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Comments 131651 to 131700:

131651. leebert at 15:45 PM on 15 June 2008
        Arctic sea ice melt - natural or man-made?
        Chris: Soot's role in the Arctic has been widely discussed since 2001, so yes, it's not really news. Except that the environmental activists do not mention it, they do not want a discussion on soot to divert attention from CO2. So what if two of the top researchers in the field are in agreement about the efficacy of soot mitigation in at least slowing the boreal thaw? What if we can't abate CO2 fast enough to forestall any warming that poses any real risk? Or what if CO2's future effects aren't as profound as the worst-case forecasts? In both cases failing to mitigate soot would be a huge error. So yes, it's been swept - politically - under the rug. And it stinks. And as for the net warming from tropospheric soot (Ramanthan, Carmichael, 2008) their study shows that worldwide - across the vast Pacific basin and elsewhere - soot in conjunction with sulfates are not *masking* CO2's warming effect, they are in fact "enhancing it." That's a very nice way of saying aersols have falsely IMPLICATED CO2 by a 35% margin. Both Ramanathan *AND* Carmichael have conceded that the presumed cooling effect of aerosols in the 1970's is only a popular guess and could well be wrong. As early as 2001 researchers have been citing warming anomalies in the Asian Brown Clouds. In 2003 Ramanathan's INDOEX work got spanked by the IPCC at the behest of the Indian & Chinese gov'ts. So again, it *has* been swept under the rug. And it stinks.
131652. chris at 08:26 AM on 15 June 2008
        Arctic sea ice melt - natural or man-made?
        leebert, a paper cited a couple of times on this thread highlights all of the forcings including those from black carbon, so the soot isn't being swept under the carpet! i.e.: Hansen et. al. (2005): Earth's energy imbalance: Confirmation and implications. Science, 308, 1431-1435 http://pubs.giss.nasa.gov/docs/2005/2005_Hansen_etal_1.pdf (see Figure 1) (and see updated version below [***]; Figure 5 on page 26} The soot (black carbon) seems to be a little complex. McConnell et al [*] published data from Greenland ice cores that show that by far the greatest effects of black carbon on Artic ice occurred in the period rising from around 1900 to 1930, and then dropping back down to low levels by 1950, with occasional pulses (due to forest fires) from then. So the dominant effects of black carbon on Arctic ice albedo were in the early to mid 20th century, and perhaps that was a significant contribution to the Arctic warmth in the early part of the 20th century. The median estimated surface forcing (during early summer) was around 0.42 W/m2 before 1850, and was around 1.13 W/m2 in the period 1850-1951, with values as high as 3.2 Wm2 in the early 20th century. It’s been around 0.59 W/m2 since 1951 to present. [*] J. R. McConnell et al (2007) 20th-century industrial black carbon emissions altered arctic climate forcing; Science 317, 1381-1384. Albedo effects of black carbon on snow/ice seem rather more problematic for the Himalayas/Tibetan plateau/NE China regions (consistent with a dominant source for black carbon in Asia), where black carbon albedo forcings can reach 4.5 W/m2. [**] [**] J. Ming et al (2008) Black carbon record based on a shallow Himalayan ice core and its climatic implications; Atmospheric Chemistry And Physics 8, 1343-1352. Hansen et al (2007) estimate a contribution of black carbon/ice albedo effects of 0.065 oC to total global warming since the start of the industrial age [***]. This would obviously be larger locally (where the snow/ice is!), but the albedo effects act only during part of the year and at least for the Arctic were predominant in the period up to the 1950’s (see [*]). [***] Hansen, J et al. (2007) Climate simulations for 1880-2003 with GISS modelE. Clim. Dynam., 29, 661-696. http://pubs.giss.nasa.gov/docs/2007/2007_Hansen_etal_3_small.pdf Everyone agrees that it would be good if ice albedo-reducing black carbon could be eliminated, as a means of slowing down the effects of greenhouse-gas-induced warming: e.g.: [“Arctic warming is primarily a manifestation of global warming, such that reducing global-average warming will reduce Arctic warming and the rate of melting (IPCC 2007). Reductions in the atmospheric burden of CO2 are the backbone of meaningful efforts to mitigate climate forcing. But even if swift and deep reductions were made, given the long lifetime of CO2 in the atmosphere, the reductions may not be achieved in time to delay a rapid melting of the Arctic. Hence the goal of constraining the length of the melt season, and, in particular, delaying the onset of Spring melt, may best be achieved by targeting shorter-lived climate forcing agents, especially those that impose a surface forcing that may trigger regional scale climate feedbacks pertaining to sea ice melting.”] [****] [****] Quinn, P. K. et al (2007) Short lived pollutants in the Arctic-their climate impact and possible mitigation strategies. Atmos. Chem. Phys. 8, 1723-1735. The situation seems complicated by the fact that different sources of soot can have different directions of forcing, and the total aerosol load is actually protecting us somewhat from the full effects of greenhouse-gas induced warming. So (referring to Figure 28 in Hansen et al (2005) [*****; note that Hansen’s papers are useful since they’re freely downloadable!]), soot from fossil fuel burning has a positive (warming) forcing whereas soot from biomass burning has a negative (cooling) forcing, apparently. Non-soot aerosols provide a strong negative cooling forcing. The total effect of soot on global warming seems to be about nett neutral worldwide (‘though presumably net positive in regions with snow). So it seems one would have to be rather careful to eliminate just those components of the aerosol burden that gives rise to positive forcings. [*****] Hansen, J. et al. (2005) Efficacy of climate forcings; J. Geophys. Res., 110, D18104 http://pubs.giss.nasa.gov/docs/2005/2005_Hansen_etal_2.pdf The following paper also seems relevant; however it’s very dense! It’s a modelling paper and seems to be general in accordance with those cited above. M. G. Flanner et al (2007) Present day climate forcing and response from black carbon in snow; J. Geophys. Res. 112, D11202 The more specific question of the contribution of black carbon to Arctic sea ice recession seems difficult to hunt down. Note than the guy in your press release (Zender) is an author on both Flanner et al (2007) just above, and paper [*]. He seems to suggest that it’s around 33% now….however I haven’t found a clear-cut analysis in a published paper. That’s not to suggest there isn’t one!
131653. chris at 06:08 AM on 15 June 2008
        Arctic sea ice melt - natural or man-made?
        No that's wrong again, Quietman. You should read the papers that you dump before dumping them. And considering that we were discussing Arctic sea ice, and Fairbridge and Mackey, and aerosol contributions and volcanism and so on, I don’t really understand the point of changing the subject with these papers. In any case, neither of them says much that is against the mainstream science; Tung and Camp, especially, is completely in accordance with the scientific determination of the Earth’s equilibrium temperature response to manmade enhancement of the greenhouse effect (enhanced [CO2]!). Tung and Camp attempt to tease out the solar cycle contribution to the Earth's surface temperature. Obviously as the sun goes through its solar cycle (a complete "warming-cooling-warming" cycle every 11-ish years), the Earth must respond to some extent. Tung and Camp suggest that they can pull out a temperature variation of 0.018 oC between the solar minimum and maximum. That's a little larger than others find (~ 0.1 oC), but obviously the Earth's surface temperature must respond a little to the small change in solar output during the solar cycle, even if this response at the surface is damped (relative to the tropospheric response, for example). But there's nothing too remarkable about that and the paper neither particularly "supports natural forcing" nor does it "question the effect of AGW". In fact it completely supports the latter. Tung and Camp use their data to determine an independent measure of the Earth's "climate sensitivity". This is 2.3 - 4.1 oC per doubling of atmospheric [CO2] at 95% confidence. That's pretty much exactly what everyone else finds, and is pretty much exactly what I said earlier on this thread (e.g. 3 oC +/- a bit; see my post #12). In other words Tung and Camp are completely mainstream about AGW. They consider that manmade enhancement of the Earth's greenhouse effect causes warming equivalent to around 3 oC (2.3 - 4.1 oC at 95% confidence) per doubling of atmospheric CO2 (or CO2 equivalents). They support the conclusion that the fact that we've been near, or at the bottom of the solar cycle for the last couple of years, is a significant contribution to a temporary slow down of greenhouse-induced warming, and that as the solar cycle heads upwards through the next 5 or 6 years, the solar cycle effect will be adding to the greenhouse effect for a while, rather than countering it. There's nothing surprising there. We already know that. To spell out the obvious: Continual enhancement of the Earth's greenhouse effect produces a rather persistent, unidirectional increase in the Earth's surface temperature as the climate system tries to equilibrate at an ever-increasing greenhouse forcing. On top of this is a cyclic contribution (warming-cooling-warming-cooling) from the solar cycle. So the AGW greenhouse temperature forcing is “positive…positive…positive…”, whereas the solar cycle gives “positive…negative…positive…negative…positive” in a nice sinusoidal cycle (net contribution over the last 50 years pretty close to zero). In general we would look at the temperature record and consider that we can't really "see" the solar cycle contribution: e.g. http://data.giss.nasa.gov/gistemp/2007/ Tung and Camp consider that they can "tease it out"....fine!... The Scafetta and West paper is a mathematical analysis of the historical solar irradiance record in which a phenomenological (i.e. theoretical/empirical) possible solar contribution to 20th century warming under the assumption that all temperature variations in a (pre-industrial) test period were solar-induced. They suggest that in this theoretical analysis the sun "might" have contributed "approximately" "up to" 50% of 20th century warming. Fair enough. The sun "might" have contributed anywhere from zero to 50% of warming. We know that the sun has made no significant contribution to the marked warming of the last 30-odd years...we are pretty sure that the sun made some contribution to the warming in the early part of the century. Perhaps the solar contribution was 10-20% of 20th century warming, largely focussed in the period 1900-1940ish. I don't think anyone would quibble with that either. It’s a statistical/mathematic exercise. The authors are suitably circumspect about the nature of their phenomenological conclusion.
