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Water Vapor Causing Climate Warming 434

karvind writes "According to BBC, new studies suggest that water vapor rather than carbon dioxide in the atmosphere is the main reason why Europe's climate is warming. The scientists say that rising temperatures caused by greenhouse gases are increasing humidity, which in turn amplifies the temperature rise. This is potentially a positive feedback mechanism which could increase the impact of greenhouse gases such as CO2. Even though 2005 will probably be warmest year, climatologists still differ in opinion"
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Water Vapor Causing Climate Warming

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  • by SirDrinksAlot ( 226001 ) on Sunday November 13, 2005 @01:34AM (#14018924) Journal
    Too bad we wont be able to say "At least it's a dry heat" if this continues.
  • Um... duh? (Score:4, Insightful)

    by drhamad ( 868567 ) on Sunday November 13, 2005 @01:35AM (#14018926)
    I could be missing something, but isn't this basic astronomy (or whatever science you care to term it)? Water vapor (among other gasses) is responsible for keeping a planet heated, and not a frozen ball of rock like Mars. Maintaining that delicate balance of how much water is in the air is important of course, but noting that water is causing the atmosphere to retain heat is... nothing new.
    • Re:Um... duh? (Score:4, Informative)

      by Coryoth ( 254751 ) on Sunday November 13, 2005 @01:53AM (#14018971) Homepage Journal
      I could be missing something, but isn't this basic astronomy (or whatever science you care to term it)? Water vapor (among other gasses) is responsible for keeping a planet heated, and not a frozen ball of rock like Mars. Maintaining that delicate balance of how much water is in the air is important of course, but noting that water is causing the atmosphere to retain heat is... nothing new.

      Yes, this is not some groundbreaking new assertion. In fact it is things like this - feedback mechanisms (both positive and negative) that make climate change modelling so hard. If it was a simple matter of "C02 creates more warmth" we'd have figured it all out a while ago. More warmth can produce more water vapor, but depending on what type of clouds are formed you can end up with trapped heat, or more solar radiation reflected and a cooling effect. There are many other feedback mechanisms that I simply can't recall and many more I've never heard of. How and when they respond, and how they interact makes for a very difficult and complex problem indeed.

      Jedidiah,
  • by drgonzo59 ( 747139 ) on Sunday November 13, 2005 @01:36AM (#14018929)
    Scientists promptly advised everyone to:
    1. Stop drinking water
    2. Stop breathing
    3. Stop taking showers (note: this doesn't apply to some countries such as France and Mexico)
    • On a serious note, there's currently no valid suggestions as to what we can do about global warming. People are still arguing about whether or not it exists instead of thinking about what we can actually do about it. So far a grand total of one proposal [thespacereview.com] has been made as to what we can do about global warming. It involves building spacecraft to hover at a stable point between the sun and the earth to divert sunlight off into space. Sound crazy? Ok, what the hell else can we do? Regress to living in the
      • Re: (Score:3, Funny)

        Comment removed based on user account deletion
      • Weel, trying to cut down on CO2 production is always a good idea, even if it's just to be able to enjoy our fossil fuels longer.
        • Problem is though, while it was C02 and greenhouse gases (is C02 a greenhouse gas?) that began the rise in temperature, other factors (such as water vapour) are going to continue to rise it. Lessening greenhouse gas emissions would help to lessen the acceleration of the temperature, but the temperature will continue to rise regardless. We'd have to scrub the C02 back to levels lower then what they started out to be, before we began emitting greenhouse gases at ridiculous levels.

          But don't expect the Australi
          • I think the water vapour is an unwanted, ubforeseen side effect of global warming. CO2 is a greenhouse gas and helps raising the temperature of the atmosphere. Because of the increased temperature, more water evaporates and the water stays in the atmosphere longer. This helps increasing the temperature of the atmosphere even more...

