Skip to main content

View Diary: Earth (Day) Science: Climate and the energy budget (42 comments)

Comment Preferences

  •  Thanks Again, Yes (0+ / 0-)

    it did help quite a bit.

    Some additional comments, again because I would like to know more.

    Your graph indicating temps from natural and anthropogenic causes, and the observed, raises a question.  How can one distinguish between natural and anthropogenic causes and its affect on temps?  I do understand what are anthropogenic causes (changes in landscape from forest to farmland, cities or housing, fuel emissions, factory emissions, etc.), but how does one account for the temp difference seen in the climate, or the local temp due to these specific changes?  Small point, but one I wanted to understand better.  I've read and understood the absorption argument on landscape change, and I read and understood the amount of CO2 emissions man contributes compared to nature, but I have never read what affects those have on temps in a statistical or numeric manner.

    Your comment:

    In place of GCMs they argue by correlation. This makes no sense. You cannot simply show solar sunspot number and say "Such changes in irradiance could, if large enough, drive significant climatic change and the climatic record" without quantifying the effect of the change in insolation on temperature. You cannot simply plot length of solar magnetic cycles with suitably scaled Northern Hemisphere temperature records without quantifying a causal mechanism.

    It seems to me that the same argument is currently used with CO2 to great affect.  CO2 goes up, and so does the temp, except when it doesn't, but CO2 is still considered the driver.  Then one looks at the ice core data and we find that it lags temp by 800 or so years.  So how is it a driver?  When sun spots are observed (and I believe they have been observed for several hundred years) and then comparisons are made to temp, there is a direct correlation with temperature change - increased sun spot activity leads to increased temps and a decrease in sun spot activity leads to a decrease in temps.  I understand, only from ignorance (ironically), that there is not a quantifiable change in temp with sun spots.  I take that to mean "there will be a 0.5C temp change over the next ten years because there were 26 fewer sun spots last year", and I do not know that, nor have I read that anywhere.  It simply seems more logical to me that the sun would have a much greater impact on temps than CO2, for whatever reason, although there are many - source of all energy, protection from cosmic rays, cloud formation, etc.

    We would not have seen cooling in the recent past because solar activity over that time period was higher (your 25-30 year window).
    Actually this is incorrect. We have excellent solar records at the top of the atmosphere over that timespan, and we've seen a slight decrease since about 1980. Not as strong as the increase over the first 50 years of the previous century, but still noticeable.

    What I meant by this was, we had roughly 30 years of increased solar activity and roughly 30 years of increased temps.  Then, we had about 8 years of reduced solar activity and about 8 years of cooling or stagnant temps.  That is why I believe that the solar variance more directly reflects the changes in temps we have seen.  I don't recall the anti-correlation, though I might have heard about it before.  If there is a more current graph on this, please point the way.

    Thank you for the very clear explanation about the water.  A question, though:  is the difference, then, between a feedback mechanism and a forcing mechanism the length of time it is in the system?  I ask this because it seems like CO2 behaves in a similar fashion as wv (more of it, retains more heat, generates more of it - or positive feedback), it's just that it happens on a longer time scale.

    •  Need to quantify your mechanisms (0+ / 0-)

      Your graph indicating temps from natural and anthropogenic causes, and the observed, raises a question.  How can one distinguish between natural and anthropogenic causes and its affect on temps?

      It's a model result. You know what the model expects for a system with preindustrial CO2 levels and land use, so all of the changes are driven by solar insolation, volcanic aerosol, etc. That's the natural term. Add to that known anthropogenic changes in GHG, aerosol, ozone, land use, etc and you get the sum of natural + anthropogenic.

      Please understand that the model is mechanism driven. There is a lot of covariance analysis out there to try to figure out which mechanisms are most important (in this case it's GHGs) but when you're actually making predictions you need to quantify those mechanisms. That is, you need to answer: for X change in A, what is the magnitude of change in B? Not, A is changing, so is B, ergo one must drive the other. Eg, we know the IR absorption of CO2, we know how much there is in the atmosphere, so we can quantify the heating driven by CO2 absorption. There are many feedbacks and second order effects, so it's not quite that easy, but that's the approach you have to take, not correlation.

      How good is the model? Well, there is exactly one test: experimental validation. So far it is working pretty well over the observed range of GHGs, insolation, aerosol, ice cover, etc. It misses a lot of fine structure, and it systematically underpredicts, but it gets the general trend right.

