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Global cooling: the new kid on the block

Posted on 4 March 2008 by John Cook

A new argument is hurtling up the Skeptic Leaderboard, leaving old stalwarts like mid-century cooling and water vapor in its wake. The argument is that global warming has reversed and we're now undergoing global cooling. No, it's not the old chestnut global warming stopped in 1998. The new contention is that global warming stopped in January 2007.

The argument originated from Anthony Watts who plotted data from 4 sources (HadCRUT, GISS, RSS and UAH), all of which show sharp cooling of around 0.6°C from January 2007 to January 2008. The most common interpretation around the blogosphere is that the long term global warming trend has reversed. Daily Tech goes so far as to say 2007 "wipes out a century of warming".

hadcrut-jan08
Figure 1: global temperature anomaly from HadCRUT (graph courtesy Anthony Watts).

The flaw in this interpretation is in drawing conclusions about long term climate change over a relatively short period of 13 months. Particularly when a large portion of that cooling occured over one month (January 2008). Only over a period of years to decades can you confidently discern climate trends. Otherwise, you run the danger of mistaking weather for climate.

Nevertheless, several important questions remain - what's causing this sudden cooling and is it the start of a long term trend?

Is the sun driving global cooling?

The general consensus among skeptic blogs is that diminished solar activity is the cause. The sun is currently at solar minimum - cycle 23 just ended and cycle 24 is having trouble kicking along. It's as cool as it gets in the solar cycle.

However, a temperature drop of 0.6°C would require a dramatic reduction in Total Solar Irradiance (TSI). According to theoretical calculations at Atmoz, TSI would need to fall to 1347.65 W/m2 to produce a global cooling of 0.6°C. In other words, 13 W/m2 less than current levels. This is ludicrously large considering the solar cycle varies only around 1.3 W/m2.

Alternatively, Camp 2007 adopts an empirical approach to calculate solar influence on global temperature. He determines the solar cycle contributes 0.18°C cooling to global temperatures as the sun moves from maximum to minimum. Note - this includes any influence due to cosmic rays as TSI closely correlates with the solar magnetic field which modulates cosmic radiation. Employing back of a napkin calculations, TSI would need to fall roughly 4.3 W/m2 to provide 0.6°C of cooling.

Either way, TSI needs to drop considerably to be considered the driver of 2007 cooling. So what has the sun been doing over the last few years?


Figure 2: TSI Composite and Sunspot Numbers (graph courtesy Greg Kopp).

Satellite measurements show no dramatic drop in TSI over the past several years. Instead, the solar cycle is following its usual 11 year cycle, flattening out as it reaches solar minimum. So if not the sun, what's causing the cooling?

La Niña - the likely culprit

Currently, the Pacific Ocean is in a La Niña phase. During La Niña, cold waters upwell to cool large areas of the equatorial Pacific Ocean. This has the effect of cooling the atmosphere. During the La Niña episode of 1999, global temperatures dropped around 0.5°C.

The Southern Oscillation Index (SOI) is a measure of La Niña. Positive SOI corresponds to a La Niña phase. In 2006, the Pacific Ocean was in El Niño phase (negative SOI). However, in late 2006, El Niño subsided and in mid 2007, crossed into La Niña phase. La Niña peaked around January 2008 and is the strongest La Niña since 1999. In the Eastern Pacific, sea-surface temperatures are about two degrees colder than normal over an area the size of the United States.


Figure 3: Southern Oscillation Index (graph courtesy bom.giv.au).

Future predictions for global cooling

The UK Met Office predict the cooling effect of La Niña will be slightly greater in 2008 than it was during 2007. According to NOAA’s Climate Prediction Center, the current La Niña episode is expected to start weakening in February 2008. The moral of the story - don't use short term weather patterns to draw conclusions about long term climate trends. My prediction is the current global cooling trend will reverse around mid-2008 when La Niña subsides. That's a bit vague though - feel free to go out on a limb and post a comment with your own prediction of the following months.