            I once attended a talk about the greenhouse effect, and this guy told us that even if we stop emitting CO2 totally from now on, the temperature of the atmosphere will still rise
      • The problem with the issue of glboal warming has become more of a political and even moral issue. It is not any more about scientific research, it became something of a liberal vs. conservative or democrat vs. republican issue. At this point forget about any objective data and solution, it is like finding objective oppinions in the abortion debate. Every scientist already made their mind about the existance/or non-existance of global warming or some about a method to fix it if it exists (tax the oil compani
        • You're right that it's a political issue. The limits to growth people have latched onto global warming as an excellent reason for us to regress. What I fail to understand is how self respecting scientists can actually think that stopping CO2 production (or any passive solution) will halt global warming. If global warming really is a problem we need to actively reverse the process. If industrial activity is to blame for global warming, no amount of reduced industrial activity will put the genie back in t
        • I think yours is the exact reaction oil companies and republicans are hoping for. Buy simply buying enough research to instill confusion in the public they can keep their profits up and prevent stricter regulations on emissions.

          As for me I always look at the car. If a guy is drving a fice year old honda or a subaru (or even biking) he is more likely to tell me the truth then if he is driving a brand new BMW or a Mercedes.

          Yes I know both BMW and Mercedes make junky cheap cars too now but you get the idea. Ta
      • > On a serious note, there's currently no valid suggestions as to what we can do about global
        > warming. People are still arguing about whether or not it exists

        Okay, let's suppose, hypothetically, for the sake of argument, that it does exist, and then we can get on to arguing about whether we *should* do anything about it. We'll have to settle that before there's much point in discussing *specific* actions...

        I mean, *why* should we try to stop global warming? We know from paleontology that the earth
    • And stop pissing into the wind! Though that seems to be the current global climate strategy.
    • France will already be contributing enough steam once they put out all those fires...

    • reduce CO2 emissions. It's the CO2 emissions that start the process; water vapor serves as an amplifier and positive feedback.
  • by evw ( 172810 ) on Sunday November 13, 2005 @01:37AM (#14018930)
    Warming starts with CO2 and other greenhouse gases. Warmer climate means more evaporated water in the atmosphere. Guess what? Water vapor is also a greenhouse gas. So climate gets warmer. Lather. Rinse. Repeat.

    This isn't a story that undermines or changes the prevailing scientific view. This may allow some fine tuning of the models. Some skeptics had argued with the results of the models because they didn't believe the contribution of water vapor. This may force them to reevaluate their view. (Yeah right).
    • Warming starts with CO2 and other greenhouse gases.

      Twice as much water is produced in typical hydrocarbon reactions than CO2
      C(N)H(2N+2)+[(3N+1)/2]O2-->(N)CO2+(N+1)H2O
    • by account_deleted ( 4530225 ) on Sunday November 13, 2005 @02:00AM (#14018998)
      Comment removed based on user account deletion
    • by woolio ( 927141 ) * on Sunday November 13, 2005 @02:00AM (#14019000) Journal
      Dihydrogen Monoxide has been found in *every* cancerous cell, has been attributed to thousands of deaths per year, and is now also causing global warming. Obviously this harmful substance must be eraticated!
    • by Mateorabi ( 108522 ) on Sunday November 13, 2005 @02:51AM (#14019141) Homepage
      The parent got it almost right. evw seems to imply a runaway chain reaction, even though there is a stable equilibrium. When a true atmospheric forcing agent causes the temperature to rise more water vapor is released, amplifying the effect. But there is a finite limit, even if it is >100% amplification. In fact, H20 accounts for 1/3 to 2/3 of the greenhouse effect (compare with 10-25% for CO2.)

      But this vapor is just a feedback effect, not an atmospheric forcing. This is due to the incredibly short residence time of water in the atmosphere of ~10 days. This means that even if you could somehow instantly cause the earth to have 0% humidity everywhere, things would stabalize back to "normal" within about 20-30. True forcings like CO2 have residence time of decades, which makes them the greenhouse gas to worry about.

      Everyone posting here should first read this article [realclimate.org] for the full explination. The site in general is excelent.

  • by pHatidic ( 163975 ) on Sunday November 13, 2005 @01:43AM (#14018941)
    The reason we don't know how much global temperatures are going to rise is because we don't know enough about water vapor. Water vapor is thousands of times more potent than man made greenhouse gas. The main reason we can't 100% accurately predict the temperature is because we don't know for sure where the water vapor goes in the atmosphere. However, that does not mean that water vapor is causing global warming. Human emissions are the reason why there is more water vapor in the air than ever before. This isn't really knew, mainstream science has known this for ten plus years.

    Accepted facts about global warming are as follows:
    a)We are putting more greenhouse gases into the air than ever before.
    b)Greenhouse gases trap heat.
    c)The earth is getting warmer.

