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Comments 116401 to 116450:

116401. chris at 01:25 AM on 29 June 2010
        Astronomical cycles
        Ken Lambert at 23:50 PM on 28 June, 2010 Well yes Ken, that's the point. You chose to make a great deal out of an apparent slow down in sea level rise. My point is that one cannot make profound interpretations from a very short period of data. After all if you wish to assert that the apparent slow down is significant then you can't really choose to ignore an equivalent apparent speed-up in sea level rise. We don't know to what extent these apparent slow downs and rises are fully real (they’re certainly at least partly real; see below). Overall the data continue to be compatible with a continuing trend in sea level equivalent to a rise somewhat above 3 mm.yr-1. This is wrong: "...entirely incompatible with the steadily increasing imbalance proposed by CO2GHG theory. If by "CO2GHG theory" you mean the rather well-founded expectation that the earth surface temperature will rise under the influence of a radiative imbalance towards a new equilibrium temperature around which it will fluctuate as a result of natural variability (i.e. the theory of enhanced greenhouse forcing), there isn't anything necessarily incompatible with the observed sea level rise data. It would be a fundamental misunderstanding to think that there should be anything necessarily "steady" about the progression of manifestations of radiative imbalance particularly when assessed over short periods. One needs to consider: (i) measurement errors. These are smaller for sea level rise measurements than for ocean heat content (OHC) measures, but they are significant as is obvious from inspection of the data . This is always a good reason for preferring longer term trends over very short time periods. (ii) real short term variability. This is likely to be large [*]. And of course we know this from simple inspection of the data. Natural variability will enhance the apparent greenhouse-forced sea level rise during some periods (El Nino, solar cycle, reduced albedo), and during other periods suppress the apparent sea level rise (La Nina, solar cycle, enhanced albedo, volcanic activity). Overall this natural variability will more or less reduce to near-zero with respect to trends. Therefore if we wish to make profound interpretations about trends, we obviously choose to assess the progression of parameters over longish periods in which this variability is averaged out. [*] For example, the redistribution of ocean heat during El Ninos and La Ninas can have very large temporary effects on sea level. It’s not unheard of the have a short term (year or so) rise of 10-15 mm.yr-1 during strong El Ninos, and largish sea level decreases during La Ninas. It’s dumb to pretend that these effects don’t occur, or to ignore them when attempting fundamental interpretations about responses to radiative imbalances.
116402. Doug Bostrom at 01:02 AM on 29 June 2010
        Sea level rise is exaggerated
        Let me explain why you need to do the work or must instead pipe down, Daniel. Any bachelor degree graduate can ... The Donnely paper...is simply an utter joke. Scientists who after having found the time and inclination to review the data of climate scientists are utterly apalled at the conclusions drawn. Those words are what is known as the "Badge of Hubris." You have said you believe the work you're criticizing to be defective, you have said that "any bachelor degree graduate" can show why. You have spoken for a number of scientists you claim are appalled. The problem is, you've not yet earned your Badge of Hubris because you have not shown exactly what is wrong with the authors' conclusions. Where are their ranges of uncertainty incorrect, how did they calculate that incorrectly, for instance? "I doubt it" is not an argument that can earn you the Badge of Hubris. Your demand that I supply the detail required to make your argument earns a Badge of Comedy. You're the person flinging assertions, support 'em or pipe down. Simple enough, right?
116403. Riccardo at 00:39 AM on 29 June 2010
        What causes the tropospheric hot spot?
        Berényi Péter, I wrote "following that paper", so it's not my idea but the results shown there. Anyways the answer to your question I think is no, but it's not clear to me where it comes from. Explaining the band (their fig. 3a) of negative correlation in the southern ocean the paper says: "negative correlation of γ with Ts can be attributed to a combination of the thermally inertial ocean and quite strong variations in the annual cycle of temperature at the top of the troposphere (with relatively small variations in surface temperature)." In other words it appears to be due to the annual cycle and to the associated changes in atmospheric circulation. When talking about the so called tropical hot spot one usually refers to the multi-year trend of the anomaly, which is not the same as what is shown in Mokhov et al. paper.
