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Comments 130651 to 130700:

130651. Quietman at 05:36 AM on 17 November 2008
        It's Pacific Decadal Oscillation
        Roy Spencer's view on how the PDO fits the equation:, a brief part of a new paper being submitted.
130652. chris at 12:37 PM on 16 November 2008
        It's the sun
        Re #212, On Spencer and "political beliefs"... Well yes, Mizimi, I suspect that your apparent missunderstanding of the nature of science in relation to religion and politics is a contrived one (played out for comedy effect?....or maybe you just like reading my posts!). I'm sure you know really that science is all about the evidence, and that's the essential difference between science and religion or political advocacy. So one would only pursue the deceit that CO2 all of a sudden has stopped being a greenhouse gas (or that the massively raised levels of atmospheric CO2 were from volcanoes), for example, if one was attempting to make some sort of political (or other agenda-led) capital. Wouldn't you say so? The similarities between global warming denialism and modern-style "creationism" are interesting, and Spencer provides an example of how these can induce a perversion of scientific evidence in support of an agenda. In the US these stances have a tendency to coincide, such that it's quite common for those that wilfully choose to ignore or misrepresent the scientific evidence for evolution (e.g. "hard core" neo-"Christian" chaps!) are also likely to participate in misrepresenting the science on global warming. I find it particularly fascinating that someone who's career as a staff scientist involved "measuring" tropospheric temperatures would drift down this route, but there seems to be a particularly attractive (for some people) political position in the US that induces this anti-rational behaviour...and which incidentally is catnip for those with really serious anti-science efforts to pursue (e.g. pretending that smoking isn't a strong contributory factor in lung cancer and respiratory and circulatory disease..or that aspirin taking in children doesn't enhance their likelihood of contracting Reyes syndrome...that sort of thing!).
130653. chris at 12:26 PM on 16 November 2008
        Evaporating the water vapor argument
        Very funny Mizimi I particularly liked the "White staffer" Lew Moninsky! (The Greenpeace "spkesperson Rainbow Treetower is a bit obvious...)
130654. chris at 11:29 AM on 16 November 2008
        It's the sun
        Question 1: Very little CO2 has been added to seawater by "undersea" volcanic activity. We know this from (at last) two sources. (i) If undersea volcanic activity resulted in significant acumulation of CO2 in the oceans, then we should see (have seen) some of this released into the atmosphere. However we have atmospheric CO2 records going back millions of years. One would have to make the rather specious "argument" that undersea volcanic activity has all of a sudden, after millions of years, started releasing large amounts of CO2 just when mankind has stared releasing vast amounts of CO2. However there's no real world evidence for enhanced undersea volcanic activity, let alone enhanced production of CO2 from volcanic activity. And we know anyway [see posts #201/208 and (ii) just below] that the massive amounts of CO2 in the atmosphere that is partitioning in massive amounts into the oceans is from fossil fuels. (ii) As already described, tectonic activity in general results in release of very small amounts of CO2 {less than 1% of current anthropogenic levels) and this is largely from non-organic sources. Undersea volcanic activity is by definition undersea (!), and the sources of undersea volcanic activity are at sites of nascent plate boundaries (e.g. Mid Atlantic ridge) or mantle plumes (e.g. under Hawaii). Any CO2 released from these sources have pretty normal 13C/12C compositions (around 1% 13C) since the carbon is almost exclusively from non-organic sources. In fact it may be more likely that CO2 from land volcanoes (at subduction zones on continental margins) will have a little CO2 from organic sources since these will release some CO2 from carbon previously subducted from the ocean floor, a bit of which might be organic ('though not much, since organic material in the ocean finds itself utilised within the food chain...). But in general volcanos (either undersea or on land) release rather small amounts of CO2, and the carbon isn't particularly 13C-depeleted. and so on...there more evidence from proxy measures of sea-water pH and such like... Question 2: The amount of 13C from nuclear tests/accidents is tiny in proportion to the amount of natural 13C in the environment. 13C comprises around 1% of carbon (it's naturally abundant at around 1%). The contribution from non-natural sources is immeasurably small. The situation is a bit different for 14C. Remember that 13C is a stable isotope of carbon whereas 14C is an unstable radioactive isotope, which additionally has a very short half-life (6000-ish years). The fact that there is any appreciable amount of 14C in the environment at all, is that this is being continually produced in tiny, tiny amounts by the action of gamma rays in the upper atmosphere. So the contribution from mid-20th century nuclear testing is significant, and there is a bit of a "spike" in the atmospheric 14C record...
130655. chris at 11:27 AM on 16 November 2008
        Water vapor is the most powerful greenhouse gas
        Source please Mizimi for those columns of faux-"numerology". Where did you cut and paste them from and what do the columns mean?
130656. Mizimi at 09:18 AM on 16 November 2008
        It's Urban Heat Island effect
        PS: another thermal image site for Paris, France: http://www.geo.uni.lodz.pl/~icuc5/text/O_27A_2.pdf
130657. Mizimi at 09:11 AM on 16 November 2008
        It's Urban Heat Island effect
        Have alook at http://www.seedgen.com/thermallondon/space.htm#space "LONDON FROM SPACE Adapted from material kindly submitted by the The British National Space Centre on behalf of the Science and Technology Facilities Council London and many other English cities can be seen as bright thermal `footprints' in this night-time image of England, France and the English Channel. In the false-colour representation used here, temperature increases through blue and yellow to orange over a temperature range of 278-288K (= 5 to 15 degrees Celcius). London Airport reservoirs appear as orange hot spots as they remain hotter than the surrounding land that has cooled quicker since the sun has gone down; the water bodies have a higher thermal inertia than the land due to the higher specific heat capacity. The image was from captured by the European Space Agency's (ESA) ERS-1 satellite at an altitude of around 777 km. (This is a 12 micron night-time image acquired on 7th September 1991; the area covered is 512 x 512 square km.)" Note the temperature range...10C Also , on the same web site you can see THERMAL images of the UK which clearly show the higher temps around cities.
130658. Mizimi at 09:00 AM on 16 November 2008
        It's the sun
        Question: My understanding is that most 'volcanic' activity is undersea and that the CO2 thus produced would go more or less immediately into solution? In which case how can one quantify how much is being added...? Question: How much C13 has been produced by nuclear tests and accidents? And what effect has it had on the general level of C13 in atmospheric CO2 ? "Unfortunately Spencers "style" of ceationism ..... is really a political position." Well, given the minimilistic numbers on A CO2 contribution to 'global warming' one could well say the same of adherents to that belief.
130659. Mizimi at 08:10 AM on 16 November 2008
        Water vapor is the most powerful greenhouse gas
        some sums.............contribution to greenhouse effect: 'natural' 'man added' WV 94.999% 0.001% CO2 3.502% 0.117% CH4 0.294% 0.066% NO2 0.903% 0.047% rest 0.025% 0.047% So A.CO2 contributes around 0.117% of total greenhouse effect.....33 x 0.117% = .038 degC Total A GG's contribute around 0.28%...33 x 0.28% = 0.09 degC
130660. Mizimi at 07:49 AM on 16 November 2008
        It's cosmic rays
        It is suggested that high level cloud formation is not affected because of the differences between ice crystals (high level)and vapour ( low level). There is a strong correlation between CR's and low level cloud referred to in this paper... http://www.solarstorms.org/CloudCover.html cosmic ray/low cloud cover. "The correlation of low cloud factor and cosmic ray flux is unexpected as the maximum degree of ionization by cosmic rays occurs in the altitude range 12-15km, i.e. close to or above the tropopause. The altitude ranges covered by clouds of different type are: 0-3.2 km for the low clouds, 3.2-6.5 km for the mid-level clouds and 6.5-16 km for the high clouds. Thus any cosmic ray induced cloud effect would be expected to be stronger for high rather than low cloud layers (Kernthaler et al. 1999; Jorgensen and Hansen, 2000). An explanation may lie in the fact that, as the neutron detectors are located at ground level, the measured flux is more representative of lower than higher regions of the atmosphere. Also, we suspect that the physical state of the cloud droplets may play a significant role in the cosmic ray-cloud interaction. It has been pointed out before that the physics of ice and liquid clouds may differ (Gierens and Ponater, 1999). By analysing different low cloud types separately we found that clouds in a liquid phase account for almost all the variability during the observed period, leaving the ice clouds constant in time, except at the poles where a slight increasing trend for some of the ice cloud types is found. Thus the greater sensitivity of low cloud to cosmic rays may result from the preponderance of liquid phase cloud types at lower altitudes (less than 6-7 km). "
130661. Mizimi at 07:40 AM on 16 November 2008
        Evaporating the water vapor argument
        "(Washington, DC) The Environmental Protection Agency is seeking to classify water vapor as a pollutant, due to its central role in global warming. Because water vapor is the dominant greenhouse gas in the atmosphere, accounting for at least 90% of the Earth's natural greenhouse effect, its emission during many human activities, such as the burning of fuels, is coming under increasing scrutiny by federal regulators. Until now, the carbon dioxide produced during the burning of fuels has been the main concern. The extra carbon dioxide causes a manmade enhancement of the greenhouse effect. But water vapor is also produced by combustion of most fuels, as well as by industry and utilities that use water for cooling. The EPA would be able to regulate its manmade sources if it is classified as a pollutant. EPA Director of the Department of Pollutant Decrees, Ray Donaldson, said, "Back before carbon dioxide was dangerous, we simply assumed that water vapor was also benign. But all reputable scientists now agree that the increased water vapor content of the atmosphere from such sources as burning of fuels and power plant cooling towers will also enhance the greenhouse effect, leading to potentially catastrophic warming." http://www.ecoenquirer.com/EPA-water-vapor.htm see post #16
130662. Philippe Chantreau at 13:37 PM on 15 November 2008
        Arctic sea ice melt - natural or man-made?