      That is not proof that our understanding is essentially correct, but science doesn't do proofs. We have been unable to identify anything else changing in the right direction, of the right magnitude, on the right timescale, that could explain the trend besides GHGs. We have been able to identify one possibility that does -- GHGs. Maybe something else is indeed controlling the show, and we just don't know about it. But we have no reason to believe that.

      Then one looks at the ice core data and we find that it lags temp by 800 or so years.  So how is it a driver?

      In this case it isn't. This is exhibit A in conflating causation and correlation. We know that increasing CO2 without directly affecting T will trap more outgoing IR so T will rise. What if we increase T without directly affecting CO2? That's what we see in the ice cores, as orbital variations take us out of an ice age. Greater insolation will lead to greater ice melt. That turns some areas that were once covered in ice into first a wetland. You now get respiration which releases CO2. As it continues to warm, the wetland dries up (eg, most of Wisconsin, once covered in ice, is not a swamp but prairie and forest), so we get increased respiration, from less efficient anaerobic methanogenesis to aerobic respiration. A fraction of the organic matter once buried under ice turns into CO2, so CO2 rises. As CO2 rises, it increases temperature by IR absorption, which increases CO2 etc etc until orbital variability turns the system around into another ice age. This is an example of a positive feedback, and in this case CO2 is a feedback amplifier, not the direct forcing (orbital variability is the forcing).

      Note that it doesn't matter which one starts first, T or CO2, they amplify each other -- that's the nature of a positive feedback. But just because one is the forcing at some times in the past doesn't mean it always is. The climatic changes leading to the Permian extinction were almost certainly driven by CO2 emissions from the Siberian Traps. But that drove a T increase, which accelerated not only CO2 but methane increases. There are examples in Earth's history in which T changed first, and examples in which CO2 changed first. But the result was the same -- further increases in both T and CO2.

      Today the orbital and solar output terms are tending to drive temperatures down, CO2 is tending to drive it up. Which wins depends on relative magnitude.

      What I meant by this was, we had roughly 30 years of increased solar activity and roughly 30 years of increased temps.  Then, we had about 8 years of reduced solar activity and about 8 years of cooling or stagnant temps.

      Where are you getting your insolation data? Over the last 120 years, we've had 80 years of increased solar output, until about 1970, 10 years where the trend leveled off, to about 1980, and 30 years of decrease (see figures above). There is also an 11 year sunspot cycle overlying the longer trend. The last 30 years have the highest quality data, since those are taken above the atmosphere (the others are from ground observations). The last 30 years have also seen the strongest warming. Even so, you cannot say that the warming of the first 80 years was driven by solar output (or, for that matter, CO2 or anything else) -- you need to quantify your mechanisms (current estimates are that solar increases contributed about half the warming term up to ~1960 with the balance in GHGs and volcanic effects. Since then the GHG term has taken off). Correlation != causation.

      A question, though:  is the difference, then, between a feedback mechanism and a forcing mechanism the length of time it is in the system?

      Relative timescale is key. If the timescale of the mechanism is very short compared to the timescale of the change, it can only act as a feedback. Of course, if the mechanism is external to the change, there can be no feedback (as far as we know, global climate change has no effect on Milankovitch cycles, eg). CO2 has a multitude of timescales, ranging from the very short (marine biota) to the very long (geological processes) so it's more complex than something like water vapor and can act as both forcing and feedback.

      •  Keep it coming (0+ / 0-)

        I sincerely appreciate the time you have taken to respond to my series of questions.  You have given me several new bits of information and new ways of looking at the old information I thought I understood.  So thanks.

        Still a couple of questions:

        I understand the best way to test models is through experimental validation, or testing its predictions and then observing what actually happens.  Additionally, though, isn't it useful to test the model on the past and see if it can replicate past climate?  From what I have read, no model can accurately predict the past  for extended periods of time, which leads to the argument that if the model cannot accurately model the past, how can it accurately model the future?  But now I understand the point that I had not thought of earlier, which is how CO2 can at one point in time be an amplifier and at another time be a driver, which would make the model more complicated.  But I'm sure modellers have overcome that one...

        I am curious as to how you can say that nothing besides GHG can explain warming because of my earlier graph of solar activity.  I would say GHG's do play a role, but, especially in the 20th century, solar variance much more accurately followed temp changes than did CO2 concentrations.  