116404. Alexandre at 00:29 AM on 29 June 2010
        Perth event tonight: public forum on climate change
        I'll definetely download it afterwards.
116405. SNRatio at 00:13 AM on 29 June 2010
        What causes the tropospheric hot spot?
        First, I wonder if not the enhanced spikes in tropospheric temps relative to surface temps during El Ninos (see e.g. http://www.woodfortrees.org/plot/uah/...) could be illustration of the short term phenomena in question. (Not "trends".) Second, the denialist position is logically flawed in this case, too. For what happens to GW if the hot spots don't get very hot? As carrot eater related, there are two feedbacks in operation, a positive WV and a negative LR. Nothing much happens with the positive vapor feedback, BUT the negative lapse rate feeback, which is quite significant in GW, becomes much weaker without hot spots. (It does by no means disappear, though.) SO, the net effect, everything else equal, will be that the same amount of forcing will produce MORE warming without hot spots. Consequently, unless balanced by other effects, data speaking against hot spots are arguments for higher sensitivity.
116406. Ken Lambert at 23:50 PM on 28 June 2010
        Astronomical cycles
        Chris #100 I have not had time to go back to the prior sea level discussion, being away for a few days. It should be noted however that the very fact that there was an 'apparent' slowdown of the rise in the 2006-2008 period observed by Jason, followed by an impossible 6.5 mm/year to date; does indicate an unexplained variability in either the sea level or the Jason measurement. We are talking global sea level rise jumping from around 2mm to 6.5mm per year. This is a huge burst of heat equivalent; entirely incompatible with the steadily increasing imbalance proposed by CO2GHG theory. It would imply a thermal expansion rise of 3-4mm/year which is equivalent of about 280E20 Joules/year which is double Dr Trenberth's 145E20 Joules /year 'observed' by his 0.9W/sq.m TOA imbalance. Explaining this a noisy data might be credible if it applied to a part of the biosphere where the sum of the other parts even themselves out; but it is scarcely credible globally; for the whole of the planet.
116407. carrot eater at 23:49 PM on 28 June 2010
        What causes the tropospheric hot spot?
        Humanity Rules, You are all twisted up here. Nobody is talking about "short term trends associated with AGW". That doesn't even have meaning. We're talking about the short term variability, related to El Nino, La Nina, etc. Compare some satellite and surface records. You'll see, for example, the El Nino peak of 1998 is more exaggerated in the satellite records than it is in the surface records. That's the sort of thing being discussed here. Or, for a more careful analysis, just look at the linked papers. Remember, the 'hot spot' is not unique to greenhouse gases. It should exist, no matter what caused the surface to be warmer - including internal variability like ENSO.
116408. Jim Eager at 23:32 PM on 28 June 2010
        Perth event tonight: public forum on climate change
        Chris, unfortunately we're stuck with the fossil fuel energy source we have until we can build it's replacement, which means for the time being we have to burn fossil fuels to build that replacement. The more rapidly we build that replacement the sooner we can ratchet down using those fossil fuels. This is actually a very powerful argument in countering those who seek to delay taking action to construct a new energy infrastructure: if we wait until after peak oil it will 1) cost more, 2) we risk not having enough fossil fuel to build it in time, and 3) we will shift to coal, which insures that we will have less time.
116409. HumanityRules at 23:27 PM on 28 June 2010
        September 2010 Arctic Ice Extent Handicapping Via ARCUS
        SEARCH seems proud of the headlines it can generate.
116410. HumanityRules at 23:22 PM on 28 June 2010
        September 2010 Arctic Ice Extent Handicapping Via ARCUS
        58 chris this seems a little unfair. SEARCH is organised by mainstream arctic scientists and seems to garner participation from many mainstream arctic science groups. If it's little more than a game (no doubt generating headlines) then maybe these serious scientists shouldn't be participating. If we want less blogospheric hot air we should insist that scientist stick to what we (i.e. they) know.
116411. HumanityRules at 23:11 PM on 28 June 2010
        What causes the tropospheric hot spot?
