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Comments 124601 to 124650:

124601. Riccardo at 01:40 AM on 7 February 2010
        Increasing CO2 has little to no effect
        matt sykes, #2 fig. 1 is a difference spectrum between 1976 and 1990. It shows only the changes during this period of time. If you want to compare the spectrum in fig. 3 (an emission spectrum), you need an absorption spectrum from space looking down. You can play with this using calculated spectra #3 there's much more energy in the visible than IR coming from the sun. It is this that warms the earth, not the IR. As far as CO2 absorption is concerned, it's not true that the IR around the 700 cm-1 band is much more than what the earth emits at the same wavelength. Integrating it over all the IR is wrong. Then the earth emits in the IR and this emission happens to peak around a CO2 absorption band; part of it is trapped producing warming. This is the very basics of the greenhouse effect. #4 The lifetime of the excited state is of the order of nano- to -micro- seconds depending on temperature and pressure. The extra energy can be released in two ways, by re-emission of a photon or by thermalization by collision (warming) of the surrounding air molecules; the re-emitted part will be absorbed again by other CO2 molecules and the process repeats itself until the pressure is so low that the photons have a high probability to escape to empty space. This is the way it works, again the basics of the greenhouse effect. If you increase CO2 concentration you slow down the process. You clearly still get cooling at night but not all of the energy absorbed during the day. It is not going to happen even if you do not increase CO2. A good example is the moon which, having no atmosphere, have enormous temperature gradients across the day/night line. I would more easily believe in your genuine interest had you not said "that logically there seem to be problems with the theory". Given that dozens of really smart people have worked on this for decades you'd better ask yourself "am i missing something?".
124602. ConcernedCitizen at 22:05 PM on 6 February 2010
        Increasing CO2 has little to no effect
        @Ricardo. Point #2. That doesnt answer my question. Graph 1 shows energy being absorbed by all the gasses mentioned. Graph 2 shows enery be emitted by only some of them. Thats my point. How is it selective so that only some of the gasses emmit energy back o the surface which is what the second graph implies? Point #3. Energy ballance. So an increase in CO2 will absorb, and re-emit to space more IR from the sun as well as absorb and re-emit to earth more IR from the earth. Since the sun produces more IR than the earth how does the extra CO2 cause warming and not cooling? Point #4. Excited state duration. If the duration is less than 12 hours then all the energy absorbed by CO2 during the day will be lost at night. How does this generate net warming over a period of days-years? I am not being argumentative, I am geneuinely interested in the science behind GH gasses, it is just that logically there seem to be problems with the theory. I am glad you mentioned excited state durtation by the way because I could not find any information on this online and to me it is a critical factor in heat storage.
124603. Doug Bostrom at 19:39 PM on 6 February 2010
        What the IPCC and peer-reviewed science say about Amazonian forests
        By the way, the little "gotcha" on the Kehrwald paper does not affect the actual significance of the work, which has to do with ice cores revealing a long term mass imbalance: "Ice cores drilled from glaciers around the world generally contain horizons with elevated levels of beta radioactivity including 36Cl and 3H associated with atmospheric thermonuclear bomb testing in the 1950s and 1960s. Ice cores collected in 2006 from Naimona’nyi Glacier in the Himalaya (Tibet) lack these distinctive marker horizons suggesting no net accumulation of mass (ice)since at least 1950. Naimona’nyi is the highest glacier (6050 masl) documented to be losing mass annually suggesting the possibility of similar mass loss on other high-elevation glaciers in low and mid-latitudes under a warmer Earth scenario. If climatic conditions dominating the mass balance of Naimona’nyi extend to other glaciers in the region, the implications for water resources could be serious as these glaciers feed the headwaters of the Indus, Ganges, and Brahmaputra Rivers that sustain one of the world’s most populous regions. As Charlie A so helpfully demonstrated by pointing out Thayyen and Gergan's paper, losing significant ice in the general region concerned will have significant hydrological impacts. So at the end of the day, the bloody WWF imbroglio once again affects nothing in actual physics, but this was sure an object lesson on how much irritation it must be causing in academic circles.
124604. Doug Bostrom at 19:17 PM on 6 February 2010
        What the IPCC and peer-reviewed science say about Amazonian forests
        thingadonta at 18:36 PM on 6 February, 2010 It all sounded so reasonable, sort of, until you got to this part: "I suspect, your comments about the CFC are also misguided. I suspect most of the rise /declne in ozone is probably natural, and unrelated to human activities. Academia is stuffed and stacked with people searching everywhere for human effects on natural systems- its the very reason for their academic existance, so they sometimes see human effects which are simply not there, and/ or natural (global warming). " A neat trick, sort of a deck of jokers. Any findings having to do with humans interacting with their environment with which you disagree, you can put down to lying academics, without a scintilla of actual evidence, data? How credible do you think that is?
124605. Doug Bostrom at 19:11 PM on 6 February 2010
        What the IPCC and peer-reviewed science say about Amazonian forests
        Charlie A at 17:14 PM on 6 February, 2010 "I said "The dry season corresponds to the winter, near zero melt season. The melt season occurs during the summer, which is also peak monsoon season." You say "For the Ganges, about 70% of flow is glacial meltwater during summer, for many other rivers serving the enormous concentration of population in the northern portion of India, between 50 and 60%. How about the other side, China? 23% of China's population receives most water from glacial melt during the dry season. * I'm glad to see that your references agree with me." They do? "In other words, glaciers don't do the sort of seasonal smoothing that is so important in some other areas of the world." Really, did you read Thayyee and Gergan? That's not what they say. "You will find the Barnett is confusing discharge from a glacial basin with glacial melt. In other words, he adds snowmelt to glacier melt." No, what you've failed to pick up is that much snow melt is derived from glaciers. Again, I think our lack of training here is a problem. Read Thayyee and Gergan, carefully. "Perhaps Kehrwald 2008 has an error ???? " Going straight back to the WWF, if you follow his cite. Ouch.