        Beck is no "professor." What are his publications? (Energy and Environment does not count)
130663. chris at 11:18 AM on 15 November 2008
        Models are unreliable
        Oh dear. You're attempting to sell the unsubstantiated deceit that climate scientists don't understand feedbacks in relation to the earth's energy budget, and thus you can make a blanket dismissal of everything I present or every reference I cite. That's an excellent wheeze..you're entranced by the conceit that you are right and everyone else is wrong! Sadly, so far it's been easy to show that it is you that has glaring misconceptions on the science. Let's look at the essential errors in your post #67: 1. I pointed out that the UAH satellite data is rather dodgy, bedevilled as it is by a slew of errors yielding artefactual cooling trends (see references cited in post #66). The RSS data set is likely to be rather more accurate. Not very controversial I think. 2. I also pointed out that the tropospheric temperature measures are not particularly robust (they are broadly consistent with the land-sea surface record, but are not particularly well-constrained), and that while efforts are made to improve these, particularly in relation to calibrations, and taking account the relatively short time series (satellite measurements of tropospheric temperatures are available only from 1979), it makes more sense to consider the land-sea surface temperature measures if one wants to establish how our world is responding to enhanced greenhouse gas forcing (see references cited in post #66). Not very controversial either. 3. These (NASA GISS, Hadcrut, NOAA) show long warming trends from the mid 1970's through to the present. 4. You are choosing to make an analysis in which part of the land-sea surface 2008 data (the first 9 months) is compared to the 2000-2007 mean. But it doesn't make any sense in the context of greenhouse-forced warming trends, to compare single years (or parts of year) with anything. This should be obvious. Here’s why: 5. The land-sea surface records show a warming trend somewhere near 0.18-0.2 oC per decade over the last 30-ish years. Obviously, since year on year variations can result in short term drops or rises in the surface temperature by 0.1 oC (or even 0.2 oC if one considers the effects of the extraordinary El Nino year, 1998), one needs to consider trends over longish periods - looking at parts of single years is highly misleading, since there is rather a lot of “noise” on the temperature record. 6. Let's look for example at your cherrypicked early-mid 2008. The first 5-6 months of 2008 were strongly influenced by a La Nina episode that suppressed the surface temperature measurably. In addition the sun has reached the very bottom in its 11 year solar cycle and will only start to significantly supplement greenhouse warming in a couple of years. So we've had a short period when "cooling" phenomena have coincided. That's measured in the surface (and tropospheric) temperature records. Not a big surprise. 7. But of course if we're interested in how the Earth's surface temperature responds to enhanced greenhouse warming, we don't play at contrived wonderment that the surface temperature has cooled a bit due to fluctuations that happen to be in a cooling direction for several months. In another years or two the rise in the solar cycle will be supplementing the greenhouse enhanced forcing rather than opposing it as in the last few years. No doubt we’ll get the next record year at the next significant El Nino or two… Here's the other problems in your post: 1. Oddly, while you attempt to make an "argument" on the basis of a short 9 month period, you then proceed to attempt a completely contrary “argument” around the notion; [Dan Pangbourn: "But understanding global climate does not come from examining a period so brief as the last decade, or even the last century"]. A lovely cherrypicking of 9 months of data is fine though! The other problem with the "argument" that you attempt to develop from that, is that no-one has ignored the temperature changes during the past 1000 years. There's a reasonably good understanding of those (hint - it's the sun and volcanic activity that has resulted in small and slow changes in the earth's surface temperature during those periods). Note that the Earth's surface temperature "recovered" from the Little Ice Age by around the middle of the 19th century. I wonder whether you are trying to pretend that 20th century and contemporary warming is "recovery" from the LIA! 2. Be aware that the only predictors of significant Anthropogenic Global Warming are certainly NOT Global Climate Models or GCMs. What an odd notion to try to insinuate; what evidence lends to you consider such an ill-informed idea? The major predictor of Anthropogenic Global Warming is our understanding of the Earth's greenhouse effect and the physics/thermodynamics of the response of the earth's energy budget to enhanced greenhouse forcing. That's why (to give one of dozens of examples going pack to the mid 19th century), Wallace Broecker was able to predict in 1975 that the Earth’s global temperature would likely be warmer by the early 2000’s than at any period in the previous 1000 years. The evidence indicates he was right. [[b][/i]Broecker, WS (1975) “Climate Change: Are we on the brink of a pronounced global warming ? Science 189, 460-463[/i][/b]] Broecker didn’t have a GCM at hand (and nether did John Tyndall in the mid 19th century nor Arrhenius in the late 19th century and so on, each of whom understood that atmospheric CO2 contributed to the Earth’s enhanced temperature above its “black body” temperature and the effects of enhancing greenhouse gas forcings). You seem to have a severe misconception of the scope of GCM’s and their use in relation to understanding the evolution of the climate in a warming world, its spatial distribution and consequent effects (rainfall patterns, heat transfer by air and ocean currents and so on). So let’s not pretend that anthropogenic global warming arises magically from climate models. We’ve known about global warming in response to anthropogenic enhancement of the earth’s greenhouse effect for over 100 years. 3. There isn’t any data from the Vostok core that indicates “its been warmer than now at other times during the Holocene”. Unless by “it” you mean Vostok. One location does not a global temperature make. 4. It does seem to have been a tad warmer during the last interglacial period particularly around 130,000 to 125,000-ish years ago. Unfortunately sea levels were around 4 metres higher then than now as a result. That’s one of the many reasons we don’t want to push temperatures up much further. 5. What “quiet sun”? The present minimum which is opposing enhanced greenhouse-induced warming will in a year or two begin to “supplement” this. Getting excited about the low point in the rather regular 11 year sinusoidal variation in the solar output is nonsense. And your repeated misconception about feedbacks: 6. Despite agreeing that enhanced CO2 results in enhanced greenhouse forcing with resultant atmospheric warming that yields a water vapour feedback, and the abundant evidence that the Earth responds to enhanced atmospheric CO2 concentrations with a warming encompassing a net positive feedback that yields a surface temperature near 3 oC, you still assert with zero substantiation that net positive feedbacks don’t exist. I wonder when you’re going to provide any evidence in support of that assertion other than “I know I’m right and everyone else is wong”! I explained some of the essential features of feedbacks in post #64. Your response was to parrot your mantra (paraphrasing) “I’m right and everyone else is wrong”. Some argument!.....
130664. Dan Pangburn at 07:30 AM on 15 November 2008
        Models are unreliable
        The discovery that the Climate Science Community is uninformed on Dynamic System Theory and the ramifications thereof were presented at post 61. Their lack of understanding of Dynamic System Theory prevents them from recognizing that some important aspects of earth’s climate are easily determined; specifically that the imposition of significant net positive feedback in their GCMs is a mistake (other deficiencies regarding GCM use are listed at post 32). All of Chris’ comments and references should be considered in the context that they are uninformed in a relevant part of science and that they are unaware that they are uninformed. Chris presented an extensive diatribe (including several references) denigrating the UAH reporting of lower atmospheric temperature anomalies that were based on measurements made by satellite. The diatribe includes comments such as “incompetent disregard”, “UAH is a dodgy source” and “scandalous record”. Then Chris writes “The RSS tropospheric data is likely to be more robust.” The reader is invited to look at the RSS data set. It can be seen at http://www.ncdc.noaa.gov/oa/climate/research/rss_monthly_msu_amsu_channel_tlt_anomalies_land_and_ocean.txt . Doing the same analysis on the RSS data as was done on the UAH data shows that the AVERAGE GLOBAL TEMPERATURE for the first 9 months of 2008 is LOWER than the average from 2000 thru 2007 by an amount equal to 39.8% of the total linearized increase (NOAA temperature anomaly data) during the 20th century. Thus the RSS data corroborate the UAH data. It will be interesting to see what fault Chris now finds with the RSS data. Both the UAH and RSS data sets use satellite information which measures lower atmospheric temperature. The atmosphere has low thermal capacitance (ability to store heat) so it changes temperature comparatively quickly. The other sources: Hadley, http://www.cru.uea.ac.uk/cru/data/temperature/hadcrut3gl.txt, GISS, http://data.giss.nasa.gov/gistemp/tabledata/GLB.Ts+dSST.txt and NOAA, ftp://ftp.ncdc.noaa.gov/pub/data/anomalies/monthly.land_and_ocean.90S.90N.df_1901-2000mean.dat , report land, ocean and combined land-ocean measurements. The land-ocean measurements are weighted to account for the fact that there is much more ocean area than land area (and other factors) and are presented as average global temperature. Applying the same method to the global average surface temperatures (latest available) as was done for the atmospheric temperature results in (there is less decline because of the influence of higher thermal capacitance) 21.8% (9 mo), 20.0% (10 mo) and 14.4% (9 mo) for Hadley, GISS and NOAA respectively. Thus all agencies are consistent in reporting the recent temperature decline. But understanding global climate does not come from examining a period so brief as the last decade, or even the last century. Any assessment of climate change that limits itself to a period that is a recovery from the LIA (Little Ice Age) while ignoring the decline in temperature that occurred during the change from the Medieval Warm Period (aka Medieval Climate Optimum) to the LIA is at best incomplete. Be aware that the ONLY predictors of significant Anthropogenic Global Warming are Global Climate Models (aka General Circulation Models) or GCMs. The only existing exact, correct computer of global climate is the planet itself. One of the outputs of this computer is recorded as temperature history. Temperature history, to those with even a minimum understanding of Dynamic System Theory, proves that net positive feedback does not occur in global climate. Without significant net positive feedback the GCMs do not predict significant global warming. Chris talks about glacier shortening but ignores that the glaciers started shortening about a century BEFORE the beginning of increase of substantial fossil fuel use and continued to shorten at the same rate with absolutely no indication of any influence from increased atmospheric carbon dioxide. This contributes to the growing realization that the GCM based predictions are faulty. Incidentally, imagine what was happening to glacier length during the period from the Medieval Climate Optimum (that Mann tried to claim never happened) until the lowest temperatures of the Little Ice Age. No one can be sure where the average global temperature will go from here. According to Vostok ice core and other data it has been warmer than now at other times during the Holocene (the last 11,000 or so years) and other interglacial periods so eventual temporary further rise is not out of the question. However, the change in pattern since 2001, the recent downtrend, and continued quiet sun are all indicating that the planet is in for a continuation of the cooling trend. The huge thermal capacitance of the oceans will cause the cooling to be gradual, as was the warming. The real issue is not the climate. There is no objective evidence that human activity has ever had or ever will have any significant effect on it. The real issue is the damage to human freedom and prosperity that can happen because of a few government financed alarmists and their followers who are unaware of a relevant part of science. Record low temperatures and newsworthy rare or early snow falls are starting to get attention. Unfortunately, it may require a drastic decline of temperature with accompanying crop failure and wide spread starvation for many to begin to realize that they may be missing something.
130665. chris at 05:28 AM on 15 November 2008
        It's the sun
        Re #192 and #203 On Roy Spencer: Roy Spencer has spent the better part of his "scientific" career as a staff scientist engaged in analysis of satellite Microwave Sounding Unit (MSU) data on tropospheric temperatures. This has been carried out for 15 or more years with a combination of incompetence (that borders on the fraudulent), and widescale propagandising for false interpretations outside of the normal channels of scientific communication. In recent times he's attempted to pull the wool over the eyes of the gullible and similarly misguided with a contrived mishmash of a notion relating to supposed natural internal variations in the climate system as a cause of 20th century global warming. The fact that Spencer is a creationist doesn't necessarily add or subtract to the fact that he's done disgracefully incompetent science for years, and that he attempts to "sell" falsehoods direct to the public through websites and the resources of anti-democratic organizations. After all there are a great many first-class scientisits that have strong religious beliefs. Unfortunately Spencers "style" of ceationism isn't really a religious belief...that class of "pseudo-Christian" fundamentalist "creationism" (wrapped up in the "intelligent design" "package") is really a political position. Sadly, it's very much in keeping with Spencer's apparent willingness to subvert scientific honesty in the service of creepy ideologies. My personal view is that Spencer is rather taken with the modern "pseudo-Christian" creationinist success in hiving of quite a large "rump" of the poorly educated, misguided and various assorted bullies, with what is obviously complete nonsense, and quite likes the fact that much of that same great "unwashed" are more than happy to swallow his anti-science nonsense on climate-related matters. As always in science it's about the evidence. Spencer has spent nearly 20 years making a complete hash of this, and that's why bone fide scientists and well-informed policymakes are less than thrilled with his "contribution"...
130666. chris at 23:03 PM on 14 November 2008
        Evaporating the water vapor argument
        Well yes, it's all about the evidence Mizimi, and not about trying to trap perceived "opponents" with semantic games! So it's pretty uncontroversial that enhanced atmospheric CO2 results in enhanced water vapour (this can be measured in the real world) as a feedback to CO2-induced warming. A warmer atmosphere promotes the enhanced atmospheric partitioning of water vapour. We can call this WV feedback AWV since it's an indirect a consequence of our CO2 emissions. However the effect of spraying water/water vapour into the lower atmosphere (from cooling towers and such like) has a minimal net contribution to greenhouse-induced warming, since this excess just comes straight out of the atmosphere within a very short period afterwards... So one needs to be clear about what "AWV" one (or two in this case!) is (are) talking about!
130667. Arkadiusz Semczyszak at 18:44 PM on 14 November 2008
        Arctic sea ice melt - natural or man-made?