        26 carrot eater It's not the failure to find a long term trend that I'm concerned about but how, in a highly variable data set, we can see the short term trends. Presumably these short term trends associated with AGW are also an order of magnitude below the variability unless the short term trend is an order of magnitude greater than the expected trend, which seems unlikely.
116412. KR at 23:08 PM on 28 June 2010
        Accelerating ice loss from Antarctica and Greenland
        I hope those 5000 D cells are rechargeables!
116413. Berényi Péter at 23:03 PM on 28 June 2010
        What causes the tropospheric hot spot?
        #27 Riccardo at 22:30 PM on 28 June, 2010 the lapse rate feedback is negative in the tropics but postive overall Let me understand. Are you saying with increasing surface temperatures overall rate of evaporation increases but the area where this happens decreases?
116414. Alexandre at 22:37 PM on 28 June 2010
        What causes the tropospheric hot spot?
        Thanks for the post, John. This was something I've been struggling to understand, too.
116415. Berényi Péter at 22:32 PM on 28 June 2010
        Ocean acidification
        #67 VoxRat at 20:34 PM on 28 June, 2010 ecosystems that have adjusted to current conditions over millions of years Global climate went crazy about 3 million years ago and the instability due to the general cooling trend is getting ever worse. Like a bad case of microphone whine. Current ecosystems are adjusted to this ever changing environment. It is part of the reason humans could afford to have an oversized brain in spite of its huge energy costs and cooling problems. If conditions are kept constant, there is no point whatsoever in being able to figure out what to do in case conditions would change. Keep in mind that all the endangered coral reefs of the world are substantially younger than twenty thousand years. Eighteen thousand years ago present day reef sites were on high ground, 120 m above sea level. That; and the arithmetic fact one hundred fifty times twenty thousand makes three million.
116416. Riccardo at 22:30 PM on 28 June 2010
        What causes the tropospheric hot spot?
        Berényi Péter, the hot spot is called tropospheric for a reason. And this is from the article you cite: "The correlation of γ with Ts is negative in the equatorial latitudes and midlatitudes over the oceans." Hence, following that paper the lapse rate feedback is negative in the tropics but postive overall, more so at the high latitudes.
116417. daniel at 22:26 PM on 28 June 2010
        Sea level rise is exaggerated
        Doug why don't you explain the detail required? I have provided all the detail nessecary. A short term trend of ~150 years, measured using direct measurement techniques at high resolution is compared to a general linear trend over ~550 years approximated using 10 paleo data points with clearly alot of uncertainty in each. There is no statistics to "undo" can you explain what you mean by that? I doubt only the conclusions section of the paper. 10 noisy data points do not adequately measure sea level trends at the 150 year time scale between 1300-1850 AD. Therefore it is invalid to conclude there has been a significant recent increase in seal level rise. As I mentioned in my previously deleted comment both you and peter have put words in my mouth by claiming I doubt the methods or error analysis of the Donnely paper or reffered to a "downturn" in recent sea level trends (good one pete). You're nit even listening to what I am saying. Which is a reflection on your credibility not mine.
116418. carrot eater at 21:56 PM on 28 June 2010
        What causes the tropospheric hot spot?
        HumanityRules, I think you might be confusing some matters. Maybe read the links put there, like this one http://pubs.giss.nasa.gov/docs/2005/2005_Santer_etal.pdf The surface record shows a lot of short-term variability, and that variability is even stronger in the troposphere. But given that large variability, and the quality of the observations, it is difficult to observe any long term trends.
116419. chris1204 at 21:52 PM on 28 June 2010
        Perth event tonight: public forum on climate change
        A question I'd love to put to Dr Oschmann relates to the carbon footprint involved in making the transition to a clean-energy future? Eg, we still have to power the machinery to mine the ore to build our wind turbines, generate CO2 while we make cement to build the infrastructure, etc. The answer might well turn out to be 'very small' which would be very welcome news. Notwithstanding my propensity to curmudgeonly contrarianism, I genuinely believe we need to reduce our reliance on fossil fuel would prefer to see us pumping much less CO2 into the environment. Best wishes for the evening.
