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Philippe Chantreau at 18:16 PM on 17 July 2009Climate time lag
Furthermore, we're looking at a pressure near or below 1 atmosphere. Carbonic snow on Earth? Only the so-called "skeptics" come up with that kind of stuff. -
Philippe Chantreau at 18:06 PM on 17 July 2009Climate time lag
Robbo, it's very simple. CO2 exists in the atmosphere at 387 ppm. We're not talking about freezing 100% CO2 in gas form. -
thingadonta at 13:43 PM on 17 July 2009Climate time lag
Can some 'global warmists by humans' care to explain this revealing sentence from Hansen 2005, claiming we have an energy imbalance in the atmosphere, and still have 0.6 degrees in the pipeline?? "First, the predicted energy imbalance due to increasing greenhouse gases has grown to 0.85 ± 0.15 W/m2". I'll clarify: How many circular assumptions kiddies are in this statment?? I count 3. 1. "predicted energy imbalance"..ie based on their being an energy imbalnace due to c02 driving T. 2."due to increasing greenhouse gases"-which assumes that they are driving T. No mention of the sun in the article, or heat lag from such. 3.Has grown-ie if you assume the first 2 you get the last-"has grown". Hansens 2005 paper is NOT a refute to the heat-lag sun dominant-driver argument, it is just a re-iteration of the creed of c02 driving warming. IE 'We know that the heat lag from the sun isnt approaching ewquilibrium because c02 is driving warming, which means there must be a 'predicted' energy imbalance'. A perfectly circular argument. Sounds like 'bankspeak' to me, I wouldn't invest my money in it. Nor should any country.Response: You're misreading what Hansen is saying. If you read the whole paper so you have the full context, you'll see that Hansen 2005 is saying that:- We predict there will be an energy imbalance due to increasing CO2.
- Empirical observations of increasing ocean heat confirm there is an energy imbalance.
- The energy imbalance, calculated from ocean heat measurements, is steadily growing and is currently at 0.85 W/m2
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Robbo the Yobbo at 12:58 PM on 17 July 2009Climate time lag
Mr. Yobbo to you Chris - I don’t really think you have had time to read the Alaskan paper I referenced last. Nice link to the global SST. I am sure you recognise that the Nino 3.4 area is in the central Pacific Ocean. The graph is comparing global anomalies to central Pacific sea surface anomalies. It shows the dominance of changes in Pacific Ocean processes in the global mean. Here’s a good link to a number of relevant indices. http://ioc3.unesco.org/oopc/state_of_the_ocean/all/ I have a web site with some information of the relevance of these indices and a description of the physical processes involved in the Pacific dominance. Something I occasionally update as my interests develop. www.earthandocean.robertellison.com.au I think your graph illustrates the Pacific dominance well - and I will certainly go back to it. But we know that atmospheric temperature and total ocean heat content has plateaued on perhaps a thousand year high. Yep – it’s warm alright (except in Vostok). All that I am saying is that there is a very obvious 50 year cycle superimposed on background warming. The Nino 3.4 data clearly shows the difference between the 1946 to 1975 state and the 1976 to 1998 state. This can be more clearly seen in the Multivariate ENSO index of Wolter Claus (http://www.cdc.noaa.gov/people/klaus.wolter/MEI/ ) – or the related PDO index (http://jisao.washington.edu/pdo/PDO.latest ). Here’s a great paper on the interactions of ENSO and the PDO. A cool mode PDO is associated with more frequent and intense La Niña and, conversely, a warm mode is associated with more frequent and intense El Niño. Verdon, D. and Franks, S. (2006), Long-term behaviour of ENSO: Interactions with the PDO over the past 400 years inferred from paleoclimate records, Geophysical Research Letters 33: 10.1029/2005GL025052. Statistically, a weak El Niño or neutral conditions is more likely than a return to strong El Niño. The current Nino 3.4 anomaly is at 0.63 °C for the week ending July 11. The definition of an El Niño is sustained sea surface anomaly of greater than 0. 5°C for five months. Look at your Nino 3.4 graph at the bottom. The recent La Niña was not exceptional at all and we have barely scratched the surface an El Niño yet people are jumping on the bandwagon – and hoping like hell things will turn around. The PDO and ENSO states have been mixed since 1998. Swanson et al – uses a global sea surface temperature synchronisation technique to posit shifts in climate state. They were very pleased with themselves for using an objective technique rather than eyeballing it in. I think the terminology is useful and the methodology promising. http://www.uwm.edu/~kswanson/publications/2008GL037022_all.pdf http://www.realclimate.org/index.php/archives/2009/07/warminginterrupted-much-ado-about-natural-variability/and Dodgy sources I know – but what can you do? NASA nominated a switch to a cool PDO since 2008. The anchovy index indicates a shift in post 1998 - http://news.bio-medicine.org/biology-news-2/From-sardines-to-anchovies-and-back-in-50-years-5939-2/ Now I’m just being provocative – I’ll get the missus to spank me. Try instead: http://alexeylyubushin.narod.ru/Climate_Changes_and_Fish_Productivity.pdf You are very out of your depth here Chris Cheers Robbo -
shawnhet at 10:56 AM on 17 July 2009Climate time lag
Chris, the 0.5C number is an equilibrium number(after albedo etc...). Your "simple" calculation doesn't take that into account. Yes, the CO2 effect might *in equilibrium* cause a temperature increase of about 0.5C. Since most of that Also, in re:land use changes, while they may release more CO2, they have cumulativelty also changed albedo resulting in a cooling of around 1/2 the warming due to CO2 you are talking about(if memory serves). see for instance Brovkin et al. (1999) IAC, the reasons for suspecting a CRF climate-link was explored in many, many papers on Kirby, I don't see the point of talking about each one in detail. Fact is, you asked for reasons to suspect that there is something about CRF specifically that influences climate, I provided it. I don't have any desire to eliminate all doubt in your mind. Cheers, :) -
chris at 09:50 AM on 17 July 2009Climate time lag
re #99 Robbo, your odd and unsupported assertions seem strangly divorced from reality. What are you think of? There isn't any non-arbitrary evidence that the climate has shifted post 1998. 1998 was just an anomalously warm year on a rising trend. If one considers the 10 record warm years (NASA Giss) all of the 2000's years are greater than all of the 1990's years except for 1998 and 1997: 2005 1998 2002 2003 2006 2007 2004 2001 2008 1997 2008, despite the large La Nina and the sun sitting stubbornly at the bottom of the solar cycle, is the 9th warmest year on record. 2009 will almost certainly be warmer than 2008 and so only the highly anomalous year of 1998 will be in the top ten. Despite your assertion of a climate shift and an extended cool period (none of which has any basis in non-arbitrary assesment), we seem to be entering the early stages of an El Nino. The El Nino/La Nina pattern doesn't seem to be different pre-1998 vs post-1998 [see *]. The sea surface temperature in June was the second warmest month on record [*]. [*]http://data.giss.nasa.gov/gistemp/graphs/SST.glob+Nino3.4.pdf Now of course one should be careful in drawing conclusions from short periods. But it's difficult to relate your assertions of cooling with the observation that despite the fact that we've just come through a strong La Nina, and the sun is right at the bottom of its solar cycle (I thought you guys were arguing for a very strong solar contribution to climate???) and seems to be sitting there in a rather protracted manner, that the global sea surface temperature is almost as high as in the very anomalous 1998. -
Robbo the Yobbo at 09:20 AM on 17 July 2009Climate time lag
Chris - Even the IPCC concentrates on the past 50 years. I think your being to precise with paleo graphicic data. I eyeballed in the Vostok data. Multi- decadal climate shift seem especially significant in the Arctic and North America as a whole. The graph of Arctic temperature is a goo d place to start. The following contains a more detailed discussion. The Significance of the 1976 Pacific Climate Shift in the Climatology of Alaska Brian Hartmann and Gerd Wendler http://ams.allenpress.com/perlserv/?request=get-abstract&doi=10.1175%2FJCLI3532.1 -
chris at 08:56 AM on 17 July 2009Climate time lag
whoops that table didn't format terribly well!1006.0000 279.4000
means that the year is 1006 AD and the [CO2] atmospheric is 279.4 ppm2001.0000 373.0000 1.6000
means that the year is 2001 AD, the [CO2] atmospheric is 373 ppm, and the increment for that year (2001) is 1.6 ppm. -
chris at 08:52 AM on 17 July 2009Climate time lag