        I’m come back to the subject - matter, precise “Arctic ice melt…” “natural or man-made…” I think: “fifty/fifty”… In the meeting AGU (XII 2007) the Scientists in University Cincinnati, Lamont Doherty Earth Observatory and University Maine (T.V. Lowell, M.A. Kelly, B. Hall., C.A. Smith, K. Garhart, S. Travis B.M. Goehring and G.H. Denton) (http://wattsupwiththat.files.wordpress.com/2007/12/uc-agu-greenland-dec-07-v45.pdf) was a demonstrate photography 6-8 cm diameter a fossil tree - from edge ice cover of the dome Istorvet, in Liverpool Land, Scoresby Sund (East Greenland - 70°50’N, 22°13'W) in situ with roots in > 8 cm a organic layer soil…The age by 14C a fossil tree = 1590 (±25) - 1040 (±30) yr BP (~ 400 -1015 AD), with high vegetation for period 840 - 980 AD. The Temperature of Air in cool East Greenland was a sufficient by vegetation of tree and shrubs on ~280 - 600 vertical m above the sea level… Brooks C.E.P., already in 1950 (Climate trough the Ages. Ernest Benn Limited, London. p. 395.) behind: Koch 1945, Petterssen 1914; say: - in period between V-VI - X-XI century, the Arctic Sea was do not have ice cover (…) or was to have firn-snow-semi-ice cover. For example a confirmation it is in: Berge J., Johnsen G., Nilsen F., Gulliksen B., Slagstad D., 2005. Ocean temperature oscillations enable reappearance of blue mussels Mytilus edulis in Svalbard after a 1000 year absence. Marine Ecology Progress Series, 303; 167-175.; and in: Story of Viking Colonies' Icy 'Pompeii' Unfolds From Ancient Greenland Farm - with Science, The New York Times 17.04.2008 - in 1935 the Arctic ice cover was likely as 2007. See “Greenland warming of 1920–1930 and 1995–2005” (GEOPHYSICAL Research Letters, VOL. 33, L11707, doi:10.1029/2006GL026510, 2006 33, L11707, DOI: 10.1029/2006GL026510, 2006) and http://klimat.files.wordpress.com/2007/03/salt_rec.jpg If it is true: what about the polar bears ‘et camarades’, in MVP. - dear IPCC-expert’s ? …and: “natural or man-made…” I remind You, that: “In the past two centuries, the Arctic has warmed about 1.6 degrees. Dirty snow caused 0.5 to 1.5 degrees of warming, or up to 94 percent of the observed change, the scientists determined.” + Solar Activity 14C - data from United States Geological Survey - see: Modern Maximum; and 1% S.A. for the different effects = even +/-2,3oC global temperature - und ours clear… …about professor Beck - historical CO2 - he’s right: Ice core - don’t say true - You must see in this paper: “Phytoplankton Calcification in a High-CO2 World” : M. D. Iglesias-Rodriguez, et al. Science 230, 336-340, 18 Apr 2008. freely downloadable from http://www.sb-roscoff.fr/Phyto/index.php?option=com_docman&task=doc_details&gid=418&Itemid=112,; and “A bi-proxy reconstruction of Fontainebleau (France) growing season temperature from AD 1596 to 2000” (www.clim-past.net/4/91/2008/) Fig. 2b; 3a - δ13C… My friend professor Jaworowski said: Ice core - here is too great chemical relation between H2O and CO2 - ice cores “say” probably only about history a remove CO2… Comparison the papers: “Rapid atmospheric CO2 changes associated with the 8,200-years-B.P.” Wagner et al 2002 (www.pnas.org/content/99/19/12011.full) fig 2. with fig. 3C (C4 %) in “Comparison of multiple proxy records of Holocene environments in Midwestern USA”: Baker et al. 1998, (http://people.ku.edu/~lgonzlez/NewFiles/Publications/Bakeretal98.pdf.) …and see: "A role for atmospheric CO2 in preindustrial climate forcing" by Thomas B. van Hoof et al. http://www.pnas.org/content/early/2008/10/03/0807624105.full.pdf P.S. Sorry by my Slavonic - Polish name and English Language…
130668. Mizimi at 08:12 AM on 14 November 2008
        Evaporating the water vapor argument
        Careful Chris...it looks like you're suggesting AWV might be having some effect after all.....
130669. Patrick 027 at 13:37 PM on 13 November 2008
        Arctic sea ice melt - natural or man-made?
        Actually, with regard to the horizontal scale of vorticity advection (and resulting vertical scale for differential vorticity advection): It's not just that the horizontal scale of temperature variation is affected. 'Before' that step, the pressure changes are also affected, in that the horizontal variation of vorticity advection directly causes horizontal variation in the divergence and thus in the pressure changes, so that there is a changing pressure gradient (or vertical variation of that for differential vorticity advection). A change in the pressure gradient is necessary if the adjustment to near geostrophy has both the geostrophic RV (or vertical variation of that) and actual RV approaching each other. Otherwise, without any horizontal variation in vorticity advection, the divergence could continue until the RV returns to the initial geostrophic RV. Sustained RV changes would be limited to the boundary of such a region. Of course accompanying temperature advection could have some other effect... On the other hand, sinusoidal horizontal variation would allow various changes to remain proportional to each other at each horizontal position.
130670. Patrick 027 at 15:05 PM on 12 November 2008
        Arctic sea ice melt - natural or man-made?
        ...continued... Notice that even if the wind is divergent, the relationship for dv/dx remains intact - that is, the variation along an isotherm of the component of the wind parallel to the temperature gradient - this acts to turn the temperature gradient rather than to change it's magnitude. --- Poleward geostrophic wind is convergent; equatorward geostrophic wind is divergent. If the wind is tending towards geostrophy, this pattern of divergence will change the vorticity, interestingly in the opposite direction that the corresponding planetary vorticity advection changes the relative vorticity (without divergence and friction, etc, AV = f + RV is conserved so changes in f must drive opposite changes in RV). Differential planetary vorticity advection can act as differential RV advection, but is not tied to temperature advection as RV advection is by geostrophic shear as described above (320,321). If planetary vorticity advection occurs through an entire column, then RV is created (or destroyed) over the whole column. The response for equatorward flow is increasing ageostrophic cyclonic RV, which drives divergence, lowering the pressure and the cyclonic AV until the RV and pressure come into balance; specifically the Laplacian of the pressure field has to increase, which corresponds to a relative horizontal maximum in pressure drop somewhere. Vertical compression occurs with the air becoming more stable; the isentropes stay near constant pressure near the 'top' of the column, so the pressure drops at each isentrope below, the most near the surface; this corresponds to adiabatic cooling. Horizontal variation in this cooling decreases the divergence and pressure fall at the surface while increasing it above - this being modified again by stability, if I'm not mistaken. Advection of a column over topography is also interesting; in this case, suppose one is moving a column of air downslope. Without any convergence, the pressure is falling at all levels in the column. Horizontal variation in this downslope motion (due to either the wind or the topography or both) drives convergence toward the larger downslope motions, increasing the pressure and vertically stretching the column. Convergence increases cyclonic AV, thus increasing cyclonic RV if f is not changing. Isentropes and pressure surfaces may rise nearly together near the top of the column but the pressure rises on isentropes near the 'dropping' surface. Hence there is warming near the surface, which, to the degree that it is horizontally varied (modified by stability, again, I think**), reduces the relative pressure rise at the surface, increasing convergence and cyclonic AV and RV near the surface, and having opposite effects above. Variations in downslope flow can initiate cyclogenesis...
130671. Patrick 027 at 13:48 PM on 12 November 2008
        Arctic sea ice melt - natural or man-made?
        continued from 320: If we are following the motion, subtract the velocity vector at the point we are following from the total wind field; the remaining component of the wind varies vertically and horizontally relative to a point we are following but is zero at that point. In x,y,p coordinates: For simplicity of illustration, let the frame of reference move with the point, so that the point of focus is 0,0,0. Let isotherms be aligned parallel to the x axis at 0,0,0; thus the temperature gradient is in the y direction, dT/dy. dT/dx = 0. ---- Let the vertical wind shear be equal to the geostrophic wind shear: Geostrophic zonal wind..... u = -(dF/dy)/f Geostrophic meridional wind v = (dF/dx)/f where F is the geopotential (z*g) of an isobaric surface. (The symbol for geopotential used is a capital greek letter, which is F in a symbol font). (z is the geometric height. In this context, g is given as a positive number and is approximated as constant with height; otherwise F = the integral of dz*g) ---- Vertical derivative of F: (a negative sign is used because p increases downward. -dF/dp = -d(z*g)/dp =~ g * dz/dp ...(the bulk of the mass of the atmosphere is in a thin enough layer that the vertical variation of g is a minor issue) = = g * dz/dm * dm/dp ...(where m is the mass per unit horizontal area) = dz/dm = 1/density = 'specific volume' = R*T/p, where R is the ideal gas constant expressed in terms of mass (which will then be different for different gases). and T is the temperature. ---- Vertical (geostrophic) wind shear: du/dp = -1/f * d(dF/dy)/dp = -1/f * d(dF/dp)/dy = -1/f * d(-R*T/p)/dy = 1/f * R/p * dT/dy ...(in isobaric coordinates, horizontal derivatives of p are zero. Any variations in R or an effective R, such as from very high humidity, can be treated by using 'virtual temperature'; In that case, though, adiabatic temperature changes may be a bit different, I think. This is relatively minor issue for Earthly conditions). Let A = R/(p * f) Thus the zonal vertical shear -du/dp = -A * dT/dy. Similarly, the meridional vertical shear -dv/dp = A * dT/dx The negative sign is used for clarity of visualization, because p decreases with increasing z. -du/dp has the same sign as du/dz. ---- Since dT/dx has been set to zero for initial conditions, -dv/dp = 0. ---- Horizontal wind variations: The change in the wind along isotherms, in the x direction: du/dx dv/dx The change in the wind along the temperature gradient, in the y direction: du/dy dv/dy --------------- In a given infinitisimal unit of time t, the changes are: -------- 1. Changes in thermal gradient and geostrophic shear: Notice that, at least initially (and that is the focus here), variations in u don't alter the temperature gradient because u blows along isotherms. The initial effect: dv/dy acts to change the spacing of isotherms; positive dv/dy decreases the thermal gradient dT/dy, etc. dv/dx acts to change the direction of the thermal gradient, by tilting isotherms in the horizontal, introducing a nonzero dT/dx value. These change the geostrophic vertical wind shear. --- 1a. From dv/dx: change in slope of isotherm dy/dx: dy/dx of isotherm = t*dv/dx resulting change in dT/dx: dT'/dx = initial dT/dy * -dy/dx of isotherm = dT/dy * -dv/dx * t change in geostrophic wind shear: -dv'/dp = A * dT'/dx = A * dT/dy * -dv/dx * t = -A * dT/dy * dv/dx * t --- 1b. From dv/dy: change in temperature gradient dT'/dy is inversely proportional to the change in isothermal spacing in the y direction. dT'/dy is equal to the gradient times the length dy' that the wind dv at y = dy pushes into the interval dy, per unit dy: dT'/dy = dT/dy * dy'/dy = dT/dy * -dv*t/dy dT'/dy = -dT/dy * dv/dy * t change in geostrophic wind shear: -du'/dp = -A * dT'/dy = A * dT/dy * dv/dy * t -------- 2. Changes in the vertical wind shear: The initial geostrophic shear advects the horizontal variations in the wind, differently over a vertical distance, producing some additional vertical wind shear. Notice that, initially, changes in the wind over y (du/dy and dv/dy) do not contribute to changing vertical shear because the geostrophic wind shear is parallel to isotherms; geostrophic -dv/dp is equal to zero. Using the initial geostrophic shear: -du/dp = -A * dT/dy --- 2a. From dv/dx: du/dp brings some wind dv' over to (0,0,dp) from dx' = -t*du thus dv' = -t*du * dv/dx and so the change in wind shear dv'/dp is: dv'/dp = du/dp * -dv/dx * t = -A * dT/dy * dv/dx * t -dv'/dp = A * dT/dy * dv/dx * t --- 2b. From du/dx: du/dp brings some wind du' over to (0,0,dp) from dx' = -t*du thus du' = -t*du * du/dx and so the change in wind shear du'/dp is: du'/dp = du/dp * -du/dx * t = A * dT/dy * -du/dx * t -du'/dp = A * dT/dy * du/dx * t ------------ SO: The changes in geostrophic wind shear by temperature advection: 1a. V'geo = -dv'/dp = -A * dT/dy * dv/dx * t 1b. U'geo = -du'/dp = A * dT/dy * dv/dy * t The changes in the wind shear by vertically-sheared momentum advection: 2a. V'adv = -dv'/dp = A * dT/dy * dv/dx * t 2b. U'adv = -du'/dp = A * dT/dy * du/dx * t ------------- Notice that -V'geo = V'adv, and both are due to dv/dx. The imbalance produced by V'geo is an ageostropic -dv'/dp that is the opposite of V'geo. V'adv is also an ageostrophic -dv'/dp. So both contribute equally to a total ageostrophic -dv'/dp, via the same dv/dx. Notice also that U'geo = U'adv. What does this mean? U'geo is from dv/dy, and U'adv is from du/dx. IF dv/dy = -du/dx, then the relationship between U'geo and U'adv is the same as that between V'geo and V'adv. dv/dy = -du/dx if the wind is non-divergent. THUS, Following the motion, the ageostrophic vertical shear produced by geostrophic vertical shear is twice that due to either the horizontal variation in temperature advection or to the vertically sheared momentum advection GIVEN strictly horizontal flow (x,y,p coordinates) and non-divergent winds; it isn't actually necessary for the total wind to be geostrophic, just the vertical wind shear. It is apparent from this conclusion that horizontal variations in the same mechanism are related; Following the motion, the vertical variation in vorticity advection produces ageostrophic vorticity at the same rate that horizontal variations in temperature advection (specifically, the rate of change of the Laplacian of the temperature following the motion) do. Additional effects can operate indepedently: ageostrophic vertical shear and divergence in the wind (including divergence in the geostrophic wind due to beta; PS the geostrophic wind is non-divergent when beta = 0 for (x,y,p) coordinates and maybe isentropic coordinates (I think**), but not (x,y,z) coordinates), and vertical transport of momentum; advection of planetary vorticity, friction, and diabatic heating/cooling (radiative and latent).