124606. lodolite at 19:04 PM on 6 February 2010
        Guest post in Guardian on microsite influences
        Thanks, I'll go do some reading. I have no science background at all so I find reading others comments often increases understanding of what I read. Other times I just get lost.
124607. Charlie A at 17:29 PM on 6 February 2010
        What the IPCC and peer-reviewed science say about Amazonian forests
        It is often difficult to determine whether a specific change is happening due to 1) the natural warming of coming out of an ice age 2) natural variability (google Hurst Phenomena for some interesting reading. Those hydrologists at work again) 3) global warming or climate change due to well mixed greenhouse gases such as CO2 and methane, 4) other anthropogenic causes. In the case of Himalayan Glaciers, it appears that CO2 is not the culprit. http://newscenter.lbl.gov/feature-stories/2010/02/03/black-carbon-himalayan-glaciers/ Full paper is at http://www.atmos-chem-phys-discuss.net/9/26593/2009/acpd-9-26593-2009.pdf for a change, it isn't behind a paywall.
124608. Charlie A at 17:14 PM on 6 February 2010
        What the IPCC and peer-reviewed science say about Amazonian forests
        I said "The dry season corresponds to the winter, near zero melt season. The melt season occurs during the summer, which is also peak monsoon season." You say "For the Ganges, about 70% of flow is glacial meltwater during summer, for many other rivers serving the enormous concentration of population in the northern portion of India, between 50 and 60%. How about the other side, China? 23% of China's population receives most water from glacial melt during the dry season. * I'm glad to see that your references agree with me. The peak melt coincides with the peak precipitation. When the monsoon is dumping lots of water on the region, the addition of a bit of glacial melt doesn't benefit the river users much, and might actually be counterproductive if it causes flooding. And the low flow periods are during the winter, when glacial melt is negligible. In other words, glaciers don't do the sort of seasonal smoothing that is so important in some other areas of the world. Rather than take Barnett 2005 as gospel, you should click on through to his references for the related statements ... his refs 40,41, and 43. All are papers where the lead author is Pratap Sing of the National Institute of Hydrology. You will find the Barnett is confusing discharge from a glacial basin with glacial melt. In other words, he adds snowmelt to glacier melt. Again, I suggest you look at figures 3 and 8 of http://www.the-cryosphere-discuss.net/3/443/2009/tcd-3-443-2009-print.pdf Note how during the dry season that glacial melt is an insignificant percentage of the flow. Or look at Table 1 which shows that glacier melt supplies approximately 9% of total annual flow of the Ganges. ----------------------------------------- Regarding the area of glaciers in TP, you can look at the joint report by United Nations Environment Programme (UNEP) and the World Glacier Monitoring Service (WGMS). See http://www.grid.unep.ch/glaciers/ and in particular section 6.9 Regional Glacier Changes, Central Asia. "Central Asia with an estimated total ice cover of 114 800 km2 has as its dominant mountain range 0the Himalaya, where most of the glaciers occur (33 050 km2). That is consistent with other estimates I've seen. And table 3.1 from http://www.grid.unep.ch/glaciers/pdfs/3.pdf shows global estimates of ALL glaciers excepting those in Greenland, Antartic and Artic as ranging from 510,000 sq km to 540,000 sq km. Now compare that estimate to Kehrwald 2008 which says that the measured area of Tibetan Plateau glaciers was 500,000 sq km in 1995. Perhaps Kehrwald 2008 has an error ????
124609. Doug Bostrom at 16:38 PM on 6 February 2010
        What the IPCC and peer-reviewed science say about Amazonian forests
        Charlie A at 13:13 PM on 6 February, 2010 And belatedly I see your distinction between snow melt and glacial melt, something I have somewhat personal experience with as here where I live we depend to some extent on snow melt. I find it astonishing that you dismiss the findings of researchers in this field with casual references to conflation and "alarmism". The Thayyee and Gergan paper is very interesting indeed. It looks at the IPCC roll up of the general contribution of glaciers to stream flow and points out that the Himalaya should be examined more closely in distinction from the IPCC's generalized conclusions. The paper hardly seems to dismiss the role of ice and snow as an important source of water for major river systems: "River Ganga is being replenishedby the melt water from around 4000 glaciers spread over India and Nepal and the River Indus is being fed by more than 3300 glaciers. Snow and glacier melt together 5 with monsoonal precipitation determines the headwater flow regimes of large parts of the Himalayas, including central and eastern Himalayan tributaries of River Ganga and Brahmaputra. Snow and glacier melt contribution is very significant in many of these Himalayan Rivers. On an average, annual snow and glacier melt contribution is estimated to be 60% in Satluj river at Bhakra dam (Singh and Jain, 2002), 49% in 10 Chenab river at Akhnoor (Singh et al., 1997) and 35% in Beas river at Pandoh (Ku-mar et al., 2007). " Now, if you read this paper carefully, you'll see that much of the snow the authors are speaking of is that which is lying on top of glaciers. So while it is technically true that the particular portion of the Himalayan catchment they are looking at is dominated by snow melt, if the glacier this snow melt sits on vanishes clearly the hydrological picture is going to change. This portion highlights that: Figure 6 explains the role of glaciers and precipitation in controlling the river flow variations in a Himalayan catchment. While discharge at Tela and Gujjar Hut stations were reduced by 58 and 50 percentage, respectively from 1998 to 2004, discharge from the glacier catchment showed comparatively steadied response. Analysis of specific runoff from each sub-catchment showed that the contributions from Tela catchment (41.8km) reduced from 25mm/day in 1998 to 9mm/day in 2004 (Table 1). Similarly, runoff contributions from the Gujjar Hut sub-catchment (20.3km 2) reduced from 18 mm/day to 4 mm/day during the same period, whereas runoff from the glacier catchment (15.7km2) varied between 29 to 15mm/day. Variations observed in the summer specific runoff from the non-glacierised part of the catchment covering 62 km 2 are obviously driven by the variations in the precipitation. The lowest specific runoff of the glacier catchment observed during the study period was 15mm/day, which is much higher than the lowest specific runoff of 9mm/day and 4mm/day of the non- glacierised Tela and Gujjar hut sub-catchments, respectively. This highlights the buffering role of the glaciers during the years of low summer flow in the glacier fed rivers of the “Himalayan catchment”. I'm wondering if all this confusion about glacial melt versus snow melt is because amateurs are scrutinizing papers without the training needed to properly deal with terminology. I couldn't say for sure; I'm an amateur.