Robbo, this is an oddly false assertions...what were you thinking of?: "Temperature rise to 1945 was largely natural – in that CO2 concentrations of 300 ppmv is par for the course for an interglacial. Please note that the IPCC talks about the last 50 years. CO2 levels started rising after the mid 1940’s – and temperatures declined for 30 years." No. The natural interglacial concentration is 270-280 ppm. We can assess this in great detail for the present interglacial [*]. The preindustrial concentrations were very close to around 277 +/- ~ 5 ppm since around 1000 AD to the preindustrial period. Significant anthropogenic contributions to atmospheric CO2 started around the start of the 19th century (land use changes largely at that point) and CO2 concentrations had reached around 310 ppm by around 1940. That CO2 rise is expected to give a contribution to the earth's global temperature of around 0.5 oC at equilibrium (using the median value of the climate sensitivity of 3 oC). So the pre-1945 temperature rise was very unlikely to be natural. Quite a large chunk is almost certainly anthropogenic. Note that the rather rapid increases in anthropogenic CO2 only started after post-war industrialisation especially from the early 1960's ([CO2] levels were still only 320 ppm in 1962). They really started to race upwards from around that time (see data below). Of course the IPCC doesn't just "talk(s) about" the last 50 years. Why not try reading some of the IPCC reports rather than just making up stuff? 1006.0000 279.4000 1046.0000 280.3000 1096.0000 282.4000 1146.0000 283.8000 1196.0000 283.9000 1246.0000 281.7000 1327.0000 283.4000 1446.0000 281.7000 1499.0000 282.4000 1547.0000 282.8000 1589.0000 278.7000 1604.0000 274.3000 1647.0000 277.2000 1679.0000 275.9000 1720.0000 277.5000 1760.0000 276.7000 1796.0000 283.7000 1825.0000 285.1000 1845.0000 286.1000 1861.0000 286.6000 1877.0000 288.8000 1882.0000 291.7000 1891.0000 294.7000 1899.0000 296.5000 1905.0000 299.0000 1912.0000 300.7000 1926.0000 305.0000 1936.0000 307.9000 1948.0000 311.4000 1954.0000 314.7000 1959.0000 315.7000 1959.0000 318.2000 0.9400 1960.0000 319.2000 0.5000 1961.0000 319.7000 0.9600 1962.0000 320.7000 0.6500 1963.0000 321.3000 0.7400 1964.0000 322.0000 0.3000 1965.0000 322.4000 1.0700 1966.0000 323.4000 1.2600 1967.0000 324.7000 0.6800 1968.0000 325.4000 1.0400 1969.0000 326.4000 1.3700 1970.0000 327.8000 1.0000 1971.0000 328.8000 0.7800 1972.0000 329.6000 1.7900 1973.0000 331.4000 1.1800 1974.0000 332.5000 0.7600 1975.0000 333.0000 1.0900 1976.0000 334.0000 0.9000 1977.0000 335.3000 2.0700 1978.0000 337.4000 1.3400 1979.0000 338.7000 1.6400 1980.0000 340.0000 1.8400 1981.0000 342.0000 1.4400 1982.0000 343.6000 0.7100 1983.0000 344.0000 2.1600 1984.0000 346.4000 1.3500 1985.0000 347.8000 1.2200 1986.0000 349.0000 1.5100 1987.0000 350.0000 2.3500 1988.0000 352.8000 2.1100 1989.0000 355.0000 1.2800 1990.0000 356.2000 1.3100 1991.0000 357.6000 0.9900 1992.0000 358.5000 0.4500 1993.0000 359.0000 1.3100 1994.0000 360.3000 1.8900 1995.0000 362.2000 2.0100 1996.0000 364.2000 1.1900 1997.0000 365.4000 1.9800 1998.0000 367.4000 2.9500 1999.0000 370.0000 0.9100 2000.0000 371.2000 1.7800 2001.0000 373.0000 1.6000 2002.0000 374.6000 2.5500 2003.0000 377.1600 2.3100 2004.0000 379.5000 1.5400 2005.0000 382.0000 2.53 2006.0000 384.0000 2.00 D ata are from: D. M. Etheridge et al (1996) "Natural and anthropogenic changes in atmospheric CO2 over the last 1000 years from air in Antarctic ice and firn J. Geophys Res. 101, 4115 -4128, and direct measurement from the Mauna Loa station from 1959 Column 1 is the year, column 2 is the [CO2] in parts per million, and column 3 is the yearly increment in the period from 1959. Ice core data from Etheridge (up to 1959) from a series of Antarctic (Law Dome) cores. -
chris at 08:23 AM on 17 July 2009Climate time lag
I did read that in Kirkby's review, shawnet. This specific point that you cut and pasted doesn't accord with the evidence for two reasons. (i) Kirkby has very oddly attempted to treat every last bit of paleoclimatology in terms of the CRF. It leads to some ludicrous interpretations which we could discuss. He completely discounts any possible contribution from greenhouse gas variations stating in a footnote at the outset, this rather audacious illogic falsehood: "Greenhouse gases are not included since, prior to the twentieth century, short-term changes of greenhouse gases, such as occurred during glacial-interglacial transitions, are found to be a feedback of the climate system and not a primary forcing agent [11]." Perhaps you didn't read my post above (#88), but it's very straightforward to assess the CO2 concentrations through the last 1000 years from a number of Antarctic cores drilled at Law Dome. The pre-industrial CO2 concentration was near 280 ppm (reduced to around 276 at the Maunder minimum) and was around 310 ppm by 1940. Within a climate sensitivity of 3 oC, it's also straightforward to calculate the temperature rise at equilbrium resulting from a 276-310 increase in atmospheric CO2. It's near 0.5 oC. So Kirkby's assertion that you cut and pasted is bogus as is his astonishing footnote. We expect that the temperature rise from the CO2 change (virtually all of which is anthropogenic), to be very significant indeed (something approaching 0.5 oC) between the Maunder minimum and the mid-20th century. (ii) Kirkby comes up with a tiny value for the solar irradiance contribution to warming from the Maunder minimum to the mid 20th century. He's right that the value is not very large. However, the solar scientists that actually determine the solar irradiance reconstructions consider that the irradiance contribution is somewhat larger than that. Lean calculates a solar irradiance contribution near 0.9 oC between 1890 and the present with almost all of this before the mid 20th century. The Maunder minimum to mid 20th century contribution is likely near 0.2 oC (see reference in my post #88 – her 2008 paper). So Kirkby's argument just doesn't accord with the evidence. There is a well-characterised source for a large contribution to to the temperature rise between the Maunder minimum and the mid-20th century. Kirkby also ignores the volcanic contribution to the Little Ice Age cold [*; see Figure 7]. But then his review rather astonishingly ignores anything that can't be interpreted in terms of the CRF…. [*] P.D. Jones and M.E. Mann (2004) Climate over Past Millenia (2004) Reviews of Geophysics, 42, RG2002. -
Robbo the Yobbo at 07:17 AM on 17 July 2009Climate time lag
idiocy, stupidity, abnormal psychology, aggressive – is there a pattern emerging here? But the mildest reply and my feelings are hurt? Phillipe –what part of Vostok minus 89 degrees – freezing point of CO2 minus 57 – don’t you understand? To continue with irrelevancies is silly. If I got the numbers wrong from my quick internet search – please tell me. Otherwise it is simply another straw man. I have no problem with technology, efficiency and innovation. Efficient and cost effective technology needs no assistance from government – except perhaps i in providing R&D funding of which not nearly enough is happening. People like Bjorn Lomberg consistently argue for more R&D and an economically rational transition. Nothing to do with giving any game away – increasing costs for energy in the third world is guaranteed to have a price in human lives. Temperature rise to 1945 was largely natural – in that CO2 concentrations of 300 ppmv is par for the course for an interglacial. Please note that the IPCC talks about the last 50 years. CO2 levels started rising after the mid 1940’s – and temperatures declined for 30 years. The usual explanation was that sulphur dioxide caused the dip. But the IPCC net forcing was always positive in the period. Climate shifted suddenly in the mid 1970’s to a period of more frequent and intense El Niño and rising temperature and has shifted again post 1998 – as in the Swanson et al paper and Real Climate blog I have already referenced. But the literature on PDO, AMO, ENSO multidecadal variation and decadal fisheries and ecological productivity is extensive. This is a 50 year climate cycle. Global temperature has declined and ocean heat content is at most steady since 1998. As in the Swanson paper shows – the underling trend of post war warming (across a full cycle of multi-decadal variation) that might be attributed to CO2 is 0.08 degrees centigrade per decade and the planet is cooling for another decade or two. -
shawnhet at 06:51 AM on 17 July 2009Climate time lag
Chris, I think you would be well served by reading the Kirkby review here/ From p.5-6 2.1.3 Solar and cosmic ray changes since the Little Ice Age The cold climate of the Little Ice Age appears to have been caused by an extended period of low solar activity. Few sunspots implies low magnetic activity and a corresponding elevated GCR flux. But could the observed warming since the Little Ice Age be explained by changes of solar irradiance rather than introducing the possibility of GCR-climate forcing? Recent results on Sun-like stars, combined with advances in the understanding of solar magnetohydrodynamics [8] have revised earlier estimates of the long-term variation of solar irradiance [5] downwards by as much as a factor of five (Fig. 5) [6, 7]. Apart from the irradiance changes due to sunspot darkening and facula brightening, no mechanism has been identified for solar luminosity variations on centennial or millennial time scales [8]. Current estimates of the secular increase of irradiance since 1700 are therefore based only on the variation in mean sunspot number. The increase in irradiance amounts to less than 0.5 Wm2, which corresponds to about 0.08 Wm2 at the top of the atmosphere, globally averaged (Fig. 5). Assuming a climate sensitivity of 0.7 K/Wm2, ***this would contribute less than 0.06C of the estimated 0.6C*** mean global warming between the Maunder Minimum and the middle of last century, before significant anthropogenic contributions could be involved. On the other hand, there is clear evidence of a substantial increase in solar magnetic activity since the Little Ice Age (Fig. 6) [55, 3]. http://arxiv.org/PS_cache/arxiv/pdf/0804/0804.1938v1.pdf "4. The fact that the CRF might vary more than solar irradiance (I assume you mean in terms of % variation around some mean), doesn't necessarily say anything about the relative contributions of the CRF changes and irradiance changes. After all, if CRF changes don't have a significant climate effect it doesn't matter how much these change." It does when the solar irradiance only has a slight ability to affect the climate(as per above for one of many examples), when the actual changes to the climate are much more extensive. If the magnitude of changes to climate and CRF are both large, then it follows that CRF is a better candidate than irradiance for the climate driver. If the magnitude of changes solar irradiance were of the same size as the changes in climate(or CRF), it would be simpler to assume irradiance was the culprit, but the magnitude is much too small. Cheers, :) -
chris at 05:30 AM on 17 July 2009Climate time lag
The problem with this line of argument is that total irradiance doesn't vary nearly as much as the climate has. Kirkby's 2007 review states that "...more recent estimates suggest that long-term irradiance changes are probably negligible". As such, since the total irradiance doesn't change much and the CRF does, the fact that CRF varies in tandem with climate changes, is good evidence that the CRF itself influences climate somehow.