130672. chris at 10:51 AM on 12 November 2008
        Models are unreliable
        I see...a gear switch into tropospherical temperature measures now? Fair enough...however your problems on this issue are similar to those in relation to your cherrypicking of paleotemperature data (see posts #46, 48, 50, 52), your contrived misrepresentation of paleoCO2 data that is completely contradicted by the pukka scientific data (see posts #46, 48, 50, 52, 54), your dull cherrypicking of an incompetent paleotemperature "analysis" in a non-science magazine in which you pretended that the authors own rather fatal correction didn't exist (see posts #54, 58), your confusion over feedbacks…..and Milankovitch contributions (see posts #59, 62, 64)......and so on ..We've pretty much sorted out each of these (see posts #46, 48, 50, 52, 54, 58, 59, 62, 64)....so what about that tropospheric temperature data? There's a pretty serious problem with it I think we would agree. There's no question that the Earth's surface temperature is rising, and has done so rather dramatically since the mid 1970's. We can see this in the surface temperature record..or we can dispense with direct temperature records and construct a temperature record from the record of mountain glacier retreat…it’s pretty uncontroversial that it’s been getting significantly warmer, and rather quickly during the past 30-odd years. Basic atmospheric physics and associated climate models predict a significant tropospheric warming (it should be a bit larger than the surface temperature increase in response to enhanced greenhouse warming). However, the tropospheric temperature record from satellites (Microwave Sounding Units; MSU) and radiosondes (weather balloons) are giving some rather ambiguous data. What’s going on…? Your choice of the UAH record is interesting. The characters that compile this data have pursued a path of studied incompetence during the last 15 or more years, during which their early attempt to sell the notion that the troposphere was actually undergoing a cooling trend, was revised after it was pointed out that (a) their analysis was not sufficiently constrained to distinguish cooling from a warming consistent with physical expectations [ONE], (b) the method of averaging different satellite records introduce a spurious cooling trend [TWO], and (c) their incompetent disregard of orbital decay introduced another spurious cooling trend [THREE]. A little later it was shown (d) that MSU-2 showed a spurious cooling trend due to spillover of stratospheric cooling into the tropospheric temperature signal [FOUR], and later still it was pointed out that (e) the diurnal correction applied by Christy and Spencer (a sad litany of incompetence) was of the wrong sign and gave yet another spurious cooling trend [FIVE]. SO UAH is a rather dodgy source of data unfortunately. It’s a pretty scandalous record in fact. The RSS tropospheric data is likely to be more robust. But, unfortunately, however you look at it, the tropospheric temperature record from satellite measures [the radiosonde record has been shown to be highly contaminated by artefactual biases (see post #60 above)], is still poorly constrained. Despite Christy and Spencers’ assertions of “precision” in these analyses, they seem sadly inaccurate (and more so with Spencer and Christy’s litany of spurious adjustments towards cooling trends which has bedeviled the UAH analyses). Finally even Christy agrees that the tropospheric data worldwide is consistent with expectations from models, although he considers there is still a problem with the tropospherical temperature in the tropics. However that has been resolved recently, and there doesn't seem to be any substantive disagreement between the tropical tropospheric temperature trend as measured by satellites and predicted by models [SIX]. But it’s probably true to say that tropospheric temperature measures cannot really be used to make conclusive conclusions about either the agreement of satellite (or radiosonde) tropospheric temperatures with models or their disagreement. We need better tropospheric temperature measures I suspect. So if we’re really interested in knowing what the Earth’s surface temperature is doing in response to enhanced greenhouse forcing, we can look at the long term surface temperature record (around 100 years longer than the very short satellite tropospheric temperature record), and monitor the effects of warming (enhanced rate of sea level rise; large scale retreat of mountain glaciers; hugely increased rate of attenuation of Arctic sea ice…and so on). We can also note with respect to the troposphere, that the water vapour levels in the troposphere are increasing much as predicted by models [SEVEN], and alternative measures of tropospheric temperature that are not so affected by artifacts (not to mention incompetent mis-analysis; see above) give rather large warming trends (e.g. tropsopheric thermal wind measurements give maximum tropospheric temperature trends of 0.65 +/- 0.47 K per decade [EIGHT]). [ONE] B.J. Gary and S. J. Keihm (1991) Microwave Sounding Units and Global Warming Science 251, 316 (1991) [TWO] J. W. Hurrell & .K E. Trenberth (1997) Spurious trends in satellite MSU temperatures from merging different satellite record. Nature 386, 164 – 167. [THREE] F. J. Wentz and M. Schabel (1998) Effects of orbital decay on satellite-derived lower-tropospheric temperature trends. Nature 394, 661-664 [FOUR] Q. Fu et al. (2004) Contribution of stratospheric cooling to satellite-inferred tropospheric temperature trends Nature 429, 55-58. [FIVE] C. A. Mears and F. J. Wentz (2005) The Effect of Diurnal Correction on Satellite-Derived Lower Tropospheric Temperature, Science 1548-1551. [SIX] B. D. Santer et al. (2008) Consistency of modelled and observed temperature trends in the tropical troposphere. International Journal of Climatology 28, 1703 – 1722. [SEVEN] Soden BJ, et al (2005) The radiative signature of upper tropospheric moistening Science 310, 841-844; Santer BD et al. (2007) Identification of human-induced changes in atmospheric moisture content. Proc. Natl. Acad. Sci. USA 104, 15248-15253; Brogniez H and Pierrehumbert RT (2007) Intercomparison of tropical tropospheric humidity in GCMs with AMSU-B water vapor data. Geophys. Res. Lett. 34, art #L17912; Buehler SA (2008) An upper tropospheric humidity data set from operational satellite microwave data. J. Geophys. Res. 113, art #D14110; Gettelman A and Fu, Q. (2008) Observed and simulated upper-tropospheric water vapor feedback . J. Climate 21, 3282-3289 [EIGHT] R. J. Allen & S. C. Sherwood (2008) Warming maximum in the tropical upper troposphere deduced from thermal winds. Nature Geoscience 1, 399 – 403.
130673. Patrick 027 at 16:12 PM on 11 November 2008
        Arctic sea ice melt - natural or man-made?
        Regarding that last bit: If motion is strictly horizontal, starts out geostrophic and does not accelerate in response to ageostrophy (a completly artificial condition for illustrative purposes), and there is no variation in planetary vorticity f, and diabatic and frictional effects are set aside, and the wind is non-divergent (actually that must be true given geostrophic with no variation in f), then the result is that the wind can drive itself out of geostrophic balance; it does this in two ways that are apparently equal in magnitude according to the math. 1. Horizontal variations in wind velocity can advect temperature in such a way so as to change the horizontal temperature gradient within a layer of air, following the motion. This changes the vertical geostrophic wind shear. 2. The vary same horizontal variation in wind is such that the initial geostrophic wind shear advects those horizontal variations differently over a vertical distance, so that the resulting vertical wind shear through the layer of air, following the motion, is equal and opposite to the change in the geostrophic wind shear from 1. Hence, the resulting ageostrophic vertical shear is twice that of either 1. or 2. by itself. Horizontal variation in 1. can change the Laplacian of the temperature field. Horizontal variation in 2. can correspond to differential vorticity advection.
130674. Patrick 027 at 15:35 PM on 11 November 2008
        Volcanoes emit more CO2 than humans
        "Mystery Wave Strikes Maine Harbor" - interesting, yes. Likely related to climate change, or a multidecadal scale geological variance - the later seems unlikely, the former could be true in the sense that this may happen more often due to storm waves or whatever, but considering the (apparently) sparse number of such events, it's hard to find a trend, so unless this kind of thing could be expected as a result of something else, there isn't much to go on. "2004 Indian Ocean Tsunami Biggest in 600 Years" - "turns out to be more evidence of tectonic upset." - it was a tectonic upset, but not the kind for which a correlation to multidecadal climate trends would be expected. On the Arctic Oscillation - "Synchronized Chaos: Mechanisms For Major Climate Shifts" - I will have to read the paper referenced by the article. I suspect though that more is understood about how CO2 would affect climate than is about these kinds of things. The other two: they suggested global warming could be behind the trend in the AO, or at least some portion of it. Of course there is internal variability, and some unforced variation in AO will occur. (?) AO itself doesn't seem to cause much of a global average temperature change (? - if the change in temperature at midlatitudes is balanced by that in the polar region).
