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Riccardo at 20:39 PM on 26 January 2010Peer reviewed impacts of global warming
It's highly misleading to point out that the ecosystem, in some form or another, survived even to huge mass extinctions. Shifting the point of view from humans to nature as a whole is like accepting an eventual self-caused extinction of the human race, or at least of its civilization (beware, i'm not saying it's going to happen, but it's a possible consequence of that kind of reasoning). While it will probably happen anyway in a more or less far future, i'd not be so self-destructive to accelerate our fate. -
Riccardo at 19:55 PM on 26 January 2010It hasn't warmed since 1998
michaelkourlas, temperature is not global warming, the trend in temperature is. And, as will be repeated over and over, short term trends has no meaning whatsoever, even just statistically. Look critically at the data shown, ask for the uncertainty in the determination of the trends, look at the determination coefficient (whre shown). And take care, making hypothesis is easy untill you confront them with the known science. Any claim need to be justified quantitatively, which i can't see in the link you posted. Remember, climate change has (don't know why) a strong emotional impact on people, both "alarmists" and "deniers". The most conservative choice is stick to an expert advice, from climatologists; it's the very same thing we all do in our daily lives. -
Riccardo at 19:30 PM on 26 January 2010We're coming out of the Little Ice Age
michaelkourlas, you can surely use just a few years to calculate a trend but you can not establish it this way; it would be just a mathematical exercise. Physics, and climate science as well, uses mathematics as a tool but they also give a meaning to the numbers. When the data points have a "noise" of about 0.2 °C and a trend of about 0.17 °C/decade even common sense should convince you that it makes no sense at all to use just 7 years to calculate a meaningful trend. If you really want to understand what is going on with our climate, it would be a good idea not to use "blind" google searches. You know, the internet is a great tool, but you can find almost anything you want. Given that we not always have the knowledge to state the credibility of a source by ourselves, an a priori reasoned choice is mandatory. Or anyone can fool you. -
Arkadiusz Semczyszak at 19:21 PM on 26 January 2010It's a 1500 year cycle
"Changes in solar activity do affect the planet's energy imbalance but over the last 50 years, the sun has showed a slight cooling trend." The fact is, however, that before the sun was at its highest activity of 8 thousand. years (max - XIX solar cycle) http://www.aanda.org/images/stories/highlight/vol471-1/7704Usos.gif. We also believe that the sun gives its energy through the ocean - with a delay caused by the cycles presented here (solar, LNC: influencing THC - AMO, PDO, EN(LN)SO, NAO, AO, etc.). We believe, that global, hypothetical most probable period of delay is c. half of the Gleissberg cycle. F.e: light cool twenty-first century may be the result of the extended time of local solar minimum weak, from the 60s twenty century (XX solar cycle). -
Arkadiusz Semczyszak at 19:19 PM on 26 January 2010It's a 1500 year cycle
"In contrast, current global warming is occuring in both hemispheres and particularly throughout the world's oceans, indicating a significant energy imbalance." The fact remains that in the natural cycle of climate change we are (were?), when the phase of growing - rising - warming in NH - which show modern statistical data ("For smoothing we use local linear regression ...") presented here: http://www.rni.helsinki.fi/research/info/sizer/fig2big.jpg. It’s not Cherry Picking. "Many palaeoclimate records from earth's North Atlantic region depict a millennial-scale oscillation of climate, which during the last glacial period was highlighted by Dansgaard-Oeschger events that regularly recurred at approximately 1,470-year intervals (Rahmstorf, 2003 )."(by Idso K. and C., 2006). "The 1500 year cycles, known as Dansgaard-Oeschger events, are localized to the northern hemisphere and accompanied with cooling in the southern hemisphere." NIPCC, skeptics, We draw attention to a hypothetical series of circa 4.2 thousand. years (3 x Bond Events). Impact is stronger here - and the SH is only (weaker) warming; and circa 6 thousand. years solar cycle. We propose the following scheme for research: warming causes an increase in water vapor content of atmosphere - K.E. Trenberth, J. Fasullo, L. Smith, 2005: Trends and variability in column-integrated atmospheric water vapor. Fig 11. in this paper: here - on the map - we see that the place of the strongest growth of evaporation are related with the strength and reach of the north of THC (vitally affecting the AMO and AO). We know that present not only evaporation but also the strongest warming - it’s in the Arctic. This results in increased emissions of CO2 from the Arctic Sea, but also warming of Tundra: "Lloyd and Taylor (1994) found that the relative sensitivity to temperature change is much greater for soils at LOW temperatures than for warmer soils. For example, in the absence of moisture limitations, an increase from 0 to 1 deg C would result in a 22% increase in respiration, while an increase from 25 to 26 deg C leads to a 5% increase.", "Thus, modest global change scenarios resulting in a 1 to 2 deg C increase in mean temperature would have the most significant effect on the 60 g C/m2 year respired by tundra. [... and in the tundra - c. 1 / 5 land area - where the temperature has risen the most - from 2 to 3 deg C; and soil detritus is a great weight - most of the accumulated 21,6 kg C x m -2 (average) ...] (http://www.biology.duke.edu/bio265/ajm21/intro.html). At present, oxidation occurs at the age of detritus of several thousand to 10. thousand years. The ratio of carbon isotopes 14/13/12C - so here is similar to the fossil carbon. We believe that the cyclicality of the climate (in this and the Millennium) have a decisive influence solar cycles - direct; and through its impact on the moon - an indirect (LNC-LNO). We recommend to discuss in particular, the work: - http://ansatte.hials.no/hy/tide/default.htm, - Lunar nodal tide effects on variability of sea level, temperature, and salinity in the Faroe-Shetland Channel and the Barents Sea (Yndestad H. at al., 2008); - The 18.6-year lunar nodal cycle and surface temperature variability in the northeast Pacific (McKinnell, SM , and WR Crawford; 2007 ), - The impacts of the Luni-Solar oscillation on the Arctic oscillation (Ramos da Silva, R. , and R. Avissar; 2005 ), - Trends and anomalies in sea-surface temperature, observed over the last 60 years, within the southeastern Bay of Biscay (Goikoetxea N.; 2009), - Solar Forcing of Changes in Atmospheric Circulation, Earth's Rotation Solar (Mazzarella A.; 2008). -