That doesn't seem logical to me Shawnet. It begs rather a lot of questions. 1. The climate transitions since the Maunder minimum are understandable in terms of known contributions from solar, volcanic and greenhouse contributions (points 4,5 and 6 of my post #88). That doesn't mean that my breakdown of contributions is exactly correct! However one doesn't need to postulate any as yet uncharacterised forcings (solar or otherwise) to understand this variation. 2. That may or may not apply to the previous few centuries, e.g. involving the MWP. The climate variation during this period isn't so well characterised, and some of the climate variation may be regional and due to changes in ocean/atmospheric heat transport (my point 3 in post #88). Of course that begs the question of whether these heat transport variations are internal modulations of the climate system or are externally forced. 3. Previous to that there isn't a very good understanding of global Holocene climate variability I believe (I haven't seen serious Holocene global paleoproxy reconstructions other than these: Holocene_Temperature_Variations.png There are various bits of highly localized proxies (stalagmites; glacial ice etc.) which correlate solar proxies with climate proxies, but whether these are representative of global scale changes isn't very clear I think. So I'm not sure we can say that the total irradiance hasn't varied as much as the climate has, since we haven't got much evidence for the climate variability and solar irradiance variability during periods of the Holocene before a couple of millenia ago. Note that some of the early Holocene climate variability (around 8000-6000 years ago, I think) is a Milankovitch effect). 4. The fact that the CRF might vary more than solar irradiance (I assume you mean in terms of % variation around some mean), doesn't necessarily say anything about the relative contributions of the CRF changes and irradiance changes. After all, if CRF changes don't have a significant climate effect it doesn't matter how much these change. 5. Obviously climate has changed considerably in the past. But this is largely understandable in terms of earth orbital variations (Milankovitch cycles) with greenhouse gas and albedo feedbacks (last couple of million years), and further into the deep past through changes in greenhouse gas concentrations (rising CO2 concentrations from tectonic processes; reducing greenhouse gas concentrations from weathering processes), the progressively decreasing solar constant as we go back in time (Kirkby must surely know this, 'though perhaps by "long-term" he doesn't mean millions of years time scale), and tectonic activity. 6. So I'm not sure that we need to postulate any solar contributions outside irradiance changes. That's not to say that these don't exist (the evidence for the direct CRF-climate contribution is weak in my understanding of the science - e.g. see my post #71); it's just that they haven't been identified (to my knowledge), and aren't necessarily required to explain anything.... ...what do you think? Is there some serious evidence that some non-irradiance solar contributions are rwquired to explain particular climate transitions/variations? -
PeterPan at 05:15 AM on 17 July 2009Climate time lag
I've been trying to understand RC's post on a simple model in the light of this article and, if possible, I would like to understand the reason for a difference. According to RC's post: σTs4 = S /(1 - 0,5λ) Where S = (1-a)TSI/4 λ = emissivity (0,769) However, as I understand it, according to this article, that would rather be: σT4 = S/λ Using RC's notation: λ = ε (emissivity) S = what in this article is S(1-A)/4 Are my numbers wrong? Are the two approaches based on different simplifications? Thanks! RC's post Formulas better displayed here -
shawnhet at 04:22 AM on 17 July 2009Climate time lag
"Similar arguments apply even more strongly in the past. Changes in 10Be in ice cores and 14C in tree rings is a measure of varying solar outputs represented by the CRF. But just as with the very detailed contemporary analyses (see my post #71), there is no good a priori reason for assuming that any climate-related consequences of solar variation are causally related to the putative CRF component of the solar variation. In fact recent evidence suggests that this a priori assumption is a very weakly supported one." The problem with this line of argument is that total irradiance doesn't vary nearly as much as the climate has. Kirkby's 2007 review states that "...more recent estimates suggest that long-term irradiance changes are probably negligible". As such, since the total irradiance doesn't change much and the CRF does, the fact that CRF varies in tandem with climate changes, is good evidence that the CRF itself influences climate somehow. It is possible that some other solar-related property varies much more closely than CRF to the observed climate changes, but clearly irradiance changes themselves don't explain what we see happening. Cheers, :) -
Thumb at 02:25 AM on 17 July 2009Climate time lag
"Honestly - I link and quote a Stanford University website on what is a widely accepted understanding of space-time and a foolish little person insists on compounding their idiocy. Time would be better spent in expanding both their education and their imagination." Methinks someone's feelings were hurt. "'To make groupthink testable, Irving Janis devised eight symptoms indicative of groupthink (1977)." Now you're projecting. You gave your game away with this line: "...is not sufficient to warrant restricting the economic aspirations of billions of people." Your entire ongoing argument is based on finding anything, however small, that supports what I would argue is a false premise; that addressing our continued contribution to greenhouse gases would somehow have an adverse economic affect on "billions of people." In the real world in which I work converting to high efficiency and alternative energy sources creates jobs and holds an easily calculable payback when measured against current systems and fossil fuels, which, BTW, simply can't go on forever. Reducing greenhouse gases might be a driving force for some, but the real selling point for moving the global economy into green energy technologies is their potential to expand and enhance the economic aspirations of billions of people. -
Philippe Chantreau at 02:05 AM on 17 July 2009Climate time lag
Context is irrelevant in the case of the CO2 snow idiocy. No other context is necessary than the atmosphere of this planet. In this context, "broadly feasible" is so far off the mark that it's downright comical. No implication about climate needs to be considered at all. The idea is not fun, it's stupid, and anyone entertaining it as even remotely possible should be met with profound distrust on science considerations. -
Robbo the Yobbo at 23:16 PM on 16 July 2009Climate time lag
I have been edited - LOL 'The 2008 defensive reaction to the recent lack of global warming can be considered as another fine example of groupthink. A premature sense of apparent unanimity prevails (most scientists agree that global warming is real and manmade), and any doubts and contrary views are suppressed (by ... institutions launching lists of ‘correct’ answers to a number of critical questions (so-called myths), including the lack of warming since 1998).' 'To make groupthink testable, Irving Janis devised eight symptoms indicative of groupthink (1977). 1. Illusions of invulnerability creating excessive optimism and encouraging risk taking. 2. Rationalising warnings that might challenge the group's assumptions. 3. Unquestioned belief in the morality of the group, causing members to ignore the consequences of their actions. 4. Stereotyping those who are opposed to the group as weak, evil, biased, spiteful, disfigured, impotent, or stupid. 5. Direct pressure to conform placed on any member who questions the group, couched in terms of "disloyalty". 6. Self censorship of ideas that deviate from the apparent group consensus. 7. Illusions of unanimity among group members, silence is viewed as agreement. 8. Mindguards — self-appointed members who shield the group from dissenting information. Groupthink, resulting from the symptoms listed above, results in defective decision making. That is, consensus-driven decisions are the result of the following practices of groupthinking: 1. Incomplete survey of alternatives 2. Incomplete survey of objectives 3. Failure to examine risks of preferred choice 4. Failure to reevaluate previously rejected alternatives 5. Poor information search 6. Selection bias in collecting information 7. Failure to work out contingency plans. -