130675. Dan Pangburn at 12:34 PM on 11 November 2008
        Models are unreliable
        Chris is not only unaware of a well established part of science but apparently refuses to consider it. Dynamic Systems Theory is readily applied to global average temperature history and easily proves that there is no significant NET positive feedback. Instead we get parochial rationalizations and erroneous estimates of future temperature as calculated by flawed computer programs that mistakenly invoke significant net positive feedback. The current UAH satellite numerical temperature anomaly data (these data consist of the differences of lower atmospheric temperature from the 1979 thru 1998 average) are at http://vortex.nsstc.uah.edu/data/msu/t2lt/uahncdc.lt . According to these data, the AVERAGE GLOBAL TEMPERATURE for the first 10 months of 2008 is LOWER than the average from 2000 thru 2007 by an amount equal to 40.3% of the total linearized increase (NOAA temperature anomaly data from ftp://ftp.ncdc.noaa.gov/pub/data/anomalies/annual.land_and_ocean.90S.90N.df_1901-2000mean.dat) during the 20th century. Since 2000, the CARBON DIOXIDE LEVEL HAS INCREASED by 14.4% of the total increase since the start of the Industrial Revolution (from several sources which are given on the fourth graph in the Middlebury link at 41 above). None of the GCMs predicted anything remotely close to this decline of average global temperature with rising atmospheric carbon dioxide level. The GCMs are little more than glorified curve fitting to historical data and apparently have negligible predictive capability. It will probably need to get much colder for some people to realize that they may be missing something. As the carbon dioxide level continues to increase and the average global temperature doesn’t, many people are looking more and more foolish.
130676. chris at 09:56 AM on 11 November 2008
        Evaporating the water vapor argument
        Well yes Venus gives us an idea of what can happen when a greenhouse effect runs out of control. Of course it's not going to happen on Earth. However we do know the total amount of potentially accessible fossil fuels, and if all of this was dug up and burned along with all the methane hydrates and shales and tar sands and peat and all forms of coal and gas and oil, the total warming would be rather dramatic. New Scientist did a report a year or so ago of an analysis of the projected warming...around 12 oC I think. So if we continue burn fossil fuels with present gusto we do have the potential to add a rather awesome amount of CO2 (and water vapour) into the atmosphere, and this will add a rather large amount of thermal energy to the Earth's climate. And of course since the time to achieve the new equilbrium temperature lags the forcings by a significant amount, the Heat In will be out of balance with the Heat Out for a while until the climate system adjusts to fluctuate around a new equilibrium temperature that is higher than it would be without the additional greenhouse forcings. That's all pretty obvious isn't it!
130677. chris at 08:54 AM on 11 November 2008
        Water vapor is the most powerful greenhouse gas
        Hmmm...You've made some odd misinterpretations of my post again. If you read the two sentences following "THREE" in my post just above (#24) you can see that water vapour makes a significant effect. Since this is water vapour that re-equilibrates in the atmosphere in response to anthropogenic CO2-induced warming it can be classed as anthropogenic water vapour (AWV). And I certainly didn't say that "the atmospheric total of WV remains more or less constant because of precipitation". If you read the two sentences following "THREE" in my post just above, it states: "AS the entire troposphere warms under the influence of cumulatively enhanced CO2 concentrations, so the atmospheric water vapour concentration rises." I'm not sure how you can interpret a statement that the WV rises as meaning that "the WV remains constant"! Of course the atmospheric WV fluctuates. It varies according to the local atmospheric temperature (and pressure). However on average the amount of atmospheric water vapour rises as the atmospheric temperature rises on average in a warming world. This can be measured in the real world. And any water vapour that doesn't partition into the atmosphere according to the local temperature and pressure just falls right out again as precipitation. If we doubled the amount of water that we pumped into the near ground atmosphere that doesn't change the fact that it is ultimately the local atmospheric temperature and pressure that governs the amount of water vapour in the atmosphere. Anything else that's pumped up there just falls right out again as precipitation. The NOAA site gives a pretty basic description although it's a bit out of date with respect to the determination of tropospheric water vapour in response to greenhouse warming.
130678. chris at 08:18 AM on 11 November 2008
        It's the sun
        Not really Quietman. It wouldn't make a noticeable difference! And in fact you've got it the wrong way round. If we removed the catalytic converter a tiny proportion of the CO2 otherwise pumped into the atmosphere would remain unoxidised to CO2 (and left as hydrocarbon or carbon monoxide). Since this tiny, tiny amount is from 13C-depleted fossil fuels, it would RAISE the 12C/13C ratio (since we would be failing to add to the atmosphere a tiny, tiny amount of 13C-depleted CO2). Of course that's all academic. The point is that we know very well from at least three seperate types of measurement (including the measurement of carbon isotopes in CO2) that the massive increased atmospheric concentrations of carbon dioxide, and the massive partitioning of carbon dioxide into the oceans, is the result of massive digging/pumping up and oxidation of long-sequestered fossil fuels.
130679. Mizimi at 06:43 AM on 11 November 2008
        Evaporating the water vapor argument
        Venus? A lot nearer to the sun than the earth so TSI is a lot higher. CO2 concentration (if I remember rightly) is 30,000 times greater. Galileo probe showed an enormous amount of IR being retained by sulphuric acid cloud cover. No atmospheric water as it has all been dissociated and blown away ( Venus has virtually no magnetic field. Not a good comparison. So, no, Venus gives us no clues at all.
130680. Mizimi at 06:37 AM on 11 November 2008
        Water vapor is the most powerful greenhouse gas
        You seem to be arguing that AWV has virtually no effect but as soon as CO2 induces increase in WV by warming the atmosphere a fraction of a degree there is a WV 'positive feedback' which is admitted...even when the amount is unquantified and probably quite small itself? And that somehow, despite adding AWV, the atmospheric total of WV remains more or less constant because of precipitation; yet we know it doesn't. It fluctuates all the time. "As the temperature of the atmosphere rises, more water is evaporated from ground storage (rivers, oceans, reservoirs, soil). Because the air is warmer, the relative humidity can be higher (in essence, the air is able to 'hold' more water when its warmer), leading to more water vapor in the atmosphere. As a greenhouse gas, the higher concentration of water vapor is then able to absorb more thermal IR energy radiated from the Earth, thus further warming the atmosphere. The warmer atmosphere can then hold more water vapor and so on and so on. This is referred to as a 'positive feedback loop'. #However, huge scientific uncertainty exists in defining the extent and importance of this feedback loop.# # As water vapor increases in the atmosphere, more of it will eventually also condense into clouds, which are more able to reflect incoming solar radiation (thus allowing less energy to reach the Earth's surface and heat it up).# The future monitoring of atmospheric processes involving water vapor will be critical to fully understand the feedbacks in the climate system leading to global climate change. #As yet, though the basics of the hydrological cycle are fairly well understood, we have very little comprehension of the complexity of the feedback loops.# Also, while we have good atmospheric measurements of other key greenhouse gases such as carbon dioxide and methane, #we have poor measurements of global water vapor, so it is not certain by how much atmospheric concentrations have risen in recent decades or centuries,# though satellite measurements, combined with balloon data and some in-situ ground measurements indicate generally positive trends in global water vapor. http://lwf.ncdc.noaa.gov/oa/climate/gases.html
130681. Quietman at 06:34 AM on 11 November 2008
        It's the sun
        chris That is correct. SO by removing the catalytic converter we would reduce CO2 output and lower the 12C/13C ratio.
130682. Patrick 027 at 06:22 AM on 11 November 2008
        Arctic sea ice melt - natural or man-made?
        Actually, if the diabatic residual meridional circulation exists, the coriolis effect acts on that to accelerate zonal winds, opposing the effect of southward eddy IPV flux. The coriolis effect acts on the Ferrel cell motion to oppose the effect of momentum flux convergence and to reduce the vertical wind shear, which will also bring the wind toward geostrophic balance with the reduced thermal gradient due to eddy heat fluxes. ----- Another way to look at the horizontal and vertical scale relationships: As illustrated above (independently of the IPV concept), following the motion of the air at one level, increasing cyclonic vorticity advection with height (or decreasing anticyclonic vorticity advection with height) creates an imbalance that drives either divergence above or convergence below or both; and *1. one (convergence below or divergence above) will drive the other by changing the pressure at all levels in an atmospheric column (assuming hydrostatic balance is at least approximately maintained). This produces by mass continuity (while remaining close to hydrostratic balance) upward vertical motion (in x,y,p coordinates; upward vertical motion is negative Dp/Dt). *2. The upward vertical motion causes adiabatic cooling as isentropes are displaced vertically (diabatic heating such as by latent heating will reduce that). *3. This change in temperature changes the vertical pressure gradient. *3 only happens if the air is stable and is proportional to that stability; with constant potential temperature with height, the temperature at any given pressure level remains the same. *4. The horizontal pressure gradient changes associated with the adiabatic cooling, modulated by stability, intensifies the relative low pressure above and reduces it below, thus reducing the convergence below and increasing it above, as the divergence pattern acts to vertically contain the voriticity pattern, against the tendency for vorticity (and associated curvature of the horizontal pressure field) changes to spread vertically by *1. HOWEVER, in order for *2, via *3, to cause *4, there has to be a curvature in the induced temperature anomaly field - the Laplacian of the temperature must be nonzero - in other words, If the vertical variation in vorticity advection were constant over some horizontal region, and the stability is also constant as is the absolute vorticity at a given vertical level, then the adiabatic cooling is constant and thus has no horizontal temperature gradient associated with it, and no horizontal pressure variation and no geostrophic vertical wind shear. Aside from variations in AV and stability, it is the horizontal variation in the vertical variation of vorticity advection that allows the adiabatic warming or cooling to limit the vertical extent of induced vorticity. Hence, larger vertical extents are supported by larger horizontal scales. The vertical variation in vorticity advection is 'differential vorticity advection'. When does differential vorticity advection (DVA) happen? 1. vertical wind shear across a vertically-constant vorticity gradient, including the planetary vorticity gradient. 2. constant wind across a vertically-varying vorticity gradient. 3. some combination of wind shear and variation of vorticity gradient with height. But notice that if 2 is the case, this only moves an entire atmospheric column. Thus, there is no level to be found at which, following the motion of the air, there would actually appear to be vorticity advection above or below. 2 by itself does not cause any divergence or vertical motion. However, the vertical variation in the relative vorticity gradient would, assuming near geostrophy, be related to temperature variations. Horizontal variations in temperature advection will drive divergence and vertical motions. Specifically, cyclonic RV increasing with height implies a cold temperature anomaly that decreases away horizontally (positive Laplacian of temperature) If the wind does not vary horizontally, the temperature pattern is advected in whole and this by itself does not cause any imbalance. If there is varyation in the wind over horizontal distances, then the temperature advection pattern can produce changes in the horizontal temperature gradient following the motion. Specifically it is the convergence of the change in temperature gradient FOLLOWING the motion that drives upward motion. It turns out that because of the relationship between geostrophic vertical wind shear ('the thermal wind') and the horizontal temperature gradient, the effect of differential relative geostrophic vorticity advection by geostrophic winds, FOLLOWING the geostrophic motion, is the same as the effect of the changing temperature gradient, FOLLOWING the geostrophic motion, so that - (?)the combined effect on vertical motion and convergence and divergence is twice the effect of either by itself (?) - I think; - this relates to something called the Q vector.