    No one disagrees on these facts. The only legitamite disagreement is on how much warmer the earth will get, and this is because we don't know where the water vapor sits in the atmosphere. Supercomputers estimate the temperature increase will be between 1.5 and 11 degrees celcius in the next 50 years. At the low end we are seriously screwed. At the high end it is the end of civilization as we know it.
  • I knew I should've voted for the EPA to ban that blasted dihydrogen monoxide!
  • Here's the Deal (Score:5, Insightful)

    by mouse_clicker ( 760426 ) on Sunday November 13, 2005 @01:58AM (#14018995)
    (Hopefully) before this ends up in a big pissing match over whether or not global warming is real, I'd like to lay down some ideas.

    Our climate changes- it has for billions of years and it will for billions of more years.

    Our climate is *incredibly* complex, so accurate prediction either way is nigh impossible (and I think it's arrogant to imply we know enough about our climate to even try to control it).

    Global warming *is* happening, but factually only in the sense that our planet has been getting warmer- the debate is over whether or not man is to blame. Keep in mind, we just came out of an ice age several thousand years ago, so global warming is basically a given until we enter the next ice age.

    There is NO consensus on whether or not man-made global warming is happening- anyone who claims to have "climatologist" friends who say it most definitely is or isn't real and that all the real scientists agree are just pulling stuff out of their ass (and it's pretty obvious, too, so don't even try to do it).

    Not everyone who believes global warming is caused by man is a crazy hippy and not everyone who believes it isn't caused by man is some money-grubbing republican. It's that kind of black and white approach to this and other topics, both by the people and especially the media, that has trivialized the issue at hand.

    Please try to keep this in mind.

    -Moses
    • Re:Here's the Deal (Score:2, Insightful)

      by Anonymous Coward
      There is NO consensus on whether or not man-made global warming is happening

      Actually, there is a consensus, among scientists.

      The debate over global warming has essentially been one with scientists on one side, and ideological conservatives and their paid pressure groups on the other. This is neatly demonstrated by the way in which people trying to brush off the scientific evidence invariably do so not by responding to the scientific evidence in a scientific way, but by relying on non-scientific, philosophic
    • Re:Here's the Deal (Score:5, Interesting)

      by Coryoth ( 254751 ) on Sunday November 13, 2005 @02:42AM (#14019118) Homepage Journal
      It's that kind of black and white approach to this and other topics, both by the people and especially the media, that has trivialized the issue at hand.

      it's always useful to apply Fisher's deduction:

      "The more issues a person attempts to shoehorn down into an artificial liberal/conservative dichotomy, the more certain you can be that the person is an American."

      Debate about climate change is a debate in the US because the whole issue is deconstructed and soundbitten into a pair of simplistic politicised extremes with nary a scrap serious reasoning left. If you actually read the IPCC reports, and the peer reviewed criticisms (as opposed to the op-ed pieces) there's a lot less debate than you might think, and neither position is anywhere as extreme as the soundbites and op-eds make out. The climate is warming, we have some decent ideas as to what factors are causing it (and they are many and diverse), and it seems human actions are somewhat of a factor. Don't take my word for it though, actually do some reading on your own.

      Jedidiah.
    • Re:Here's the Deal (Score:5, Interesting)

      by Budenny ( 888916 ) on Sunday November 13, 2005 @02:57AM (#14019148)
      "Global warming *is* happening, but factually only in the sense that our planet has been getting warmer"

      I wouldn't dispute that, since about 1800 it has. But there is a problem, which I've never seen adequately addressed, with the IPCC Hockey Stick curves. This the controversy with Mann et al. We do know from historical evidence that there actually was a Medieval Warm period, and the evidence is that it was hotter than now. There was also a cool period in around 1700. Both of these vanish from the record with the IPCC hockey stick curves. Then, if you get into how these curves were derived, lets say just that the derivation is very remote from any observational evidence.

      So two things trouble one. First, the rewriting of history without apparent reason. Second, the lack of any explanation of what caused the Medieval Warm period. Not human activity, that's for sure - or at least, not the industrial revolution. And what caused the decline after it?