Robbo the Yobbo at 21:50 PM on 16 July 2009Climate time lag
Honestly - I link and quote a Stanford University website on what is a widely accepted understanding of space-time and a foolish little person insists on compounding their idiocy. Time would be better spent in expanding both their education and their imagination. Chris at least raises scientific issues – if in his usual disingenuous way. The 1150 year is of course the Usoskin correlation as he knows full well. I get it – you don’t think there is a link between clouds and cosmic rays and that natural climate variation is caused primarily by changes in solar irradiance. The usual consensus is that changes in irradiance are insufficient to explain observed climate variation. See for instance: Shortwave forcing of the Earth's climate: modern and historical variations in the Sun's irradiance and the Earth's reflectance, P.R. Goode, E. Palle, J. Atm. and Sol.-Terr. Phys., 69,1556, 2007. PDF I advise that there is an error on Figure 4 in that the left hand axis was mislabelled – which was brought to my attention by Chris misinterpreting this as a 20 fold reinterpretation of the data. I am very bored with the endless repetition of this argument and your dogmatic assertions – particularly so as I am barely involved in this line of argument. I merely referred to the Stanford University high energy physics site which suggests that the idea should not be dismissed out of hand – very much more in the spirit of scientific openness and debate. Much as is the work coming out of CERN and elsewhere. But you know best. I am much more interested in the empirical science of clouds, ocean temperature, rainfall and biology and in the climate transitions of the mid 1940’s, the mid 1970’s and following 1998. My exact words were that while ‘the causes are not clear, it seems clear that 1998 marked a transition in biological, oceanographic and climate systems. Transitions occur in the instrumental and proxy records on a 50 year cycle – and it is interesting to consider a heliospheric /cloud connection. It may be (however) that the cycle is a mode of internal dynamic variability that result in cloud changes. If you have 1 reference that questions this – I would be happy to hear of it. -
Alliecat at 19:47 PM on 16 July 2009Climate time lag
re: #86 "Can evolution be said to occur if the future form exists in a future moment in the time-space continuum?" This is gibberish. Do you really expect to be taken seriously by anybody when you write such bizarre nonsense as this? At least now your complete inability to follow the science makes some sense. Chris, your herculean efforts to bring facts and reason to the discussion (nice summary above BTW) are clearly wasted on somebody who writes such nonsense. This is no longer a scientific discussion, it is an exploration into abnormal psychology. Interesting, but other than learning about the psychological barriers to understanding that deniers have, it has little connection to science. Perhaps Robbo should go "debate" the timecube guy? -
chris at 19:21 PM on 16 July 2009Climate time lag
Re #76 Robbo, your aggressive splattering of ill-considered assertions supported by dodgy sources doesn't make a good impression. It's essentially trolling. Why not relax and try to consider these points scientiically rather than politically. Which 1150 year "correlation" are you thinking of? What do you think this correlation actually means? Try to think scientifically. Let's have a look: 1. we've already seen (my post #71), that despite some prodigious research efforts, a causal link between variations in the cosmic ray flux (CRF) and clouds hasn't been established. Recent research rather significantly decreases the likelihood of a causal link. If there is a correlation between the solar cycle and low level clouds the evidence indicates that this is discorrelated with the CRF and is causally related to irradiance changes. 2. Similar arguments apply even more strongly in the past. Changes in 10Be in ice cores and 14C in tree rings is a measure of varying solar outputs represented by the CRF. But just as with the very detailed contemporary analyses (see my post #71), there is no good a priori reason for assuming that any climate-related consequences of solar variation are causally related to the putative CRF component of the solar variation. In fact recent evidence suggests that this a priori assumption is a very weakly supported one. 3. There are clearly solar contributions to earth temperature variation during the past 1150 years. Scientific analysis of the likely contributions to variations in climate forcings during this period include solar, volcanic and greenhouse gas. Local variations (e.g. enhanced high N. latitude warming in the so-called MWP and cooling in the LIA) likely have contributions from changes in atmospheric and ocean currents that result in changes in heat transport from the equatorial regions to the high Northern latitudes (e.g. [*]. 4. Very detailed analysis of the strength of solar forcing variation by various solar experts determined by empirical analysis during periods where detalied observational data can be obtained [e.g. **, ***, ****] indicates that the solar irradiance contribution to warming from the period of very low solar proxies around the period of the so-called Maunder minimum in the LIA to the mid 20th century may be of the order of 0.2 oC. 5. Probably the most extreme paleoproxy analysis gives a reduced temperature of around -0.6 oC in the N. hemisphere relative to the mid-20th century temperature [*****]. It's likely that this event was somewhat focussed in the N. hemisphere event with the global temperature reduction a bit less than that, but even if we consider that the full global temperature was 0.6 oC cooler then than now, one doesn't need to postulate uncharacterized CRF contributions for which there is no evidence. 6. It's easy to determine the expected contribution of enhanced greenhouse concentrations since we know the CO2 concentrations right through the last 1000 years [******]. These were around 276 ppm at the time of the Maunder minimum and around 310 ppm around 1940. Within the mid range of likely climate forcing (3 oC of warming per doubling of atmospheric CO2 [*******], it's easy to calculate that the equilibrium response resulting from a change of CO2 from 276-310 ppm is around 0.5 oC. There's also good evidence form volcanic ash in cores that there was likely a small contribution from the high volcanic activity in the period of the LIA. Say around 0.1 oC. 7. So why bring in an uncharacterized hypothesised contribution for which the evidence is increasingly poor? Yes there are some correlation between Be and carbon isotopes and climate but we can understand these in terms of solar contributions to both climate and to the CRF flux. These both correlate to the solar properties. It's illogical to assume that this constitutes an a priori causal relationship between the CRF and climate. Recent evidence (see my post #71) indicates that this is an assumption that has little support in evidence. 8. Not sure what your unpleasant insinuations about my understanding of energy and energy flux refers to. Try to be a bit more explicit with criticisms – dumping post after post containing poorly-attributed and vague assertions ain't science Robbo. We can see you have strong political views but why not get in the spirit of this website and stop trolling. [*]Lund DC et al. (2006) Gulf Stream density structure and transport during the past millennium, Nature 444, 601-604 [**] Foukal, P. (2002), A comparison of variable solar total and ultraviolet irradiance outputs in the 20th century, Geophys. Res. Lett., 29(23), 2089, doi:10.1029/2002GL015474. [***]Lean, J. (2000), Evolution of the Sun’s spectral irradiance since the Maunder Minimum, Geophys. Res. Lett., 27, 2425–2428. [****] Lean, J. L., and D. H. Rind (2008), How natural and anthropogenic influences alter global and regional surface temperatures: 1889 to 2006, Geophys. Res. Lett., 35, L18701 [*****] Moberg, A et al. (2005) Highly variable Northern Hemisphere temperatures reconstructed from low- and high-resolution proxy data Nature 433, 613–618 (2005) [******]D. M. Etheridge et al (1996) “Natural and anthropogenic changes in atmospheric CO2 over the last 1000 years from air in Antarctic ice and firn J. Geophys Res. 101, 4115 -4128 [*******]R. Knutti, G. C. Hegerl (2008) The equilibrium sensitivity of the Earth's temperature to radiation changes Nature Geoscience 1, 735-743 -
paolo75 at 19:07 PM on 16 July 2009Global warming stopped in
1998,1995,2002,2007,2010, ????