Marcus at 18:30 PM on 26 January 2010Peer reviewed impacts of global warming
We're not burning fossilized dinosaurs, RSVP, we mostly burn fossilized trees. As for the benefits of global warming in winter-time, what about the negative impacts during spring & summer? Excessive warming can create major shifts in the spring & summer rainfall on which our agriculture relies. Increased warming can also lead to increased senescence, which in effect means that crops will "grow old before their time", resulting in decreased biomass. Also, there are signs in the literature that increased CO2 levels pushes plant biomass from seed production towards vegetative biomass. These 3 factors could combine to substantially decrease the amount of edible biomass on the planet (well for humans at any rate). This doesn't just impact on humans directly, but also on the biomass of the livestock animals which eat vegetable matter. That seems a pretty poor substitute for warmer winters to me (especially when one considers the role of winter weather in recharging aquifers). As to the ability of past animals & plants to survive in warmer conditions-well isn't it funny how 99% of the animals that thrived then no longer seem to be with us? Also, whilst dinosaurs, conifers & ferns might have thrived in a warm CO2 rich atmosphere, the mammals & edible grasses-on which our modern agriculture depends-all evolved in a cooler low-CO2 environment. -
RSVP at 17:49 PM on 26 January 2010Peer reviewed impacts of global warming
As the snow blows sidewise in the darkness outside, I make my best effort to convince myself of the negative effects of global warming. As created, I am egotistic by nature, and what might be positive to me, could well be negative to someone else. There is also this aspect of degree. A little global warming might be generally beneficial, a lot on the other hand, catastrophic. As far as concerns for Nature, there was a time when life thrived on a very much warmer planet. Not sure why this is never mentioned on this site. Maybe there is some connection afterall between AGW and burning fossilized dinosaurs.Response: "there was a time when life thrived on a very much warmer planet. Not sure why this is never mentioned on this site"
This idea is explored when considering whether animals and plants can adapt to global warming. The reason why nature is at threat from current global warming is because the rate of current warming is so rapid (and expected to accelerate), we're heading into temperatures that most existing species have never experienced and species are already under threat from other human impacts. -
Tom Dayton at 16:53 PM on 26 January 2010We're coming out of the Little Ice Age
michaelkourlas wrote "maybe I'm making a mistake, but I thought that the black line was the IPCC trend." Michael, you are indeed making a mistake, as Riccardo tried to explain to you. The IPCC prediction is the entire gray area in that figure. The black line is merely the mean, which is merely the most probable point-by-point portion--the central tendency of the prediction, not the range of the prediction. The range is the gray area. Nobody, least of all the IPCC, expects the actual values to always fall exactly on the line. Nobody even expects the actual values to always fall within the gray area. Instead the expectation is that sometimes the actual values will be above the line and sometimes below the line, but on average they will fall more or less the same amount of time above as below the line, and almost all of the time they will fall within the gray area. When you pick out the most recent four years as being below the black line, you are conveniently ignoring the several periods before that being above the line. Oh, but then you could point to the previous couple years being below the line. But then you'd be ignoring the years before that being far above the line.... And so on. If you play that game all the way back to the start of the graph, you see that on average the actual values spend nearly as much time above as below the line, and always inside the gray area. There are formal, systematic ways of doing the above analysis. They were not invented for climatology. They have been used for many decades in many different fields of science and technology. They are being applied to climatology in exactly the same way. You can start to learn about them by reading Tamino's post "How Long?" -
barry1487 at 14:56 PM on 26 January 2010On the reliability of the U.S. Surface Temperature Record
Thanks for this post. At Deltoid I posted a few links to Watts commenting on requests for analysis of the good stations, including his advice that he'd do it when 75% of the USHCN stations were surveyed. http://scienceblogs.com/deltoid/2010/01/so_thats_why_surfacestationsor.php#comment-2226935 I was very intrigued to see what happened at WUWT after reading Menne et al, and not overly surprised that there has been nothing thus far - even though the denizens there make sure that anything interesting to them hits WUWT within a few hours of being put online. I hope there will be a post on Menne et al. It will provide a fine opportunity to pin Watts down on the analysis question. Hopefully some bright sparks will post something polite and on the money, that he will look dishonest if he wriggles. -
michaelkourlas at 13:52 PM on 26 January 2010It hasn't warmed since 1998
Look at this link for information on global warming stagnation since 2002: LINK The site is run by Ole Humlum, Professor of Physical Geography at the Department of Geosciences, University of Oslo. He says that "all five global temperature estimates presently show stagnation, at least since 2002. There has been no increase in global air temperature since 1998, which was affected by the oceanographic El Niño event. This does not exclude the possibility that global temperatures will begin to increase again later. On the other hand, it also remain a possibility that Earth just now is passing a temperature peak, and that global temperatures will begin to decrease within the coming 5-10 years. Only time will show which of these possibilities is the correct."