Meanwhile, solar cycle 24 is expected to crank up later this year so over the next 5 years, the global warming trend will accelerate as increasing solar activity adds to CO2 warming. So enjoy the cold while it lasts. Personally, I'm strongly considering a skiing holiday.

Update 13 March 2008: NASA GISS have updated the Land Ocean Temperature Index. February 2008 shows a global temperature increase of 0.14°C from January 2008. Not as much as John Cross predicted but more than I expected - I thought La Nina cooling might continue for at least a few more months. Probably a bit early to say La Nina cooling has reversed though - will be interesting to see March's figures.

UPDATE 9 April 2008: I've updated the monthly temperature with March's data at La Nina watch: March update (also busied up the graph with Southern Oscillation Index data).

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Comments 51 to 70 out of 70:

  1. Doesn't exist? At all? http://www.madsci.org/posts/archives/2001-08/998063731.En.r.html http://links.jstor.org/sici?sici=0021-8901(196606)3%3C87%3ADRITEO%3E2.0.CO%3B2-Y http://links.jstor.org/sici?sici=0021-8901(197512)12%3A3%3C781%3ADEITAK%3E2.0.CO%3B2-X http://www.sciencemag.org/cgi/content/abstract/172/3986/955 http://www.springerlink.com/content/d213435j6t82v118/ This one might be the most interesting found in that brief search: http://links.jstor.org/sici?sici=0022-541X(197207)36%3A3%3C733%3ALMODBC%3E2.0.CO%3B2-3 Birds might do fine even on high doses, so long as they don't have to mobilize the stored substance. If they do, then the concentration in sensitive tissues (which fat is not, being a storage deposit) skyrockets and soon kills them. It's not only about chemistry, it's also about physiology and environemental dynamics. As for everything happening in Nature, complexity comes in to play. It's easy to show a population of healthy birds fed large amounts of a toxic. All you have to do is make sure they have plenty to eat. The toxic stays in storage tissues. What happens in the real world is another story. This is just a few minutes of surfing. Note that I did not say that it should have been banned either. As for lead paint, sorry but this is what kids do. They put stuff in their mouths. Small chips will be swallowed. Inevitably. Other countries banned the nonsensical lead paint for toys and other children accessories as early as the first half of th 20th century. Interior paints soon followed. http://www.mindfully.org/Health/Lead-Industry-Public-Health.htm http://www.sciencemag.org/cgi/content/summary/298/5594/732
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  2. You don't have to apologize for your tone. There is nothing wrong with being opinionated, so long as you can still communicate, and your tone is a model of courtesy compared to freaks like BTN. To get back to the topic of skepticism, one question. When you discovered that the DDT was a joke in the chemistry department of your University, did you check in the biology department? About acid rain and China, I was serious. An airline pilot friend of mine was recently in Shanghai, where He was lodged in a tall hotel with exterior elevators. On a "good" weather day (i.e. no clouds, rain, fog to obstruct visibility) he lost sight of the ground completely at the 16th floor. That's essentially man made weather. They have to shoot instrument approaches there all the time, even in weather that would be VFR anywhere else in the world. So I repeat my question, would you like to live in a place like that? If not, how do you avoid the place where you live to become like that?
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  3. When I said BTN, I meant GMB (they need more variety in scrren names really).
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  4. Yes Phillippe, I actually did check with some Biology people some including one well known one hung on to the idea a lot longer but basically surrendered on it after a few more trials. It just happens that issue really bugs me because the ban did so much more harm both to humans and to the environment than DDT ever could. At the time I searched every professional publication on the subject and kept finding out the skeptics had the data right. So, assuming I was totally wrong I actually began tracking Rachel Carsons references, looking the people up calling or writting to them... lets not go there. I don't doubt the reality of acid rain, I do doubt that it was a catastrophy and I am mighty disgusted with the wide scale condemnation of US power generation and manufacturing at the time for Canada having a problem that was at least 99% self inflicted. Thanks anyway for being understanding, as I said we are all vulnerable where our prejudices are concerned and I've built a dandy on that issue. Your Shanghai story brings up a further point though, consequences of foolish environmental decisions. We in the US refuse to drill in much in fact most of the available areas because of supposed environmental