131654. Quietman at 03:57 AM on 15 June 2008
        Arctic sea ice melt - natural or man-made?
        Phillippe and chris Here are the abstracts from two recent papers that support natural forcing and question the effect of AGW. Solar-Cycle Warming at the Earth’s Surface and an Observational Determination of Climate Sensitivity. By Ka-Kit Tung and Charles D. Camp Department of Applied Mathematics, University of Washington, Seattle Washington, USA The total solar irradiance (TSI) has been measured by orbiting satellites since 1978 to vary on an 11-year cycle by about 0.07%. From solar min to solar max, the TSI reaching the earth’s surface increases at a rate comparable to the radiative heating due to a 1% per year increase in greenhouse gases, and will probably add, during the next five to six years in the advancing phase of Solar Cycle 24, almost 0.2 °K to the globally-averaged temperature, thus doubling the amount of transient global warming expected from greenhouse warming alone. Deducing the resulting pattern of warming at the earth’s surface promises insights into how our climate reacts to known radiative forcing, and yields an independent measure of climate sensitivity based on instrumental records. This model-independent, observationally-obtained climate sensitivity is equivalent to a global double-CO2 warming of 2.3 -4.1 °K at equilibrium, at 95% confidence level. The problem of solar-cycle response is interesting in its own right, for it is one of the rare natural global phenomena that have not yet been successfully explained. Phenomenological reconstructions of the solar signature in the Northern Hemisphere surface temperature records since 1600 N. Scafetta1 and B. J. West2 Received 18 January 2007; revised 4 May 2007; accepted 5 June 2007; published 3 November 2007. A phenomenological thermodynamic model is adopted to estimate the relative contribution of the solar-induced versus anthropogenic-added climate forcing during the industrial era. We compare different preindustrial temperature and solar data reconstruction scenarios since 1610. We argue that a realistic climate scenario is the one described by a large preindustrial secular variability (as the one shown by the paleoclimate temperature reconstruction by Moberg et al. (2005)) with the total solar irradiance experiencing low secular variability (as the one shown by Wang et al. (2005)). Under this scenario the Sun might have contributed up to approximately 50% (or more if ACRIM total solar irradiance satellite composite (Willson and Mordvinov, 2003) is implemented) of the observed global warming since 1900. Citation: Scafetta, N., and B. J. West (2007), Phenomenological reconstructions of the solar signature in the Northern Hemisphere surface temperature records since 1600, J. Geophys. Res., 112, D24S03, doi:10.1029/2007JD008437.
131655. Philippe Chantreau at 02:15 AM on 15 June 2008
        Arctic sea ice melt - natural or man-made?
        And that soot is man-made, is it not?
131656. leebert at 22:15 PM on 14 June 2008
        CO2 lags temperature
        

        “As Congress prepares to debate new legislation to address the threat of climate change, opponents claim that the costs of adopting the leading proposals would be ruinous to the U.S. economy. The world’s leading economists who have studied the issue say that’s wrong”

        The world's leading economists? Have they mentioned the imbroglio brewing over in Europe, the ongoing rebellion in Britain? In the EU the Europeans are looking at their carbon tax overheads and realizing that they could lose their steel firms to Asian steel makers. This is b/c of the market-distorting effect of carbon taxes levied on developed nations that are not levied on developing ones. In England the additional green taxes saw "Red Ken" get ousted from the mayoral seat of London, where Ken Livingston saw the election as largely a green referendum. It was alright, an anti-green one. Labour is hammering Brown to relinquish some of the additional green taxes on trucking firms, etc. Only three countries in Western Europe have met their Kyoto targets, Sweden & France using nuclear power and Switzerland from hydro. And Japan - one of the most energy-efficient countries in the world - has simply said it cannot afford the Kyoto targets.
131657. leebert at 22:06 PM on 14 June 2008
        CO2 lags temperature
        

        John, I've tried to understand how the paleo ice records are anything more than anecdotal. Problem is I've seen counterveiling studies that show that light oxygen - a direct proxy for water vapor - shows a more-consistent correlation with paleo temperatures than CO2. The ice ages hit an arid maximum and the thaws always saw a large increase in humidity as ice-locked water was returned to the hydrological cycle. It makes sense that CO2 played a role in the interglacials but the discontinuities I see in the record seem to disprove an absolute temperature-driving record for CO2. I mentioned the same thing on Watts' blog:

        Take a look at this Vostok ice core: http://www.ourworldfoundation.org.uk/IceCores1.gif The CO2 levels associated with past interglacials is 180 to 300 ppm, well below where we are now. 325 kya when CO2 went from 200 to 310 ppm, what did the temperature trend show? It shot up 3 or more degrees, didn’t it? The problem is that contemporary CO2 levels were already at 280 ppm during the Little Ice Age and have risen to 385 ppm; however, we’ve yet to see any hint of an equivalent temperature trend, not even latent heat in the seas (oh sure, there’s some, but it’s not piling up at the rate predicted). OTOH look at this chart: Light oxygen, isotopic Oxygen-16 is used to reconstruct paleoclimate b/c glaciers lock up light oxygen and reaches a minimum as ice ages reach an arid maximum. image006.jpg If you superimpose the light oxygen data (flip & stretch) over the past 200ky, (that’s easy to do even with MS Paint) you’ll see that the light oxygen trend line matches more closely to the paleo temperature trend than does the paleo CO2 trend where CO2 & temperatures periodically slip out of tight correlation (between 80 - 110kya and 160 - 180 kya). http://i29.tinypic.com/28iyro8.jpg ( superimposition of the light oxygen chart over the vostok chart). Eyeball analysis time: There are two discontinuities between CO2 & temperature that aren’t discontinuities between Light Oxygen and temperature. Can you see the point? B/c of its evaporative and water-forming nature, light oxygen availability is a direct reflection of water vapor concentration in the atmosphere. So what’s the dominant driving agent? Is it CO2? Is it water vapor? This is why climate agnostics aren’t won over by the pro-AGW paleoclimate studies, they seem anecdotal. If CO2’s effect were consistently strong (and it’s causes steeper temperature changes at lower concentrations) then temperatures would follow more closely to the CO2 line, but they don’t, temperatures follow the water vapor line (and vice versa). What CO2 effect there is is inconclusive. CO2 may play a role, but it isn’t dominant throughout the paleo record. Just b/c it correlates doesn’t mean it causates. Our current 380 ppm CO2 level isn’t reflected by the paleo data, contemporary CO2 levels have surpassed the level of spectral absorption that has been claimed to have caused that much warming in the paleo record. And the more CO2 is added to the air, the less additional effect it has in a trend of progressively diminishing returns. Something’s inconsistent with the theory that CO2 drives temperatures.

131658. leebert at 21:54 PM on 14 June 2008
        Arctic sea ice melt - natural or man-made?
