on 17 January 2010
        Skeptical Science now an iPhone app
        Riccardo, the data ARE definitive. Paltridge at al. may use a cautious language (otherwise they would risk rejection due to politically motivated peer review). But the long term decrease of specific humidity at higher levels is pronounced and can't possibly explained away. Their claim "increases in total column water vapor in response to global warming do not necessarily indicate positive water vapor feedback, since very small decreases of water vapor in the mid-to-upper troposphere can negate the effect of large increases in the boundary layer" is based on sound physical principles. Except it is far from being sure that decrease in upper troposphere moisture is caused by "global warming" as such. It may be a more direct effect of increasing carbon dioxide levels. Satellite measurements of the same trend are unreliable. It is easy to see why. They are trying to detect minuscule changes against an increasing lower troposphere background humidity signal from far away. In cases like this, one would prefere in situ measurements. The Dessler at al. paper you cite speaks about short term feedback. That's a completely different beast. Paltridge at al. also discusses this question. Finally I don't think the norm in climate science should be any different from those of other sciences. It's truth, plain old truth. doug_bostrom: "I understand it's vital that you avoid talking about actual data and observations" I do understand that you don't understand I'm talking about actual data and observations right now. "be careful what you wish for, it may prove to be more confirmation of something you don't like" I wish for truth, not memes. If it's something I would not like, that's it. Wishes, fears, politics should be left to the general public. There is no other way to do science. "Got a cite on that?" Tons ARIS CO2 maps at the NASA site. NASA ARIS Mid-Tropospheric (8 km) Carbon Dioxide July 2003 http://photojournal.jpl.nasa.gov/jpegMod/PIA09269_modest.jpg "your preconception is no amenable to change" My preconception is that philosophia naturalis should proceed by validating theory agains measurement. This preconception is not amenable indeed. Theoretically motivated dismissal of huge bodies of actual data is not the way to go. "Satellite observations are inconvenient if you're a doubter, so any chance to undermine our confidence in them will be seized" You get it wrong. I was talking about specific satellite measurements and I was not trying to "undermine your confidence in them". I have nothing agains satellites per se. But when the systematic error and/or the error bars are larger than the values to be measured, the measurement is useless, even if it cost a lot of money. You don't have to have any "confidence" in data. You should just understand the exact measurement process and confide in your own understanding. If you do that, it can't be "undermined". Data is an inconvenient(?) truth, agreed.
125349. David Horton at 09:07 AM on 17 January 2010
        2009 - 2nd hottest year on record while sun is coolest in a century
        Kelly O'Day and Ned. Call me suspicious and cynical, but I'm guessing that "John P" is just an internet bot. Programmed to respond to key words and then instantly pasting in the same chunk of text. Often this technique is used to advertise porn sites, or via-gra sales, so using it for denialism seems about right. The reason? To ensure (I'm guessing) that every climate change thread anywhere in the world contains denialism material in order to make it seem that there is active debate - "see, the science isn't settled". On the other hand denialist sites, I understand, rarely allow any dissenting posts, conveying the image of overwhelming consensus that "the science isn't settled". If it was me I would delete this stuff, but the cleverness of it is that it looks just like genuine questions, and deletion would have denialists screaming censorship (as distinct from the culling that they engage in). I reckon perhaps the best tactic is simply to ignore anything that smells to high stratosphere. There is no debate on the core of climate change science, however much there might be on precise details. The situation is exactly like evolution where creationists seize on minor debates ("stochastic evolution" "sympatric speciation") to pretend the science is under question. Snow in Minnesota in Winter doesn't quite rise to the level of sympatric speciation as a debating point.
125350. Doug Bostrom at 09:03 AM on 17 January 2010
        2009 - 2nd hottest year on record while sun is coolest in a century
        NewYorkJ at 08:22 AM on 17 January, 2010 "I took a look at your graph. It did not contain a linear trend line. Just eyeballing it, I suspected that your assertion was wrong, so I plugged the annual numbers into a spreadsheet and added a linear trend line (a good exercise for you to do as well). The change has been about +0.5 C from that single station's period of record. Thus, your assertion is incorrect." A step very few will take, sadly, but thank you. For those with a powerful sense of curiosity but a limited budget, the spreadsheet included in OpenOffice makes NewYorkJ's example extraordinarily easy to follow. Put the data in a column, select the column, use the "insert graph" option, turn on a trend line. Voila. Caveat: OO is a powerful tool but for the relatively ignorant (such as myself) don't go too far with conclusions when so armed, heh!

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