concerns. This doesn't stop the rest of the world from doing so with much looser contrals than we have. A classic case in point is the current plans of China to drill in the golf of Mexico. We feel it's "too ecologically sensitive" so instead the Chinese will drill there with Cuban basing and look how much they care for the environment. The DDT ban was one of the motivating pieces in the rapid development and growth of the chemical industry in India. Did they build facilities that would have passed environmental muster in the US? The US has had improving air quality for more than a generation now, but still the first thing I would suggest is replace all coal burning electric power plants with nuclear. If any interest group that was pushing the AGW agenda would adopt that idea I would not only support it, I'd be a lot more ready to believe they believed in AGW. As it is I don't think they do. Instead we get bio fuels garbage that at best only rasies food prices and likely makes things worse.
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  5. Well then, you must have plenty to say about these links, especially the Ames 1966 and the Van Veltzen et al 1972 studies. I'm especially curious to hear about the Miller et al 2001 study, which I found quite interesting and has the advantage of underlying the enzymatic processes by which shell thinning occurs. Also, it would be nice to provide links or references to scientic work substantiating this assertion: "It just happens that issue really bugs me because the ban did so much more harm both to humans and to the environment than DDT ever could." It's vague and very wide, you need to give more (scientific) info on that. It's not because acid rain was not a catastrophy that it should not have been stopped. What exactly are the reasons to tolerate swaths of forest and land bleached by acid rain? That nobody got killed on the spot? The convenience for the industry causing it? I dont' think so. "The DDT ban was one of the motivating pieces in the rapid development and growth of the chemical industry in India. Did they build facilities that would have passed environmental muster in the US?" No, but why exactly is that a good thing? I agree on the nuclear idea and the "biofuel Garbage" notion, except that not all biofuels are garbage. Some could be promising, depending on the source, but the corn lobby has hijacked the all thing and corn is just about the worst source for biofuel. Your reasoning about the Golf of Mexico makes no sense. You are saying that because we don't do something bad, others are doing it. They would do it anyway, the US not drilling it is not the cause of their drilling. And then you say that because they do it, we should do it too. And my Shanghai story does not bring that point up at all, I don't see how you make that jump. Plus, you keep attributing to me views that are not mine. In my opinion, the G of M is a place where drilling might not necessarily be that harmful, provided it is properly monitored and everyone is accountable for their actions. Then you go on to say that the US has improved air quality, which is entirely true (albeit unrelated) and that was actually the point of my Shanghai story. The US has improved air quality because of the Clean Air Act. If you don't want to live in a place like Shanghai, you need regulations like the CAA. In fact, equally strict or stricter regulations should be in effect worldwide. I'd add that it's not because the rest of the world has weak standards (which, by the way, is not the case everywhere, China and India are obviously problematic and as such, bad examples) that we should have weak ones too. Do you stop living a principled life if you notice that your neighbor is a rake?
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  6. The other stuff will take me some time. The US is not the only place with good environmental regulations, I am sure some places do a better job. Some clarifications: Stopping acid rain to a large extent did not require an end to internal combustion engine transportation, or the de-industrialization of the world; which were the proposed solutions of the panic spreaders at the time. On the Golf of Mexico. The US refuses to develope it therefore China does... The Chinese company will not have to meet the stringent environmental requirements of a US company and will not be forced to clean up any mess they make, which a US company would be. Therfore we get reduced benefit coupled with increased risk of harm to the environment. This is the general pattern in a lot of industries, if we force the industries into places where environmental concerns are ignored the net effect to the environmment is much worse. A factory in the US has strict emission requirements, a factory in Shaghai probably doesn't. So what happens is we give a competitive advantage to the country that does the worst job on the environment. Rather than regulation we have created a system that indirectly prohibits the building