        I'm surprised no one mentioned the role of albedo loss to dirty snow from soot deposition: Here: http://www.scientificblogging.com/the_soot_files/soot_black_icebergs_and_arctic_ice and: http://www.sciencedaily.com/releases/2006/03/060319183843.htm Soot is the carbon that must not be named....
131659. chris at 05:30 AM on 14 June 2008
        Arctic sea ice melt - natural or man-made?
        You didn’t answer the question, Quietman. You linked to an article by one Richard Mackey (no scientific publications whatsoever on climate/solar-related topics – has he published any science?). This is a poor and unscientific piece of work in which Mackey copies stuff out of press releases [*], makes demonstrably incorrect assertions [**], misrepresents entire scientific fields by selective citation (“cherrypicking”) [***], and pursues a false description of the mainstream scientific view of solar contributions to climate [****] (see bottom of post for examples). Mackey cites only one relevant (to solar cycles and climate effects) scientific paper of Fairbridge (we can leave out the fine papers on sea levels, and the various book chapters that he cites). This is: FAIRBRIDGE, R.W. and SHIRLEY, J. H., 1987. Prolonged Minima and the 179-yr cycle of the solar inertial motion. Solar Physics, 110 191-220. I’ve read this just now. It’s a perfectly fine piece of work, and I’m surprised you feel reluctant or unable to summarize Fairbridge’s hypothesis, or to cite his relevant papers. However it highlights fundamental problems with your description of Fairbridge’s hypothesis as being “the best explanation to date for climate change”. Here’s two: (i) Fairbridge and Shirley’s (F&S) analysis applies strictly to solar minima. In other words periods of “abnormally” low solar output, as identified by sunspot number for example. So in their Figure 5 they plot their measure of solar output as a function of time, and overlay with shading, periods of low sunspot number (these correspond to the well-known Wolf, Sporer, Dalton minima). But that’s it. F&S’s analysis has nothing to say about periods of global warming. The sun is either in a “normal” state or it is in one of its periodic minima. Fairbridge’s hypothesis (at least as outlined in F&S) has nothing to say about the very large global warming of the last 30-odd years, let alone the dramatic attenuation of Arctic sea ice since the 1960’s. That should be the end of the story as far as the subject of this thread is concerned. We know full well that changes in solar outputs have made little contribution to warming of the last 30-odd years, so we can leave Fairbridge’s nice work out of a discussion of causal factors relating to dramatic Arctic sea ice attenuation. However F&S make a prediction for the next minimum and it’s interesting to see how this might work out: (ii) On their Figure 5 F&S also shade a period corresponding to a prediction (made tentatively) for the next minimum. The next period of abnormally low sunspot numbers starts near 1990 and goes to 2020 (the latest date of their analysis - although they suggest the next minimum will be more prolonged). We can test at least the early part of this prediction since we have access to the sunspot numbers, e.g. here: http://en.wikipedia.org/wiki/Sunspot or: http://www.spaceweather.com/java/archive.html (etc.) Clearly we haven’t been in a low sunspot number phase since 1990. In fact sunspot numbers have been very high throughout cycle 22 (peaking near 1991), and high throughout cycle 23 (peaking near 2002). We don’t know what is going to happen very far into the future. However geomagnetic activity seems to be a very good predictor of subsequent sunspot cycle activity, and cycle 24 due to peak near 2013, is predicted to be a high sunspot number cycle: http://science.nasa.gov/headlines/y2006/21dec_cycle24.htm although others think it will be weaker: http://www.lund.irf.se/rwc/cycle24/ Now maybe the sun will enter a period of prolonged reduced output. But so far it hasn't, and the marked recent warming was entirely independent of the analysis/hypothesis of Fairbridge anyway. -------------------------------------------------------- some deficiencies in Mackey's eulogy of Fairbridge that you linked to in your post #15 [*] I was interested to read what Mackey had to say about sea levels, and this odd non-sciency sentence jumped off the page (see top of second column on page 961), referring to Baker’s work on sea level fluctuations): [“ BAKER et al (2005) have been collaborating on the project for the past eight years and have published nine papers in scientific journals in relation to it.”] That seems an odd thing to say in a scientific paper, so had a look to see whether it might be a “second hand” statement. It’s copied out of a press release. Here’s the sentence from the press release: http://www.une.edu.au/news/archives/000327.html [“The UNE scientists, Dr Baker, Dr Robert Haworth and Professor Peter Flood - have been collaborating on the project for the past eight years and have published nine scientific papers in international journals.”] …and examination of the previous paragraph of Mackey’s article shows more of this low grade plagiarism that is characteristic of the lazy or poorly-informed. [**] The following section from page 961 (bottom of left hand column). I’ll leave the reader to consider whether this has any merit: [“As SCAFETTA and WEST (2006b) report, increased solar activity warms the oceans, increases the volume of water vapour and carbon dioxide in the atmosphere and reduces the oceans’ uptake of water vapour and carbon dioxide from the air. As a result, some of the atmospheric carbon dioxide that has been attributed to human activity may have a solar origin. The resultant release of more water vapour and carbon dioxide into the atmosphere may have contributed to the warming that is already the direct result of increased solar output, variations in the sun’s gravitational force and interactions between the two. It is to be hoped that in its next series of publications the IPCC will quantify the proportion of greenhouse gases that have been produced by the sun in this manner.”] [***] Cherrypicking is rampant throughout Mackey’s article: Since I was surprised to read of Mackey’s assertions about late Holocene sea level variations: [“…even within the past thousand years, there have been several sudden changes in sea levels of up to two metres. The UNE team has discovered that each of these large changes took less than 40 years from beginning to end.”] I had a read of Richard Bakers paper (very nice too), but also some of the more recent analyses of Holocene sea level changes (e.g. Lewis et al 2008). It turns out that Baker’s work is only one of many studies of late Holocene sea levels, and that in general the evidence for large variations in Holocene sea levels are not well-supported. In fact Sloss et al (2007) indicate that Baker’s very large apparent fluctuations relate to their method (parapharising) of 14C-dating marine organisms found at various heights above present mean sea level, and assuming that defines the sea level height at the time identified by the 14C date, without making corrections for possible changes in tidal ranges, wave climate and so on. Whatever the final story on this, Mackey gives an entirely false representation of the subject by focussing on one piece of work that supports his “thesis”. S. E. Lewis et al (2008) Mid-late Holocene sea-level variability in eastern Australia; Terra Nova, Vol 20, No. 1, 74–81 C. R. Sloss et al (2007) Holocene sea-level change on the southeast coast of Australia: a review; The Holocene 17; 999-1014. [****] This can be stated succinctly. Mackey pursues the tired fallacy of pretending that because mainstream science shows no significant role for changes in solar outputs in the very marked warming of the last 30-odd years, that mainstream science (and the IPCC!) are ignoring the sun and downplaying it’s role as an influence on the Earth’s climate.
131660. Lee Grable at 02:01 AM on 14 June 2008
        Global warming stopped in 1998, 1995, 2002, 2007, 2010, ????
        If the La Nina is moving cooler water to the surface, then it stands to reason that warmer waters are moving to the depths. Is there a flaw in my reasoning?
131661. Philippe Chantreau at 01:53 AM on 14 June 2008
        Arctic sea ice melt - natural or man-made?
        There is nothing circular about this. The lack of publication clearly indicates that the "hypothesis" has not been scientifically investigated. Perhaps it deserves to be but as of now, there is no work in support of it. I don't see that you provided proof to the contrary anywhere in this thread. If you really have cites, present them. But once again, the Mackey paper is not a real paper. Do you also have an explanation as to why the hypothesis has failed to generate enthusiasm among planetary scientists and specialsts of the Sun?
131662. leebert at 00:59 AM on 14 June 2008
        Global cooling: the new kid on the block
        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!
131663. Quietman at 16:53 PM on 13 June 2008
        Arctic sea ice melt - natural or man-made?
        Philippe I did that. I answered the question. I refuse to argue with circular logic.
131664. Philippe Chantreau at 16:29 PM on 13 June 2008
        Arctic sea ice melt - natural or man-made?
        You're trying to evade Chris' questions Quietman. It is common on this site to provide links to science papers. Why don't you give links to peer-reviewed science papers pertaining to solar/planetary inertia/gravitation and their influence on the Earth's climate? If Mackey's paper is not a peer-reviewed science paper, it does not carry the weight that you attribute to it. What else is there? This: "If those models were correct the warming should have continued at the same or higher rate but in fact it did not, proving the models to be invalid." You seem to suggest that all noise should disappear from the natural system in order for the model to be valid. I don't think that's how it works.