        I am really harping on the idea that CO2 is a main driver simply because of all the hype surrounding it and the policies being enacted to control it.  If man generates less than 3% of all CO2 generation and CO2 makes up a fraction of a percent of all GHG's in the atmosphere, I personally believe we should be looking elsewhere for a serious driver.  Or even still, if it is a driver, then learn to adapt to changing conditions as, based on that paragraph you wrote in the last response about changing from ice to a swamp, more plants, more CO2, etc., then we can't really stop it anyway.  Enough said there for the moment.

        In response to your question, I do not have "insolation" information.  I am guessing you are referring to my information on solar activity and temp scales or graphs, which I posted earlier.  Other than that, I read quite a bit, but not for the purposes of publication, simply information.  I have read, though, that the solar variation link does not accurately reflect temp variation from the 1990's.  However, since 2000, temps have flattened or dropped overall.  Somewhere along the way, I have read the argument that it takes a great deal of time to change the temp of the oceans, either up or down, which is logical.  This carries a kind of momentum, so to say, in that if temps are rising, it should take some time to slow and reverse, as the ocean is a tremendous heat sink or source and thus causes the atmospheric temps to change slowly.  Same if temps dropped.  There should be some kind of time lag.  Additionally, with all the other variables changing, specifically CO2 which is a positive feedback mechanism or driver, which would help continue to drive the temps in the current direction, even with the ocean exerting its influence.  That was the argument as I understood it.

        I have not researched more recent solar variance information as I do not have general access to research sites.  When I have time, I look.  Most of my information comes from websites that post some research papers, or books both supporting and refuting anthropogenic global warming.

        Again I would appreciate any recommendations for personal research in this area - books, websites, articles.

        Thank you again for your detailed responses.

        •  Hmm, tried to reply but didn't take (0+ / 0-)

          Additionally, though, isn't it useful to test the model on the past and see if it can replicate past climate?  From what I have read, no model can accurately predict the past  for extended periods of time, which leads to the argument that if the model cannot accurately model the past, how can it accurately model the future?

          Hard to tell how well models work if you go back very far -- the uncertainties in temperature reconstruction also get very large. However, models are "spun up", that is, the output has to match the past (how far back depends on the question being asked) before it can project into the future, and if the model cannot replicate at least the recent past you have to go in and fix it.

          The further back you go the more dependent you are on proxies. Even as recently as 100 yrs ago you have to watch sample bias (lots of data in Europe and US, not so much from elsewhere). Data quality of the last 4-5 decades is excellent, however (in part because of Cold War issues).

          I am curious as to how you can say that nothing besides GHG can explain warming because of my earlier graph of solar activity.

          That link does not show solar insolation, and certainly shows no data since 2000, since that paper dates back to 1999. Soon and Baliunas do show variability they claim arises from solar activity overlying an increasing trend they attribute to GHG emissions (Fig 4).

          If man generates less than 3% of all CO2 generation and CO2 makes up a fraction of a percent of all GHG's in the atmosphere

          Current anthropogenic carbon flux to the atmosphere is ~8 Gtons C/yr (you might be interested in an earlier diary) This is small compared to the ocean outgassing flux of ~90 Gt/yr and the 60 Gt/yr from forests (and similar amount from soils). But take away the ocean uptake flux is also ~90 Gt/yr; the terrestrial biosphere uptake flux is ~120 Gt/yr. IOW, the anthropogenic gross flux is quite small compared to the natural terms, but it is the entirety of the net flux. How do we know this? Because before the industrial revolution CO2 levels were bouncing around in a narrow range about 280 ppm. If the atmospheric carbon reservoir is ~constant in size, the input and output fluxes have to match.

          CO2 is second only to water vapor in GHG abundance, and we've already talked about water vapor.

          Or even still, if it is a driver, then learn to adapt to changing conditions as, based on that paragraph you wrote in the last response about changing from ice to a swamp, more plants, more CO2, etc., then we can't really stop it anyway.

          Probably we can't, but I have yet to hear a rationale how adaptation would be easier and cheaper in the absence of mitigation. We do have a couple of natural tendencies working for us right now, however: orbital variability would put us into an ice age (although that operates on a 104 - 105 yr timescale its effect on a 10-100 yr timescale is extremely small), and solar activity is currently in a low output mode. But we have no idea how long it will stay that way, and insolation from the sunspot cycle is scheduled to increase in about 2 years. Anyway, starting early is easier than starting late.

          This carries a kind of momentum, so to say, in that if temps are rising, it should take some time to slow and reverse, as the ocean is a tremendous heat sink or source and thus causes the atmospheric temps to change slowly.