      • Re:Here's the Deal (Score:5, Interesting)

        by Coryoth ( 254751 ) on Sunday November 13, 2005 @03:39AM (#14019232) Homepage Journal
        But there is a problem, which I've never seen adequately addressed, with the IPCC Hockey Stick curves. This the controversy with Mann et al. We do know from historical evidence that there actually was a Medieval Warm period, and the evidence is that it was hotter than now. There was also a cool period in around 1700. Both of these vanish from the record with the IPCC hockey stick curves. Then, if you get into how these curves were derived, lets say just that the derivation is very remote from any observational evidence.

        That's a fairly strong claim. I think you'll find that Mann recognises medieval warm periods and cooler periods in the 1700s. The medieval warm period just isn't warmer than present temperatures in his reconstruction based on proxy data. In fact, that's the case for most reconstructions based on proxy data from a wide variety of sources. There are differences in the different reconstructions, but in general there's a reasonable amount of agreement. Don't take my word for it though, here's a plot with 10 different reconstructions [wikipedia.org] along with full citations of the source papers for each so you can check the methodology on each of them. Given the variety of methods used for derivation amongst those reports, from glacier records to tree rings, it's at least resonably convincing.

        As to alternative views - the only evidence I've seen for a significantly warmer medieval period is derived from exactly the same data as Mann's, in roughly the same manner, so if you think one is suspect... What we do have is one report by two Canadians, one an economist the other a businessman, claiming radically different results from everyone else using different slightly techniques. I'm not writing them off, but I would be interested to see a little more work on the issue, especially when there are discussions of issues with their techniques [realclimate.org] (and nice simplified versions [realclimate.org]) that seem quite reasonable.

        None of this is to say that McIntyre and McKitrick are wrong, but one has to ask why you believe them and dismiss the ten other reports by different people that generally agree quite well.

        Jedidiah.
      • It is completely obvious that there have been warming and cooling periods in the past and that we may be in a warming period unrelated to CO2 emissions. People who demand action on climate change aren't disputing that. But we also know for certain that CO2 in the atmosphere has increased, and we also know for certain that increased CO2 causes a greenhouse effect--the only question is about the magnitude of the effect. The magnitude can be between mild and severe. Either way, sooner or later, we are going
      • I read this explanation someplace, I don't remember where exactly.

        The elevated tempratures were the result of mass burning of forests in order to make land suitable to agriculture. After a while the burning activity stopped and agriculture went into production and the CO2 levels stabilized or reduced by being absorbed into the ocean. CO2 levels started going up again as a result of increased population, more burn offs of forests, the industrial revolution and of course the internal combustion engine.
    • There is NO consensus on whether or not man-made global warming is happening- anyone who claims to have "climatologist" friends who say it most definitely is or isn't real

      Of course, there is a consensus on whether man-made global warming is happening; it is basic physics that if CO2 concentrations go up, the temperature goes up, and CO2 concentrations have gone up. The debate is about what fraction of global temperature increases are caused by man-made CO2 emissions and how severe it's going to get in the
    • It looks like some progress is happening here. A few years ago the republicans ( a handy term for people opposed to CO2 reduction efforts) were saying that global warming wasn't happening. Later they tried the "it's happening but it's good for you" argument for a little while. Now the argument is "it's happening but it's not our fault, we can't do anything about it, so let's get back to making lots of money" argument.

      Recently there was a study conducted on ice cores that tracked the amount of CO2 in the atm
    • by RaveX ( 30152 ) on Sunday November 13, 2005 @08:20PM (#14023152)
      Most of what you say is totally unobjectionable, except for this:

      There is NO consensus on whether or not man-made global warming is happening- anyone who claims to have "climatologist" friends who say it most definitely is or isn't real and that all the real scientists agree are just pulling stuff out of their ass (and it's pretty obvious, too, so don't even try to do it).

      Well, here I go pulling stuff out of my ass (and by "my ass" I mean "the positions of the most influential bodies in the field") [my bold].

      From the Position Statement [agu.org] of the American Geophysical Union:

      Human activities are increasingly altering the Earth's climate. These effects add to natural influences that have been present over Earth's history. Scientific evidence strongly indicates that natural influences cannot explain the rapid increase in global near-surface temperatures observed during the second half of the 20th century.

      From the Position Statement [ametsoc.org] of the American Meteorological Society:

      ...Because human activities are contributing to climate change, we have a collective responsibility to develop and undertake carefully considered response actions...