131665. Quietman at 03:11 AM on 13 June 2008
        Arctic sea ice melt - natural or man-made?
        chris You appear to have a fundamentalist problem with reading comprehension - so I give up.
131666. chris at 19:49 PM on 12 June 2008
        Arctic sea ice melt - natural or man-made?
        Quietman, re Fairbridge and his "hypothesis". I was surprised to read in your post #17, the comment: "BTW - Thanks for the 2005_Hansen_et. al. link. A little dated but interesting. No problem, btw! However I'm surprised you consider a 3 year old paper "a little dated". Since I didn't know of Fairbridge's theories before yesterday I had a look for his scientific publications in the database. I can't find any scientific paper by Fairbridge in the last 10 years on the subject of solar influences on climate. So everything by Fairbridge is "a little dated" (certainly so in relation to Hansen's paper published in 2005!) Fairbridge published a brief report in 1995 that seems related to this topic: Fairbridge RW, Haubold HJ, Windelius G (1995) "Potential of interplanetary torques and solar modulation for triggering terrestrial atmospheric and lithospheric events" Earth Moon and Planets 70 179-181. but clearly a "hypothesis" can't be fully expounded in 3 pages, and this brief paper has been cited only once in the last 13 years, and clearly hasn't made any impact in the field. His next "most recent" paper that relates to this subject seems to be: Shirley JH, Sperber KR, Fairbridge RW (1990) Suns inertial motion and luminosity; Solar Physics 127, 379-392. (18 years old; 5 citations in 18 years). ...and so on...so everything by Fairbridge seems "a little dated". The article that you linked to by Mackey isn't a scientific paper. It's a eulogy of Fairbridge by some statistician who hasn't published any science on climate change, and who uses his article to pursue the political argument that we shouldn't do anything about the problem of global warming, but should just carry on, let things take their course, and "adapt" ("Adaptive efficiency is the key"!). I would like to see the relevant articles by Fairbridge himself in which his "hypothesis" is expounded. Can you cite these? Let Fairbridge's work speak for itself! I would also like to see a description from you of the mechanisms by which the "hypothesis" of Fairbridge explains the marked attenuation of Arctic sea ice since the 1960's, and the massive excess attenuation of sea ice in the summer of 2007, and so on. After all, it's not very scientific to refer to some unspecified "hypothesis" as a "catch-all" explanation of everything climate-related (you said in post #13: "Thus far the cycles of the solar system's gravitational forcing has been the best explanation to date for climate change"), without explaining what this "hypothesis" is, and illustrating specifically how it pertains to the issue at hand (i.e. the attenuation of Arctic summer sea ice).
131667. chris at 18:05 PM on 12 June 2008
        Arctic sea ice melt - natural or man-made?
        Re #20, Quietman Actually Kay et al (2008) didn't say it was natural. That's very clear from a reading of Kay et al. (2008) as outlined in detail in my post #8. John Cook's top article gives a good account of the view that is supported by the scientific evidence. You didn't explain why CO2-induced AGW can't have caused the thinning. You made some vague comments about roles for water vapour, solar brightening from reduced aerosols and vulcanism. However each of these is unsupportable by the scientific evidence (see my post #12). The very paper that you brought to our attention apparently to "support" your assertion about reduced aerosol load, actually shows the opposite (see my post #19). That's not skepticism... You talk about "proving" that AGW exists. But of course in science "proof" isn't really a helpful concept ("proof" is a mathematical/philosophical concept). The scientific evidence strongly supports the conclusion that massive release into the atmosphere of greenhouse gases sequestered from the short term carbon cycle for many millions of years, results in warming of the Earth's surface. The warming we've seen and the distribution of excess heat, and so on is entirely consistent with expectations. And we can understand the dramatic attenuation of Arctic sea ice in relation to long term greenhouse forcing (especially since the 1960's following widescale post-war industrialisation), with a large additional factor (increased LW downwelling amplified by albedo effects) resulting in a sharp increased melting during the summer of 2007. Notice that the assumptions of AGW have got virtually nothing to do with models. Notice also that there is no expectation within the well-supported phenomenon of greenhouse-induced warming that the Earth's surface temperature should increase monotonously each year, nor that the Earth's surface might not cool for a bit within a warming scenario, and so on. To make such assertions is to misrepresent the scientific evidence and its interpretations, and that also is not skepticism. If one needs to bring "Young Earth fundamentalists" into it, I suspect one really doesn't have an argument!
131668. Quietman at 13:06 PM on 12 June 2008
        Arctic sea ice melt - natural or man-made?
        PS I already gave you the link to mackey's paper which gives the explanation of the hypothesis. Google Rhodes-Fairbridge and you can find his ideas quite easily. I do not remember where I found them anymore and he won't respond to e-mails. He died two years ago.
131669. Quietman at 12:59 PM on 12 June 2008
        Arctic sea ice melt - natural or man-made?
        chris Actually I agreed with Kay et. al. 2008, in that it was natural. I disagreed with AGW being the cause of the thinning and explained why. In order to blame it on CO2 induced AGW you first have to prove that it exists and then you have to prove exactly what part of warming it causes. Hypothetically it should warm the poles first. But the same is true of the alternate hypotheses. The papers I have read on AGW are very interesting but make too many assumptions based on poor climate models. If those models were correct the warming should have continued at the same or higher rate but in fact it did not, proving the models to be invalid. The burden of proof is on the writer, not the writer's skeptics. That is how science works regardless of how the younger generations might like to change it. The Young Earth fundamentalsts do the same thing, make an assumption (age of the earth) and disprove any argument with that assumption. Not acceptable. We are talking about a hypothesis, not even a theory, far from being proven and getting farther every year for the past 10 years.
131670. chris at 08:00 AM on 12 June 2008
        Arctic sea ice melt - natural or man-made?
        Quietman, the Stjern et al paper in press that you url in your post #17 is pretty much consistent with my statement in post #12 concerning aerosols and solar irradiation reaching the surface (global "dimming"/"brightening"). I said: [[(ii) "solar brightening from lack of aerosols". Nope. The atmospheric aerosol load has increased rather significantly since the 1960's. Thus enhanced Arctic sea ice melt has increased despite the overall decreased solar irradiation reaching the surface. Rather than "solar brightening" we've actually had a bit of "solar dimming". e.g. see: Hansen et. al. (2005): Earth's energy imbalance: Confirmation and implications. Science, 308, 1431-1435 (see Figure 1). http://pubs.giss.nasa.gov/docs/2005/2005_Hansen_etal_1.pdf]] Which is what Hansen et al show in their 2005 paper concerning the contributions to the Earth's energy budget in the 20th century. In other words the atmospheric aerosol load has increased rather significantly since the 1960's. Likewise that's what Stjern et al show indirectly. If you look at their Figure 3, which is a composite of the surface solar irradiation combining data from 11 stattions in the high Northern latitudes (see page 25 of the manuscript that you linked to), the surface solar irradiation was around 115 Wm-2 in 1960 (somewhat higher earlier), and is around 107 Wm-2 at the end of Stjern et al's measuring period. In other words the rather persistent attenuation of Arctic sea ice (the subject of this thread!) under the influence of marked global warming since the 1960's[***] has occurred even while the surface solar irradiation has decreased due to an enhanced atmosperic aerosol load. [***]http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/seasonal.extent.1900-2007.jpg
131671. chris at 07:33 AM on 12 June 2008
        Arctic sea ice melt - natural or man-made?