        Response: Volker just emailed me a response to this question:

        “A recent comprehensive study (Almut Kirchner et al, “Blueprint Germany, A strategy for a climate-safe 2050”, Basel/Berlin 2009) argues that it is possible to reduce greenhouse gas emissions in Germany by 95 percent by 2050 (compared to 1990). This includes emissions to build the infrastructure necessary for the transition. An English version of the study can be found here."

116420. Berényi Péter at 21:36 PM on 28 June 2010
        What causes the tropospheric hot spot?
        The paper below observes a global 0.7% increase in lapse rate for a 1 K warming of surface. It means high above the ground the temperature anomaly should vanish (this surface is supposed to be at a much lower level above the poles than above low latitudes). They also say lapse rate is about 6.5 K/km at low latitudes and 4.5 K/km at the polar region, which is roughly consistent with the 0.7% figure (implies a 52.7 K difference in surface temperatures between poles and tropics, which is reasonable). How is it consistent with your statement ˇ"When the surface warms, there's more evaporation and more moisture in the air. This decreases the lapse rate - there's less cooling aloft. This means warming aloft is greater than warming at the surface. This amplified trend is the hot spot"? A detailed explanation would be welcome. Izvestiya Atmospheric and Oceanic Physics Volume 42, Number 4 / July, 2006, pp. 430-438 DOI: 10.1134/S0001433806040037 Tropospheric lapse rate and its relation to surface temperature from reanalysis data I. I. Mokhov and M. G. Akperov
116421. Byron Smith at 21:25 PM on 28 June 2010
        Perth event tonight: public forum on climate change
        Sounds like a good event. I hope the distinction between the science and the policy is made clear many times throughout the night. I fear that much of the angst about the science is really angst about policy options and people assume they are identical (i.e. if you accept the science, then there is only one policy option).
116422. Tenney Naumer at 21:25 PM on 28 June 2010
        Perth event tonight: public forum on climate change
        Best wishes for a successful discussion!
116423. HumanityRules at 21:08 PM on 28 June 2010
        What causes the tropospheric hot spot?
        John, There are a couple of points in your article that I'd like considered together because they are causing me some concern. 1) "the hot spot is well observed over short timescales". (I assume you mean the trend here not just the fact the hot spot exists) 2) "the short-term variability is nearly an order of magnitude greater than the long-term trend" I wonder to what extent you can be confident of the first fact given the existence of the second. How can we be sure that the short term trend is not just a happen-chance product of this natural variability? In many other aspects of climate it seems appropriate to be wary of short term trends for this very reason.
        Response: Short-term trends are totally due to internal variability. Eg - El Nino. So what we observe is the surface temperature ups and downs due to El Nino are magnified in the tropical troposphere.
116424. VoxRat at 20:34 PM on 28 June 2010
        Ocean acidification
        Arkadiusz Semczyszak #65 "“... a rapid recovery of coral reefs in areas of Indonesia, following the tsunami ... [2004 -2009]” Because some ecosystems can recover rapidly from some kinds of damage is not much of a case that a global acidification of the oceans is nothing to worry about. "As was the myth about the current rapid [change] of abnormal pH" What "myth" is that, exactly? "I recommend: http://omniclimate.wordpress.com/2009/02/04/a-shell-game-behind-ocean-acidification/ " Yes. I think we all agree that there have been times in the past when atmospheric [CO2] (and presumably ocean-surface acidity) were considerably higher. And we all agree that life can survive even under the extreme conditions of deep ocean volcanic vents. No one is saying CO2-induced acidification (or temperature rise, or anything else) is going to sterilize the planet. The point is: what happens when you abruptly change critical parameters (like pH, Omega-arag, and temperature) to ecosystems that have adjusted to current conditions over millions of years? I'm not so confident, as you appear to be, that the answer is "nothing much".
116425. Arkadiusz Semczyszak at 19:35 PM on 28 June 2010
        Ocean acidification
        "... growth ..." - of course not pH but change of pH
116426. Megan Evans at 19:03 PM on 28 June 2010
        Perth event tonight: public forum on climate change
        Sounds great! And also great that it's being recorded.