of cleaner facilities in the US in favor of dirtier ones abroad. Not fixing the pollution problem but only shifting it out of our control. The net effect is a dirtier planet for everyone. You will notice I did not say there is anything wrong with US standards being high. But if they cause the facilities to be built elsewhere it defeats much of the purpose. I don't se an easy or even a good answer to this problem. On the harm of the ban, the ban of DDT did not stop or even reduce pesticide use. In fact it greatly increased the size and profit margins throughout the market. Which replacement for DDT could anyone argue in favor of? Which replacement was not much worse? Paration? Malthion? tetra-arsino-lead? The ban did make effective control of insect spread disease much more difficult and expensive. I think we are talking past each other a little here, I am much more focused on relative harm, the idea of any perfect solution is unrealistic to me and I think panic mongering tends to enable really bad policy decisions. I don't understand your one comment It seems you are saying that India building more dangerous and polluting chemical plants is good? Did you misread my point there? It isn't a good thing it is an unintended consequence of a bad policy decision.
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  7. Philippe Chantreau I am sorry that you misunderstood my reference to Gerlich. I do not agree with his paper. I was trying to point out that in theory tou could prove almost anything with the right math. I was looking for a comment explaining WHY he was wrong, not THAT he was wrong. That is why I only mentioned it once. When I agree with a paper, such as Mackey's, I tend to mention it more often to see if anyone can rebuff it.
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  8. Quietman: "I do not agree with his paper. I was trying to point out that in theory tou could prove almost anything with the right math." That's exactly the point. Gerlich paper does not prove anything. His maths are dead wrong. Look it up at Rabett's. Just like Goodridge, and D'Aleo, and Copeland's maths are wrong, as analyzed in these posts: http://tamino.wordpress.com/2008/03/27/how-not-to-analyze-data-part-1/ http://tamino.wordpress.com/2008/02/03/exclamation-points/ http://tamino.wordpress.com/2008/03/30/how-not-to-analyze-data-part-deux/#more-663 However, for the non maths savvy, it could very well look credible if you don't dig deeper, especially because they're not intrinsically wrong, but wrong in their application. That's exactly what denialism is about. It does not foster debate, scientific integrity or diversity of opinion. It's just skillful BS. WA: You commented about India building less than par chemical plants, as if it was a good thing, and I asked why that would be a good thing. Your comment, not mine, suggested that it was a good thing. To make it clear: it's not. Large amounts of DDT tend to quickly yield very resistant organisms. See for example this paper, which is one of many: http://www.anobase.org/embo_meeting/2005/abstracts/Coetzee.pdf There is no such thing as a silver bullet. The wikipedia articles may not be at the level of environmental chemistry grad school but nonetheless seem more informative than what you've said so far, which was so black and white as to have no bearing to the historical reality of the product's use in the world. http://en.wikipedia.org/wiki/DDT#cite_note-Thurow-83. Plenty of references there. Throwing around molecules or brand names is impressive but does not replace scientific studies. References? "The ban did make effective control of insect spread disease much more difficult and expensive." Please substantiate. Links, studies, references? Your claim on the patent and timing of DDT use is wrong. It was first patented in 1943 and the peak use occured in 1959 (80 million tons, per EPA records), mostly on cotton crops, before the patent expiration. I'm a little surprised that, as someone who spent countless grad school hours working on that issue you don't seem to have a ready answer to, at least, the Ames 1966 paper. How about the DDT reliant WHO program that ended up with initial gains reversed when resistance kicked in? Could the switch to Malathion and Bendiocarb be due to the lost effectiveness of DDT rather than a ban that does not even exist in the countries where the problem is? I'll cite wikipedia for a change: "Today there is debate among professionals working on malaria control concerning the appropriate role of DDT. The range of disagreement is relatively narrow: Few believe either that large scale spraying should be resumed or that the use of DDT should be abandoned altogether." That's almost always where reality lies. Remember that I told you I did not think banning it was a good decision? However, I don't think that using millions of tons of it, on cotton crops or elsewhere, was good either. As for drilling in the G of M, your logic still does not hold. The vast majority of it is