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michaelkourlas at 13:33 PM on 26 January 2010It hasn't warmed since 1998
In reply to the above ocean comment, doesn't the fact that measurements conflict depending on depth cast doubt on whether or not the oceans are warming or cooling?Response: No, it shows that the upper ocean exchanges heat with the deeper ocean, leading to more variability in the upper ocean but a steadier trend in the overall ocean. -
Marcus at 13:04 PM on 26 January 2010Peer reviewed impacts of global warming
Actually, on a bright note, CSIRO scientists recently found that the rise in temperature needed to melt the methane clathrates is actually *higher* than previously thought. Doesn't help us much with CO2-induced warming, but a sudden release of methane from the clathrates could have resulted in a mass extinction much like that at the Permian-Triassic boundary! -
J Bowers at 12:45 PM on 26 January 2010Peer reviewed impacts of global warming
"Response: While looking at your papers, I discovered AGW Observer has a page devoted to papers on methane emissions which I'll need to peruse when I get the chance (well, rediscovered as AGW Observer is in my blog reader)." Yes, it's an excellent resource. Go to the Index page for a wealth of resources. -
michaelkourlas at 12:40 PM on 26 January 2010We're coming out of the Little Ice Age
Also look here for the natural vs anthropogenic prediction information (http://www.appinsys.com/GlobalWarming/PredictionFromCycles.htm) -
Marcus at 12:38 PM on 26 January 2010Peer reviewed impacts of global warming
Oh, here are some papers which might be of value for the impacts page: There's this paper about reduced micro-nutrient uptake by plants in high CO2 environments. "Rising atmospheric CO2 and human nutrition: toward globally imbalanced plant stoichiometry?" -
trrll at 12:38 PM on 26 January 2010On the reliability of the U.S. Surface Temperature Record
Some of the comments seem to reflect a fundamental confusion between precision and accuracy. Precision is the reproducibility of measurement, whereas accuracy is how well the value corresponds to the real value. The use of temperature anomalies recognizes that it is possible for a measurement to be precise but not accurate. For example, a temperature station that is located close to an air conditioner will, on the average, read warmer than one that is located far from the air conditioner. Fortunately, to evaluate climate change, you don't need accurate measurement of absolute temperature, you only need to determine how the temperature has changed over time, by subtracting the average temperature to compute the temperature anomaly, any average bias is subtracted, allowing precise determination of how temperature change over time. So are Watts's photos of temperature stations next to air conditioners irrelevant? Well, not necessarily. Suppose the temperature station is at some point moved closer to the air conditioner. Then there might be an increase in the temperature anomaly that does not reflect an increase in the average temperature at that site. Now, it seems pretty improbably that this would happen frequently enough to affect the trend appreciably, but somebody who desperately wants to disbelieve in global warming will clutch at any straw. So how do you test whether poor siting of temperature measurement stations really is associated with a greater warming trend, which could possibly be due to increased exposure to environmental factors that increase the measured temperature? You compare the trend in the temperature anomalies of the well-sited stations to that of the poorly sited stations. And what is the result? The poorly sited stations slightly underestimate the warming trend, rather than overestimating it. This pretty conclusively disposes of the bad siting hypothesis for the warming trend. I'd have to agree that it is a bit suspicious that Watt and colleagues have not reached, and reported, this conclusion themselves. It is hard not to suspect that they got the same results and chose not to report it because it didn't fit their hypothesis. To be charitable, sometimes when people get results that are inconsistent with a pet hypothesis, they are emotionally incapable of accepting that fact, and fall into perseveration, collecting more and more data in the hopes that if they get enough data the numbers will turn around--a bit like a compulsive gambler riding a losing streak deeper and deeper into debt in the conviction that sooner or later his luck will turn. -
Marcus at 12:26 PM on 26 January 2010Peer reviewed impacts of global warming
Peter, how much easier will it to be to get people that education if they're not dirt poor? Over-reliance on non-renewable sources of energy has kept many nations deeply in debt to those nations who have large surpluses of those resources-& so the cycle continues. I'm not suggesting its the only cause of poverty, but imagine how much more money they'd have to spend on health & education if they didn't have to spend billions per year-to foreign nations-on enough fossil fuels to keep vehicles running & the lights running. -
michaelkourlas at 12:16 PM on 26 January 2010We're coming out of the Little Ice Age
This is a good site for examining IPCC predictions and their failures. -
michaelkourlas at 12:14 PM on 26 January 2010We're coming out of the Little Ice Age