130683. John Cross at 02:32 AM on 11 November 2008
        A Great Science Fiction Writer Passes - Goodbye Dr. Crichton
        Quietman: I also liked the 13th Warrior - although it got a little over the top at the end. I did not like Prey at all. It is possible that since I am involved in a field close to fluid mechanics I am more critical of some of the fluid parts than others would be. Anyway, I did not find it his best work. I have not read State of Fear - but I have read enough excerpts to get an idea. I am sure that if one keeps in mind that it clearly is a work of fiction then it would appeal to some people. Regards, John
130684. chris at 23:34 PM on 10 November 2008
        It's the sun
        Chemical catalysis has zero effect on 13C. There is a fundamental difference between chemistry (catalysed or uncatalysed bond making and breaking) and nuclear physics (extremely high energy transformation of the structure of atomic nuclei). So fossil-fuels have highly depeleted 13C relative to the natural abundance of 13C, since plants have a significant "preference" for the uptake of 12C CO2 over 13C CO2 when they draw CO2 out of the atmosphere. As the plants are "fossilised" into coal, oil and natural gas, shales, peat and so on, they retain this highly depleted ratio of 13C/12C. 13C and 12C cannot interconvert by chemical processes. When the fossil fuel is returned to the atmosphere by burning the 13C-depleted CO2 is at long long last returned to the atmosphere, and the 13C/12C ratio of atmospheric CO2 drops. This doesn't happen to any significant extent with CO2 released by volcanoes, since (first) volcanoes and tectonic activity in general doesn't release much CO2 as we can observe by inspecting the atmospheric CO2 records at high resolution for 1000's of years, and at low resolution for millions of years. Sedimented carbonates, and even the shells of marine organisms give rise to very, very small differences in the 13C/12C ratio, and these relate more to the physicochemical "fractionation" as a function of temperature. Since 13C is essentially unaffected by any processes outwith particle accelerators, nuclear reactors and so on, in which nuclear transformations can take place, 13C is effectively inviolate in the Earth [***]. So as we burn fossil fuels a 12C carbon remains as a 12C isotope and likewise a 13C carbon atom. This occurs if the CO2 is produced by direct oxidation of carbon or hydrocarbon, or if a small amount of the hydrocarbon is left partially unoxidised or in the form of carbon monoxide, and is subsequently oxidised "to completion" within a catalytic converter. The answer to your specific question of post #207 is yes..you would measure the same 13C/12C raio in airborned hydrocarbon and carbon monoxide, whether or not these were vapourized directly into the air or fully oxidised to carbon dioxide within a catalytic converter. [***]The unstable carbon isotope 14C is produced in very small amounts in the upper atmosphere by the action of gamma rays, at much lower energies than required to produce the stable isotope 13C, and this provides the basis of using 14C decay as an "atomic clock" in radiocarbon dating. Note that the atmospheric 14C content can be used to distinguish fossil-fuel-derived carbon from deforestation-derived carbon, since the 1/2 life of 14C radioactive decay (a bit under 6000 years) is long relative to the life of trees (except for the most ancient of these like the bristlecone pines in the west of the USA!), but very short relative to the time that fossil fuels have lain undistrubed underground. This is somewhat complicated by the fact that just the short period of nuclear device testing in the 1940's through the 1960's has produced quite a significant spike in the atmospheric 14C content, and needs to be corrected for...
130685. Patrick 027 at 16:23 PM on 10 November 2008
        Arctic sea ice melt - natural or man-made?
        Potential point of confusion: When I described the effect of vertical variations in vorticity advection, I mentioned that an 'injection' of cyclonic vorticity concentrated at some level would lead to divergence at that level (and then leading to convergence at other levels, etc.). Convergence would occur if vorticity is removed from some level (causing divergence at other levels, etc.). Thus, a vorticity maximum that is being transported relative to air at other levels (rather than along with the whole column, in which case everything stays balanceds and there is no convergence or divergence except for changes in planetary vorticity or topography, etc.), while inducing features above and below that would follow it, should also be slowed down relative to the basic state wind that carries it along, by the process of inducing those motions above and below. But how can that happen with an IPV anomaly, since IPV is conserved following the motion in adiabatic processes? Is it necessary to include the Rossby-wave propagation to resolve this? ---- PS from Cushman-Roisin, p.87: The group velocity of barotropic Rossby waves (just due to the beta effect, gradient of AV is to the north): For longer wavelengths, the group velocity is to the west; for shorter wavelengths, to the east; the divide between the two occurs at the maximum frequency for a given meridional wavenumber; at which point the group velocity is due north or south; for waves with phase propagation to the the northwest or southwest, the meridional component of the group velocity is to the south or north, respectively (in the opposite direction of phase propagation). My earlier 'work' (comment 296) on Rossby wave frequency suggested that the frequency can be arbitrarily large; but this is not actually true; there is an upper limit. I'm not 100% sure but it seems as if the Cushman-Roisin derivation, pp.83-87, includes the effects of divergence; this may be what places an upper limit on frequency, then. The limit of westward phase speed at arbitrarily large wavelengths is equal to the product of beta and the square of the external Rossy radius of deformation; the highest frequency allowed is the product of beta and the external Rossby radius of deformation divided by 4*pi. (In these derivations it was assumed there was no RV contribution to the vorticity gradient.) Interestingly, the lowest frequency allowed for inertio-gravity waves is f/(2pi), the frequency of inertial oscillation (when RV = 0); and that limit is achieved at infinite wavelength (Cushman-Roisin, p.83). According to Cushman-Roisin, it was assumed in the derivation of Rossby wave formulas that the expression for frequency would be less than the minimum frequency of inertio-gravity waves. The highest frequency Rossby waves actually are not quite the longest wavelengths in this formulation; they occur with meridional wavenumber = 0, so that the phase lines are oriented north-south, the wave phase propagation is due west, the zonal wavenumber is 1/(external Rossby radius of deformation), so the wavelength is equal to 2pi*(external Rossby radius of deformation). ---- EP flux and eddy IPV flux: Specifically (Holton pp.323,327): The EP flux is a vector in a vertical meridional plane (at least in this application), where the northward component is proportional to -u'v' (the southward eddy zonal momentum flux) and the upward component is proportional to v'T' (the northward eddy temperature flux). Thus v'T' decreasing with height and u'v' increasing northward (implying eddy zonal momentum flux DIVERGENCE which would tend to slow the average westerly winds) would tend to lead to EP flux CONVERGENCE (I say 'tend to' because those quantities have to be multiplied by some coefficients to actually get the EP flux, and some of those can vary). The EP flux convergence corresponds and is proportional to a southward eddy flux of IPV (Holton p.327) which makes sense since increasing RV to the south and decreasing RV to the north implies an average slowing of westerly winds and a divergence of zonal momentum flux, and decreasing v'T' with height implies an average decrease in static stability to the north and the opposite to the south. The actual tendency of the eddy fluxs and EP flux in mid-to-high latitudes (Holton p. 324, pp.319-325) is: 1. generally for poleward temperature flux v'T' between the subtropics and polar latitudes, which increases with height from the surface to some low level in the troposphere, but after that a general decrease with height within the troposphere, a minimum near the tropopause (at least in winter, or more clear in winter** in Fig 10.3), and increasing again somewhat into the stratosphere in winter (**Fig 10.3 - I'm assuming some similarity between southern winter and northern winter, and for the two summers, but of course there will be differences too). 2. generally poleward zonal momentum flux over the subtropics and some equatorward zonal momentum flux over subpolar latitudes, so that there is a zonal momentum convergence between subtropics and subpolar latitudes, and this is generally a maximum near the tropopause (where there is a maximum in jet stream velocity). Thus in the midlatitudes there tends to be eddy momentum flux u'v' convergence increasing with height within the troposphere (and decreasing above that at least to some point), and poleward eddy heat flux that generally decreases upward within the troposphere except near the surface (the lower near surface values are probably due to frictional slowing of the winds, I think). The contributions to EP flux divergence: the momentum fluxes would lead to EP flux divergence especially near the tropopause; generally the effect of thermal fluxes dominates, however, so in most of the troposphere the EP flux is convergent, except for some significant divergence next to the surface (also due to thermal fluxes). It approaches zero divergence around the tropopause level. The effect of that is to slow the average zonal momemtum, except just above the surface where it could accelerate the average zonal momentum. The coriolis effect would act on this perturbation to acceleration the motion poleward in the mid troposphere and equatorward just near the surface. The overturning that this describes is a diabatic circulation (rising air is being heated by latent heating and/or radiation, sinking air is being cooled by radiation) and is in a way an extension of the Hadley cell. But wait! Where did the midlatitude Ferrel cell go? Actually, the EP flux 'includes' the adiabatic portion of the Ferrel cell, which dominates over the 'residual meridional circulation' (p.323) in the Eulerian zonal mean. The adiabatic portion is rising poleward and sinking over the subtropics. In the full Eulerian mean, the vertical distribution of zonal momentum convergence perturbs the average motion, the eddy heat and the coriolis effect acts on that to produce meridional circulation in the same direction as the ferrel cell, and the poleward eddy heat flux causes a similar overturning. (Having trouble with that? So did I!)
130686. Quietman at 15:59 PM on 10 November 2008
        It's the sun
        Or put another way, would you measure the same C13/C12 ratio in airborne HC and CO?
130687. Quietman at 15:57 PM on 10 November 2008
        It's the sun
        ps A byproduct is SO2.
130688. Quietman at 15:54 PM on 10 November 2008
        It's the sun
        chris We use a series of catalysts inside every catalytic converter to transform HC, CO and NOx into H2O and CO2, starting in CA in 1974 and nationwide after 1975 depending on engine size. Almost all passenger vehicles were equipped with cats by 1978. Then there are the industrial stacks. The converters for stacks are also aimed at producing CO2 and H20. This is mandated by the EPA. So what effect does the cat have on C13?
130689. Quietman at 15:32 PM on 10 November 2008
        Volcanoes emit more CO2 than humans
        Mystery Wave Strikes Maine Harbor By Robert Roy Britt, LiveScience Managing Editor, 04 November 2008: "A series of large, unexpected tsunami-like waves as high as 12 feet struck Maine's Boothbay Harbor on Oct. 28, and there's still no explanation for what caused them."
130690. Patrick 027 at 12:20 PM on 10 November 2008
        Arctic sea ice melt - natural or man-made?
        According to Bluestein (p.193), the horizontal scale L of an IPV anomaly and the vertical scale H of the RV anomaly it induces, are related by the formula for the Rossby radius of deformation: L is proportional to NH/f (PS I'd suspect that a more general relationship would replace f, the planetary vorticity, with the basic state AV ?). or H is proportional to L*f/N N is the buoyancy frequency (basic state) and I believe it is proportional to the square root of stability (where stability = 1/S). I explained why static stability limits vertical penetration of induced RV (Bluestein p.193 - specifically H is proportional to the square root of S). How would the length scale work? Well, conceptually, for a given static stability, the horizontal temperature gradient increases with increasing slopes of isentropic surfaces. The thermal gradient must balance the vertical shear that limits the vertical extent of the RV. A given slope over longer horizontal distance implies a greater vertical displacement of an isentropic surface relative to basic state conditions. --- An IPV anomaly distorts the isentropes from their basic states; the greatest distortion being closest (in vertical and horizontal) to the IPV anomaly center. For a cyclonic IPV anomaly, isentropes are 'pulled' upward towards it from below and downward from above. Notice that if this anomaly is moving, say, eastward relative to the air above and below, adiabatic motion above and below, in response to the passing IPV anomaly, follows the isentropes; as the IPV anomaly approaches, what happens is (mostly?) as described in the second long paragraph of comment 313, which started "Now what happens when there is vorticity advection that varies with height?". There is convergence at levels above and below, vertical motion toward the level of the anomaly; the reverse happens as the IPV anomaly passes and moves away. What about if the IPV anomaly is moving differently with respect to the air above and below? If there is westerly (eastward) shear throughout, the air above approaches the IPV anomaly from the west. Thus what happens above the IPV anomaly is reversed east-to-west from what was described above. In that case, vertical motion is downward both above and below the IPV anomaly level to the west and upward both above and below to the east of the anomaly. Looking only in a planar cross section, it would appear that the air only approaches the level of the anomaly and then moves back; however, the air also moves around the anomaly cyclonically; if there is a basic state temperature gradient - warmer to the south - then the isentropes slope upward to the north, so for example, the air below the IPV anomaly to it's east, approaches the IPV anomaly and rises, and moves north; The northward motion may not slope up as much as the isentropes because it pushes the isentropes with it (horizontally-concentrated warm air advection - creating eddy potential energy from basic state potential energy), but it may slope in the same sense to some degree, allowing some air to rise above the IPV anomaly level while to it's east (after having moved into colder surroundings, so that it is rising in a thermally-direct fashion (out of a dent in the isentropic surface created by the horizontal motion): eddy potential energy converts to eddy kinetic energy); it then (with some geostrophic adjustment) accelerates to the east with the upper level air. And so on for the sinking motion west of the IPV anomaly. Throw in tilting anomalies with height, etc...: A growing baroclinic wave (extratropical cyclones). Now if there is a basic state IPV gradient, then the IPV anomaly may propagate against the wind, ... etc... Especially if the wavelength of the anomaly is large... (It would be interesting to consider how variations in N, H, wind shear, IPV gradients, AV, and wavelengths combine to determine whether a baroclinic wave can grow and how fast). Actually, much of the isentropic IPV gradient (besides that 'at the surface' ?) is concentrated near the tropopause and stratosphere; for isentropic surfaces that cross the tropopause, the stratospheric portion can be judged as the region with larger IPV. My impression is that some of baroclinic instability can be understood in terms of undulations in the tropopause corresponding to tropopause level IPV anomalies, and surface temperature variations corresponding to IPV anomalies 'at the surface'. But there is some basic-state IPV gradient (increasing toward the poles generally) within the troposphere).