Hi, to evrybody. I'm new on this 'very-well-done' site. I'm italian and not a great english speaker/writer, but I'm sure you fine people will forgive me. I just want post a question on this arcticle. I read in it that to cause a chute of 0.6 degrees it need a 13 W/m2 fall of TSI. OK, so far so good. This other article say "The correlation between sun and climate ended in the 70's when the modern global warming trend began." So, if i understand, before 1970 the sun was the cause of climate variation. And in the graph i see that (before 1970) a variation of less than 1 W/m2 causes a temparature increasing of almost 0.4 degrees. It is not that a contradiction? I'm sure i'm missing something... ThanksResponse:The sun was not necessarily the primary cause of climate variation before 1970. In fact, the forcing from solar variation is not particularly large. The breakdown in correlation is just to show that the sun cannot be the cause of global warming in the last few decades.
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Robbo the Yobbo at 17:19 PM on 16 July 2009Climate time lag
Based on this sort of feedback reasoning, I predict that their T predictions, energy imbalances, and such, will just keep going up and up, because there is nothing stopping their "self-reinforcing reasoning feedback loops" from just getting larger and larger. Meanwhile - the duck rides the bicycle around and around at relativistic speeds until it disapears up it's own ring in a secular humanist universe Actually, the duck experiment seems to work well. Thanks Thingadonta. -
Robbo the Yobbo at 16:51 PM on 16 July 2009Climate time lag
re 82 Nothing to do with heat lag but the connection is with the arror of time. The past lost - the future unformed - all there is the evolving moment which moves forward in time like an arrow. Space-time does not evolve - it simply exists. ‘It is believed to be a 'continuum' because so far as we know, there are no missing points in space or instants in time, and both can be subdivided without any apparent limit in size or duration. So, physicists now routinely consider our world to be embedded in this 4-dimensional Space-Time continuum, and all events, places, moments in history and in the future, actions and so on are described in terms of their location in Space-Time.’ http://einstein.stanford.edu/content/relativity/q411.html Can evolution be said to occur if the future form exists in a future moment in the time-space continuum? Meanwhile - the duck rides the bicycle around and around at relativistic speeds until it disapears up it's own ring in a secular humanist universe. -
Robbo the Yobbo at 16:47 PM on 16 July 2009Climate time lag
re 82 Nothing to do with heat lag but the connection is with the arror of time. The past lost - the future unformed - all there is the evolving moment which moves forward in time like an arrow. Space-time does not evolve - it simply exists. ‘It is believed to be a 'continuum' because so far as we know, there are no missing points in space or instants in time, and both can be subdivided without any apparent limit in size or duration. So, physicists now routinely consider our world to be embedded in this 4-dimensional Space-Time continuum, and all events, places, moments in history and in the future, actions and so on are described in terms of their location in Space-Time.’ http://einstein.stanford.edu/content/relativity/q411.html Can evolution be said to occur if the future form exists in a future moment in the time-space continuum? Meanwhile - the duck rides the bicycle around and around at relativistic speeds until it disapears up it's own ring in a secular humanist universe. -
Adlai Gavins at 16:43 PM on 16 July 2009The CO2/Temperature correlation over the 20th Century
re #73 Thanks Alliecat. I'll check out the link. Cheers! -
thingadonta at 16:42 PM on 16 July 2009Climate time lag
I also strongly suspect, that Figures 1 and 2 above are based on model assumptions relating entirely to c02 driving T as well (see my previous post). They are therefore not evidence, jsut self-perpetuating data models, adjusted at whim as a modeller sees fit. Figure 1's 'runs' above are based on Hansens model assumptions of T being driven by c02 in his paper; figure 2 'erbs' and 'ceres' and also based on predicted fluxes-assuming an imbalance with respect to T being driven by c02. They are both therefore circular-reasoning graphs which dont show anything except the whims and assumptions of the modellers who compiled them. i have seen similar modelling assumptions in modelling work by financial instutions. -
thingadonta at 15:40 PM on 16 July 2009Climate time lag
Gewtting back to the topic of ocean-earth heat lag. Hansen 2005 states: "Levitus et al. (14) compiled ocean temperature data that yielded increased ocean heat content of about 10 W yr m-2, averaged over the Earth’s surface, during 1955-1998". Yes, as expected by heat lag from the sun to the 1990s. But then he states: "First, the predicted energy imbalance due to increasing greenhouse gases has grown to 0.85 ± 0.15 W/m2". In other words he ENTIRELY assumes that past century T rise is by greenhouse gases first, which has therefore created a "predicted energy imbalance", by "increasing greenhouse gases". If we assume an energy imbalanace, then we get an energy imbalance. Mindbloggingly circular and stupid. There is no evidence to conclude, as he does, that the there is an energy imbalance at present, unless one assumes that T is rising by C02 in the first place, as he states above, that he does. This is not proof, is is circular reasoning. If we assume an energy imbalanace, then we get an energy imbalance. He uses the same argument further down to get a figure of 0.6 degrees C still 'in the pipeline' ie from ocean heat content, ie imbalanced with c02 forcing. NOWHERE does he discuss or address or acknowldedge the fundamental assumptions of the models he bases this figure on, ie that he ASSUMES T rise is being driven by c02, and not the sun. Ill repeat it for the sake of clarity: "the predicted energy imbalance due to increasing greenhouse gases has grown" How many circular assumptions kiddies are in this statment?? I count 3. 1. "predicted energy imbalance"..ie based on their being an energy imbalnace due to c02 driving T. 2."due to increasing greenhouse gases"-which assumes that they are driving T. No mention of the sun, or heat lag from such. 3.Has grown-ie if you assume the first 2 you get the last-has grown. Based on this sort of feedback reasoning, I predict that their T predictions, energy imbalances, and such, will just keep going up and up, because there is nothing stopping their "self-reinforcing reasoning feedback loops" from just getting larger and larger. Meanwhile, T hasnt risen in the last 10 years, because it is not subject to the 'global warmists by humans' self-reinforcing reasoning-positive feedback loops. Heat lags have now stabilised, there is no energy imbalance, and T will not rise over the next 10-20 years, unless the sun becomes more active again. -
Alliecat at 14:31 PM on 16 July 2009Climate time lag
re #80: "I think that people who think that evolution doesn't need God don't understand Einsteins's space-time continuum." It's pretty clear that people who use the phrase "space-time continuum" in the same sentence as "evolution" don't understand either of those things. It's a bit like saying "i think that people who think that ducks don't need bicycles don't understand computers" - the sentence parses correctly, but really doesn't say anything useful... -
Robbo the Yobbo at 13:18 PM on 16 July 2009Climate time lag
Let’s have another quick look at clouds. There is a lot of useful data on Professor Ole Humlum’s homepage at: http://www.climate4you.com There are records of clouds from 1985. They show declining cloud cover to the turn of the century and increasing thereafter. Goode et al 2009 (can be found on the bibliography page of Project Earthshine – show this as albedo changes of a decrease in Earth albedo of 1% (additional shortwave of 3.5 W/m2) and an increase after 1999 of 0.75 % (less shortwave at the surface of 2 W/m2). High and low cloud in the climatically important equatorial zone declined to 1998 and increased thereafter. While the causes are not clear, it seems clear that 1998 marked a transition in biological, oceanographic and climate systems. Transitions occur in the instrumental and proxy records on a 50 year cycle – and it is interesting to consider a heliospheric /cloud connection. It may be that the cycle is a mode of internal dynamic variability that result in cloud changes. -
Robbo the Yobbo at 11:11 AM on 16 July 2009Climate time lag
David, I don't deny that I am both a theist and a capitalist. I think that people who think that evolution doesn't need God don't understand Einsteins's space-time continuum. In the context of that discussion - my comment was in relation to stable democracy, small government, minimally regulated capitalism and the reduction in global poverty. I can't help if you have a problem with that but this is not the place and I didn't raise the subject. -
Robbo the Yobbo at 10:57 AM on 16 July 2009Climate time lag
Philippe, 'The freezing point of carbon dioxide is -57 degrees centigrade. The lowest temperature ever recorded was -89.2 at Vostok in 1983. CO2 snow seems broadly feasible - although I am not sure that I would claim any climate implications - other than it is bloody cold in Antarctica.' You quote me out of context and imply a greater sigificance for a fun idea than it warrants. As I have explained - this is declining climate sensitivity to increasing greenhouse gases based on fundamental atmospheric physics. Bit of a shorthand - but I have tried to explain the concept. Are you saying this is wrong? There is no specific radiative forcing - just one forcing at one level of gases and another forcing at another - the relationship is not linear. -
David Horton at 10:49 AM on 16 July 2009Climate time lag