One can establish a trend from just a few years. The question is whether or not that trend is enough to justify spending large amounts of money and devastating certain economic sectors in the name of 'saving humanity'. I don't think 30 years of data, 10 of which show a decline in temperature, is sufficient for this. As for the IPCC predictions, maybe I'm making a mistake, but I thought that the black line was the IPCC trend, and the blue and red lines showing temperature have deviated from that line since 2005. That's at least 1/6th of the 30 year trend off course. -
Tom Dayton at 11:53 AM on 26 January 2010On the reliability of the U.S. Surface Temperature Record
yocta, the author (cce) of that site is working on putting it up on a different server, he told me a week or two ago. Thanks for finding that archived version of his slide presentation--I didn't know it existed. You could send cce an encouraging e-mail (his address is at the site you pointed to). -
mspelto at 11:21 AM on 26 January 2010Peer reviewed impacts of global warming
In terms of glacier melting you have to include the negatives of sea level rise , which also occurs due to thermal expansion. Glacier melt also impacts hydropower, note many specific glaciers such as Zongo GlacierResponse: Thanks, Vermeer 2009 on glaciers contributing to sea level rise is a worthy addition to the Impacts Page. Considering I'd already blogged about Vermeer 2009, you'd have thought I'd already included it (if I was more organised, I would've).
Re Pelto 2008, the abstract doesn't mention hydropower and unfortunately the full paper is hidden behind a paywall. -
stevecarsonr at 11:14 AM on 26 January 2010The chaos of confusing the concepts
Jacob Bock Axelsen: I'm definitely a novice on chaos so I need to keep asking questions to make sure I've understood your points correctly. So please don't think I'm trying to be argumentative as I press on again - it's the way I learn... (And I'll take a look at the Lorenz paper you provided but it will take a while and everyone will have moved on by the time I have digested it) 1. You said: "If you want to establish chaos you need to prove extreme sensitivity to initial conditions. It is virtually impossible without computer modelling and non-linear mathematics.." I'm throwing in the idea that climate *may* be chaotic to find out how well *your* original claim stands up. Of course I'm very glad that you posted the article because it is a subject that needs discussion, and therefore refreshing to find it here. But you claimed "climate is not chaotic". I'm asking you to really demonstrate it, or justify how your article demonstrated it. I'm certain that I can't *prove* that climate is chaotic. So to turn it around, to you the poster, can you actually establish that climate is not chaotic without the same burden? 2. Back to one of my first questions because I am very interested in knowing the answer.. My second question from 08:35 AM on 23 January about the fact that the poles will be colder than the equator, that there will still be seasons etc - is it true that this *doesn't* demonstrate that climate is NOT chaotic? It's just that I see arguments along these lines quite often (they seem so flawed as a demonstration of non-chaotic behavior that I think maybe there's something I don't understand). 3. You said: "Finally, the ice core record shows no signs of CO2 and CH4 leading to major chaos despite huge outgassings etc." Again maybe I just don't get chaos.. What is "major chaos" and what would one see? To me - if climate was chaotic I would expect to see ice ages, interglacials etc, like we have seen, but that their appearance, timing, coldness/hotness etc was "sensitive to initial conditions" - and therefore unpredictable. I noticed with your original 20th century temperature graph that you said "The climate is definitely non-linear, but also not chaotic in this plot." How can you tell? What is it that I don't understand about chaos? Can you pick it up by eye or did you apply a mathematical formula to it? -
luminous beauty at 11:09 AM on 26 January 2010On the reliability of the U.S. Surface Temperature Record
jpark, Compare what D'Aleo and Smith assert to what NOAA actually says about their Global Surface Network: http://gosic.org/gcos/GCOS-dev.htm -
J Bowers at 10:53 AM on 26 January 2010On the reliability of the U.S. Surface Temperature Record
Re: jpark at 09:06 AM on 24 January, 2010 "I read this "Why Hasn't Earth Warmed as Much as Expected? New Report on Climate Change Explores the Reasons" from Science Daily. I think you can understand my layman's puzzlement. http://www.sciencedaily.com/releases/2010/01/100119112050.htm " ------------------------------------------------------- Have a read of Ari Jokimäki's comments on Schwartz et al, over at AGW Observer: http://agwobserver.wordpress.com/2010/01/24/comments-on-schwartz-et-al-2010/ -
Daved Green at 10:51 AM on 26 January 2010The chaos of confusing the concepts
I think chaos doesnt really exist , its just that we are unable to see the reasons for events because they are either so complicated or spread over such long time scales that we cant see the patterns or get enough information to so what going to happen next . -
Gaz at 10:43 AM on 26 January 2010On the reliability of the U.S. Surface Temperature Record
Kforestcat: "..and then divide the current temp with the mean to get the anomaly." Maybe when you unjustifiably fire your next PhD you could ask them to explain the difference between subtraction and division before they leave. -