      ...Human activities have become a major source of environmental change. Of great urgency are the climate consequences of the increasing atmospheric abundance of greenhouse gases and other trace constituents resulting primarily from energy use, agriculture, and land clearing. These radiatively active gases and trace constituents interact strongly with the Earth's energy balance, resulting in the prospect of significant global warming...

      ...An overwhelming majority of scientists agree on the following facts relating to the global warming issue.

      * The theory of how greenhouse gases directly interact with atmospheric radiation is not controversial. If no other factors counter their influence, increases in their concentration will lead to global warming.

      * A steady rise in the concentration of greenhouse gases began over 200 years ago and is continuing. Atmospheric concentration of carbon dioxide, the principal greenhouse gas, has increased from pre-industrial concentrations of 280 ppmv (parts per million by volume) to over 367 ppmv in 2000, an increase of more than 30%; methane has increased from 0.7 to about 1.8 ppmv, an increase of more than 150%; nitrous oxide has increased from 0.27 to over 0.31 ppmv, an increase of 16%. Tropospheric ozone is estimated to have increased by 35% since the industrial revolution...

      The first line of the National Academy of Sciences 2001 report titled "Climate Change Science: An Analysis of Some Key Questions" [nap.edu], performed at the request of President Bush:

      Greenhouse gases are accumulating in Earth's atmosphere as a result of human activities, causing surface air temperatures and subsurface ocean temperatures to rise.

      In short... there is no controversy. Yes, there are a handful of very loud people who are attempting to create one, who are assisted by the media's dedication to "balance," which consists of giving equal weight to totally unequal positions. Really, though, in the scientific community, anthropogenic warming is considered to be a fact.

      Now, to be clear, this doesn't mean that we should necessarily do anything about it. The existence of a phenomenon is not de facto support for any particular policy position. But let's not screw around-- the "controversy" over whether global warming is at least partially anthropogenic is manufactured and does not reflect the views of the scientific community.

  • worst summary ever (Score:4, Insightful)

    by PhreakOfTime ( 588141 ) on Sunday November 13, 2005 @02:10AM (#14019031) Homepage

    So greenhouse gases are causing the earth to get warmer, thus increasing the rate of evaporation of water above previous levels.

    And somehow its the water vapor that is released from this evaporation, from increased heating, that is warming the earth?

    If I hit my tumb with a hammer, and it starts bleeding. It would be like saying it is the blood that is causing the pain.

    Worst article summary ever!

    • The analogy is almost correct. Now imagine the blood did cause pain, perhaps even more pain than the initial hammer blow. (Who knows, perhaps you an Alien?)

      But what's the solution?
      A. Soak up the blood temporarily untill it bleeds back out causing more pain again.
      B. Stop hitting your fingers with a freakin' hammer.


  • I think it's time to admit that we're all in a race with each other to use fossil fuels.

    The fact is most of the coal and petroleum will be burned, one way or another. The question is, who gets the benefit?

    Those that race to burn it first get the benefit. Anyone that reduces their consumption suffers with a competitive disadvantage.

    It's a classic tragedy of the commons [wikipedia.org] situation.
    • Anyone that reduces their consumption suffers with a competitive disadvantage.

      No. The cost of many of these items is increasing. There may well be a significant advantage to reducing consumption of oil to alternatives that are cheaper or more stable price-wise in the future. Some OECD economies that are doing well now (at least in terms of headline growth, the figures for real terms GDP growth are different) are quite oil dependent, for example the USA which uses 50% more oil per unit GDP than the average

  • The exhaust from combustion of hydrogen is water vapor. If this is a more serious greenhouse gas than originally thought, can hydrogen really be considered an eco-friendly fuel? We'd probably have to have condenser units in the role of catalytic converters in hydrogen power cars.
  • It's clear from all the discussions in previous articles about global warming that no amount of science is going to convince anyone of anything.