#75 "Does Thumb's post apply to the insistance that denialists are Christian and capitalists? " #62 "If it is a contest between God and capitalism and aetheism and socialism - I am on the side of the angels." -
Philippe Chantreau at 10:33 AM on 16 July 2009Climate time lag
"The freezing point of carbon dioxide is -57 degrees centigrade. The lowest temperature ever recorded was -89.2 at Vostok in 1983. CO2 snow seems broadly feasible" If you really believe this, then I know I have nothing to learn from you. The other statement I was referring to earlier was this one: "declining sensitivity to greenhouse gases" i.e. variable sensitivity to a specific radiative forcing. -
Robbo the Yobbo at 10:03 AM on 16 July 2009Climate time lag
Chris assumes that lack of increase in neutron count from 1953 implies that this does not correlate with increasing temperature. He essentially denies a 1150 year correlation based on half a century of observation. Utterly ridiculous. The true interpretation is that cosmic ray flux peaked in the last half of the 20th century on a 1000 year high at least. How should this translate into global energy storage. Solar irradiance changes very little – yet climate changes over 1500 year cycles. This has led to the pursuit of a GCR/Cloud connection to explain the discrepancy. The theory suggests a millennial low in cloud cover last century - but reasonably constant over period of the neutron record. As we have already seen, Chris confuses energy flux with energy – particularly as it accumulates in the ocean. The increase in shortwave radiation results in a radiative imbalance that takes some time to work through the system. See this Stanford University site for a far more balanced and considered discussion than is provided by blinkered global warmists. http://www2.slac.stanford.edu/vvc/cosmicrays/cratmos.html Contrary to the unscientific certainty of global warmists – this is not 100% certain. However, there are other cyclic processes that are far more certain. The planet is not warming for 20 to 30 years from 1998. -
Robbo the Yobbo at 09:47 AM on 16 July 2009Climate time lag
'What you said suggested that the climate was selectively reacting to different radiative forcings. AFAIK, there is nothing in the scientific litterature that could support that. A radiative forcing is a radiative forcing. Otherwise pointers would be appreciated.' What I said was: 'The point is that 0.08 degrees per decade (and declining sensitivity to greenhouse gases) is not sufficient to warrant restricting the economic aspirations of billions of people.' I am sure what I said implies that the climate response to a quanta of increase in greenhouse gases declines exponentially as gas concentrations increase. If we add x amount of greenhouse gases to the atmosphere there is y response. If we then add another x quanta - the response is less than y. Nothing magical about it. I very patiently explained the very basic atmospheric physics and suggested you look it up on Wikepedia. What is your problem? The EPA report is worth reading. I assume you haven't read it? I referred the the UAH temperature graph available on Roy Spencers website. It is also available on a NASA website. I have just had a look the Spencer CO2 blog. My first thought was - really 300 ppmv CO2 is background for an interglacial - but 380 ppmv is probably anthropogenic. I don't think Spencer claims to be convinced otherwise. Dr Roy Spencer has always been measured and rasonable. 'Roy W. Spencer received his Ph.D. in meteorology at the University of Wisconsin-Madison in 1981. Before becoming a Principal Research Scientist at the University of Alabama in Huntsville in 2001, he was a Senior Scientist for Climate Studies at NASA’s Marshall Space Flight Center, where he and Dr. John Christy received NASA’s Exceptional Scientific Achievement Medal for their global temperature monitoring work with satellites. Dr. Spencer’s work with NASA continues as the U.S. Science Team leader for the Advanced Microwave Scanning Radiometer flying on NASA’s Aqua satellite.' The freezing point of carbon dioxide is -57 degrees centigrade. The lowest temperature ever recorded was -89.2 at Vostok in 1983. CO2 snow seems broadly feasible - although I am not sure that I would claim any climate implications - other than it is bloody cold in Antarctica. Riccardo assumes that autocorrelation should be minimal - in fact it is the multi decadal signal in the data that is important, i.e. we are looking for the signal in the variation and not a period of approximately linear change. He assumes that the start and end points are arbitrary whereas they correspond to phase shifts in global climate as identified in the Swanson paper and as is evident in climate records. That is transitions in the mid 1940's, the mid 1970's and following 1998. He also assumes that variability is random noise whereas in fact it is temperature response to clouds, ENSO, volcanos etc. So in fact variation is meaningful and precision is limited only by the errors of measurement. 1998 is far from cherry picking - it was the end of one climate state and the beginnning of another. Very important. Swansons explanation is that the 1998 El Nino was so big it flipped climate into a new phase. I think clouds may be the driver - but feeding into a dynamic and resonant ocean and atmosphere. "But to be rabbiting on, at such length, about these minor matters, while the great big CO2 elephant in the room keeps trumpeting for attention, is a sign of the same old denialism that is based on an unshakeable ideology that either (or both), humans can't affect a god-given home; or unfettered capitalism based on an ever increasing dependence on burning fossil fuels is the only way to conduct human affairs" Does Thumb's post apply to the insistance that denialists are Christian and capitalists? I was trying to be relaxed and amusing on Riccardo's post. Perhaps I should have entered into a more serious statistical discussion. Nothing you are saying has any scientific content at all. -
Riccardo at 08:15 AM on 16 July 2009Climate time lag
Robbo, i have really nothing to comment on the torturing of data. It's just very basic statistics without which you can make the data tell you whatever you like. As infact too often happens. Swanson et al. identify the periods differently from you. "The top panel in Figure 1 shows that in a statistically rigorous sense such synchronizations only occurred four times (1910-20; 1938-45; 1956-60; and 1976-1981) during the 20th century, and three of those synchronizations (all but 1956-1960) coincided with shifts in the climate state." Hence, the period starting in '38-'45 ended in '75-'81. I started in 1970 but could have started in '75 or '81 as well, it makes no difference. Autocorrelations is progressivly lower the more you average. It does not depends on the time range but on averages. In monthly data (often quoted to "demonstrate" the cooling of the last decades) it's larger, lower for annual and even lower for longer averages. And yes, the variability is due to ENSO, volcanos, etc.; pretty random, isn't it? You could even check the degree of randomness and, what a surprise, it behaves pretty much similar to autocorrelation. But ... wait ... it's statistics again ... :D Anyway, if you have time to check, ENSO (MEI index) and volcanoes explain the great part of the fluctuations (almost all indeed) superimposed on a monotonic increase. Finally, 1998 is indeed your cherry picking. Swanson et al just hypothised that there has been a climate shift in 2000-'01 not in 1998. And it is just an hypothesis because they could not find any cause and the time span is too short. From Swanson's post on RealClimate: "Whether or not such a halt has really occurred is of course controversial (it appears quite marked in the HadCRUT3 data, less so in GISTEMP); only time will tell if it’s real." And I agree. Like it or not the last decade is still largely inside the natural fluctuations. -
shawnhet at 07:30 AM on 16 July 2009Climate time lag
Chris, "1. While we've been discussing minutae of the solar/cloud/climate response the obvious thing that I think we agree on is that there has been no significant secular trend in the cosmic ray flux (CRF) since detailed measures began in 1958. So the very large global scale warming of the last 30-odd years has nothing to do with the CRF." I don't really disagree here, I suppose though I think that there might be a trend vis a vis the GCRs. IAC, I don't think cosmic ray flux has been a major contributor to the short term temperature trends. What I find puzzling, however, is the complete lack of interest in the *long-term* correlation of CRF and climate events. Since I consider this long-term correlation to be pretty definitive, this influences my interpretation of short-term measurements as well. If I ignored the long-term correlation as you do, I might well come to the same conclusions as you. http://arxiv.org/PS_cache/arxiv/pdf/0804/0804.1938v1.pdf IAC, I can see a lot of reasons why relatively small and fairly short-term varations may not be easily seen(leading to contradictory answers being found by say Erlykin and Harrison). I cannot, however, think of a good reason why multiple long term analyses demonstrate a correlation in different time schemes and proxies, where a relationship does not actually exist. I further think that the analysis of climate issues is massively complicated and it is fairly easy for mistakes to be made. Given this, it is pretty easy to imagine that what seems true after reading one paper may not turn out to be accurate in the future. I think you are somewhat unfair to Svensmark and Shaviv, but there is no reason to keep beating that horse. I don't think there is anything particularily illogical about their arguments. I still submit that you are much too quick to rule out the link between the solar cycle and cloudiness(based perhaps on the most recent cycle contradictory data). I feel that this link is pretty well accepted (by Erlykin et al. certainly). There must be some way that sunspot counts get reflected in the price of wheat and I don't see how a 0.1-0.2 deg. C could do it. Cheers, :) -