          The atmosphere responds very quickly, land surfaces more slowly, oceans even more slowly, ice cover highly nonlinear. If you're going to argue momentum you need to quantify the amounts. The best way we have to do this is by models, which show there is a significant amount of warming "locked in" the system even if we were to cap GHG emissions today. (This has corroboration from the ice core record, in that the CO2 trend wrt temperature is far from equilibrium, according to past history. But as they say on the prospectus: Past history is no indicator of future performance)

          Again I would appreciate any recommendations for personal research in this area - books, websites, articles.

          The best one is the IPCC's 4th Assessment Report. You can download the Technical Summary (30 pp or so, IIRC) or the full report (>1000 pp). It has already been shown to be conservative (they do a poor job with ice) so keep that in mind. Still, it's quite comprehensive, lays out everything, so if you have issues with it you can at least pinpoint where those are and go to the literature.

          Occasionally other agencies do similar reports: the Pentagon's scenario from a few years ago had some seriously scary hair-on-fire stuff, but maybe that's their job -- here's coverage on it. That was a low probability(?)/extreme impact scenario Taleb might call a Black Swan -- or Grey Swan, since it's not quite unforeseen, but those are frequently the events that change everything.

          UCAR also has an intro online, but it's not very quantitative.

          •  Again thanks, (0+ / 0-)

            I thought you might have given up.

            I'll tackle this in the order presented above:

            I understand the modelling and errors getting bigger the further you go into the past.  Chaos theory in action, in a way.  However, you made one statement that concerns me in that you wrote that the recent data is very accurate.  I recently read a report on the temp measuring stations in the US and found that the data is extremely unreliable and that the errors in temp explains temp increases seen simply in the margin of error.  It was an enlightening report in that I had heard rumors and pictures of these claims many times.  However, this report was hard data with pics on many of the stations.  The guy had a website at www.surfacestations.org, but I didn't look for the report there.  With garbage data from land readings, how does one compensate for that?  Or should we hold off action until we get more reliable data? Or how does one correct for the errors?

            I believe I understand the net flux of CO2 you wrote about.  However, the industrial revolution coincided unfortunately with the end of the little ice age.  For arguments sake, if the temp happened to increase on its own, would that not change the equilibrium?  Then there would be a net change in CO2 in the atmosphere simply due to the re-establishment of equilibrium where the atm CO2 is higher than it was earlier.  How would it then be possible to determine what flux amount was due to man and what was due to nature?

            Along the same idea as the equilibrium argument you present, the manmade CO2 does not all go into the atm and stay there indefinitely.  Nature takes up some in order to reach a new equilibrium.  I do not know the lag time for that to occur, but I'm hoping you might as that would be a large factor in modelling I am sure.  But continuing, if man emitted enough CO2 to double the CO2 concentration in the atm, then the oceans would necessarily have to take up a very significant amount of CO2 in the air in order to establish a new equilibrium.  Thus, man would need to emit a lot more CO2 than just enough to double all that in the atm today.  Obviously, man had been freely emitting CO2 into the atm for over 100 years and we have yet to double it yet.  Thus, it would take a hell of a long time to do that.

            My point here is that man's changes are small and would change the equilibrium by a very small amount by itself (man's contributions) when compared with what nature could do on its own.

            Actually, I have heard many, many ideas on how adaptation is not only cheaper, but much more beneficial.  We have an idea, low ball estimates though, on what the costs of lowering CO2 emissions would be - trillions and trillions of dollars to world wide economies, less reliable energy, less energy, more expensive energy, longer times for third world countries to come out of poverty, etc.  Adaptation has more benefits than simply improving our ability to survive in a warmer climate.  Keeping energy costs low and allowing all nations to develop fossil fuel sources that they have would speed up economic development rather than hinder it.  Economic development has led more people out of poverty than anything else in human history.  With an improved economy, nations can more easily protect their environment at a lower cost, percentage wise, than if they had remained poor.  I don't know what exactly you would need to see in order to realize adaptation is easier, less costly, and makes more sense than trying to strangle our world economy in order to reduce one GHG in the hopes of lowering temps 0.7C in 100 years, if we're likely.  Adaptation has much more measurable positive results.