130691. chris at 11:43 AM on 10 November 2008
        Evaporating the water vapor argument
        Yes there is a limit to incoming electromagnetic radiation. I expect that there is an upper temperature limit. Perhaps Venus might give us a clue as to the upper temperature limit that is possible due to the "amount of energy that can be "retained" by GG effects". And yes, we might very well not find that to our liking. Of course GG's are "adding" something. They are adding thermal energy to the Earth's atmosphere, surface and oceans.
130692. chris at 11:35 AM on 10 November 2008
        Water vapor is the most powerful greenhouse gas
        nope, you're still not getting it. First of all I did say that the tiny excess amount of water vapour with its short residence time might have an effect, but this will be a small steady state one, since the excess water vapour rather quickly precipitates from the lower atmosphere. In post #14 we calculated that the steady state effect might be equivalent to something under 1 ppm of additional atmospheric CO2. Remember that atmospheric CO2 doesn't fall out of the atmosphere. As we pump CO2 into the atmosphere it accumulates day by day, month by month, year by year. That can't happen with water vapor. So any tiny additional amount of water vapour we pump into the atmosphere that supplements that vastly larger amount from natural evaporative/precipitation results in a tiny steady state increase in whatever amount of warming results from the natural evaporation. Of course we do know that as the troposphere warms throughout its entire height, so the saturation point of water vapour increases (warmer air holds more water vapour). And so there is a net accumulation of water vapour in response to CO2-induced atmospheric warming that does lead to a cumulative increase in atmospheric water vapour. We know this occurs, first because it's simple physics and secondly we can measure it in the real world. In short: ONE: the CO2 we pump into the atmosphere stays there (except for the amount that partitions into the oceans and is absorbed by the terrestrial environment). Therefore atmospheric CO2 concentrations rise cumulatively (and very very quickly now). TWO: the water vapour that we pump into the atmosphere is a tiny supplement to the natural evaporative/precipitation cycle, and since this comes straight out of the lower atmosphere within a week or two it can (a) have only a very small effect and (b) caanot be cumulative. THREE: AS the entire troposphere warms under the influence of cumulatively enhanced CO2 concentrations, so the atmospheric water vapour concentration rises. This element (the water vapour feedback to enhanced greenhouse warming) is cumulative, and does provide a very significant supplement (a feedback or amplification) to the primary CO2-induced warming.
130693. chris at 11:18 AM on 10 November 2008
        It's Urban Heat Island effect
        How silly Mizimi. We're not taking a picture of you in Times Square. We're taking a picture at night of the cities and built up areas of the Earth. If we "left the camera running and took 365 photos on ONE frame", the lights of New York and the great connurbation of the Eastern US seaboard are NOT going to disappear are they? ..and nor will the lights of the great cities and connurbations spreading Westwards from the East coast....nor the cities of Western coastal USA...nor the great built up areas down the East coast of South America (Rio; Buenos Aires...)...nor the great cities and connurbations of Western Europe...nor the equivalent cities and connurbations of Japan and the East and S. east coast of China...nor the cities and connurbations scattered around the inhabited coastal regions of Australia...and so on... ...and lights are not magically going to appear in Arctic and Alaska, the vast Northern territories of Canada and Serbia, the empty regions of Australia, North and Central Africa and so on... The Urban Heat Effect is by definition an URBAN heat effect. Urban areas are identifiable by night time satellite photos since they are lit up. The greatest density of light relates to the greatest density of urban infrastructure. The rather obvious conclusion from John Cook's juxtaposition of global surface temperature anomaly and nightime satellite image is that most of the vast areas of the world that have undergone rather large warming in the years to 2005 are those that are very far away indeed from urban centres. In fact one doesn't really need John Cook's night time satellite photo to make that conclusion. One only needs to inspect the global surface temperature anomaly image with a reasonably informed understanding of human population geography to see that the urban heat effects can't have made significant contribution to global surface warming... ...but the satellite photo is an excellent aide to those that might not be too clued up on the geographical distribution of industrialised human populations. ...and it's a beautiful photo, so kudos to John Cook for a very informative juxtaposition...
130694. chris at 06:59 AM on 10 November 2008
        It's the sun
        re #202 You need to explain your request. All 13C is "natural" (unless it's produced in a particle accelerator). What do you mean by the "current source of 13C" and the "natural source of 13C"? And what "catalysts" are you referring to? 13C is a carbon isotope and isn't affected by catalysts.
130695. Mizimi at 06:40 AM on 10 November 2008
        Water vapor is the most powerful greenhouse gas
        1. The WV does indeed mostly stay in the lower atmosphere, but since that is the nearest to the radiating body ( the earth)it has a proportionately greater effect (exponential? the first molecule radiates in all directions and some of that is captured by the next and et seq) and whilst the amount may be small in relation to the total, the same can be said for CO2. And you don't appear to accept that when that WV is in the atmosphere ( for however long) it IS achieving some level of greenhouse effect. 2. The WV column thro' the atmosphere is a gradient, most at the bottom of the column. This re-inforces my view that its greatest effect is at lower levels. The current amount of WV being 'added' by man is larger than the CO2 and logically has a greater warming effect. 3. With regard to the absorbtion of IR I will go re-check. But by your figures there is 5x more WV than CO2 and together they account for a 33C rise in temp. This makes WV twice as powerful as CO2. 4. I have preliminary data on world water usage which shows a rising trend from 700 to 2000 cubic kilometres from 1950 t0 2005 - - this is evaporated water from all sources. Interestingly there is a marked increase from 1980 -1990 of around 30% ( 1850 to 2360 ck)just around the time the GMT started to rise sharply. I don't see this as co-incidence.
130696. Patrick 027 at 06:33 AM on 10 November 2008
        Arctic sea ice melt - natural or man-made?
        Wrapping up some details: To be precise, IPV is equal to the negative of the isentropic AV divided by dp/d(theta) * 1/g, where g is the acceleration due to gravity, theta = potential temperature. (Bluestein p.190) Let S = dp/d(theta), so S is inversely proportional to static stability. IPV = - AV * g/S. S/g is actually the mass per unit theta per unit area, and so this formulation of IPV is equal to AV per unit mass per unit area within an isentropically-defined layer. To make comparable to barotropic PV, we could let barotropic PV = AV * g/(surface pressure); this is AV per unit mass per unit area of the whole fluid layer; or for a nearly incompressible fluid like water, barotropic PV = AV/(H*density), where H is the depth of fluid.
130697. Quietman at 02:48 AM on 10 November 2008
        A Great Science Fiction Writer Passes - Goodbye Dr. Crichton
        The 13th Warrior (Eaters of the Dead) was my favorite movie but I had some trouble getting into the book. Jurrasic Park my favorite book by him (the movie was good but not as). Then there was Prey and State of Fear, both excellent but somewhat alarmist.
130698. Patrick 027 at 14:51 PM on 9 November 2008
        Arctic sea ice melt - natural or man-made?
        I did several internet searches a week or two ago on the subject of annular modes, waves, and troposphere-stratosphere interaction. Here's what I remember at the moment: The stratosphere can have an effect on the troposphere (besides thermal/radiative). Conditions in the stratosphere affect how or if various waves in the troposphere can propagate. But conditions in the troposphere affect those waves - their production, etc. Annular modes may/might occur due to tropospheric mechanisms even without stratospheric feedbacks. But the stratosphere can play a role. A component of climate change 'projects onto' the annular modes - An aspect of the climate change with global warming is similar to a change in the AO or NAM index (NAM = Northern Annular Mode, I think; and I think it's the same as the Arctic Oscillation, AO). Cliamte change may affec the relationship of NAO to NAM. Ozone depletion affects SAM? From my own simple logic, I would guess the direct thermal response of the stratosphere to solar forcing would be (besides a generally warmer stratosphere and above) a warmer summer and low-latitude upper stratosphere relative to the winter polar stratosphere; whereas increasing CO2, etc, should (aside from generalized cooling) tend to cool those parts that are warmer relative to other parts - thus, the lower stratosphere of midlatitude winter would cool relative to the low-latitude and high-latitude parts of the same. The cold winter polar stratosphere would be relatively warmer in comparison. HOWEVER, from IPCC graphs (Ch 9 in AR4 WGI, as I recall), the modelled distribution of the temperature response (aside from the marked difference in the overall trend) is more similar between solar and GHG forcing. Must be the dynamic feedbacks...but how do they work? If the stratosphere can affect the troposphere, then perhaps the mesosphere can affect the stratosphere, and so on (well, of course they do, it's just a question of in what way and the significance of it). Changes in solar forcing have a large effect on the thermosphere in particular. On the other hand, I've gotten the impression that observations so far indicate a multidecadal (?) thermospheric cooling, along with the stratosphere and mesosphere, suggesting GHG forcing has been dominating the trend even up there. So the solar UV and shorter wavelengths and other energies may have a 'special' role to play by way of troposphere-stratosphere-etc. interaction, but I don't see a reason to suspect it explains a sizable chunk of what would otherwise be attributed to GHGs, etc..., at least and especially the later part of the 20th century - but then again, there is a lot I haven't read and don't know. (and what about winds and currents in the ionosphere?) So if you find something... (but remember how much work supports the conclusion that GHG forcing has been dominant).
130699. Patrick 027 at 14:27 PM on 9 November 2008
        Arctic sea ice melt - natural or man-made?