        Quietman, you're wandering way away from the subject of this thread which is the massive attenuation of Arctic sea ice during the summer of 2007. Straightforward scientific analysis provides a self-consistent interpretation in terms of global warming resulting from enhancement of the Earth's greenhouse effect through massive greenhouse gas emissions (this has been the cause of the relentless attenuation of Arctic summer sea ice since the 1960's - see urls in my posts above), together with weather conditions (reduced cloudiness and increased solar LW downwelling) that are normally rather neutral in their effects on Arctic sea ice extent, but under conditions of greatly denuded sea ice, result in rather significant melting of greatly thinned ice together with strong warming albedo feedbacks (see the top post by John Cook, the article by Kay et al (2008) that John Cook links to and which we've both discussed, and my post #12). You're hinting at other things without showing us any evidence for these. For example: (i) in response to my statement: Chris: "However, volcanic activity in general results in transient cooling of the Earth's surface temperature" you say: Quietman: "No. That should be: Volcanic ERUPTIONS in general result in transient cooling from particulates but may be balanced by GHGs from the eruption (or not, depending on the nature of the eruption)." But that makes no sense at all. After all if we look at the entire high resolution atmospheric CO2 record of the last 2000 years [***] we can see that atmospheric CO2 concentrations haven't varied by more than a few ppm around a value of 278 ppm in the period before the mid 19th century. So whereas the particulates from volcanic eruptions might in theory be "balanced by GHG's from the eruption", in practice during at least the last 2000 years, this hasn't been the case. Thus all volcanic eruptions of interest in the topic of this thread have resulted in cooling due to atmospheric aerosols. That's also rather clear from direct analysis of the forcings from volcanic eruptions of the 20th century [*****] [***]Meure CM et al (2006) Law Dome CO2, CH4 and N2O ice core records extended to 2000 years BP Geophys. Res. Lett. 33 L14810 [*****] Hansen et. al. (2005): Earth's energy imbalance: Confirmation and implications. Science, 308, 1431-1435 http://pubs.giss.nasa.gov/docs/2005/2005_Hansen_etal_1.pdf (see Figure 1). The other problem with your assertion about "GHG's from the eruption" is that you've already asserted elsewhere that you don't believe in "CO2-induced AGW" (e.g. in post #9 on this thread). So what are these "GHG's from the eruption" that "balance" "transient cooling from particulates"? Presumably not CO2. After all if the 65 ppm of atmosphere CO2 added to the atmosphere by mankinds emissions hasn't contributed to global warming in your worldview, how can 0.01-0.5 ppm released in a volcanic eruption (that's about the amount released during individual volcanic eruptions of the last around 2000 years) "balance" ""transient cooling from particulates"? Likewise, you suggest that Dr Fairbridge's "hypothesis" allows you to "expect the strong La Nina" "because 2 + 2 usually equals 4". I have no idea what you mean by that. It doesn't seem very scientific at all. However you seem to be insinuating that Fairbridge's "hypothesis" has predictive value for La Nina's (and El Nino's?). Here's a list of the La Nina years in the period 1872 - 2000. I've taken these from Ross Cooper-Johnston's book "El Nino" (Hodder and Stoughton 2000; page xii). Please indicate either: (i) the scientific paper in which Fairbridge demonstrates an analysis that allows this series to be understood in terms of his "hypothesis"... or: (ii) the mathematic equation(s) based on planetary motions/cycles that encapsulates this series... or: (iii) your explanation of the manner in which this series (and the recent la Nina) can be explanied. Here's the La Nina years: 1872-1874 1875-1876 1879-1880 1886-1887 1889-1890 1892-1893 1903-1904 1908-1911 1916-1918 1919 1921 1922-1923 1924-1925 1933-1934 1938-1939 1942-1843 1945-1946 1948-1949 1949-1950 1954-1955-1956 1964 1967-1968 1970-1971 1973-1974 1975-1976 1984-1985 1985-1986 1995-1996 1998-2000 (we could now add early 2006 and late 2007)
131672. Quietman at 06:56 AM on 12 June 2008
        Arctic sea ice melt - natural or man-made?
        chris BTW - Thanks for the 2005_Hansen_et.al. link. A little dated but interesting. Re: "Which "most recent paper"? In what way does it "indicate(s) exactly the opposite of what (I) indicate"?" Please see C. W. Stjern, J. E. Kristjánsson, and A. W. Hansen, 2008a>
131673. John Cross at 06:44 AM on 12 June 2008
        Arctic sea ice melt - natural or man-made?
        Hi John: interesting post (I am familiar with the Canadian side of the Arctic - having spent some time there). I have been following the ice formation here http://igloo.atmos.uiuc.edu/cgi-bin/test/print.sh?fm=06&fd=10&fy=2007&sm=06&sd=10&sy=2008 and to me it looks like we are on for another low year this year. I wish I had taken William up on his offer of a bet!! ;-) JOhn
131674. Quietman at 06:34 AM on 12 June 2008
        Arctic sea ice melt - natural or man-made?
        chris Re: "However, volcanic activity in general results in transient cooling of the Earth's surface temperature" No. That should be: Volcanic ERUPTIONS in general result in transient cooling from particulates but may be balanced by GHGs from the eruption (or not, depending on the nature of the eruption). The term vulcanism, while encompasing eruptions, is much broader. Yellowstone for instance has not erupted but is rising into a dome due to vulcanism, some worry about a supervolcano for which it has the potential. A volcanic eruption signals the start of El Nino but is not the cause of it. The cause of the volcano, however, is the same cause as the El Nino phase of ENSO. My hypothesis is based on what we now know about currents in the magma and the resulting changes in vulcanism from these currents. Also on a hypothesis (not mine) that vulcanism causes the upwelling currents from the SA subduction zone in an El Nino. In addition to magma flow there are tidal effects. These tidal effects are caused by gravitational pull from extra terrestrial bodies and may be amplified by alignments. Dr. Fairbridge explained how these gravitational forces effect the sun, and ssid the strongest effect comes from Jupiter when aligned with other planetary bodies (Mackey 2007). If Jupiter can effect the suns internal currents it can also effect the earths internal currents in my view; and the last full alignment occurred in 1976. The point I am attempting to make here is that you can not put the blame completely on CO2 because it is not alone in atmosphereic warming, let alone polar ice melt and this is borne out by the fact that it is only the north pole so affected. Dr. Fairbridge proposed the hypothesis that the sun is affected by gravitation forces of the solar system and by Jupiter in particular. Dr. Mackey, in his 2007 review of Dr. Fairbridges' work*, predicted the cooling this year and said that this and the next 4 years were the test years for the hypothesis. I (as in my hypothesis) expected the strong La Nina based on the Fairbridge hypothesis because 2+2 usually equals 4. It is the logical result of gravitational forces playing with magma circulation which is signalled by (not caused by, but having the same cause as) low sunspot activity. * Rhodes Fairbridge and the idea that the solar system regulates the Earth’s climate Richard Mackey Canberra ACT 2600 Australia epitrochoid@hotmail.com Journal of Coastal Research SI 50 955 - 968 ICS2007 (Proceedings) Australia ISSN 0749.0208
131675. chris at 05:40 AM on 12 June 2008
        Arctic sea ice melt - natural or man-made?
        Quietman, you really need to put some substance to those assertions. For example in post #9 you mentioned "...ocean warming cycle forcing from increased vulcanism". Now we're talking about the massive retreat of Arctic sea ice in the summer of 2007 on this thread, and the considerable long term trend of diminished Arctic sea ice since the 1960's: http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/seasonal.extent.1900-2007.jpg I agree with you that the period since the 1970's has seen more volcanic activity than, for example, the middle period of the 20th century. However, volcanic activity in general results in transient cooling of the Earth's surface temperature. So obviously volcanic activity in general can't have made any contribution to the massive attenuation of summer Arctic sea ice. e.g. http://pubs.giss.nasa.gov/docs/2005/2005_Hansen_etal_1.pdf (see Figure 1a/c) My post (#12) was written assuming that you meant tectonic activity relating to local magma incursions/ocean crust thinning and so on, since this seems to be the only way that "tectonic activity" might enhance Arctic sea ice attenuation. So what do you mean? What do you mean specifically when you refer to "...ocean warming cycle forcing from increased vulcanism"? Likewise you say that "The most recent paper on Solar Dimming / Brightening indicates exactly the opposite of what you indicate." Which "most recent paper"? In what way does it "indicate(s) exactly the opposite of what (I) indicate"? Likewise you suggest that RW Fairbridge's "hypothesis" "has been the best explanation to date for climate change". Which hypothesis? You indicate that it "so far he has been correct" and that the recent La Nina "was expected". Please give us the citation to the paper in which Fairbridge outlines his hypothesis which allows him to predict the recent La Nina. Or at least explain to us how his analysis predicts the recent La Nina.