Robbo the Yobbo at 07:29 AM on 16 July 2009Climate time lag
'What you said suggested that the climate was selectively reacting to different radiative forcings. AFAIK, there is nothing in the scientific litterature that could support that. A radiative forcing is a radiative forcing. Otherwise pointers would be appreciated.' What I said was: 'The point is that 0.08 degrees per decade (and declining sensitivity to greenhouse gases) is not sufficient to warrant restricting the economic aspirations of billions of people.' I am sure what I said implies that the climate response to a quanta of increase in greenhouse gases declines exponentially as gas concentrations increase. If we add x amount of greenhouse gases to the atmosphere there is y response. If we then add another x quanta - the response is less than y. Nothing magical about it. I very patiently explained the very basic atmospheric physics and suggested you look it up on Wikepedia. What is your problem? The EPA report is worth reading. I assume you haven't read it? I referred the the UAH temperature graph available on Roy Spencers website. It is also available on a NASA website. I have just had a look the Spencer CO2 blog. My first thought was - really 300 ppmv CO2 is background for an interglacial - but 380 ppmv is probably anthropogenic. I don't think Spencer claims to be convinced otherwise. Dr Roy Spencer has always been measured and rasonable. 'Roy W. Spencer received his Ph.D. in meteorology at the University of Wisconsin-Madison in 1981. Before becoming a Principal Research Scientist at the University of Alabama in Huntsville in 2001, he was a Senior Scientist for Climate Studies at NASA’s Marshall Space Flight Center, where he and Dr. John Christy received NASA’s Exceptional Scientific Achievement Medal for their global temperature monitoring work with satellites. Dr. Spencer’s work with NASA continues as the U.S. Science Team leader for the Advanced Microwave Scanning Radiometer flying on NASA’s Aqua satellite.' The freezing point of carbon dioxide is -57 degrees centigrade. The lowest temperature ever recorded was -89.2 at Vostok in 1983. CO2 snow seems broadly feasible - although I am not sure that I would claim any climate implications - other than it is bloody cold in Antarctica. Riccardo assumes that autocorrelation should be minimal - in fact it is the multi decadal signal in the data that is important, i.e. we are looking for the signal in the variation and not a period of approximately linear change. He assumes that the start and end points are arbitrary whereas they correspond to phase shifts in global climate as identified in the Swanson paper and as is evident in climate records. That is transitions in the mid 1940's, the mid 1970's and following 1998. He also assumes that variability is random noise whereas in fact it is temperature response to clouds, ENSO, volcanos etc. So in fact variation is meaningful and precision is limited only by the errors of measurement. 1998 is far from cherry picking - it was the end of one climate state and the beginnning of another. Very important. Swansons explanation is that the 1998 El Nino was so big it flipped climate into a new phase. I think clouds may be the driver - but feeding into a dynamic and resonant ocean and atmosphere. "But to be rabbiting on, at such length, about these minor matters, while the great big CO2 elephant in the room keeps trumpeting for attention, is a sign of the same old denialism that is based on an unshakeable ideology that either (or both), humans can't affect a god-given home; or unfettered capitalism based on an ever increasing dependence on burning fossil fuels is the only way to conduct human affairs" Does Thumb's post apply to the insistance that denialists are Christian and capitalists? I was trying to be relaxed and amusing on Riccardo's post. Perhaps I should have entered into a more serious statistical discussion. Nothing you are saying has any scientific content at all. -
nbrack at 06:58 AM on 16 July 2009Al Gore got it wrong
"The film said a sea-level rise of up to 20ft would be caused by melting of either west Antarctica or Greenland in the near future. The judge ruled that this was "distinctly alarmist" A 2007 report by the IPCC explained the maximum we can expect the sea level to rise is 1 foot 5 inches, alarmist indeed. http://www.youtube.com/watch?v=rImKRTBwXkc&feature=related This speaker holds similiar opinions in his book, and talks about the energy crisis, good video -
chris at 06:36 AM on 16 July 2009Climate time lag
Re #60, Shawnet Yes I suspect that this discussion has reached the end of the road. I'm going to summarize the conclusions as I see them. 1. While we've been discussing minutae of the solar/cloud/climate response the obvious thing that I think we agree on is that there has been no significant secular trend in the cosmic ray flux (CRF) since detailed measures began in 1958. So the very large global scale warming of the last 30-odd years has nothing to do with the CRF. It's worth re-emphasising this. After all on the blog page you referred us to, Shaviv asserts without evidence that cosmic rays "…does however explain most of the solar-climate link and a large fraction (perhaps 2/3's of the temperature increase over the 20th century)." Each of those sub-statements is a misrepresentation of scientific knowledge on these subjects (role of CRF in solar-climate link; role of CRF in 20th century temperature increase), as is readily apparent by looking at thr science, and it's worth being clear about the difference between what some people assert on blogs and what a dispassionate assessment of the scientific literature "says". 2. There's now substantial published analysis of CRF-solar cycle-cloud relationships. Early studies indicated a correlation between the CRF and the low cloud cover (LCC) component of the International Satellite Cloud Climatology Project (ISCCP) infra-red (IR) product during 1983 through 1994 (solar cycle 22) [Marsh and Svensmark, 2000]. Kristjánsson et al. (2002) extended the analysis through 2000, and showed that the correlation becomes poor after 1993. They also showed (i) that the correlation with the more reliable[*] ISCCP-IR/vis product was considerably poorer still, and (ii) that rather than correlating with the CRF, the correlation with the solar cycle seemed to match the irradiance changes rather than the CRF changes. This disconnect between CRF variation and LCC has become more apparent as time has progressed. 3. Svensmark and Shaviv have pretty much withdrawn from scientific analysis of these direct CRF-cloud relationships, advocating for their hypothesis from web blogs and web reports, while persuing other subjects (admirable basic physics of CRF effects on aerosol micro-nucleation; stellar winds and such like). In the meantime the ISCCP data has been extended to 2008, and two groups in particular have attempted to pull out the intricacies of any CRF-cloud/solar cycle-cloud relationships. 4. Each of these groups (Wolfendale/Sloan and Kristjánsson) have published several detailed analyses of possible solar cycle-CRF-cloud relationships (see references below), and have independently come to a similar conclusion. This is that any apparent correlation observed between the solar cycle and LCC changes arises from the irradiance component of the solar cycle and not the CRF component. Any LCC variation seems not to be a response to changes in the CRF. 5. Does LCC correlate with the solar cycle? The correlation is good during the early part of the ISCCP record (solar cycle 22) but the relationship begins to weaken around 1994, and the correlation from then to the present becomes progressively weaker. This is particularly apparent when the more reliable ISCCP-IR/vis product is used. There isn't much of a correlation between the solar cycle and ISCCP-IR/vis at all: one can inspect the ISCCP data from the ISCCP depository here: http://isccp.giss.nasa.gov/climanal7.html 6. For this reason, most analyses make use of just the period of solar cycle 22 (up to around 1994) and using the less reliable ISCCP-IR data, to investigate possible causal relationships. As indicated in [4.] above the evidence indicates any solar-cycle-LCC correlation isn't causal with respect to the CRF; apparent correlation between CRF and solar cycle seems to be an artefact of the fact that the CRF correlates with the solar cycle. 7. Direct empirical analysis of the CRF-LCC hypothesis therfore leads to the conclusion that there isn't a detectable causal link between CRF and LCC. However there may be a relationship between LCC and solar irradiance changes through the solar cycle. 8. Note that the two main advocates of the CRF-cloud-climate hypothesis don't address these subjects by doing relevant science, but either ignore these comprehensive analyses or snipe from web blogs. Ignoring the proper scientific channels and resorting to web blogs and web reports has the advantage for advocates that bogus arguments can be used to attempt to counter these analyses, and whenever a scientist might take the time to point out the errors on the blog, they can just be ignored. 9. Forbush events. Inconclusive so far. Some tenuous evidence that cloud cover might change in response to very large short term drops in the CRF. [*] according to the ISCCP scientists (Rossow and Schiffer, 1999), the ISCCP-IR/vis data is a more reliable product that the ISPCC-IR data set, since (i) IR cannot distinguish low clouds from any region of the earth's surface below that has trhe same temperature, and (ii) thin cirrus clouds can be misassifned as low level clouds. Rossow and Schiffer (1999) Advances in understanding clouds from ISCPP. Bull. Am. Met. Soc. 80, 2261-2287 Kristjánsson, J. E., A. Staple, J. Kristiansen, and E. Kaas, A new look at possible connections between solar activity, clouds and climate, Geophys. Res. Lett., 29(23), 2107, 10.1029/2002GL015646, 2002. Kristjansson JE, Kristiansen J, Kaas E (2004) Solar activity, cosmic rays, clouds and climate - an update Adv. Space Res. 34, 407-415. Kristjansson JE, Stjern CW, Stordal F, et al. (2008) Cosmic rays, cloud condensation nuclei and clouds - a reassessment using MODIS data Atmos. Chem. Phys. 8, 7373-7387. Erlykin AD, Sloan T, Wolfendale AW (2009) Solar activity and the mean global temperature Environ. Res. Lett: 4 art # 014006 Sloan T, Wolfendale AW (2008) Testing the proposed causal link between cosmic rays and cloud cover Environ. Res. Lett. 3 art. # 024001 A.D. Erlykin, T. Sloan, A.W. Wolfendale (2009) The search for cosmic ray effects on clouds J. Atmos. Solar Terrestr. Phys. 71, 955-958 A.D. Erlykin, G. Gyalai, K. Kudela, T. Sloan, A.W. Wolfendale (2009) Some aspects of ionization and the cloud cover, cosmic ray correlation problem J. Atmos. Solar Terrestr. Phys. 71, 823-829 -