dhogaza at 10:43 AM on 26 January 2010On the reliability of the U.S. Surface Temperature Record
Jpark: Among other things D'Aleo doesn't know the difference between temp anomalies and absolute temperatures. He also doesn't know who is responsible for choosing the stations in the CLIMAT data set (hint: it's not the researchers who use the data to create GISTEMP, HadCRUT, etc). That's enough to skewer D'Aleo, not worth wasting any more time on him. As far as his "computer expert" EM Smith goes, he converts all the temperature data to INTEGERS before doing any analysis. Think about that. It's beyond bone-headed. -
yocta at 10:16 AM on 26 January 2010On the reliability of the U.S. Surface Temperature Record
jpark if you have time watch this: The Global Warming Debate A Layman’s Guide to the Science and Controversy A layman decided to search evidence from both sides. It has a good history of the scientific discoveries of global warming as well as how the media and skeptics first dealt with it. He details how in his experience he has found similarities with today's skeptics with how they dealt with acid rain and the ozone hole and misrepresent information. He includes all references to the papers and evidence he found. PS to John. The link you have under "resources" for the HTML version of this no longer (works...http://cce.890m.com/) Which is a pity as it was a really good site. -
shawnhet at 10:01 AM on 26 January 2010The chaos of confusing the concepts
Jacob:"Personally, I am skeptical that your proposed THC-mechanism is chaotic because I see no possibility of heat being trapped in a truly fluid fashion. Would THC shut down lead to Arctic freezing to start with?" I think you may have missed the point of steve's hypothetical. It is not necessary to "trap" heat at any point in order to get chaotic behavior at least in theory. Steve Carson is suggesting a situation where albedo has the potential to vary more in different places than in others. The polar regions for instance have the potential for wide variation in albedo while the tropical regions have fairly small potential for variation. Thus, it follows that simply moving more heat to polar regions away from tropical areas will have a greater warming effect on the globe as a whole than something that does the opposite. Does the climate system have the capacity to move sufficient heat to make its overall behavior chaotic? Beats me, but there is no need for heat to be "trapped" anywhere for it to be present. Cheers, :) -
Riccardo at 09:46 AM on 26 January 2010On the reliability of the U.S. Surface Temperature Record
jpark, not much. It's the same old cry from D'Aleo who says a lot of things but does not prove any, and in the meanwhile makes a whole lot of gross mistakes. One should really need to hear those craps to blindly accept them acritically. -
jpark at 09:28 AM on 26 January 2010On the reliability of the U.S. Surface Temperature Record
And is this helpful too? -
jpark at 09:25 AM on 26 January 2010On the reliability of the U.S. Surface Temperature Record
dhogaza..great answer, I like that. -
shawnhet at 09:15 AM on 26 January 2010Peer reviewed impacts of global warming
Here are a couple of generally positive papers: Nemani, R.R., Keeling, C.D., Hashimoto, H., Jolly, W.M., Piper, S.C., Tucker, C.J., Myneni, R.B. and Running, S.W., 2003. Climate driven increases in global terrestrial net primary production from 1982 to 1999. Science. (June-06-2003). Zhou, L, Tucker, C.J., Kaufman, R.K., Slayback, D., Shabanov, N.V., and Myneni, R.B. Variations in northern vegetation activity inferred from satellite data of vegetation index during 1981 to 1999, J. Geophys. Res., 106 (D17):20069-20083. Cheers, :)Response: Thanks, have added these to the Impacts Page. -
Berényi Péter at 08:45 AM on 26 January 2010Peer reviewed impacts of global warming
Marcus at 23:28 PM on 25 January, 2010: "the fear is that our societies will not be able to adapt quickly enough to global warming [...] so mitigation is seen as our best bet" The best bet is education. Not education about global warming, just plain old education, spiritual, moral, mental & physical. Education of the poor, education of girls. An educated society can adapt quickly enough to almost anything. This is the most efficient use of scant resources. Everything else can wait.Response: I agree that education is crucial to society, especially education for the poor. However, human society is capable of tackling more than one issue at a time. Setting aside global warming until we solve education for the poor is hardly a practical response, particularly as every year of inaction only exacerbates the problem - which happens to impact poor nations the greatest (Mendelsohn 2006). -
Riccardo at 08:20 AM on 26 January 2010We're coming out of the Little Ice Age
michaelkourlas, if i got it right, 30 years are enough to establish a trend. If this is true, then the last 10 years are well inside the measured variability and cannot falsify the trend in any way. But, given that you think that fig. 1 in the link i posted before "shows the measurements not following the IPCC predictions" you problably can say almost anything you like. The numbers tell a different story, though. -
Jacob Bock Axelsen at 08:00 AM on 26 January 2010Peer reviewed impacts of global warming
Since Berényi Péter already mentioned Eugene Koonin and Biology Direct. I invite people to see how tough the peer review process really is (the reviews are directly attached to the article at the bottom of the webpage): http://www.biology-direct.com/content/2/1/32 This paper was four years in the making... -