            I don't have information on specific temp changes wrt the momentum I mentioned earlier.  It is simply an idea that I read about and seemed logical in that the ocean is an extremely large heat sink wrt earth and largely controls the weather and hence the climate.  Yes, atm temp changes quickly, but much less so when near large bodies of water than when far away from water.  WRT momentum, I simply was stating or implying that when water is warm, it takes a very long time to cool a very large body of water.  With that in mind, and the idea that atm temps do heavily depend on water temp, it would take a long time to change temps in the atm for that reason.  All those things are relative, obviously, and no I have no quantitative data to support that at this time.  There was the slow down in the Atlantic current (forgot the name at the moment) that supposedly helped create or exaggerate the little ice age that is an example of my argument.

            Thank you for the rec's.  I have read much of the IPCC, including the latest info.  However, I have also read a lot from scientists who used to be writers for the IPCC and even the head guy for the IPCC and they often look at the IPCC as having a very strong political agenda, and a very weak desire to be scientifically accurate.  Thus I am skeptical of their publishings.  I look at research papers or articles from scientific publications that are more or less free, or occaisionally pick up a Sci American or Science mag, or the occaisional book.

            Thanks again for the very insightful information.

            •  several points (0+ / 0-)

              I recently read a report on the temp measuring stations in the US and found that the data is extremely unreliable and that the errors in temp explains temp increases seen simply in the margin of error.

              Temperature measurements are among the easiest to do and precision is quite good. There were issues with sampling bias (urban heat effect) and satellite calibration about 15-20 years ago that did require correction. This was dragged up again in more recent years, but those criticisms are out of date.

              the manmade CO2 does not all go into the atm and stay there indefinitely.  Nature takes up some in order to reach a new equilibrium.  I do not know the lag time for that to occur, but I'm hoping you might as that would be a large factor in modelling I am sure.

              Works on multiple timescales, from the very short to the very long. If you look at the carbon cycle figure in the diary linked above you will note that uptake fluxes for both oceans and terrestrial biosphere > outgassing fluxes, indicating that those reservoirs are not at equilibrium. They account for roughly half of the net fossil fuel/land use flux, the remainder is in the atmosphere. It's all about relative rates.

              Obviously, man had been freely emitting CO2 into the atm for over 100 years and we have yet to double it yet.

              A 40% increase in 150 years is dramatically fast, on the timescales of natural processes. Again, it's all about relative rates.

              Actually, I have heard many, many ideas on how adaptation is not only cheaper, but much more beneficial....Economic development has led more people out of poverty than anything else in human history.

              I would certainly appreciate references on those ideas. Extreme poverty is certainly at least as destructive as extreme affluence. And I am no economist. Yet those economists who work to help developing countries -- the most prominent names are Jeffrey Sachs and Joseph Stiglitz -- certainly do not agree that adaptation in the absence of mitigation is workable.

              I don't know what exactly you would need to see in order to realize adaptation is easier, less costly, and makes more sense than trying to strangle our world economy in order to reduce one GHG in the hopes of lowering temps 0.7C in 100 years, if we're likely.

              Do you have a quantitative basis for this statement? There are a number of studies out there that show otherwise, such as the Stern Review and the McKinsey Report. You may not agree with some or all of their assumptions or conclusions, but they do lay those out clearly and thus provide a basis for discussion. Perhaps you could do a diary on one of them.

              There are also a number of major industrial companies, including energy, transportation, and heavy industry, who would not agree with you either, such as Shell Oil, Volkswagen, Rolls Royce, Repsol (oil company), GE, DuPont, Johnson and Johnson, Shanghai Electric, Statoil, and others.

              However, I have also read a lot from scientists who used to be writers for the IPCC and even the head guy for the IPCC and they often look at the IPCC as having a very strong political agenda, and a very weak desire to be scientifically accurate.

              Normally I stick to what is quantitative, but understand that a statement like this without independent evidence amounts to an ad hominem criticism. It is true that this time around (AR4) the scientists were pushing for stronger statements than the economists or policy experts of the IPCC. But it wasn't because of a "political agenda".

              In the end however, irrespective of any political agenda the scientists or their critics may or may not have, there is exactly one test the scientists have to pass, and that is experimental validation.

              We've been modeling climate for at least 3 decades, with significant improvements over time. 30 years is not terribly long in terms of natural timescales but it is long enough to tell us whether we're completely off. If you look at the initial projections from the early Assessment Reports you will note that we're doing pretty well. Actually we've been a little on the low side since 1992.

              •  Sorry about the wait, (0+ / 0-)

                been very busy.  In response:

                You wrote:  Temperature measurements are among the easiest to do and precision is quite good. There were issues with sampling bias (urban heat effect) and satellite calibration about 15-20 years ago that did require correction. This was dragged up again in more recent years, but those criticisms are out of date.