124610. Doug Bostrom at 15:45 PM on 6 February 2010
        What the IPCC and peer-reviewed science say about Amazonian forests
        Charlie A at 13:13 PM on 6 February, 2010 "Section 6, para 17 has multiple errors ---" There is no such paragraph in the article. You actually were referring to section 6, paragraph 18. Anyway... "The dry season corresponds to the winter, near zero melt season. The melt season occurs during the summer, which is also peak monsoon season." Wrong, or at least your generalization is much worse than what you're accusing this paper of committing. For the Ganges, about 70% of flow is glacial meltwater during summer, for many other rivers serving the enormous concentration of population in the northern portion of India, between 50 and 60%. How about the other side, China? 23% of China's population receives most water from glacial melt during the dry season. * "The surface area of glaciers across the TP is projected ... (References are available upon request)." Based on the accuracy of your claim #1, it would indeed be helpful to see those references. * http://meteora.ucsd.edu/cap/pdffiles/barnett_warmsnow.pdf
124611. kepler at 14:53 PM on 6 February 2010
        How do we know CO2 is causing warming?
        the link cited in this article requires a membership but i found a pdf copy of the article here: ams.confex.com/ams/pdfpapers/24874.pdf i must say i'm at a loss how skepticalscience arrived at the graph here - it doesn't appear in the actual paper. and in fact (in fig. 1 of the paper) the delta brightness temperature increases for the 700 waves/centimeter point (where CO2 absorbs IR). i agree that CH4 has less in 1997 than 1970 but the majority of the spectrum analyzed showed an INCREASE in emission in 1997 as compared to 1970. in that figure 1 of the paper, they show lines of average measurements and then upper and lower error lines. it is true that the lower error line dips to 0 and slightly below for the 700/cm so maybe you just reported the lower error graph. and i will agree that this wavenumber was lower than the rest but they were still above zero which shows an increase in emission in 1997 vs 1970. the authors even state in the conclusion that we shouldn't infer atmospheric temperature changes from this snapshot. here is their quote: Although these strongly affect the OLR the atmospheric temperature and humidity response cannot be unequivocally determined owing to the snapshot nature of the observations.
        Response: The graph above comes from Figure 1c in Increases in greenhouse forcing inferred from the outgoing longwave radiation spectra of the Earth in 1970 and 1997 (Harries 2001) (unfortunately the full paper cannot be found online - dang pay walls). This is a different paper to the one you link to (thanks for the link to the full paper, btw). The conclusion from Harries 2001 is 'Our results provide direct experimental evidence for a signi®cant increase in the Earth's greenhouse effect that is consistent with concerns over radiative forcing of climate.'
124612. Charlie A at 13:13 PM on 6 February 2010
        What the IPCC and peer-reviewed science say about Amazonian forests
        Doug_bostrom at 04:23 AM on 6 February, 2010 "Perhaps you'd better read the article and discover where are the errors, then mention them here specifically? " I would prefer to engage the authors in discussion, but they have failed to respond to repeated inquiries. Even better, I would expect the authors to proactively correct errors in their article to keep others from further propagating the errors. Typical misstatements: Section 6, para 17 has multiple errors --- 1) "TP ice riled are a critical resource for 1/6 of the world's population becuase they provide dry season runoff" This is incorrect for most of the TP. The dry season corresponds to the winter, near zero melt season. The melt season occurs during the summer, which is also peak monsoon season. 2. "The surface area of glaciers across the TP is projected to decrease from 500,000 sq km measured in 1995 to 100,000 sq km in 2030." There are multiple estimates of total glacier area in the TP that range from around 100,000 sq km to 110,000 sq km. None are anywhere near 500,000 sq km. (References are available upon request). Considering that these are the two major conclusions of the paper, these two errors alone are significant enough to warrant a corrigendum or errata. A couple of other errors: 3. "Himalayan glaciers have been retreating more rapidly than glaciers elsewhere in the world". There is no scientific basis for this statement. ----------------------------------------- Both this paper and Barnett et al, 2005 conflate glacier melt and snowmelt. There are many areas in the world that have no glaciers, but do depend upon snowmelt to even out seasonal variations in streamflow. Some alarmists seem to confuse glacial melt and snowmelt. O On the other hand, hydrologists at the Indian Institute of Hydrology clearly distinguish between them. See for example, Figure 3 of "Role of glaciers in watershed hydrology: “Himalayan catchment” perspective" by R. J. Thayyen12 and J. T. Gergan. Or look at Figure 8 which has monthly variations in discharge and percentage contribution from the glacier catchment in the stream flow.
124613. Charlie A at 12:55 PM on 6 February 2010
        What the IPCC and peer-reviewed science say about Amazonian forests
        Predictions are key to testing a hypothesis. Of course, if one puts forth a hypothesis of Anthropogenic global warming in such an unclear fashion that the actual hypothesis is unclear and any predictions (ooops, I mean projections) made are also unclear, then it is impossible to falsify the hypothesis. A untestable, unfalsifiable hypothesis is more akin to a faith. One may or may not believe in God, but God's existence is an untestable, unfalsifiable hypothesis. It is best to avoid such types of hypotheses in true science.
124614. Marcus at 12:01 PM on 6 February 2010
        What the IPCC and peer-reviewed science say about Amazonian forests
        Doug_bostrom, this sudden switch from attacking the science of global warming to attacking the predicted impacts of global warming-as suggested by the IPCC-seems indicative of a rear-guard action by the so-called skeptics. Unless I'm wrong, rear-guard actions are only performed by the side which is *losing* the war-which suggests to me that, for all their bluster & bravado, the skeptics *know* they're losing the war over the science, so are desperately trying to nit-pick the predictions of the IPCC in some desperate bid to save some face.