    Therefore, I'm sticking with the eminently reasonable position that global warming is caused by Republicans.
  • by Wonderkid ( 541329 ) on Sunday November 13, 2005 @04:01AM (#14019292) Homepage
    ...I got stung several times by a mosquito, and have the lumps to prove it. Having lived in the UK since 1963, I can confirm having never ever ever seen or been stung by a mosquito in November - they normally appear in the summer months. To any detractors out there, global warming IS happening, but because a number of large corporations stand to profit from it (were the ice sheets are melting), it's just not being given the sort of focus that it should be.
  • Scientists have reported that they have discovered a thick layer of gases and evaporated liquids around the earth which they believe contributes to global warming. They have named this layer of various elements, composed primarily of nitrogen and oxygen, the "atmosphere". It is hoped that further investigation of the atmosphere could lead to a greater understanding of global warming.
  • by cdn-programmer ( 468978 ) <terr&terralogic,net> on Sunday November 13, 2005 @04:14AM (#14019334)
    If you check my posts you will see that I have been saying this for years.

    Most of this is probably due to a lot of land at high elevation. This causes a cooling because water vapour falls out at high elevation and cannot trap the incomming solar radiation. Furthermore we get a high reflection off the snow and ice as well.

    In all likelihood the cooling from the Miocene was caused by mountain building with the himalyan plateau being the latest addition. The Rockys and Andies, Pyrannies, Alps and 2 Hellenic ranges appeared before the Himalain plateau was pushed up. In North America we have the Colorado Plateau.

    As part of this cooling Antarctica froze over and that locked the planet into the current snowball earth. Prior to this freeze over Antactrica was cold - but still had significant amounts of water vapour which trapped solar energy falling during the Antarctic summers. After the freeze over, Antarctica became the dryest continent on the planet - with a huge increase in the loss of solar energy falling on Antarctica. So this is a powerful positive feedback mechanizm that locked us into the current snowball earth phase.

    Since then a lot of erosion has taken place which my have moved us past the equilibrium point. Still - the ice on antarctica and the glaciers at high elevation have kept us locked into the snowball earth phase.

    I suspect that irrigation is causing a warming. It makes a great deal of sense. But offsetting this is the distruction of the rain forests.

    CO2 is negligable. During the ordovician levels of CO2 were 13x to 19x higher than now and the earth cooled.

    Some have pointed out correctly that the sun was not as strong back then. While that is true - there was a fair amount of mountain building during the ordovician (taconic orogany) and this may have been what tipped the planet from the hot house into the snowball phase. The sun was also weaker when the planet came out of the snowball phase a few million years later.

    For over 80% of the last 540 million years the earth has been about 22 degrees warmer on average than now. So it makes sense that the earth will warm up - we just do not know when.

    Another thing is that we have had about 22 ice cycles in the last 2+ million years and typically with a frequency of about every 100,000 years or so. 5 million years ago there were trees north of the Arctic circle in Canada. This is probably true of Russia as well.

    Since we have had a number of ice cycles (the last was at peak about 50,000 years ago) it would make sense that we will have another. If so then we may be within a few 1000 years of another ice age developing.

    It really will depend on where the equilibrium points are and I don't think anyone has any real idea.

    One thing that is really instructive is to look at a globe of the earth that has actual mountains on it. There is one at the Tyrrell Museum in Drumheller Alberta. When you look at this globe and see just how thin the atmosphere really is - 2/3 of it lies below 30,000 feet for instance (Mount Everest) - it becomes very clear that a lot of solar incident energy is simply reflected off into space.

    Get rid of the mountains and you gain a very effective H2O blanket.

    In the tropics at sea level and 35C the absolute H2O vapour in the atmosphere is over 8% (80,000 ppm). This is in contrast to CO2 levels of 365 PPM.

    H2O is a stronger absorber than CO2 by far - in all wavelengths.

    So I frankly do not think CO2 is even a factor to be honest. The models used by the IPCC do not take into consideration that water vapour levels may be changing. When your most significant variable is not handled properly then your model isn't very believable.

    From a paleoclimate standpoint - CO2 can change climate. It did several times in the Precambrian. The thing is that in order to do this the CO2 levels had to climb to many 1000 PPM. This occurred back then because so much of the earth froze over that even the oceans may have frozen r
    • Very interesting but (Score:3, Interesting)

      by kf6auf ( 719514 )

      You have negleted to mention one thing: greenhouse gasses only act as such at certain wavelengths depending on their absorption spectra. Therefore, there is a point at which adding more of any greenhouse to the atmosphere does not change the absorption spectra of the atmosphere since the absorbable light from the sun is already being fully absorbed.