mspelto at 07:06 AM on 26 January 2010The IPCC's 2035 prediction about Himalayan glaciers
Last year and this year I am authoring the section for the BAMS annual state of the climate on Glaciers and Ice Sheets. This report focuses primarily on climate during that given calendar year and is a great resource for understanding the details of annual climate around the world. Believe me the IPCC report is not a source of information. Since this report is due before the data is generally even reported to the WGMS, the glacier data comes directly from the researchers. Glacier runoff is the product of the area and melt rate of the glaciers. Smaller glacier areas reduce melt season glacier runoff. For most areas the melt season is also the dry season, so this is perfect. This is not the case for streams draining the south side of the Himalaya where the summer monsoon is both the wet season and the main melt season on those glaciers. Note Gangotri Glacier as an example. Note that given the debris cover soot will not matter to the lower section of this glacier, nor will it matter to the area above 5500 meters which is a perpetual accumulation zone, with soot being buried. Thus, soot impacts are limited to that narrow elevation range near the equilibrium line. As a glacier disappears it does not automatically change runoff, that depends on precipitation. It changes the timing. Thus, in the < a href=http://www.nichols.edu/departments/glacier/glacier.htm">Skagit River in Washington for example glacier retreat has caused a reduction in summer streamflow, but winter streamflow has increased due to more winter rain and melt events in the basin. The glaciers are reservoirs that naturally store water that melts during dry periods for most areas. That is the value and is increasingly being utilized for hydropower as for Gangotri Glacier above or many others -
Berényi Péter at 06:19 AM on 26 January 2010Skeptical Science now an iPhone app
doug_bostrom at 06:37 AM on 17 January, 2010: "Ah, the meme du jour [global averages [of specific humidity in upper troposphere] are not too important, according to Pielke], repeated everywhere just now. What does it have to do with what you were discussing?" doug, looking into the physics (yes, I am able to do that) what Pielke says may be right in an unexpected way. The "greenhouse effect" of water vapor is roughly proportional to the logarithm of specific humidity. It means that vapor, if distributed unevenly, lets more IR radiation through than the same amount with uniform density along each pressure level. In fact specific humidity in the mid to upper troposphere is known to fluctuate within wide margins. The bottom line is that trends in arithmetic means are less important than trends in statistical dispersion. This measure may even be safer to rate against alleged instrumental errors (you see, it has quite something to do with the present discussion). Is there such a study about historical radiosonde humidity data in the literature? -
michaelkourlas at 05:56 AM on 26 January 2010We're coming out of the Little Ice Age
I'm not trying to make predictions off of a 10 year trend. All I am saying is that 30 years, 10 years of which do not follow predicted trends, is not enough to establish that we are having a large effect on climate. In response to "the models did not predict the last 10 years...because they never attempted to predict them", the link you gave actually shows the measurements not following the IPCC predictions. -
michaelkourlas at 05:51 AM on 26 January 2010It's not bad
I feel that the positives vs. negatives are somewhat biased toward the negative side. For instance, on negative, it says decreased water levels three times, and specifies each individual area where the water supplies will decrease each time: * Decreasing human water supplies... (Solomon 2009) * Decreased water supply in the Colorado River Basin (McCabe 2007) * Decreasing water supply to the Murray-Darling Basin (Cai 2008) However, on positive, it only says: Improved agriculture in some high latitude regions (Mendelsohn 2006) It does not specify what countries or regions, which could inflate it to several points. Seeing as that has been done with the decreasing water supply, I think the same should be done for the positives.Response: This is solely because I'm referencing individual papers. I suggest you take a leaf out of Shawnhet's book and find some positive papers focusing on benefits in specific regions. -
Jacob Bock Axelsen at 05:49 AM on 26 January 2010The chaos of confusing the concepts
@stevecarsonr (I here use 'deterministic chaos' and 'chaos' interchangeably.) If you want to establish chaos you need to prove extreme sensitivity to initial conditions. It is virtually impossible without computer modelling and non-linear mathematics. I understand that you could imagine chaos 'in the error bars' of clouds and aerosol, but you need more advanced arguments than feedbacks. I could be my own devil's advocate by pointing to the surprising fact that all-negative feedbacks can be chaotic: http://arxiv.org/abs/0905.3672 - just to emphasize the necessity of proper mathematical modelling. Personally, I am skeptical that your proposed THC-mechanism is chaotic because I see no possibility of heat being trapped in a truly fluid fashion. Would THC shut down lead to Arctic freezing to start with? I have still not