124615. Doug Bostrom at 11:52 AM on 6 February 2010
        The role of stratospheric water vapor in global warming
        SNRatio at 09:02 AM on 6 February, 2010 Thanks! I've only been looking seriously at this whole topic (climate change) for a few months but have already been spiraling toward the ocean because it's -so- bulky, so loaded with thermal inertia yet ineluctably a big influence on us air breathers and our climate. The energy quantities in the ocean are just staggeringly large, compared to the atmosphere. Over on RC a favorite skeptic and I were comparing notes on the amount of additional energy flowing into the Arctic ocean due to the ice anomaly there. His figure was more realistic than mine, I think, a "mere" 40TW of additional juice pouring into the ocean on a typical summer day. I think the actual power level would be a bit larger than that if the the numbers were done rigorously, but all the same we found ourselves agreeing on how these numbers are so large they entirely exceed our intuitive grasp. And the ocean sucks up this energy without batting an eye, at least over the short term. Remarkable. I'm curious to know what'll happen over the long term in the Arctic; thermohaline circulation is obviously dependent on Arctic ocean temperature. Meanwhile, just like everything else in nature there's likely little or no "overengineering" in the way the present circulation works, it's more something that's converged on some sort of quasi-stable behavior. A little sneeze from the ocean can mean a lot up here.
124616. Doug Bostrom at 11:37 AM on 6 February 2010
        What the IPCC and peer-reviewed science say about Amazonian forests
        Seems to be quite a fad, picking over the IPCC report, but all that seems to be coming off is a bit of gristle. No meat? Nothing about the physics?
124617. SNRatio at 09:02 AM on 6 February 2010
        The role of stratospheric water vapor in global warming
        @ doug_bostrom, 51 I really appreciate that you raise those questions, and I think you give important elements of possible answers. I'll try to expand a little, very speculatively, as I'm a merry amateur in this field. First, the ENSO events aren't just simple breathing in and out of ocean heat. Surely, lots of the heat released during an ElNino was stored during LaNina conditions, but LaNina will often be associated with "impaired" radiation balance, cloud conditions effectively increasing albedo etc. Therefore, the energy uptake can be much smaller than average during strong LaNinas - you can get an indication of this if you look at sea level rise during the last years - it has continued at constant or somewhat falling surface temperatures, but more slowly. Indicating continous ocean heat uptake, but at a reduced rate. On the other hand, in ElNinos, it seems that radiation imbalance may actually increase, in spite of hotter conditions. That may lead to a temperature increase beyond what is "supported" by the normal conditions, and temperatures fall after the episode. Not because of negative radiative balance, heat still accumulates these days, but - I think we may formulate it this way - because of _less positive feedback_. In addition to ENSO events, Mojib Latif has pointed to a ca 60 yr cycle in the NH, and the rapid temperature increase 1980-2000 may in part come from this, maybe 0.05-0.1 degC/decade. And we have the solar cycles accounting for maybe 0.1 degC. Putting all this together, I think we may have a reasonably good explanation of the events of the last 10-15 years. Maybe more deterministically inclined people dislike the variability in feedbacks - but this I think is a fact of life in climate. I interpret the changes in stratospheric water vapor content discussed here as an important example of such variable feedbacks. It has been observed once, and I can't understand why it should not happen, over and over again. And with increased energy content of the troposphere, we might expect more of it, as it seems mainly to be an effect of that, to a lesser extent of CH4 degradation.
124618. Riccardo at 05:39 AM on 6 February 2010
        What the IPCC and peer-reviewed science say about Amazonian forests
        oracle2world, could you please quote where in the report it is written?
124619. oracle2world at 05:26 AM on 6 February 2010
        What the IPCC and peer-reviewed science say about Amazonian forests
        Stop apologizing for the IPCC - the latest is the claim that 55% of the Netherlands was below sea level. The Dutch government says 26%. Now this is not a hard figure to check. Any wonder why folks suspect the rest of the report is equally sloppy?
124620. miguelveraleon at 04:40 AM on 6 February 2010
        CO2 lags temperature
        Hi John, I really appreciate your effort to explain the science of climate change. Your posts have helped me to solve a lot of doubts I had about the subject. I have a question regarding this graph. When the CO2 forcing is added to the Milankovitch cycles forcing after the triggering of deglaciation, shouldn't there be a noticeable increase in the rate of warming? Or is it too small to be noticed?
124621. Doug Bostrom at 04:26 AM on 6 February 2010
        The role of stratospheric water vapor in global warming
        Ber�nyi P�ter at 20:43 PM on 5 February, 2010 "The Solomon event is likely just a major "avalanche" among many others, happening all the time on all scales." To make a case for that you need to show it with details. Simply saying "look, this test is only used in this field, therefore I'm suspicious of its validity" is not a case, it's sheer speculation. I know from other things you've written here that you can do better.
124622. Doug Bostrom at 04:23 AM on 6 February 2010
        What the IPCC and peer-reviewed science say about Amazonian forests
        Charlie A at 18:47 PM on 5 February, 2010 "A 2008 article published in Geophysical Research Letters states that "�The surface area of glaciers across the TP is projected to decrease from 500,000 km2 measured in 1995 to 100,000 km2 in 2030 [Cruz et al., 2007],� It's right there in peer reviewed literature --- most of the glaciers in the Tibetan Plateau will be gone by 2030! Perhaps you'd better read the article and discover where are the errors, then mention them here specifically? For instance, one might find that ice will retreat with a steep initial slope over time, with a flattening of the slope as time passes, meaning that the ice will never actually disappear as you imply but the authors apparently do not. It's impossible to tell from the little you write, you'll need to provide much more detail before anybody will find your suspicions credible.