116427. Arkadiusz Semczyszak at 19:02 PM on 28 June 2010
        Ocean acidification
        @VoxRat "... a century or two ...” - you must compared with: “... a rapid recovery of coral reefs in areas of Indonesia, following the tsunami ... [2004 -2009]” As was the myth about the current rapid growth of abnormal pH, I recommend: http://omniclimate.wordpress.com/2009/02/04/a-shell-game-behind-ocean-acidification/
116428. tobyjoyce at 18:37 PM on 28 June 2010
        September 2010 Arctic Ice Extent Handicapping Via ARCUS
        Excellent Professor David Barber lecture on the current state of the Arctic Ice. Forward the video to 12:00 to skip the intros. Dr. David Barber
116429. John Bruno at 17:53 PM on 28 June 2010
        Perth event tonight: public forum on climate change
        wonderful. wish I could be there. thanks to whomever organized this.
116430. omnologos at 17:12 PM on 28 June 2010
        How many climate scientists are climate skeptics?
        doug_bostrom (#120): Revkin writes "For starters, one aspect of such efforts that I find troubling is the definition of categories...". And that's "for starters" 8-) In one of the comments at DotEarth, Revkin also links to Weart's comment #12 in this thread. Have a look. Finally, Revkin points to Keith Kloor's blog, that opens with "Judith Curry identifies what she considers to be “the big flaw” in the PNAS paper". And what have you been reading at RealClimate? How about this: "we note that once the categorization goes beyond a self-declared policy position, one is on very thin ice because the danger of ‘guilt by association’. For instance, one of us (Eric) feels more strongly that some of Prall’s classifications in his dataset cross a line" I say, even the guys at RealClimate could see the "methodological issues" with the PNAS paper, and felt free to talk openly about those. Where's instead the evidence that, in this circumstance, Skeptical Science has not "credulously pushed any news that might further its case"?
116431. JMurphy at 17:08 PM on 28 June 2010
        Why does Anthony Watts drive an electric car?
        philc wrote : "Thanks y'all for turning a marginal, but attractive(I hate bills) investment into one that is delivering around 6.5% and rising for the next 20 years." And yet the so-called skeptics reckon we are going to have to go back to the Stone Age and wear sack-cloths if we want to do anything to restrict the use of Carbon ? What you called the 'great AGW scare' seems more like the great AGW benefit (a benefit to alleviate a problem) to me. A great advertisement for doing the right thing : well done.
116432. Doug Bostrom at 12:48 PM on 28 June 2010
        Why does Anthony Watts drive an electric car?
        Philc, if you've not done it already, be sure to check on solar domestic hot water. Great bang for the buck. Works for me here in Seattle, worst-case scenario second only to Anchorage for U.S. cities and appears set to pay for itself before my 13 year old graduates from college even though I did not bother with any taxation juju. For some reason, here in the U.S. this is a big surprise...
116433. CBW at 12:40 PM on 28 June 2010
        What causes the tropospheric hot spot?
        It is interesting that the skeptics are so eager to misinterpret Figure 1 that they miss the real GHG signal that it clearly identifies--tropospheric warming combined with stratospheric cooling--which none of the other forcings could possibly produce.* How do they explain the fact that exactly that signature has been observed? *Except, in the figure, ozone, which I've been under the impression *is* a GHG.
116434. johnd at 10:46 AM on 28 June 2010
        What causes the tropospheric hot spot?
        carrot eater at 10:25 AM, it was along the various longitudes I meant. Both the models and the observations should vary somewhat given the different surface conditions and hence perhaps give better understanding to what is expected, and what does or does not actually occur. As for the latitude cross section, I would have thought that there would have been some bias in the model given the quite significant difference in the observed northern and southern hemisphere temperatures.
116435. philc at 10:39 AM on 28 June 2010
        Why does Anthony Watts drive an electric car?