Thumb at 03:36 AM on 16 July 2009Climate time lag
"You left one important, strong human ideological tendancy out." Nothing says Strong Science quite like inferring that your adversaries are communists. Heckofa rebuttal. Well played. -
Philippe Chantreau at 02:50 AM on 16 July 2009Climate time lag
What you said suggested that the climate was selectively reacting to different radiative forcings. AFAIK, there is nothing in the scientific litterature that could support that. A radiative forcing is a radiative forcing. Otherwise pointers would be appreciated. It also suggested that the response to a given forcing could vary, which would require much more elaboration (your post #66 vaguely describes how the forcing could vary, not the response). Perhaps it was just the wording leading me to interpret that way. However, I see nothing in your post #66 that I was not already aware of, nor anything that could definitely clarify your statement in #62. In my opinion, Riccardo is not torturing the data at all, he is using normal rules of statistical analysis. These rules apply for data in general, why would they not apply to temp. time series? Not paying attention to the residuals, autocorrelation, standard deviations would really be torturing the data. As for not trusting you, I see a number of reasons for that. You referred to blog postings by Spencer, who has clearly not a clue of what he does with his own maths on occasions. Spencer who has gone off the deep end with the CO2 cycle theories that he puts on the intertubes (but refrains to put up for peer-review). Those even scared "skeptics" on WUWT, a blog where it is considered acceptable to ponder whether or not Antarctica is cold enough to make atmospheric CO2 snow out of the air (seriously, they had a post on that, many thought it was plausible). That even these bozos would say Spencer should shut up on the CO2 cycle is telling, methinks. Also you cite that ridiculous (for a lack of a stronger word) EPA suppression story, which is such an empty pile of nonsense it's not worth discussing at all. Your insistence on cherry picking 1998 is no more reassuring. Thanks for the advice, but really, I'm safe. I'm not about to trust the Yobbo from the blog (albeit a better one) on any scientific matter. Nothing personal, I wouldn't really trust anyone else either. I form my own opinion. -
thingadonta at 19:34 PM on 15 July 2009Climate time lag
re61 David Horton "But to be rabbiting on, at such length, about these minor matters, while the great big CO2 elephant in the room keeps trumpeting for attention, is a sign of the same old denialism that is based on an unshakeable ideology that either (or both), humans can't affect a god-given home; or unfettered capitalism based on an ever increasing dependence on burning fossil fuels is the only way to conduct human affairs" You left one important, strong human ideological tendancy out. Socialist-determinism, the worst historical distorter of data on record. (eg eugenics, communism, race-based Nazism). I think some communist propaganda posters depict capitalism as a big elephant, but I don't know what they would have made of human-induced global warming... It is amazing, that just like Karl Marx, you just cant see the weaknesses and common disortions in your own side of the argument. (eg 1. Karl Marx was so blind he scoffed at the idea that factory managers would be tempted to distort/exploit the new 'economic system', not to mention the 'radical intellectuals' themselves- just like you seem to have trouble doing...) (eg 2. check out Pipes of Harvard Uni's book on Communism-who claims that communism was largely founded by radical intellectuals-just like the human induced C02 warming agenda) -
Robbo the Yobbo at 19:07 PM on 15 July 2009Climate time lag
Riccardo. You are torturing the data - up against the wall MF! Cheers Robbo -
Robbo the Yobbo at 19:01 PM on 15 July 2009Climate time lag
Philippe, This is simply a fundamental concept of atmospheric physics. Greenhouse gases are transparent to shortwave radiation and opaque to specific bands of infrared radiation depending on the gas. As there are already gases in the atmosphere - some of the radiation is already blocked. More gas doesn't linearly decrease transparency of the atmosphere to IR - rather the transparency exponentially declines with each additional molecule. Once the IR window is closed - no amount of addtional greenhouse gas will trap more IR - but we are not there yet. In fact, I once calculated what would happen to global temps if the IR window was closed completely (it's an engineering thing) - and I don't think we want to go there. It is why there is a quasi linear response to an exponential increase in greenhouse gases. Yes - climate does respond to anthropogeninc greenhouse gases - I'm just not sure what it is. The upper limit appears to be the trend between 1946 to 1998 rather than 1976 to 1998. This makes a difference between - oh hell - we are all going to die and we have some time for human technological capacity to make a difference. Instead we have all these people - including the UN - who are wildly exaggerating the threat - and they admit to that all the time - and saying they can solve the problem with more taxes and bigger government. Excuse me for being hyper skeptical. Trust me - I'm a scientist/engineer. No don't do that - look it up on Wikepedia. Cheers Robbo -
Riccardo at 18:43 PM on 15 July 2009Climate time lag
One need to be carefull before coming to conclusions from linear trends. Indeed, the choice of the time interval is not neutral and can not be chosen arbitrarly. Also, the natural variability needs to be taken into account. Luckly there are statistical criteria to be met. As for the first issue (the time interval) you need to look at the residuals and no trend must be present. You can also look at autocorrelation and be sure it is minimal. This criterion excludes both '50-'97 and '45-'98 intervals. This does not mean you can't use them but you cannot draw robust conclusions, just a rough average trend. Using GISS data and trying to go as far back in time as possible, I found the interval 1970-2008 consistenly linear with a trend of 0.165 +/- 0.014 °C/decade. As for variability, you need to calculate the standard deviation of the residuals and use the standard 2*sigma criterion (equivalent to the 95% confidence level). Doing this will make apparent that nothing has changed up to now (2008), all the data points are within the +/- 2*sigma interval. Also, the last decade is nowhere near an anomalous deviation from the trend. Before claiming that we are in period of cooling or even flat temperatures we need to wait until the anomaly drops consistenly outside the statistical significance range. Using the same data and range as before I found a natural variability (2*sigma criterion) of about +/- 0.2 °C. It's worth to notice that even using smaller intervals down to the last decade sigma remains unchanged and again all the points are within +/-2*sigma, including those commonly considered extremes. -
Philippe Chantreau at 17:55 PM on 15 July 2009Climate time lag
Robbo says "declining sensitivity to greenhouse gases" That implies that climate sensitivity is selective and variable, quite an interesting concept. References? -
Robbo the Yobbo at 14:50 PM on 15 July 2009Climate time lag
damn it - I meant 0.08 degrees per decade -
Robbo the Yobbo at 14:02 PM on 15 July 2009Climate time lag
This is just breaking – it appears that the underlying rate of warming between 1950 and 1997 was 0.1 degrees per decade. I would of (and have) used 1945 and 1998 – and get 0.08 degrees centigrade per decade. http://www.uwm.edu/~kswanson/publications/2008GL037022_all.pdf http://www.realclimate.org/index.php/archives/2009/07/warminginterrupted-much-ado-about-natural-variability/ Read carefully because Swanson supplies all necessary pre-digested rationalisations for global warmists. Although it is not new or startling science it is capitulation to the bleeding obvious. http://rogerpielkejr.blogspot.com/2009/07/two-decades-of-no-warming-consistent.html I am content to leave open the question of whether this is a longer term trend. The point is that 0.8 degrees per decade (and declining sensitivity to greenhouse gases) is not sufficient to warrant restricting the economic aspirations of billions of people. RealClimate states that this is not global cooling (at least not following the next decade or so) but natural variation - due to globally synchoised sea surface temperature changes triggering climte shifts over 20 to 30 years - on a warming trend. Has anyone argued that we can keep increasing carbon dioxide emissions. Certainly people like Bjorn Lomberg argue for an economically and technologically rational transition that doesn’t put millions of lives in the developing world at risk. And yes – stable democracy and a minimally regulated capitalism is the only way billions of people will emerge from poverty this century – although this would be more a policy than a science thread. So David, stop putting words in my mouth. If it is a contest between God and capitalism and aetheism and socialism - I am on the side of the angels.
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