touched upon how to actually detect chaos, but one way is the Lorenz map: take the sequential period-maxima of your data (m1,m2,m3,m4,...) and plot the pairs ((m1,m2),(m2,m3),(m3,m4),...). If you have a predictable cycle, as non-linear as you like, you will get a cloud of points mostly tracing the diagonal (like for ice ages). Do it for a strange attractor and you could get some off-diagonal contour. Lorenz produced a 'teepee' and proved how to extract order from chaos(!): http://ams.allenpress.com/archive/1520-0469/37/8/pdf/i1520-0469-37-8-1685.pdf I note that you use turbulence and deterministic chaos somewhat interchangeably, which is a clear misunderstanding. In your boiling kettle any possible chaos in heat advection is destroyed by turbulence and vapour bubbles. Please visit the links I provided before for a much more precise picture of convection. In searching for origins of minor chaos one obvious candidate is El Niño's trapped equatorial surface waters. In 1998 roughly 10^21 J was transiently trapped in the atmosphere before it could leak to space. It is now understood to be almost entirely due to deterministic chaos in weather spilling over to the global energy budget. Again the Rayleigh number is useful: it is the wind that initially is chaotic because it has a high Rayleigh number. The best way to predict large-scale chaos is then to have El Niño and the Lorenz attractor in mind when hypothesizing about a much stronger mechanism. Finally, the ice core record shows no signs of CO2 and CH4 leading to major chaos despite huge outgassings etc. There were also varying aerosols, clouds and all other feedbacks throughout the period, so the record is a strong indication that we cannot expect spontaneous wild chaotic behavior of the future climate. Again, it is just my highly informal comments - not science. -
Vinny Burgoo at 05:37 AM on 26 January 2010Peer reviewed impacts of global warming
Thanks for your friendly response to my somewhat snarky comment. Alas, the description of the Evans et al. paper is still misleading. This isn't really your fault. The paper itself consistently misdescribed the area it studied as 'the UK'. What it actually predicted was that the range and severity of the disease will increase on the island of Great Britain. It didn't model the offshore islands or Northern Ireland. That's a minor point. More serious objections remain. I've already said that I don't think it's helpful or meaningful to include single, narrowly focused studies in isolation. You have replied that the tabulation is a work-in-progress. Fair enough. But if I had the time, I could probably find peer-reviewed studies contradicting most of the studies listed in your Negatives column. This wouldn't be easy. Climate research tends to concentrate on Negatives. (This isn't necessarily proof of systematic alarmist bias. People need prior information about possible negative impacts; positive impacts can be embraced without little or no prior planning.) But it's possible. You could then restock the right-hand column with more citations. I'd go a-hunting again. Then you. Then me. And so on. I'd do this not to prove that global warming is a good thing (you'd certainly win in the end) but to reinforce the point that lists of single studies don't prove anything. Back to the Evans et al. study. First the increased range. It's insignificant. Evans et al. predicted that phoma stem canker will newly colonize parts of eastern Scotland. A subsequent study of the same disease and its effects on the same crop in the same region (and once again misdescribing it as 'the UK') using the same model and by two of the same authors - Butterworth et al., 2009, below - predicted that the disease will have such mild effects in the newly colonized area that fungicides won't be necessary. So it's not a big deal. But your description implies that it is. Crop disease to increase its range! Help! Second, the real-world implications of all the Evans et al. predictions. The follow-up, Butterworth et al., predicted that yields of fungicide-treated oilseed rape will increase throughout 'the UK' (Great Britain). That is, despite increased opportunities for the disease, sensible management will result in a net Positive. See? Individual papers can be knocked down - sometimes by papers from the same authors using the same data, techniques and models. Even when done honestly, your tabulation has no hope of being helpful or meaningful. And I have to say that I don't think your intent *is* wholly honest. Else why the note about some of the Positives being tongue-in-cheek? And that hot/cold deaths reference: that also leaps off the screen ... But I've gone on long enough, so I won't get into that now. * Agriculture: Positives Increased oilseed rape yields throughout Great Britain _North–South divide: contrasting impacts of climate change on crop yields in Scotland and England_, Butterworth et al., 2009 http://rsif.royalsocietypublishing.org/content/7/42/123.fullResponse: I've removed Evans 2008 from the Impacts Page - Butterworth 2009 shows that the overall impact of global warming on crop disease is ambiguous. Thanks for the link to the additional paper.
I would be quite happy if you were to take the time to find more papers showing contrary results to papers currently listed. I appreciate the feedback you provided on forest growth and crop disease. It's not a competition to see who gets the biggest list but an effort to portray the state of the science.