        I'm a bit of a skeptic, but that didn't stop me from installing a 5.6 kw solar panel array. Mainly it seemed like a pretty bullet proof investment given the great likelihood of ongoing increases in electricity rates, and I hate bills. But thanks to the great AGW scare it suddenly became an even better investment when the guvmint decided to subsidize its installation and allow me to roughly double the rate of return by selling renewable energy credits. Thanks y'all for turning a marginal, but attractive(I hate bills) investment into one that is delivering around 6.5% and rising for the next 20 years.
116436. carrot eater at 10:25 AM on 28 June 2010
        What causes the tropospheric hot spot?
        19, johnd The figures above are model results, not observation, but the x-axes are latitude, which is what you seem to want. For observation, there are different sources; the last article here linked to one that has charts broken down by NH, tropics, SH. http://camels.metoffice.gov.uk/quarc/Sherwood08_JClimate.pdf
116437. Bern at 10:12 AM on 28 June 2010
        What causes the tropospheric hot spot?
        papertiger @ 18: Who's refusing to understand it's importance? That is, after all, the entire point of the post. Short term variability often masks subtle long-term shifts, and this hot spot is no different. Look at this post for an example of the effect, where annual variation in CO2 levels is quite large, although over longer periods the rising trend dominates. I get the impression that you regard a long-term shift to be insignificant if it's less than the short-term variability in the system? If so, then I'm sure you wont mind terribly if the average temperature in your neighbourhood increases by 10ºC or so, as that's still less than daily variability...
116438. johnd at 09:39 AM on 28 June 2010
        What causes the tropospheric hot spot?
        The depiction of the hot spot I assume is the average of data collected around the full circumference of the globe. Is there any depiction of how the hot spot varies, or should vary across the various regions of vastly different surface conditions?
116439. Doug Bostrom at 08:58 AM on 28 June 2010
        IPCC were wrong about Amazon rainforests
        OT but I should add, where I live "we" are the government and are too ignorant and shortsighted to run our affairs properly and meanwhile "we" tell businesses what they should sell us by buying their products. The hysterical whining and finger-poiting over the BP cost-cutting fiasco here makes me puke; we're the people insisting they sell us oil, we're the people who are too complacent to get educated, to vote. Talk about "look in the mirror." Ridiculous.
116440. Doug Bostrom at 08:52 AM on 28 June 2010
        IPCC were wrong about Amazon rainforests
        BP it seems we're in rare conjunction on the insult being delivered to the Amazon forest region. And I agree, the philosophy of biofuels is substantially porous in all directions. Where we diverge is the point of th IPCC report, which calls our attention to another folly on a massive scale, also laid at the feet of anachronisms. A scare? No more so than if I were to drop an anchor off the side of a boat with my feet standing in a loop of anchor chain and then, knowing this, not hop aside. More scary drowning that not. I've almost drowned twice, it was upsetting but the long-lasting regret has been reviewing how I put myself in the position of confronting breathing water when a little common sense would have made the exercise unnecessary.
116441. Berényi Péter at 08:20 AM on 28 June 2010
        IPCC were wrong about Amazon rainforests
        #19 doug_bostrom at 07:07 AM on 28 June, 2010 We're already the equivalent of an existentially threatening disaster In Amazonica, yes. Not "we", neither "the people", but irresponsible government and business practices. Including the biofuel craziness promoted by the AGW scare. The bottom line is that neither AGW nor CO₂ has anything to do with the ongoing deforestation in the Amazon basin, therefore including it in the IPCC report has no point other than to provide some absolution for those who need it. It is imperative to keep in touch with reality. the encyclopedia of the earth Deforestation in Amazonia Lead Author: Philip M. Fearnside Last Updated: March 30, 2007 See also: Terra Preta de Indio by Johannes Lehmann
116442. johnd at 08:12 AM on 28 June 2010
        IPCC were wrong about Amazon rainforests
        Berényi Péter at 07:00 AM, thanks for posting the link to the Acta Amazonica paper, I found it very interesting, not only for the subject under discussion, but how it relates to events in other parts of the world. Firstly, in Australia the years 1925 to 1930 saw widespread drought and below average rains across much of Australia, as did the years 1911 to 1916. In fact dry conditions across much of Australia were a fact of life for the entire first half of the 1900's with wetter conditions becoming more frequent post WW2. Anecdotal evidence is that the 1800's were also more prone to below average rains and droughts similar to the early 1900's. Secondly, the reference to the three prominent 'chimney' regions of convective upwelling, South America, Africa and the Maritime Continent is also of interest. Research in recent years has identified the IOD, the Indian Ocean Dipole, and this ties together the weather and climatic conditions of all those regions bounding the IO, Africa, India, Indonesia and Australia. It appears the the IOD has it's own cycles that at times, at least for Australia, either complements or offsets some of the ENSO effects. Droughts in Indonesia seem to correlate with droughts in Australia, with the major recent forest fires in Indonesia, 1982 and 1998 coinciding with dry conditions over much of Australia as well as those other dry periods in the Amazon basin as indicated by you. However, having said that, there is more often than not drought conditions somewhere in Australia, and perhaps the same might apply to other large areas such as South America and Africa.