124623. CBDunkerson at 02:08 AM on 6 February 2010
        What the IPCC and peer-reviewed science say about Amazonian forests
        Charlie and Berényi, I don't think anyone is suggesting that the process of peer review magically transforms humans into infallible beings. To be human is to err. Scientific peer review can help to reduce the frequency and severity of errors, but not to eliminate them. That said, there actually has been quite a bit of research on Himalayan glaciers which the IPCC will be able to draw on for AR5. Not enough to make definitive projections, but estimates have been made based on a few different methodologies. They won't be saying 'all gone by 2035' again, but don't be surprised if it is along the lines of '66% gone by 2050'.
124624. Riccardo at 01:47 AM on 6 February 2010
        Increasing CO2 has little to no effect
        1) different satellites and/or instrumets are always calibrated against one another in a better way than just the reading on a single day. 2) the first graph is a difference between spectra taken in two different points in time; the second graph is just a point in time. The difference depenss on how much the relative contrbution changed over time. IR from the sun is indeed absorbed by CO2. When you calculate an energy balance in a layer of the atmosphere you take both the incoming and outgoing energy into account. The tiny amount of energy (one and something W/m2) taken up by increasing CO2 will not make the earth look like Venus but it's enough to increase the temperature by a couple of degrees, maybe three by the end of the century. That's unfortunately enough to produce a significant change in the biosphere. There is no saturation effect to help us. The lifetime of the CO2 excited state is short enough for the CO2 molecules to be ready to absorb more of the incoming photons.
124625. psilax at 01:29 AM on 6 February 2010
        It's microsite influences
        Questions: 1) The belgian media jumped on a result similar to what is posted on http://surfacestations.org/ of summer 2009 (no source reference in Belgian media) in which it seems that a lot of american surface stations have a deviations of more than 1°C and that for some "accurate" surface stations the temperature has been decline the last 100 years. Is this already incorporated in the graphs above? (No post date of the graphs). 2) Why do your graphs only go back to 1980 while other stations have data going back more than 100 years on the graphs of surfacestations.org?
124626. Riccardo at 01:28 AM on 6 February 2010
        On the reliability of the U.S. Surface Temperature Record
        Alexandre, the difference is what they measure. Satellites measure the whole lower troposphere while surface stations just a few (usually two) meters above the surface.
124627. ConcernedCitizen at 00:52 AM on 6 February 2010
        Increasing CO2 has little to no effect
        Some quesitons. 1) Graph one is derrived from the difference between two satelites launched 26 years apart. How are their sensors callibrated so that they would give the same readings on the same day? 2)Graph 2. Why is there no downward radiation for CFCs, HNO3 NO2 etc, as there is for CO2, when the first graph shows that their energy is being 'trapped' in the atmosphere? Additionally. from the picture showing solar light penetrating the atmosphere but terrestrial IR being trapped, what happens to the solar IR? The sun produces aproximately 400000 times as much IR at the frequency absorbed by CO2 as the earth. The atmosphere must therefore absorbs and re-radiate half of this back into space. Also given the far larger solar IR radiation the CO2 will be saturated. Additional IR from the earth is a tiny amount in comparison. Answers appreciated.
124628. Alexandre at 23:14 PM on 5 February 2010
        On the reliability of the U.S. Surface Temperature Record
        A bit OT, yes, but still on temperature records: Sattelite time series, like the UHA, show a much stronger El Nino peak in 1998 (which makes for a favorite source for guys like Watts). Where does the difference come from?
124629. Berényi Péter at 20:43 PM on 5 February 2010
        The role of stratospheric water vapor in global warming
        doug_bostrom at 18:09 PM on 5 February, 2010: "Was there some specific issue with that treatment that bothers you?" Yes, definitely. Just google for "sandpile avalanche dynamics". Highly nonlinear, self-organized sytems (like climate/weather) often show this kind of intermittent behavior. The sloppy phrase used by mainstream climate science to identify phenomena like this is "natural variability". Now. Take a simple sandpile model, generate pile weight time series, apply SNHT and you are left with an ever growing sandpile. The Solomon event is likely just a major "avalanche" among many others, happening all the time on all scales.
124630. Berényi Péter at 20:19 PM on 5 February 2010
        What the IPCC and peer-reviewed science say about Amazonian forests
        Charlie, we have already done with this issue. The "Cruz et al., 2007" reference in the Kehrwald et al. paper is to IPCC AR4, WG II Report, chapter 10. Figure 10.4, letter "s" omitted. http://www.skepticalscience.com/IPCC-2035-prediction-Himalayan-glaciers.html#7875 Basic circular reinforcement technique of new age science at work.
124631. Charlie A at 18:47 PM on 5 February 2010
        What the IPCC and peer-reviewed science say about Amazonian forests
        Peer reviewed literature is not the holy grail many assume. For example, in the 5th assessment report, IPCC can use peer reviewed literature to make essentially the same claims about glacier melting that were made in AR4. A 2008 article published in Geophysical Research Letters states that "“The surface area of glaciers across the TP is projected to decrease from 500,000 km2 measured in 1995 to 100,000 km2 in 2030 [Cruz et al., 2007],” It's right there in peer reviewed literature --- most of the glaciers in the Tibetan Plateau will be gone by 2030! Ref: “Mass loss on Himalayan glacier endangers water resources”, Kehrwald, etal Geophysical Research Letters Vol 35. doi:10.1029/2008GL035556 http://bprc.osu.edu/Icecore/Kehrwald%20et%20al%202008.pdf This article has very many other "interesting" statements. All in a peer reviewed journal. All available for the IPCC to cite in the next assessment report.
124632. Doug Bostrom at 18:09 PM on 5 February 2010
        The role of stratospheric water vapor in global warming
        Berényi Péter at 09:38 AM on 5 February, 2010 "I know what SNHT is supposed to be, even if I've never heard of a Standard Cylinder Compression Test. However, if there is such a thing, it makes sense to test any kind of cylinder the same way which should endure high pressure, not just those in combustion engines, e.g. hydraulic cylinders come to mind." Hah! The second I hit "submit" I knew I'd been insufficiently specific. The point I was trying so foolishly to make is that certain tests are going to be confined in utility to narrow ranges and types of inquiry and that by itself should not and does not mean they are invalid. The specific test I was referring to was one where an IC engine crank and camshaft are rotated such that valves are closed and the cylinder under test is at top of travel. All cylinders in that state should yield reasonably similar pressure readings and should hold that pressure for similar periods of time, all those readings should be within a specification range. This test is an excellent diagnostic for IC engine cylinder wear, would be inapplicable to most other machinery but is nonetheless very valuable as well as uncontroversial. The test you were referring to is used to process not only temperature but also other meteorological readings such as precipitation gathered from multiple sites. It's going to be of no utility in many other fields. It also does not appear to be controversial. I'm not an expert, obviously. Was there some specific issue with that treatment that bothers you?