131676. Quietman at 02:54 AM on 12 June 2008
        Arctic sea ice melt - natural or man-made?
        chris Good argument. Except for the increased vulcanism. Do not confuse less eruptions for less vulcanism. The earth's been much more active, not less, since 1976. The extreme El Ninos in the ENSO are a direct result. The impact on PDO, Arctic Oscillation and Atlantic Multidecadal Oscillation have not been investigated yet as far as I can tell. The most recent paper on Solar Dimming / Brightening indicates exactly the opposite of what you indicate. But how much impact this may have I am not aware of. There is a link to it near the bottom of "Its the Sun". There is no argument as to whether CO2 is a GHG, only as to AGW as a major factor in the forcing. I agree CO2 is a contributer (as a symptom and a feedback) but disagree on the extent of its participation in warming. AGW is an assumption, an opinion of some scientists but far from all, and that "concensus" is in a slow reduction. Thus far it has not been shown to be the cause and will not be until someone decides at what point the hypothesis can be falsified (stop moving goal posts). Thus far the cycles of the solar system's gravitational forcing has been the best explanation to date for climate change (not just the sun or TSI). In Dr. Mackey's paper (2007) on Dr. Rhodes hypothesis, he says that the test period for the hypothesis is the next 5 years (the paper came out last summer). So far he has been correct (as the ocean cycles are driven by this hypothesis as well, the recent La Nina was expected). In engineering we base our conclusions on facts, not consensus, so my standards for acceptance are somewhat higher. I am content to wait and see if Dr. Mackey and the late Dr. Fairbridge continue to be correct.
131677. chris at 21:50 PM on 11 June 2008
        Arctic sea ice melt - natural or man-made?
        Quietman, in science one follows the evidence and discards hypotheses that don't accord with extant reality. The rapid denuding of the Arctic ice sheet, especially since the 1960's is a result of enhanced surface temperatures. The enhanced surface temperatures have followed the massive enhancement of atmospheric greenhouse gas concentrations, especially since the 1960's. Greenhouse gasses cause the Earth to warm. The best-supported (by the scientific evidence!) estimate for the response to enhanced [CO2] is near 3 oC (=/- a bit) of surface warming per doubling of atmospheric CO2. The Arctic is one of the most sensitive regions of the world to warming since (i) air and ocean currents carry excess heat from the equatorial regions to the high Northern latitudes, and (ii) reduction of albedo from melting sea ice enhances the effects of surface warming. One doesn't need to reiterate all of these well-established (by the evidence!) points every time one writes a paper that discuss the consequences of surface warming. You suggest that the warming might have other origins. However these are not supported by the evidence. You suggest "Water Vapor acting as a GHG in lower latitudes would have the same effect as described, so would solar brightening from lack of aerosols and so would ocean warming cycle forcing from increased vulcanism. " Let's see what the evidence indicates: (i) Water vapour. There can be no persistent increase in water vapour in low latitudes unless the troposphere warms. Persistent changes in water vapour are feedbacks to primary effectors of changes in tropospheric temperature. Water vapour can't just be "added" to the troposphere. It falls right out again. Water vapour partitions in the troposphere according to the tropospheric temperature and pressure. So if its concentrations have changed something priimary must have caused the changes in tropospheric temperature. We know that the troposphere has warmed as a result of enhanced CO2/methane/nitrous oxides. We know that this warming hasn't had a significant contribution from changes in solar outputs at least since the late 1950's. The scientific evidence indicates that tropospheric warming is the result of enhancement of the greenhouse effect, and that this warming has resulted in the expected increase (a well-established feedback) in tropospheric water vapour. (ii) "solar brightening from lack of aerosols". Nope. The atmospheric aerosol load has increased rather significantly since the 1960's. Thus enhanced Arctic sea ice melt has increased despite the overall decreased solar irradiation reaching the surface. Rather than "solar brightening" we've actually had a bit of "solar dimming". e.g. see: Hansen et. al. (2005): Earth's energy imbalance: Confirmation and implications. Science, 308, 1431-1435 (see Figure 1). http://pubs.giss.nasa.gov/docs/2005/2005_Hansen_etal_1.pdf (iii) "...ocean warming cycle forcing from increased vulcanism". Nope. There hasn't been "increased vulcanism" since the 1960's. Let's look at this in more detail, being careful not to be taken in by press release hyperbole: (a) A warm sub-crustal region seems to exist below Northern Greenland [***]. Can this have contributed to enhanced Arctic sea ice since the 1960's? Not really. Consider: (i) the location of the greatly attenunated regions of Arctic sea ice: e.g. comparing sea ice extent in Sept 10th 1979 with that in Sept 10 2007 http://igloo.atmos.uiuc.edu/cgi-bin/test/print.sh?fm=09&fd=10&fy=2007&sm=09&sd=10&sy=1979 The "hot spot" in Northern Greenland is nowhere near the regions of enhanced sea ice melt. [***]van der Veen et al (2007) Subglacial topography and geothermal heat flux: Potential interactions with drainage of the Greenland ice sheet Geophysical Research Letters, VOL. 34, L12501. Braun et al (2007) Gravity-inferred crustal thickness of Greenland; Earth And Planetary Science Letters 262138-158. (ii) That "hot spot" has been there for millions of years (actually it's been there for much longer, but Greenland has "migrated" over the "hot spot" millions of years ago). Is it likely that just at the time (since the 1960's) we've been enhancing the Earth's surface temperature by pumbing out greenhouse gasses, the "hot spot" has suddenly become "hotter"? Nope. (iii) Do sub-crustal magma chambers ("hot spots") and even surface volcanos produce persistent increases in surface temperatures? Not really. Consider the most active magma chambers and volcanic activity in the high Northern latitudes. They sit right under Iceland which sits astride the opening of the North Atlantic where two tectonic plates pull apart. By your hypothesis that must have produced rather large surface warming in recent times? In fact the opposite is true. If one inspects the pattern of surface warming during the period of massive man-made enhancement of the Earth's greenhouse effect, the region around Iceland is one of the few places which has undergone a mild cooling: e.g., consider Arctic surface warming 1954-2003 http://arctic.atmos.uiuc.edu/CLIMATESUMMARY/2003/IMAGES/annual.1954-2003.tchange.png (iv) In fact we know that even volcanos that breach the polar ice cap surfaces don't make much of a contribution to widespread contemporary ice sheet or sea ice melting [*****]. For example a "recent" (around 250 years BC) volcanic eruption has been identified in the West Antarctic ice sheet, and there is a bit of a "hot spot" there too. However as the authors point out this can't be impacting the widsespread thinning of glacial ice in the region: "Therefore, even if continuous or episodic production of melt water from HMSV affects Pine Island Glacier, there is little likelihood that it could affect these neighbouring glaciers. It is thus possible that volcanic activity over HMSV contributed to some of the recent changes in velocity of Pine Island Glacier27, but it cannot explain the widespread thinning that has been observed across these glacier basins in recent decades. We follow previous authors30 in favouring an oceanic driver as the likely cause for these changes." [*****]Corr & Vaughan (2008) A recent volcanic eruption beneath the West Antarctic ice sheetNature Geoscience 1, 122 - 125 (2008) ....and so on....overall you seem to be rejecting rather straightforward conclusions based on a wealth of well-established scientific data, and plumping for explanations for which the evidence is actively contrary.
131678. John Cross at 20:20 PM on 11 June 2008
        Arctic sea ice melt - natural or man-made?
        Hi John: interesting post (I am familiar with the Canadian side of the Arctic - having spent some time there). I have been following the ice formation here http://igloo.atmos.uiuc.edu/cgi-bin/test/print.sh?fm=06&fd=10&fy=2007&sm=06&sd=10&sy=2008 and to me it looks like we are on for another low year this year. I wish I had taken William up on his offer of a bet!! ;-) JOhn
131679. Quietman at 16:37 PM on 11 June 2008
        It's Urban Heat Island effect
        John I know this may sound strange but the Urban Heat Island Rffect is so far the only proof we have that there is AGW. The urban enviroment produces additional heat, moreso in some cities like New York because the public buildings are heated by steam piped in from a central location. To maintain boiler pressure it is bled off to the atmosphere daily. In addition the pipes are old, poorly insulated and leak. You dont get ice on the road in NYC. Add to that the fact that the heated surfaces take longer to cool and to have a positive man made input. Industy, especially steel and power plants produce extra year round heat. Every home and vehicle produce heat and in the case of vehicles its direct from the radiator and more since the clean air act because to decrease emissions the engine must run at least 10 degrees F hotter than a normal winter thermostat. We used to use 160 F for warm climates and 180 F for cool climates, now we use 190 F for both. So we do in fact have good evidence for AGW that does not involve GHGs at all. I do not believe the IPCC models account for this and I know they correct for stations in urban environments. What they should be doing is using two uncorrected data sets, One from rural stations only to see what the temperature actually is and another for urban environments to see how much is being added. Well I said it may sound strange.