116443. scaddenp at 07:59 AM on 28 June 2010
        Astronomical cycles
        philc - I dont believe you understand how parameterisation is done in GCMs. faq II for even more detail. In particular, I object that the "adjustable parameters" in GCM can be tuned in the way you say. Lets say that I use fundamental physics to create full model of process. It can be used over entire range of observable data. However, it might be also impossible to use in full form from computation limits in GCM or because if scale. You can however replace with parameterized model that is easy to calculate but which you can nonetheless verify works over full range. I suggest further discussion goes in "are models reliable" rather than here.
        Moderator Response: scaddenp's suggestion that further discussion happen on the Models are unreliable thread is a good one. So please do.
116444. Doug Bostrom at 07:36 AM on 28 June 2010
        IPCC were wrong about Amazon rainforests
        When the IPCC relies, as it has done far too often, on WWF and Greenpeace propaganda pieces, and newspaper articles, and the like... Willis if you quantify that assertion you'll be moving closer to joining the realist school of critique, moving away from applying your brush to impressionist strokes like that one. What are the statistics? If this were trivial as you claim ... then why does it get its own page on this very site? Good question. Why have journalists following Paris Hilton caused forests of pulp trees to fall when she's unarguably so inconsequential? The topic of the Amazon non-scandal appears here because all the overblown hype on this issue has left the public confused about what actual relevance this story had, which turns out to be little indeed. Finally, in addition to the IPCC question, the science is at issue as well. I have yet to see anyone link to a peer-reviewed article showing any evidence that 40% of the Amazon is at risk due to reduced rainfall due to warming ... Thank you for affording me the opportunity once again to quote the authority on the subject, Nepstad, whose work this vapid brouhaha was all about: In sum, the IPCC statement on the Amazon was correct. The report that is cited in support of the IPCC statement (Rowell and Moore 2000) omitted some citations in support of the 40% value statement. Senior Scientist Daniel Nepstad endorses the correctness of the IPCC’s (AR4) statement on Amazon forest susceptibility to rainfall reduction ...particularly when the Amazonian rainfall has not reduced during the last century of overall warming. As you well know even though you are sitting behind the easel of an impressionist, the subject whose portrait you are interpreting did not refer to past times. Here's what the subject did say: Up to 40% of the Amazonian forests could react drastically to even a slight reduction in precipitation; this means that the tropical vegetation, hydrology and climate system in South America could change very rapidly to another steady state, not necessarily producing gradual changes between the current and the future situation.
116445. philc at 07:35 AM on 28 June 2010
        Astronomical cycles
        Skeptical Science-Scafetta Enough already. It's elementary math and statistics that fitting a function to the data is only valid for the extent of the data. The fitted curve cannot be used to extrapolate future values. A good example are some of the IPCC graphs attempting to estimate future values of the temperature, depending on various emissions scenarios. In order to fit the 'curve" some of the emissions scenarios imply that temperatures in the past would be a hundred or more degrees below 0. For scientific usage, fitting a curve might show that the data has some periodic function in it, prompting a search for possible mechanisms, or it might give some insight into possible mechanisms to investigate. That, despite some of the exaggerated claims, is the whole point of the Scaffeta paper. There are apparent periodicities in the temperature data which coincide with periodicities in various solar, lunar, and planetary orbits. That suggests there might be a causative relationship that should be investigated. Very similar to the idea that rising C02 levels, even though they follow the intial temperature rise, correlate to rising temperatures in a fashion and might be part of the cause of rising temperatures, rather than an effect of them. the same thinking applies to any paramaterized model(all the GCM models in use). As pointed out by many others, any model with adjustable parameters in it is one person's opinion about what is going on. It may be useful in suggesting areas for further study and data gathering, it may suggest further experiments, but the model itself is useless for prediction outside the range of data used to calibrate it. For a good example of a non-parametric model look into the photo electric effect. A nice, simple equation, from first principles, that gives valid results over a wide range.