international waters, in which the US has no jurisdiction. China would drill there as it would anywhere else, regardless of what the US is doing. If CNOOC goes on drilling off the Nigerian coast, is that the because the US is not there (which it is)? Obviously not. You keep on suggesting causality that does not exist on this. And we don't force industries in places where they can do anything they want. Industries do their part, which is completely removed from certain considerations, but is nevertheless a matter of CHOICES made by human beings. They try to make as much money as they can, by all means they can come up with, so long as the cost-benefit balance is favorable. In that sense, one can say that capitalism is a profoundly amoral ideology. It does not even matter whether or not something is legal. If it's not, but doing it is overall financially advantageous now, corporations will do it anyway, regardless of the location (it happens in the US and developped countries too). That's how laws are broken and fines are paid because paying the fine is compensated by the profits generated from ignoring the law. There are things that money can't buy. Some crucial aspects of your quality of life are among them. Corporations do not worry about the big picture, or even the long term (see the housing bubble fiasco). Minding about the long term or the big picture belongs to us, the people, and our representatives. It is perfectly possible for an oil refinery (or a pipe factory, ot any other business) in the US to make profits and respect all environmental laws. It will make more profit, however, by operating somewhere without environmental laws. Or somewhere without labor laws. Or somewhere child labor is not frowned upon. Or whatever. By doing so, it will transfer costs to the local populations, with degraded living conditions and a variety of health problems. That is not a way to foster human progress. Capitalism is overall benefical only when properly guided by regulations. Since it does not contain any moral bounds, they must be imposed upon it. Those who deny that ALWAYS have self serving motives, or they're just parrots regurgitating well drilled conditioning. The competitive advantage you mention is not given, it is crafted by corporations influencing international trade laws. The only reason why there are places where environmental and other concerns are ignored is that there are places where people are desperate. Exploiting their desperation to scrap additional pennies when other options exist is despicable, even if made legal by GATT/WTO. It is also a very short term and eventually losing proposition. It can be done only because these people are desperate. The moment they're no longer desperate, they'll start speaking up and fighting for the decent living conditions they deserve. It's already starting in China. And then, there goes your additional margin. If we are talking past each other, it's because you keep on bringing up strawmen built from the most outrageous claims of environmental advocacy groups. I do not defend outrageous claims, whatever the side. I am favorable to widespread use of nuclear energy, at least for the medium term, especially in China and India. I am not opposed to drilling in the G of M. I am unfazed by alarmist claims, regardless of where they come from (remember Baliunas and the CFCs?). Focusing on environmental alarmism is as stupid as focusing on economic alarmism put forth to resist change or regulation.
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  9. "Stopping acid rain to a large extent did not require an end to internal combustion engine transportation, or the de-industrialization of the world; which were the proposed solutions of the panic spreaders at the time." OK. So, I take it we agree that panic spreaders are to be disregarded and that acid rain has to be stopped. Which was really my point. I don't know about panic spreaders, I don't listen to that kind of stuff. I know about the effects of acid rain and I know that, as you said, there is no reason to tolerate it, since not doing so does not involve de-industrialization and so forth.
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  10. Philippe Thanks for the explanation and the links.
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  11. Except, environmental alarmism becomes public policy and law. Which makes your entire point that we can afford to ignore it and only pay attention to the science sadly wrong and deadly dangerous. If the "Ames " study was in the literature prior to 1980 that means I read it and everything associated with it at the time. Apparently neither I nor anyone at the University or EPA was convinced. Since I don't keep files of research from things I did 30 years ago I can't pull out every article I read. I think one thing you do well is find reference materials. That is helpful but you must have a lot more time than I have. USDA and EPA reports place the peak usage year for DDT as 1971 and as the