124633. Doug Bostrom at 17:54 PM on 5 February 2010
        What the IPCC and peer-reviewed science say about Amazonian forests
        thingadonta at 13:51 PM on 5 February, 2010 Your examples of previous instances of natural variability are poor analogies to the situation we are now creating. From various historic examples it appears uncontroversial that we have the ability to exert significant power over various ecological systems, as exhibited by extinctions of various species we've accomplished. The scope of our ability to modify planetary systems also appears rather uncontroversially to have been steadily increasing, as demonstrated by CFC emissions and our subsequent successful initiation of reversal of CFC impacts on the upper atmosphere, or for that matter acidic emissions from industrial sources. These events and the story they tell of our growing capability to harm ourselves beg a couple of questions. Should we continue doing so even after we've developed the skills to perform in a more competent way? Are we in control of ourselves sufficiently to choose the changes we impose? The answers will not come from nature, the responses must come from us.
124634. Pat T at 17:39 PM on 5 February 2010
        It's cooling
        If your kid grows an inch and a half each year between fifth grade and eighth grade and then doesn't grow any more through high school, is he still growing? No. And if someone says "but but but his average height during high school is taller than his average height during middle school!" does that change your mind? It's not still warming. It's still warm. Perhaps it shouldn't be - the known natural forcings over the last decade should perhaps have caused cooling but haven't yet. Is 1998 "cherry picking one year?" No. It's one year of natural variability - but 11, going on 12, years of CO2 emissions. And 1998 is warmer than - or if you use GISS, within 0.01 deg C as warm as, each year since then. If 11 becomes 15 or 20, that's the skeptics' point - - if the climate is as CO2-sensitive as is thought, then no single year of natural variability should offset two decades of cumulative CO2 buildup. 11 hasn't become 15 or 20, so I don't think that "it's still warm though it's neither warming nor cooling" disproves your thesis. So one has to ask, why continue to belabor the point? I understand that "it's still warm even though perhaps it shouldn't be" is complex and you might lose people at the lowest common denominator, but when you oversimplify to the point that you've reduced the thesis to a statement that isn't really accurate, you lose some critical thinkers - as with the "anthropogenic cause of tree ring divergence," this practice probably fuels more skepticism than it quells.
        Response: I understand the use of metaphors but eventually metaphors get so tortured, the usefulness fades. In the case of the 'growing kid' metaphor, an appropriate comparison would be if you had a child that would grow 2 inches in one year, shrink 1 inch the next year, grow 1.5 inches the year after that, shrink .5 inches the next year. His height is shooting up and down but gradually in the long term rising. But really, that's just a weird metaphor!
        
        Don't be beguiled by the year 1998. Be aware that the HadCRUT record which finds 1998 as the hottest year on record doesn't include the whole globe - it excludes regions where the warming trend is greatest. A fully global temperature record finds 2005 as the hottest year on record, 2009 as the 2nd hottest year on record and a statistically significant warming trend throughout this period.
124635. Pat T at 17:20 PM on 5 February 2010
        The hockey stick divergence problem
        1) The spaghetti graph a) has its own issues discussed in climateaudit, b) isn't a hockey stick but rather shows a MWP within half a degree C of late 20th century temps and that lasted a few centuries and didn't result in runaway warming, and c) doesn't include Loehle, which shows a more pronounced MWP. 2) None of the direct evidence for the MWP has been addressed (except for realclimate's thesis that, because after 900 years of breeding grapes for cold-hardiness and advances to growing techniques, they now again have vineyards in England, somehow that means that it must be as warm now as it was when they had vineyards 900 years ago). We're talking about acknowledged history from nearly every corner of the world. If someone were to tell you that based on examination of the Delaware River or the soil underneath it or some other indirect physical proxy, Washington and his men couldn't have crossed it with their horses and gear that night, would you accept this without an explanation as to how it is that the next morning they were on the other side? 3) Right - tree rings are reliable within the temperature range experienced between 1880 and 1960. Above those temperatures they're not reliable - the most obvious explanation is that once you get above the temperatures experienced in 1960, the correlation between tree ring width and temperature falls off. There are other possibilities but there's one clear, obvious explanation that you really have to want to reject in order to reject it. The mental gymnastics engaged in to defend the notion of an anthropogenic explanation for the tree ring divergence is a prime example of what I'm talking about. You fall back on logical contortions to defend aspects of your thesis that could be discarded without jeopardizing your main point. This tendency turns critical thinkers into skeptics. If you just said yep, the MWP was warmer or comparably warm for 200 years but the CO2 we're emitting won't go away and so eventually we're going to have a problem, especially if whatever caused the MWP happens again, I'd be inclined to believe you. There are a lot of skeptics who are skeptics primarily because of this and other needless exaggerations (such as "it's still getting warmer" rather than "it's still warm and it shouldn't be given that natural forcings are have been on the cool side for 3-4 years"). I think the overzealous AGW proponents do their cause more harm than good.
124636. mazibuko at 15:16 PM on 5 February 2010
        What the IPCC and peer-reviewed science say about Amazonian forests
        Thingadonta: "What the WWF fund and other green groups fail to appreciate is that if the forest size reduces/expands quite naturally, why is there so much concern from human activities?" The concern is that human activities alter forest cover far more rapidly than the changes experienced during glacials/inter-glacials. Species adaptation is much easier when a habitat change occurs gradually. A species, particularly an endemic with a narrow range, will struggle to adapt if a large portion (or all) of its habitat is clear-felled within the course of a few months or years.