        Response: There is no doubt temperatures are greater in urban areas than surrounding rural areas. The important question is does this mean the warming trend is greater? Jones 2008 looks at this and finds even though urban areas are warmer, the trend is the same. Another important question is whether developing urban areas have an impact when averaged out over large areas. Again Jones 2008 finds no impact.
131680. Lee Grable at 16:35 PM on 11 June 2008
        The Mystery of the Vanishing Ocean Heat
        Concidering how much heat the oceans released to the atmosphere during the 97-98 El Nino, could this be a delayed effect from that?
131681. Quietman at 16:12 PM on 11 June 2008
        Arctic sea ice melt - natural or man-made?
        I seem to have dropped the r.
131682. Quietman at 16:10 PM on 11 June 2008
        Arctic sea ice melt - natural or man-made?
        chris I am sorry but to say the cause is involving CO2 to any serious degree is assuming that the hypothesis for current CO2 induced AGW is correct. All of the above papers make that assumption without any attempt to prove that assumption correct. Water Vapor acting as a GHG in lower latitudes would have the same effect as described, so would solar brightening from lack of aerosols and so would ocean warming cycle forcing from increased vulcanism. To be accurate, you can say for a fact that the ice thinned from some form of heating, possibly GHG, possibly CO2 but you can not assume that it is anything specific without proof. Thus far there is absolutely no proof of any serious effect from AGW - the cause is still hypothetical. Working from other peoples assumptions is just bad science. Kay et. al. in fact do not mention CO2 at all in the 2008 pape
131683. chris at 05:24 AM on 11 June 2008
        Arctic sea ice melt - natural or man-made?
        You haven't got that quite right I think, Quietman. The extent of summer sea ice melt over the Arctic in 2007 certainly wasn't natural. It was a combination of a natural phenomenon intercepting with strongly "unnatural" conditions. If you read Kay et al (2008), it's clear that the authors indicate that their analysis is consistent with a natural, but not uncommon, phenomenon (decreased cloudiness and increased longwave downwelling) being greatly augmented by the fact of a greatly attenuated Arctic ice sheet (both in extent and thickness) that has been occurring since the 1960's, as a result of increased global surface temperatures (global warming) which have predominated over the Northern polar regions. e.g. see historical sea ice extent data at the Uni of Illinois Arctic Climate Research Center: http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/seasonal.extent.1900-2007.jpg It's the already attenuated loss of polar ice and ice thickness that lead to a (not-unprecedented) phenomenon having such a large effect. Two points are pertinent [see Kay et al (2008)]: (i) The increased LW downwelling is calculated by Kay et al to yield increased surface thermal energy sufficient to melt an extra 0.3 m of ice (or 0.7 m of ice in broken seas where albedo feedbacks kick in). In previous years [see point (ii)], when the sea ice was considerable thicker, 0.3 metres of melt wasn't sufficient to clear large areas of ice and so the sea-ice extent was (a) not diminished much, and (b) consequently, reinforcing albedo effects didn't arise. (ii) This is clear from the observation that the 2007 cloud/LW downwelling phenomenon was by no means unprecedented. Thus [see Kay et al (2008)], the Barrow measurements of cloud cover show that the years 1968, 1971, 1976, 1977 and 1991, for example, all had even lower cloud cover than that of 2007. However (see the link to the Uni. Of Illinois sea ice extent data just above in this post), there was no significant deviation from the trend of sequentially reduced summer sea ice extent during these years. In other words the weather conditions pertaining during the summer of 2007 shouldn’t have resulted in the massive attenuation of sea ice. Unfortunately, the “baseline” situation in the Arctic has changed. As Kay et al (2008) conclude: In a warming world "cloud and shortwave radiation will play an increasingly important role in modulating summertime sea ice extent." The other papers are generally in line with these rather straightforward conclusions. We've always known that the Arctic would be one of the most sensitive areas for observing consequences of global warming, since it is a "focus" for strong heat transfer from the equator, and it's an area where strong positive feedbacks due to loss of albedo from warming-induced sea ice melt will be observed in a warming world. That's pretty much exactly what Kay et al are highlighting. This statement in your post #4 is also a bit dodgy: "But this is not what Francis or SHimada said in 2006 (at least according to the abstracts), they clearly state "air temperature, water vapor and cloudiness" and "ocean heat", with no mention of CO2, but instead the more powerful GHG: water vapor." But it's obvious that: (i) "air temperature" refers to warmer air temperatures (the air temperature is rising due to enhanced greenhouse effect) (ii) "water vapour" refers to increased water vapour concentration that occurs spontaneously in warmer air. Remember that water vapour concentrations are effectively "set" by the air temperature (and pressure) and doesn't vary independently of primary warming (or cooling) influences. In other words water vapour concentrations can't just rise on their own! They're always feedbacks. (iii) "ocean heat" refers to the increased heat in the ocean due to global warming (and albedo effects as summer sea ice is increasingly denuded)…and so on…. i.e., the fact that a paper doesn't mention CO2 doesn't mean that effects from increasing greenhouse gases aren't implicitly or explicitly meant! After all man-made greenhouse gases included CO2 and methane and nitrous oxides directly and water vapour indirectly. However one doesn't have to keep spelling it out in every paper that's written.
131684. Quietman at 04:56 AM on 11 June 2008
        The Mystery of the Vanishing Ocean Heat
        Sorry - I put them in the wrong order.
131685. Quietman at 04:55 AM on 11 June 2008
        The Mystery of the Vanishing Ocean Heat
        John Heres an update on ocean cooling (top link) and background (bottom link) - Interesting I think. The Southern Hemisphere westerly winds have moved southward in the last 30 years. A new climate model predicts that as the winds shift south, they can do a better job of transferring heat and carbon dioxide from the surface waters surrounding Antarctica into the deeper, colder waters. The new finding surprised the scientists, said lead researcher Joellen L. Russell. "We think it will slow global warming. It won't reverse or stop it, but it will slow the rate of increase." Southern Ocean Could Slow Global Warming - ScienceDaily (Dec. 5, 2006) The current consists of a number of fronts. Observations indicate that turbulent mixing is enhanced in these fronts, penetrating through much of the water column. Noting that understanding the ACC is important to understanding regional and global ocean circulation, Saenko feeds a simple representation of mixing along the current's fronts into a global climate model to evaluate the mixing's potential impact on ocean's overturning circulation. Antarctic Current Roils Deep Ocean Waters - ScienceDaily (Jun. 6, 2008)
131686. TruthSeeker at 03:17 AM on 11 June 2008
        It's the sun
        The following comments are challenges to the theory of global warming that I haven’t heard any successful retort: • Post by Barry on Jan 30th – “I question the physics behind the response: a crucial finding was the correlation between solar activity and temperature ended around 1975......The assumption is that there is always an energy balance between heat radiated from earth and input from the sun. Lets say that solar activity remained above this energy balance, one would have to assume that temperature would still increase, until some new energy balance is achieved. This means that temperature can still increase as long as the input is greater that the output. • Post by tbandrow on March 7th – “Well, solar flux doesn't need to be argued. It can be proved. The current solar theory is due to an interaction that has something to do with sunspots. So, if that is the case, then we can see if the global temperature will go down, assuming the present dearth of sunspot continues.” Yes I saw the comment regarding La Nina, but his point was as we have more time years with low sun spots and cooling temperatures we can rule out irregularities like La Nina, can’t we? • Post By Dan Pangburn on April 14th – “From the Vostok ice core data, during glacial periods, often a rising temperature trend with a rising carbon dioxide level suddenly changed direction and became a falling temperature trend in spite of the carbon dioxide level being higher than when the temperature was increasing. This could not be if carbon dioxide causes a positive feedback. The Andean-Saharan Ice Age occurred when the carbon dioxide level was over ten times its current level. What is different now that could lead to run away temperature increase?” I find this argument to have particular merit, since by the accounts and data that I have seen, we haven’t seen any statistical temperature increase in the last 10 years (per NOAA data), yet we continue to increase CO2 concentration. If someone would point me to the arguments that have been made (or make new ones) that offer explanations or counterpoints, I would greatly appreciate that.
131687. Quietman at 01:51 AM on 11 June 2008
        Arctic sea ice melt - natural or man-made?