ban was in 1972... My point that it was out of patent and therefore not very profitable is certainly still correct. If its use was declining that would further support my point that the chemical companies would not fight to keep it, so that would have been a piece of evidence that would tend to refute rather than support your comment on corporate culpability. Naming a few of the chemicals that replaced DDT in use is not a straw man. The simple question is were they less environmentally harmful? I didn't answer the question. More importantly neither did the environmental movement or the regulating agencies. I suspect that if you do dig into it you will find the answer is a resounding no. Actually much as I complain Phillippe, I suspect I actually would agree with you most of the time, as I do in this case. I just am more cynical about the danger of panic and the way politics is clouding the issues.
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  12. Actually, I really don't have that much time. It took me less than 10 minutes on Google to find the studies I linked, including the blurb pointing to the Miller study (the best one, it's got the pathophysiology). EPA places DDT peak use in the US in 1959 with 80 million pounds. 1971 saw the application of 13 million pounds. See this press release: http://www.epa.gov/history/topics/ddt/01.htm Took me less than minute to find this one by googling "DDT peak use." "I suspect that if you do dig into it you will find the answer is a resounding no." But you don't know, really. Until you do, you should abstain from claiming it as if it was a fact. And look up that Wikipedia article, it is quite informative and does not point to anything resounding, yes or no. Good ol' reality is never as spectacular as we'd like and keeps on not declaring any camp a true winner.
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  13. Well googling your suggestion which is not the way I would normally look things up... I find your number right away. I have an old Oklahoma Farm Bureau article here that has 1971 for peak. The OFB is supposedly world wide use. I wonder why they did that. I wonder if it's right? A number of other things in the article checked out. 1959 Still doesn't fit very well with eagle populations reaching their bottom in 1949 though? On the first page of the links that came up in the search is an Jounal of American Physicians and Surgeons article that is less complimentary of the ban than I am. This is classic internet, I get easier access to information and less certainty of it's accuracy. Journal of American Physicians and Surgeons Volume 9 Number 3 Fall 2004
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  14. A missing point in these thread is the snowalbedo. In januari 2008 northern hemisphere snowcover was on the highest since 1966, according to data from Rutgers university snow lab. There was extremely snowcover reported over large parts of Asia where it efficiently reflects solar heat. This caused the cooling as well. On the contrary, during march northern hemisphere snowcover was second lowest on record. Premature GISS-data shows that global temperature anomalie rises to 0.67°C. This means we're back on the stage and the drop in the winter was just an incident. @ Wondering Aloud, It seems to me that your particular argument in these discussion doesn't hold anymore. Which I don't mean that solar activity could be an important feature in climate change. You'd better find new arguments to criticize AGW. Regards, Victor
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  15. I don't know what particular argument you are talking about, I suppose up top? Where I didn't like his graph or see where he got it from? I think that is mostly resolved. I am not sure how big the solar affect is but it looks to me like it might well be half of the total signal fairly easily. I don't think the current solar minimum should show up as a temperature drop for quite some time yet, and only a sustained minimum should have any effect. We had a couple of centuries of generally increased solar activity. I have severe doubts that this last March was second lowest snowcover on record. I think I'd question how that data was gathered if they actually publish that conclusion. GISS? no problem with that data set... except the warming signal is primarily coming from an "adjusted" version of the land record. Remove the obviously flawed stations with large warming bias and the arbitrary cooling of the past introduced as "adjustments" from that record; than we can talk about it seriously. But if you do that half of the total signal vanishes... That is why we have a problem here. Fortunately there are at least 3 better data sets. Using the GISS one is not needed. No one wants to admit that we should do that though because it isn't so dramatic.