The tongue in cheek remark was an artifact of the older version of the paper when I was referencing many media articles as my sources - originally, I was padding out the meagre positives column with entries like "Lots of work and money for lawyers" and "New extreme sport of glacier surfing". Once I got serious with only peer review sources, that comment was out-of-date and I've now removed it. -
Doug Bostrom at 05:36 AM on 26 January 2010Peer reviewed impacts of global warming
J Bowers: "Personally, I see why it's better to go with the peer reviewed literature, but I doubt too many are aware that non-peer reviewed literature was allowed anyway as set out in the IPCC's 'Appendix A to the Principles Governing IPCC Work' Annex 2." Further to that, considering all the grumbling about "suppression" of contra-mainstream findings, if the IPCC had not allowed material not passed through peer review I'm fairly sure we'd be listening now to endless complaints about IPCC censorship. Anyway, everybody participating in the next report will be more careful next time around. Once burnt, twice shy. -
J Bowers at 05:19 AM on 26 January 2010Peer reviewed impacts of global warming
A long-term association between global temperature and biodiversity, origination and extinction in the fossil record. Mayhew et al (2007) Articles from Proceedings of the Royal Society B: Biological Sciences http://ukpmc.ac.uk/articlerender.cgi?tool=pubmed&pubmedid=17956842 -
J Bowers at 05:15 AM on 26 January 2010Peer reviewed impacts of global warming
Saturation of the Southern Ocean CO2 Sink Due to Recent Climate Change Le Quéré et al, 2007 http://www.sciencemag.org/cgi/content/abstract/sci;316/5832/1735 Methane: Anomalies of methane in the atmosphere over the East Siberian shelf: Is there any sign of methane leakage from shallow shelf hydrates? – Shakhova et al. (2008) http://www.cosis.net/abstracts/EGU2008/01526/EGU2008-A-01526.pdf Escape of methane gas from the seabed along the West Spitsbergen continental margin – Westbrook et al. (2009) Abstract: http://www.agu.org/pubs/crossref/2009/2009GL039191.shtml http://sprint.clivar.org/soes/staff/ejr/Rohling-papers/2009-Westbrook%20et%20al%20JR211%20plumes%20GRL.pdfResponse: Many thanks, have added the two methane papers to a subsection of Arctic melt on the Impacts Page. While looking at your papers, I discovered AGW Observer has a page devoted to papers on methane emissions which I'll need to peruse when I get the chance (well, rediscovered as AGW Observer is in my blog reader). -
J Bowers at 05:00 AM on 26 January 2010Peer reviewed impacts of global warming
Personally, I see why it's better to go with the peer reviewed literature, but I doubt too many are aware that non-peer reviewed literature was allowed anyway as set out in the IPCC's 'Appendix A to the Principles Governing IPCC Work' Annex 2. Anyway, here's one concerning the detrimental effects of nitrogen deficit constraining CO2 uptake by plants: http://www.agu.org/pubs/crossref/2009/2009GL041009.shtml Wang et al. Nitrogen constraints on terrestrial carbon uptake: Implications for the global carbon-climate feedback. Geophysical Research Letters, 2009; 36 (24): L24403 DOI: ScienceDaily's take on the paper: "The authors considered the amount of nitrogen plants require to store additional carbon and found that a substantial deficit of nitrogen exists for plants in most areas of the world. They argue that most climate models that do not take into account nitrogen have overestimated carbon uptake and therefore underestimated predicted global warming." http://www.sciencedaily.com/releases/2010/01/100121164209.htm?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+sciencedaily+%28ScienceDaily%3A+Latest+Science+News%29 -
Jesús Rosino at 03:45 AM on 26 January 2010Peer reviewed impacts of global warming
John (inline comment in #32), Ok, thanks! I'll probably wait a week or so for the translation, just in case new comments contribute more relevant papers. -
rookie at 02:31 AM on 26 January 2010On the reliability of the U.S. Surface Temperature Record
My first post. Not sure if this will help, but here is a link to Thursday's NY Times article: http://www.nytimes.com/2010/01/22/science/earth/22warming.html?partner=rss&emc=rss The article, titled,"Past Decade Warmest on Record, NASA Data Shows," concludes that: "The NASA data released Thursday showed an upward temperature trend of about 0.36 degrees Fahrenheit (0.2 degrees Celsius) per decade over the past 30 years. Average global temperatures have risen by about 1.5 degrees Fahrenheit (0.8 degrees Celsius) since 1880." -
dhogaza at 02:31 AM on 26 January 2010On the reliability of the U.S. Surface Temperature Record
"I guess my instinct would be 'bad data=bad science'." All data is, to some extent, "bad", as there is no such thing as a perfect instrument. The question is whether or not a set of data is *useful* in the context of the task at hand. Making sense of imperfect data is very good science, indeed. -
RSVP at 02:09 AM on 26 January 2010Peer reviewed impacts of global warming
John, OK fine,... climate scientists acknowledge that a global temperature change is possible without man, and likely should happen at a slower rate than what we are seeing. Just out of curiousity, what triggers this change in nature? BUT... That question aside, as I was trying to point out, there seems to be two approaches to dealing with this problem: A) trying to stop global warming B) finding ways to adapt to it Theme B seems more relevant given that there currently are no guarantees that A is possible, again since if Nature wants to, it can change course without our consent.Response: "climate scientists acknowledge that a global temperature change is possible without man, and likely should happen at a slower rate than what we are seeing"
Actually, natural forcings on their own are showing a slight cooling effect over the last few decades (Meehl 2004).
As for the two approaches (mitigation or adaption), we need to be throwing our energies into both mitigation and adaption. This is because if we don't mitigate, future impacts will be even worse. And we need to prepare for adaption because we've already committed to a great deal of warming still "in the pipeline" (a topic I sorely need to write a post about which I will do as soon as I get the time).
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