124637. Tom Dayton at 14:59 PM on 5 February 2010
        What the IPCC and peer-reviewed science say about Amazonian forests
        thingadonta, "a high natural species turnover" contradicts "species adapt to this."
124638. thingadonta at 13:51 PM on 5 February 2010
        What the IPCC and peer-reviewed science say about Amazonian forests
        The Amazon rainforest was severely reduced in size during any of the geologically recent ice ages. This is well-known in the peer reviwed literature. Since these drastic reductions occur naturally, there is no reason to be overly concerned with the forest shrinking/expanding in the first place, (which isn't even mentioned above). The supposed 'lungs of the earth'(a ridiculous term, seeing as northern termperate forests dwarf the size, and effect, on C02 of the Amazon forests) have expanded and receeded markedly during recent glacials/interglacials, meaning all this nonsense about species-area vulneribility with regards to the Amazon is rubbish. There is obviously a high natural species turnover within the Amazon durng glacials/interglacials. Sepcies adapt to this. I the Amazon reduces in size with warming, (which is opposite to what it shoudl do, since it reduces in size with cooling in glacials) its nobig deal. What the WWF fund and other green groups fail to appreciate is that if the forest size reduces/expands quite naturally, why is there so much concern from human activities? It's is a fair question, depsite all the rhetoric.
124639. Riccardo at 09:59 AM on 5 February 2010
        What do the hacked CRU emails tell us?
        To whom it may concern, Penn State inquiry finds no evidence for allegations against Michael Mann. Here the full report of the inquiry panel
124640. Berényi Péter at 09:38 AM on 5 February 2010
        The role of stratospheric water vapor in global warming
        doug_bostrom at 07:35 AM on 5 February, 2010 'Lots of "no" here' I know what SNHT is supposed to be, even if I've never heard of a Standard Cylinder Compression Test. However, if there is such a thing, it makes sense to test any kind of cylinder the same way which should endure high pressure, not just those in combustion engines, e.g. hydraulic cylinders come to mind. If SNHT is a valid statistical procedure, it should make sense to apply it to time series analysis in general, not just climate data. The definition itself is rather formal, never mentioning climate. It is a plain a mathematical procedure. Could you kindly explain why one should not apply it to mortality data? Of course it would be rather easy to get rid of plagues this way, but that's exactly the point.
124641. Marcus at 09:35 AM on 5 February 2010
        The role of stratospheric water vapor in global warming
        RSVP, I was merely saying that a fall in industrial output is *not* the reason for the slower rate of climate change over the last decade, because I've seen no evidence that industrial output *has* fallen. The drop in SWV & TSI are far more likely explanations for the slower rate of warming. Trust me, I am *not* one of those people that goes around saying "we shouldn't do anything about pollution because is just going to fill the gap". Indeed, I really *hate* these people as the cop-outs they are. In truth, China & India are already doing significantly more to reduce their pollution levels-per capita-than what most Western Nations are (with the possible exception of Northern Europe). Hope that clears things up!
124642. Doug Bostrom at 07:35 AM on 5 February 2010
        The role of stratospheric water vapor in global warming
        Ber�nyi P�ter at 07:16 AM on 5 February, 2010 "could you show me a single serious application of the so called "Standard Normal Homogeneity Test" No. Now, let me ask you a question: Can you show me an example of a cylinder compression test used outside of internal combustion engine maintenance? No? Why not? Because it's a technique used for a specific, narrow range of inquiry. Does that mean it has no value? No, again. Lots of "no" here. Learn more about the "Standard Normal Homogeneity Test" here: http://scholar.google.com/scholar?start=60&q=%22Standard+Normal+Homogeneity+Test%22&hl=en&as_sdt=100000000000000
124643. RobM at 07:22 AM on 5 February 2010
        On the reliability of the U.S. Surface Temperature Record
        jpark, Jones never said that the UHI didn't exist, he said it hadn't changed in London over the time period in question. Which makes sense, considering how long the city has been developed.
124644. Berényi Péter at 07:16 AM on 5 February 2010
        The role of stratospheric water vapor in global warming
        guys, could you show me a single serious application of the so called "Standard Normal Homogeneity Test" (SNHT) outside climate science? Anyone?
124645. jpark at 06:39 AM on 5 February 2010
        On the reliability of the U.S. Surface Temperature Record
        HI ys I saw that - if one has to 'correct' for it then presumably Jones was not right in saying it did not exist - which I think is the main point Pielke is making. I will see his son debate with Bob Ward this Friday in London - I hope it is enlightening.
124646. Riccardo at 06:24 AM on 5 February 2010
        Sea level rise is exaggerated
        Arno Arrak, we all know that Al Gore didn't quote any time span for the 20 feet rise. We all also know for sure that the sea level will not stabilze by the end of this century. Comparing Al Gores number with a one century rise is (intentionally?) misleading.
124647. Riccardo at 06:16 AM on 5 February 2010
        On the reliability of the U.S. Surface Temperature Record
        jpark, ironically, the question asked by Pielke Sr. and you has an answer in the very same post. When he quotes Willby paper to assess the UHI effect in London, the very same comparison can be used to check for a difference in the trends. I don't know if Jones at al. used these two stations, but for sure this is the way UHI effect on a trend is checked and corrected for, if any.
124648. Pat T at 04:54 AM on 5 February 2010
        The hockey stick divergence problem
        This just seems like a pattern - when the evidence doesn't support the theory as you've written it, you change the evidence instead of the theory, when it would take only a minor adjustment to the theory to maintain its viability. It's very stubborn, it's unnecessary, and ultimately it detracts from your credibility. Tree ring width is affected by many factors besides temperature. Tree growth is obviously affected by many factors besides temperature - predators, sunlight, water, etc.... You can throw up these other remote possibilities but the obvious explanation is that the linear relationship between tree ring width and temperature breaks down above certain temperatures, which means that the absence of wider tree rings during a given period doesn't mean it wasn't warmer then. Why go to all the effort to string together an alternative thesis just so you won't have to budge on the "hockey stick" when you don't need the hockey stick? Sometimes you're wrong. It's better for your credibility to admit it and move on. It's clever, it's lawyer-like, to come up with "well the divergence must be anthropogenic too" but it's transparent. Don't risk losing credibility over a sub-issue that isn't necessary to make your larger point - - don't lose the forest for the trees!