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  16. Wondering Aloud, That particular argument was about whether or not a decline in solar irridiance since 1985. It shows no correlation with temperature anyway. But I do believe there's a longer time lag between solar activity and temperature since solar irradiance penetrates deeper in oceans (as I suggest elsewhere on this site). So if solar activity slightly increased past decades it's warming effect could hold on longer but a lag of 35 years seem too long. Another problem is that solar effects mis the temperature peak around 1940 when you lag it. What I wrote about snowcover was my own conclusion simply based on data from the site below. Here you can find information about total northern hemisphere snowcover back to 1966. If you check the list I think you will assume the same. Clearly March had the second lowest snowcover for that month not for every month. About accuracy and calibrations of that data I have still to learn a lot. The same for the GISS-dataset (I wrote 'premature'). GISS didn't took Southern Africa in account which region was colder as average. http://climate.rutgers.edu/snowcover/index.php
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  17. Hi John I agree the La Nina has probably been dominant in this past year's cooling, we've had a steady succession of pos & neg PDOs since 1998 while the temperature trend line hasn't really risen much. Although it's oscillated quite a bit, but even the Keenlyside paper says (paraphrased) "don't get complacent, just you wait and see." There's a problem, however. The sun has already dimmed by -0.1 degrC since the early 1990's (that'd be -0.33 w/m-2). And then the '98 el Nino belched out a fair amount of heat & something changed. And we have various astrophysicists saying we're due for another -0.33 to -0.66 watts/m-2 reduction in TSI by 2025 with both plasma and magnetic dynamo models indicating an incipient slowdown .. equiv. to another -0.1 to -0.2 degrC decrease. The amt of variability in TSI is controversial but in 2001 D. Shindell modeled the Maunder Minimum's role in the Little Ice Age. He modeled a UV decrease due to the absence of sunspot faculae - the cooler stratosphere in turn cooling the upper troposphere. The cooling effect of the post-Pinatubo ozone depletion had similar effects on the upper troposphere (the Pinatubo masking effect...). But what Shindell modeled was a -0.3 to -0.4 degr. C. overall decrease in global temperatures. What we're looking at in the current solar situation is in the lower bound of Shindell's model for the LIA. OK, now with natural ozone recovery that variable could be offset as well, even zero-sum, or the reduced facular UV could lead to a net cooling -- does anybody know? Understand I'm not claiming we're due for another LIA, that's too facile for me. But a cooler stratosphere & upper troposphere would ultimately serve as an offset to already extant warming as would soot mitigation (Ramanathan, Zender), ground-level ozone reduction and so on. Recently Kevin Ternberth of NCAR went on record speculating that the Argo floats (data now recalibrated and all...) aren't finding the extra heat b/c it looks like it radiated back out into space (via ENSO?). I understand the seas have a roughly 10-year lag after solar cycles, so I'm wondering if Argo data are reflecting the gradual decrease in TSI. I have to wonder then if Hansen's "heat bucket" heat pipeline is such a sure thing. Also other studies are showing that humidity in the mid troposphere & over Antarctica aren't as high as had been modeled, with interesting implications for interglacial evidence. What say you? Thanks!
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  18. John, I liked your comment, "The flaw in this interpretation is in drawing conclusions about long term climate change over a relatively short period". In the history of the Earth, 100 years is a "relatively short period", so the same could be said about drawing conclusions about observations over that time frame. There's only one absolutely certainty about climate... and that is that it WILL change.
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  19. This site needs updating in light of the greatly reduced sunspots of Solar Cycle 24. It appears now to be a repeat Dalton minimum with overtones of morphing into a new Maunder minimum if the sunspots flat lines out after 2015. Some believe we are in for several decades of global cooling. Will global cooling or anthropogenic global warming become more pronounced as the years roll forward?
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    Moderator Response: Henry, you've already posted a very similar comment in the thread What would happen if the sun fell to Maunder Minimum levels?. Quite a few people have replied to your comment over there. Please keep discussions of a hypothetical future Dalton/Maunder Minimum confined to that thread.
  20. Henry, before continuing with idea that reduced sun is going to cause global cooling, please state why you disagree with the conclusion of Feulner and Rahmstorf (2010)
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