        John No, your argument was clear and well written, my confusion is in the supporting papers and the asumption made that the thinning was caused by AGW (Gascard 2008). I think the cause is much more dynamic than just GHGs from other papers I have read. The explanation for the sudden melt is quite understandable.
131688. Quietman at 13:47 PM on 10 June 2008
        It's the sun
        Second order skeptic John has a whole page devoted to Sloan 2008 titled Do Cosmic Rays Cause Clouds that you might want to look at. The lower link to "Global dimming and global brightening - an analysis of surface radiation and cloud cover data in northern Europe" I found very interesting.
131689. Quietman at 13:31 PM on 10 June 2008
        Arctic sea ice melt - natural or man-made?
        From the opening line in the Abstract (Gascard 2008): "The Arctic is undergoing significant environmental changes due to climate warming." I assume that this must be a different "anticyclonic pattern" than the one spoken of in Kay 2008 since it has a different cause. Or is that why you titled this in the form of a question?
131690. Quietman at 13:05 PM on 10 June 2008
        Arctic sea ice melt - natural or man-made?
        John I know that Kay 2008 was not about CO2, but it was the only paper I could read and try to relate to the question posed in the title "natural or man-made?". It is obvious to me that summer 2007 was natural over the arctic from that paper so I had some difficulty figuring it out in context. After reading Nghiem 2007, Comiso 2003 and Rigor 2000, I started to put it into context to see how you intend it to support AGW. No offense but I am not convinced.
        Response: I thought I'd spelled it out but hopefully this'll make it clearer. The dramatic sea ice melt in 2007 was largely due to natural weather conditions - the strong winds moving ice out of the Arctic and reduced cloudiness. Kay 2008 looks at the natural weather conditions causing the reduced cloudiness.
        
        So the answer to the question "is Arctic ice melt natural or manmade?" is both. The long term trend is manmade but natural weather conditions in 2007 added to the trend, with dramatic effect. Plus the long term trend weakened the sea ice so that it was more vulnerable in 2007.
131691. Quietman at 12:52 PM on 10 June 2008
        Arctic sea ice melt - natural or man-made?
        John Re: "Downward longwave radiation has increased, as expected when air temperature, water vapor and cloudiness increases (Francis 2006). More ocean heat is being transported into Arctic waters (Shimada 2006)." In Comiso 2003 - what the "Arctic is expected" to do is based on Budyko, M. I., 1966: "Polar ice and climate", as well as "atmosphere model to gradual changes of atmospheric CO2. Part II: Seasonal response", by Manabe, 1992. Cosimo 2003 is in turn referenced by Nghiem, 2007 for support. The CO2 hypothesis appears to be accepted defacto from 1999 as the cause: Using simulations by global climate models (RIGOR 1999) "These changes in surface air temperature over the Arctic Ocean are related to the Arctic Oscillation, which accounts for more than half of the surface air temperature trends over Alaska, Eurasia, and the eastern Arctic Ocean but less than half in the western Arctic Ocean." Also on Dec. 16, 1999, there was a press release "Evidence mounts for Arctic Oscillation's impact on northern climate" which said this could be part of human-induced climate change. But this is not what Francis or SHimada said in 2006 (at least according to the abstracts), they clearly state "air temperature, water vapor and cloudiness" and "ocean heat", with no mention of CO2, but instead the more powerful GHG: water vapor. To attempt to decipher all this I found a site that explained that the main constant is that the climate in all arctic areas is affected by the extreme solar radiation conditions of high latitudes. This site also contains the basics and terminology used so that the layman can more readily understand. Kay 2008 aside, I did not see mention anywhere of the other contributers to the ice melt that I have read about since last fall but the 3 I read assumed AGW caused the thinning and were published prior to the discovery of vulcanism's contrinution under and around Greenland. So I am still skeptical.
131692. Quietman at 04:20 AM on 10 June 2008
        Arctic sea ice melt - natural or man-made?
        I tried again and was able to download Nghiem 2007, Comiso 2003 and Rigor 2000 this time around (I already had Kay 2008). I overlooked one of these earlier but the other two apparently had server problems. But for Francis 2006, Shimada 2006, Perovich 2007, Stroeve 2007, Stroeve 2008 and Gascard 2008, I still get only abstracts and a form to purchase the paper. I'll get back later after reading the 3 additional PDFs. Thanks.
        Response: Any time I could find an online PDF, I'd link to that. In the cases where only the abstract was available, I'd email the author and 9 times out of 10 they'd email me the full paper. I'll be happy to email you any of the papers if you're interested.
131693. Philippe Chantreau at 02:07 AM on 10 June 2008
        Arctic sea ice melt - natural or man-made?
        I didn't have problem with any of the links and only the Gascard paper was limited to the abstract.
131694. Second order skeptic at 01:53 AM on 10 June 2008
        It's the sun
        Two more studies to add to your impressive list of twelve: Sloan et al. 2008, http://www.iop.org/EJ/abstract/1748-9326/3/2/024001 Kristjansson 2008, http://folk.uio.no/jegill/publications.html (first link)
131695. Quietman at 00:56 AM on 10 June 2008
        Arctic sea ice melt - natural or man-made?
        John Unfortunately two of the links would not open for me* and all but Kay 2008 were only abstracts. As Kay et. al. does not mention carbon dioxide anywhere in the body of the paper and neither did the abstracts, there is no indication that it was caused by AGW. The paper and abstracts all refer to heat transfer from ocean currents but really do not answer your question one way or another. Very interesting reading however. * no error messages just blank pages - probably server problems rather than bad links.
        Response: Kay 2008 isn't about CO2 but about the weather conditions in 2007 that caused reduced cloudiness throughout the 2007 summer.
131696. Quietman at 07:14 AM on 9 June 2008
        Misinterpreting a retraction of rising sea level predictions
        nealjking That is not how science works. GW is a hypothesis, albiet a fair one. The problem is that it has been accepted as a working hypothesis but has not been proven. Climate change, on the other hand, is obvious. Most of the natural forcing are proven, albeit not all. Science works by proving your hypothesis valid, which may or may not prove an alternate hypothesis invalid (two different functions can have similar results). Yes I have a higher standard of evidence to meet, but I do not deny GW, rather I am very skeptical of CO2 as the cause of GW or that AGW is actually an important factor in climate change. There have been very good peer reviewed papers indicating natural causes that fit the picture much better than CO2 induced AGW. The jury is still out on this. I am not posting links here because they do not relate directly to this issue (Did global warming stop in 1998?) but if you read through the rest of this site you will find plenty of links to some very interesting papers (both from John and in the comments). But "framework theory, it has to be DISPROVEN to be invalidated." is a false premise as it too is a hypothesis, albeit a good one.
131697. Quietman at 06:02 AM on 9 June 2008
        Global warming stopped in 1998, 1995, 2002, 2007, 2010, ????
        Will Nitschke As a skeptic I find this site the most open minded of all the climate blogs I have visited, especially when compared to our American sites. I find the links and graphs especially useful and highly recommend this site to others who often comment on the web.
131698. Quietman at 05:52 AM on 9 June 2008
        April update on global cooling 2008
        Actually today will set a record high if the predicted temp is reached. (all temps in F)
131699. Quietman at 05:48 AM on 9 June 2008
        April update on global cooling 2008
        Local update - switch from below average to above average: Mo.,. u Lo, u Hi, u Precip, Record Lo, Record Hi Jun 1, 49°, 72°, 0.14 in, 31° (2001), 88° (1937) Jun 2, 49°, 72°, 0.14 in, 34° (1998), 85° (1989) Jun 3, 49°, 72°, 0.14 in, 32° (1929), 86° (1978) Jun 4, 49°, 72°, 0.14 in, 30° (1926), 86° (1990) Jun 5, 50°, 73°, 0.14 in, 34° (1964), 88° (1943) Jun 6, 50°, 73°, 0.14 in, 33° (1929), 86° (1973) Today, 66°, 88° this switch from cooler to warmer occurred a couple days ago, and the forcast for the next few days is like today. Above average but not record setting. Again the record years are of interest.
131700. Quietman at 08:11 AM on 8 June 2008
        A new twist on mid-century cooling
        Steve L Re: "Were temperatures read to the nearest degree?" As I am only 60 I really can't say. People who served in WW2 would have to be at least 80 but most would be in their 90s now. Any old-timers out there?

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