        Response: I think a few clarifying points are in order as many misconceptions re the hockey stick still prevail:

        1. The hockey stick is not dependent on tree-rings. There are a number of proxies independent of tree-rings that give the same result.
        2. The hockey stick is not the smoking gun proof of human caused global warming. It shows past temperature change, not what's caused it. Sure, it's suggestive and visually persuasive but from a scientific point of view, it does not constitute proof.
        3. The reason tree-rings are considered reliable before 1960 is because there is close correlation between tree-ring proxies and the instrumental record for the periods where the two overlap (Briffa 1998).
        4. Personally, I have no emotional investment in the hockey stick. If it turned out it was erroneous and past climate change was greater than currently thought, this would mean climate is more sensitive than we currently think. This means the climate response to the extra heat trapped by CO2 will be even greater.
        5. Lastly, the peer review science doesn't say the divergence MUST be anthropogenic. It says the "decline in tree growth may have an anthropogenic cause". As the cause is yet to be definitely defined, it's speculation at this point. Similar to the hockey stick, it's not hard proof but it's suggestive. 

        This is not a case of "hockey stick" versus "not a hockey stick". This is a case of considering all the various proxies together and determining what is the most accurate temperature reconstruction.
124649. Svatli at 04:28 AM on 5 February 2010
        What the IPCC and peer-reviewed science say about Amazonian forests
        I'm always surprised when the "argument", "that it's all a lie" comes in to the discussion. But to adress the problem at hand. My view of these matters is that the world is warming up, as the science is making clearer to us by various studies. In the future (even now) there will be climate changes as a result of this warming. Of course there are some uncertanties about how these changes will be in the future, expecially if we are talking about some specific areas (like the Amazonas). But also these changes in climate will have some consequence in the future and science is trying to adress those questions as well as possible, with scientific studys. Of course there will be some mistakes made, but overall I don't think the mistake is the big issue (and of course we'll have to learn from them). With all this noise beeing produced by some "critics" it's going to take more time then it should, but if that's the process we have to go through, well then thats what we'll do. It's amazing how some arguments do evolve and how the small issues are sometimes made to look like as they are the whole picture. The big picture in my mind is that the climate is changing because of human emission of CO2, there will be consequences of these changes, but how severe is up to us, because we are starting to get the pieces together to make the big picture even better.
124650. Pat T at 04:18 AM on 5 February 2010
        The hockey stick divergence problem
        Man-made divergence? That definitely falls into the "oh come on" category. The divergence problem is "unprecedented" and therefore must be anthropogenic? That's quite a reach. The most logical explanation would seem to be that the relationship between tree ring width and temperature changes above a certain temperature level - the level experienced in the 1960s. That means that tree rings are a useful proxy for temperatures up to that level. It also means that tree rings are not useful beyond that level - i.e., it means that when it's warmer than it was in the 1960s, it's not going to show up in tree rings, thus the fact that tree rings don't show higher-than-1960s-temperatures during past periods doesn't mean it wasn't warmer during those periods. And when you take the tree rings out of the equation, voila, the pre-hockey-stick climate history re-emerges. Does the inability to rewrite the climate history preclude man's involvement in the climate changes that have occurred over the last century? No. But the effort to rewrite the climate history adversely affects the credibility of those arguing that man has been deeply involved in those recent climate shifts. So why go through the effort? Tree lines were higher in mountain ranges around the world, including the Sierra Nevadas and Alps. The droughts were so severe in North America that they were a factor in forcing the Anasazi to abandon their elaborate cliffside dwellings. American Indian legend holds that the buffalo migrated far to the north to richer grassland. The Vikings sailed the North Atlantic in wooden boats on ice-free waters (that would during the 14th century become choked with icebergs - i.e., from sea ice breaking off much like today) and maintained a colony on Greenland - and the settlers' diets were for 200 years 80% land-based. They maintained vineyards in England (and the fact that after 900 years of breeding new varieties of grape and improving technology for cold-hardiness British wine production has reemerged is really not a counterpoint). Olive trees in Cologne. Glacial retreat in the Alps is revealing archaeological finds from the MWP - items left behind by traders using mountain passes only now resurfacing. Lake Naivasha in Kenya dried up for 200 years. Further evidence has been found in Mongolia, Japan, the Arctic and Antarctic. And don't forget the countless contemporaneous observations. These have not been explained away as having occurred for reasons other than warmer temperatures, and they cannot be dismissed as "merely anecdotal evidence." These examples all occurred during the 1000 AD - 1200 AD timeframe. That there were a few cold years in between is about as relevant to the "geosynchronous" nature of the MWP as the fact that the United States had its third coldest October on record last year is relevant to geosynchronous warming now. Even if some combination of boreholes and other indirect evidence indicates an MWP slightly cooler than late 20th century temperatures, we still have an MWP plateau that lasted for a few centuries within a few tenths of a degree of the peak modern warmth to date. Rather than try to downplay this or write it out of the climate history altogether, why not simply accept it and try to make the case that the 20th century warming is different because its suspected cause is something that won't reverse itself, which means that it will continue? Why not also point out that since what caused the MWP isn't fully understood, there's every reason to expect that it could reoccur - and that the combined effect of increased CO2 plus whatever naturally caused the MWP would be severe? You might be less able to make a case that we're only a few years away from a "point of no return" but nobody believes that and it's a risky argument anyway - when those few years pass but the point of no return doesn't, it will simply fuel more skepticism. There are a lot of skeptics who would be more open minded about AGW if it weren't for some of the overstatements and misstatements made by the more zealous of AGW supporters, including the efforts to rewrite the climate history. The Hockey Stick has done the AGW proponents more harm than good - when you mess with the established history, you create skeptics of your theories as to the present and future.

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