        I think one necessary condition for both barotropic and baroclinic instability is that the waves/eddies have to be moving such that there is at least one level (in the horizontal or in the vertical, respectively) - a critical level - at which the basic state wind is moving with the instability phase speed. --- waves can grow, propagate, be emitted by a disturbance, reflect, refract, absorb, over-reflect (I think that's analogous to stimulated emission of radiation), and also, they can break. I think breaking occurs when material lines reconnect (which requires mixing) *?*. Notice that for adiabatic motion, contours of IPV on an isentropic surface are material lines on that surface. They are also isentropes on an IPV surface, and those are also material lines on an IPV surface. Reconnection of these contours can result in cut-off eddies (like a cut-off low); this can occur from diabatic processes which can produce and destroy IPV. Waves can also interact and produce waves in other parts of the spectrum or produce disturbance that radiate other waves, etc... ---- On wave-mean interaction: Earlier I discussed interaction between barotropic Rossby waves and variations in the basic state wind, such as westerly jets and relative minimums in the westerlies (or, alternatively, easterly jets). It wasn't clear to me what actually happens, but here's another way of looking at it: The anomaly wind field has u' and v'. If the anomaly consists of a wave train of symmetric cyclones and anticyclones, which are superimposed on some basic state, then the average u'v' is zero. But suppose the basic state is a westerly jet. The total state may then be a meandering westerly jet (with troughs and ridges). But, if the advection is stronger than differential Rossby wave propagation (?), the basic state will distort the anomalies; it tends to tilt the waves- the troughs and ridges tilt from SW to NE to the south of the jet and from the NW to the SE to the north. This tilt cause a nonzero average u'v', which is positive to the south and negative to the north, which means that eddy zonal momentum is being transported by eddy meridional momentum and the transport converges toward the jet, so that zonal momentum is being added to the jet. Whether this means the jet accelerates or the jet widens (or if the jet narrows?), I'm not clear. Notice that (if the jet is accelerating - I think it does, actually) this also increases cyclonic RV to the north and anticyclonic RV to the south of the jet; there is a relationship between eddy momentum convergence and eddy vorticity flux; there is also a relationship between EP flux convergence and eddy IPV flux (EP flux is a vector with vertical component determined by eddy temperature flux v'T' and meridional component determined by eddy momentum flux u'v'; increasing v'T' with height increases stability to the north; decreasing u'v' to the north is proportional to a northward flux of eddy cyclonic RV: v'RV'). There are mechanisms by which jets may sharpen themselves. (see links from http://www.atm.damtp.cam.ac.uk/people/mem/ ) Also, mixing of IPV or PV in general can/may lead to a 'PV staircase' because mixing between two contours of PV and mixing between two other contours of PV, in reducing the PV gradient in two regions, must then increase the gradient in between such regions. This has consequences for jets. A paper on this - "Multiple jets as PV staircases: the Phillips effect and the resilience of eddy-transport barriers" - is also linked from the above website. It is analogous (according to that paper) to mixing of potential density or temperature in a vertically stratified fluid - mixing can give rise to regions with even sharper density contrasts (I think it's called the Phillips effect). Perhaps not quite the same thing (because it's not multiple layers) but the mixing of the upper ocean, by cooling the surface and warming the bottom of the mixed layer, produces a thermocline - a sharper temperature gradient - at the base of the layer. The strong stratification in the thermocline makes it harder to mix additional water from below into the upper layer (it is also harder to vertically mix the air across an inversion, such as when the air near the surface cools at night - the vertical wind shear can cause mixing by way of a shear instability (Kelvin Helmholtz instability, I think) (which I think is analogous the barotropic instability in horizontal shear), but the stronger the stratification, the stronger the wind shear has to be before such mixing can commence (see also "Richardson number"); I only started reading that PV-staircase paper but I think it was a point of the PV-staircase concept that the sharpened PV gradients become an impediment to further horizontal mixing). In the lower atmosphere, mixing of the boundary layer (layer nearest the surface, unless one differentiates between that and a much thinner 'surface layer') can be driven both by kinetic energy input from wind shear-related instability, and by thermally-driven convection when heated from below (daytime over land, cold front passing over warm water); the thermally-driven convection also produces kinetic energy and the kinetic energy can be used to mix further upward into stable air above, which can produce a thicker boundary layer capped by a strongly stable layer such as an inversion, which resists further mixing. AND NOW FOR AN APPLICATION OF WAVE-MEAN INTERACTION: "Wave-maintained annular modes of climate variability" "HARTMANN Dennis L." "Abstract The leading modes of month-to-month variability in the Northern and Southern Hemispheres are examined by comparing a 100-yr run of the Geophysical Fluid Dynamics Laboratory GCM with the NCEP-NCAR reanalyses of observations. The model simulation is a control experiment in which the SSTs are fixed to the climatological annual cycle without any interannual variability. The leading modes contain a strong zonally symmetric or annular component that describes an expansion and contraction of the polar vortex as the midlatitude jet shifts equatorward and poleward. This fluctuation is strongest during the winter months. The structure and amplitude of the simulated modes are very similar to those derived from observations, indicating that these modes arise from the internal dynamics of the atmosphere. Dynamical diagnosis of both observations and model simulation indicates that variations in the zonally symmetric flow associated with the annular modes are forced by eddy fluxes in the free troposphere, while the Coriolis acceleration associated with the mean meridional circulation maintains the surface wind anomalies against friction High-frequency transients contribute most to the total eddy forcing in the Southern Hemisphere. In the Northern Hemisphere, stationary waves provide most of the eddy momentum fluxes, although highfrequency transients also make an important contribution. The behavior of the stationary waves can he partly explained with index of refraction arguments. When the tropospheric westerlies are displaced poleward, Rossby waves are refracted equatorward, inducing poleward momentum fluxes and reinforcing the high-latitude westerlies. Planetary Rossby wave refraction can also explain why the stratospheric polar vortex is stronger when the tropospheric westerlies are displaced poleward. When planetary wave activity is refracted equatorward, it is less likely to propagate into the stratosphere and disturb the polar vortex. " http://cat.inist.fr/?aModele=afficheN&cpsidt=962252 This is far from the only paper on the subject. I couldn't begin to get into all of it.
130700. Patrick 027 at 12:51 PM on 9 November 2008
        Arctic sea ice melt - natural or man-made?
        Another view - back to (x,y,p) coordinates: What happens when there is either horizontal variation in temperature advection, or in diabatic heating? Answered earlier (way way back in "Science and Society", I think): relative warming or cooling changes the vertical geostrophic wind shear, and the resulting ageostrophic wind leads to divergence and vertical circulation where the warmed region rises (and adiabatically cools), the cooled region sinks (and adiabatically warms). Now what happens when there is vorticity advection that varies with height? Suppose there is a gradient in AV in the horizontal, and the wind blows partly along the gradient. Suppose this varies with height, so that relative to the rest of the air in a column, there is some vertical level in which air with lower AV is being replaced with wind with higher AV. Setting aside variations in planetary vorticity for the moment, this would mean increasing RV at that level. If the old RV value was balanced with the mass distribution above and below, the new RV won't be - if it is more cyclonic, the resulting cyclonic ageostrophic wind is accelerated by the coriolis effect to the right, which means outward from the center (horizontally); there is divergence. This removes mass from the column, lowering the pressure at all levels. If the initial change in RV had been imposed equally at all levels, the divergence would, conserving angular momentum, reduce the RV while increasing the geostrophic RV until they match (and then there might be some osciallation about equilibrium if the perturbation were imposed relatively suddenly, radiating inertio-gravity waves ?). But when the initial RV change occurs at one level, the divergence at that level increases the geostrophic RV at all levels, and this causes convergence to occur at all the other levels. The mass-continuity requires then that there is vertical stretching both below the level of initial RV change (let's call that p1) and above it, while there is vertical compression occuring at p1. Thus the maximum upward motion is at the base of the layer at p1 and the maximum downward motion is just at the top of that layer. This has adiabatic temperature changes associated with it. If the air had neutral stability, the adiabatic temperature changes due to vertical motion wouldn't change the horizontal temperature gradients, but with some vertical static stability, the cooling and warming produce relative cold and warm areas just below and above p1, which are most intense closer to p1. This temperature field acts to change the pressure field away from p1, so that farther above and below, there is a greater change in pressure that is opposite to that due to the initial divergence at p1. Thus the effect of the divergence at p1 to induce convergence above and below p1 becomes concentrated closer to p1 in the vertical. This is how higher static stability reduces at least some aspects of the dynamic interaction across vertical distances. Anyway, the RV is reduced at p1 and increased below and above, with the greater changes closer to p1, until balance is approached between the wind and mass field. The result is a relative RV perturbation that is maximum at p1, decreasing below and above, with colder air just below p1 and warmer air just above p1, which suggests an enhanced stability at p1. Notice what this implies for the vertical IPV distribution. Such interaction occurs in growth of baroclinic waves by baroclinic instability. Note that the vertical extent of the wind field corresponds to a vertical extent of temperature advection by that wind, producing a temperature anomaly. --------- Bluestein has a simple explanation that suggests that an IPV wave train in an IPV gradient (a Rossby wave in IPV) which is confined either horizontally (to being along a basic state IPV contour) or vertically, will initiate Rossby waves like itself that propagate away from itself horizontally or vertically, from where it was confined; moreover, when these waves initially develope, they act to destroy the initial wave, so that the result is two groups of waves propagating away in either direction (with the group velocity). - see Bluestein, pp. 214-216. --- Baroclinic and barotropic instability (or at least one kind of it ?) can both be explained as counterpropaging Rossby waves in an IPV context. (see Bluestein pp.207-208, see also Martin). 1. Baroclinic instability: Imagine that higher in the air, IPV increases to the north, but below some level, the IPV increases to the south (in the basic state). In that case, Rossby waves phase speeds are in the opposite direction above and below; to the west above and to the east below. If the basic state temperature increases to the south, the basic state vertical wind shear is to the east (westerly) going up, which reduces the phase speed of each set of Rossby waves relative to the other. What else can happen is that the vertical penetration of the wind field associated with each set of Rossby waves allows the Rossby waves above to induce waves below and vice versa. Because of the reversal of basic state IPV gradient, the result can under some conditions lead to two sets of waves that amplify each other and in that also tend to keep each other from moving relative to each other. The basic state IPV gradient is generally to the north down to the surface (although I wonder if regional east-west components might reverse with height?); however, the temperature gradient implies that isentropic surfaces slope downward toward the equator, which means that for any two isentropic surfaces, there is a point to the south (in the Northern Hemisphere) beyond which there is no more air in between them; they are at the same pressure, and the static stability is positive and infinite. Convergence toward a surface high temperature region 'inflates' the space between a pair of isentropes, and at the point at which the air arrives, it has some vorticity; convergence will increase that vorticity while conserving angular momentum, with vertical stretching (the 'inflation' of the space between isentropes). In this sense (I think), a surface warm temperature anomaly, which is associated with either cyclonic RV decreasing with height or anticyclonic RV increasing with height, is 'induced' by a cyclonic IPV anomaly at the surface, and the basic state increasing temperature to the south (in the Northern Hemisphere) implies a basic state IPV gradient at the surface with increasing cyclonic IPV toward lower latitudes. Notice that, relative to the wind at some height, the wind around a warm region at the surface, with the basic state temperature gradient just mentioned, will tend to pull warm air from low latitudes east of itself while pulling cold air from high latitudes west of itself, and thus the temperature wave propagates to the east (at least as far as phase speed is concerned). One complexity: this is relative to the vorticity at some height above the surface (although perhaps even if the wind rotated anticyclonically above a warm surface anomaly, it wouldn't propagate as fast to the west as it would if the the thermal gradient were reversed?). What if there is a reversal in the horizontal IPV gradient in some horizontal direction? The result can be qualitatively similary; one could have sets of counterpropaging Rossby waves which are able to amplify each other: Barotropic instability. Notice a Rossby wave can't continue to propagate into a region without an IPV gradient (there may be some evanescent wave would could allow tunneling of a portion of the energy through such a region if finite in size). The group velocity might reflect? If there is a critical level where the wind is moving with the phase speed of a Rossby wave embedded somewhere else but whose wind field reaches the critical level, energy can be exchanged between the wave and the basic state at the critical level (you can imagine that there would be ongoing motion at the critical level that is not propagating relative to the air there. I'm not sure exactly how this works, though). Sharp changes in propagation at the tropopause (change in static stability, IPV and IPV gradient) and surface - reflection? refraction? etc. (I'm still learning.) And so on. (I'm just about done with this here.)

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