                I don't see how they can be "out of date" when the report I mentioned was completed in 2009, which you can read here: http://www.heartland.org/...

                The criticisms are definitely not out of date, nor have the issues been addressed or the problems of bad temp stations been corrected.  This is a severe issue and goes to the heart of the "global warming" argument - is there actually warming going on?  Most scientists consider the data collected in the US as the most accurate and reliable, yet this report absolutely refutes that assumption.  Can you point me to information that says the temp measuring issues identified in this report has been corrected in any meaningful way?  If the raw data in the most reliable region is inaccurate or questionable, what does that say about the rest of the world's data set?  Satellite data only goes back a couple of decades, and that does not a climate record make.

                I'll have to look at the link you included again to review relative rates and establishing new equilibriums.

                The costs of implementing Kyoto-like changes to our economy are everywhere, so I doubt I need to provide you that information.  The costs of adapting to a warmer climate, or a changing climate, is dramatically less based on the common sense that that is what mankind has been doing since his arrival.  If we don't have enough land where we are, we make more (Japan, Netherlands) or build walls to hold water out.  If it rains too much, we build bigger canals.  The list is endless in how we adapt to a changing environment.  Cutting energy use makes us weaker and less able to adapt.  Increasing energy supplies makes us stronger and helps us to adapt much more easily than without it.  For arguments, see DVD Evangelicals & Global Warming.  It is a debate at a religious college, but it is all science.  One of the three areas covered was the costs of either adopting Kyoto as written or adapting.  It was quite informative.  

                The costs of adapting as opposed to cutting energy are also highly exaggerated when the absolute extremes in Al Gore's movie are taken as true.  When actual consequences predicted by  even the IPCC are used, adaptation to the changes is nearly nothing.  There has been no sea level rise on islands in the Pacific, no increased hurricane activity, no increase in severity of storms, basically zippo Inconvenient Facts that foretell the coming doom portrayed.  Thus, there is no cost to date to adapt and huge cost to give up our cheap fossil fuel energy supplies.

                I was thinking of a diary, but I haven't tried it yet.  I will check out the links you provided and provide other cost/benefit analyses as needed.

                Major energy companies that do not agree that adaptation is better than not using fossil fuels?  I will have to check the link on that one, but on face value, it is political or simply jumping on the bandwagon so one does not look bad.  Shell recently gave up on its alternative energy development because of costs.  Without government aid, nothing but fossil fuels would be used based purely on economics.  Ok, hydro and geothermal are cheap as well.

                I don't believe that repeating what a lead author of the IPCC writes is an ad hominem criticism.  It is stating facts as presented.  The author described the process of creating the IPCC reports on global warming in extreme detail.  As he was lead author in 2001, he would know.  He quit specifically because it was politicized, the process that is.  Scientific opinions were discarded when they could not support the summary that was written prior to the scientific evidence being reviewed.  If the summaries were written for the politicians and these summaries were not in following with the scientific evidence, then what agenda were they following if not a political one?

                Experimental validation is correct as being the only evidence that supports or refutes a theory.  As the evidence sits now, there is nothing out there that proves anthropogenic global warming.  There is also nothing out there that proves man does not cause global warming.  What is out there simply supports the common sense notion that climate changes.  Since 1998, the data basically says there has been no statistical warming, and there may have even been cooling.

                I've reviewed the IPCC modelling info through their history.  The range is very large overall.  I am not sure how to quantify error in all the modelling projections, and that would be good info to have.  But based on memory, accuracy is not all that important for this, but when modelling gives a range of temp change from 0.5 to 3C over 100 years, that seems rather an extreme range.  Given that our measuring techniques are not that great (see report above) maybe that is good considering we can't measure that well now, I don't know.  In the end, I don't agree with asking the world to do without unless it can be proven beyond a reasonable doubt that doing without will bring about a reasonable change to our collective benefit.  I see all pain and no gain.

                Thanks again for the info.  I'll write more after reviewing the above links.

                •  Another interesting bit of info (0+ / 0-)

                  Here is an article I found that again points out the inaccuracies of surface temps and the misinterpretation of the data it does collect:

                  http://money.cnn.com/...

                  It also mentions, as do many other similar articles, that, for the cost demanded, there is little to no benefit of imposing all these CO2 restrictions on the US.

                  Thought you would be interested.

Subscribe or Donate to support Daily Kos.

Click here for the mobile view of the site