116446. Willis Eschenbach at 07:19 AM on 28 June 2010
        IPCC were wrong about Amazon rainforests
        doug_bostrom at 23:39 PM on 27 June, 2010 >> ...Despite all your unusually pragmatic work at WUWT, here you are regressed to grinding on IPCC process minutia of no actual significance. >> Doug, thanks for your thoughts. This is not "process minutia". When the IPCC relies, as it has done far too often, on WWF and Greenpeace propaganda pieces, and newspaper articles, and the like, it shows that the IPCC is a political rather than a scientific organization. Since many people claim that "the science is in" and "the IPCC has spoken, no one can dissent" and the like, this is very important. If this were trivial as you claim ... then why does it get its own page on this very site? Finally, in addition to the IPCC question, the science is at issue as well. I have yet to see anyone link to a peer-reviewed article showing any evidence that 40% of the Amazon is at risk due to reduced rainfall due to warming ... particularly when the Amazonian rainfall has not reduced during the last century of overall warming.
116447. Doug Bostrom at 07:07 AM on 28 June 2010
        IPCC were wrong about Amazon rainforests
        Yeah, looking at the graph again was a nice example of "confirmation bias," I suppose. Once I looked at the rest of it I see routine boom and bust. Apparently there's concern that the forest's resiliency has been degraded due to thoughtless treatment by various people trying to scrape out a living in the region, also to keep the flow of hamburgers steady. GScholar "Amazon deforestation" for details. We're already the equivalent of an existentially threatening disaster.
116448. Berényi Péter at 07:00 AM on 28 June 2010
        IPCC were wrong about Amazon rainforests
        #16 doug_bostrom at 05:04 AM on 28 June, 2010 the 1998 drought appears to be visible in your graphs Somewhat. Assigned to 1997 by the method I have applied. 1992 appears to be worse. However, if you are interested in how a really severe drought looks like there, read this paper: Acta Amazonica Print version ISSN 0044-5967 Acta Amaz. vol.35 no.2 Manaus April/June 2005 doi: 10.1590/S0044-59672005000200013 The drought of the century in the Amazon Basin: an analysis of the regional variation of rainfall in South America in 1926 Williams at al. The rain forest has managed to survive, somehow. At least it has not turned into savanna. BTW the drought of 1912 was also severe.
116449. Doug Bostrom at 06:55 AM on 28 June 2010
        Accelerating ice loss from Antarctica and Greenland
        More on the Pine Island robot mission here, with plentiful nits to pick at. Here are more details of the robot itself and its operations. 5,000(!) D-size batteries sounds on the face of it a questionable choice for power but I suppose grad students had to do the changing. The sub was capable of fully autonomous operation tens of kilometers from the mother ship and -under- the ice. Truly remarkable.
116450. johnd at 06:54 AM on 28 June 2010
        IPCC were wrong about Amazon rainforests
        Berényi Péter at 04:43 AM, the precipitation graph doesn't seem to indicate any exceptional deviations that could account for 2 specific events mentioned in the lead post, namely "severely drought stressed in 1998" and "the intense 2005 drought". Would it be the definition of "drought"? In tropical areas a drought could be 3 months without significant rain which disappears in the records when the followup rains return the annual precipitation to near normal levels. Or would it be that the drought conditions were localised to certain parts of the basin? How much variation was there across all of the cells, and was there any groupings of cells that were significantly different to the overall average?

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