      I was unable to find a website explaining this or giving examples, but I remember being told at one point by a professor (2 years ago) and shown the data/grap

      • I would want to look at details. There are huge expanses of the planet that are very dry. To integrate this is a very very good idea.

        Water vapour above about 15,000 feet is practially non-existant. I'm not sure of the boundry and of course this is a continous function.

        If your prof said this then he was thinking of some specific areas. I would expect that is subtropical to tropical SE asia that H2O absorption is 100% effective. THere is probably a surplus.

        This will explain why global warming will affect
  • by zan2005 ( 930678 ) on Sunday November 13, 2005 @04:31AM (#14019371)
    There seem to be a few things missing in this discussion:

    1. The fact that most of the warming associated
          with global warming is directly forced by water
          vapor is well established, going back at least
          as far as Arrhenius's 1895 paper often credited
          with "discovering" global warming.
          (original paper at:
                http://geosci.uchicago.edu/~archer/PS134/arrhenius .1896.climate.pdf [uchicago.edu]
            )
            i.e. this result is CONSISTENT with our understanding
            of global warming.

    2. Increases in atmospheric water vapor are tightly tied
          to temperature. The saturation specific humidity
          (the amount of water air will hold) increases
          exponentially with temperature (an implication of the
          Clasius-Claperyon relationship). Thus when you increase the
          temperature of the atmosphere by dT (by, for example, adding
          some CO2), more water vapor evaporates into the atmosphere,
          amplifying the warming.

    3. This effect, known as the water vapor feedback, has been in
          our climate models from the beginning (at least as far back
          as 1895), and produces results consitent with observations.

    4. The cited Geophysical Research Letters paper uses observations
          to estimate the strength of the water vapor feedback and
          finds that it is strong (even stronger than most models
          predict). It is also a step in the process
          of understanding climate change on a regional level.

    Z
  • by olethrosdc ( 584207 ) on Sunday November 13, 2005 @06:21AM (#14019582) Homepage Journal
    Why does he say 'it is water vapor rather than caron dioxide that causes warming in europe'? The next sentence makes it clear that this is not the case, so the first sentence should have been omitted as it is misleading.
  • by aridg ( 441976 ) on Sunday November 13, 2005 @08:56AM (#14019912)
    Every climate scientist knows that water is responsible for most of the greenhouse effect -- this is not news.

    The important point to remember is that in the lingo of the climate scientists, water is a "feedback" rather than a "forcing". CO2 is considered a forcing because you can affect the climate by adding to or removing it from the environment -- the levels of CO2 in the environment are not affected much by climate processes.

    Water is completely different: there is so much water available on the surface of the earth that adding extra water to, or removing it from, the environment -- say, by building big condeners that feed storage tanks, or by building pumps that spray water into the air -- won't make much difference, at least once you turn the pumps or condensers off.

    You can read all about it here [realclimate.org].
  • by ONOIML8 ( 23262 ) on Sunday November 13, 2005 @12:11PM (#14020700) Homepage
    We're all gonna die!

    When I was a kid the world was going to be destroyed by nukes. Either WWIII would happen and MAD would do us all in or a nuclear reactor would go out of control somewhere and destroy everything. Pay attention kids, that's really the way it was for us. They taught it to us in school, it was the theme of many of our Saturday morning cartoons, it was in every magazine and book and all over the TV.

    That myth was slowly shattered over time. The Soviets had a couple of nuke reactor problems and so did we. Life went on. Then the USSR fell and the idea of MAD went away with it. Suddenly nukes didn't seem so frightening. People started to wake up to the fact that life was even going on in the cities that the US had nuked in WWII.

    So what do we do without the threat of nukes? Without the fear of nuclear death we would have to accept the fact that the fate of every living thing might be in the hands of a higher power or, worse yet, not in the hands of anyone at all. As humans we can not accept that. Something or someone must be in control and we like it best if we can imagine it to be us as we had imagined it with nukes.

    So now there is some data that can be stretched to imagine that the climate of our planet will kill us all. That's even bigger and more scary than nukes. Children can be taught to fear that with ease. Better yet, our ego will allow us to believe that we can control it, that we caused it. And most of us can accept as fact that although we caused it there is nothing we can do to correct it.

    Yes, we're all going to die.

  • by Maxo-Texas ( 864189 ) on Sunday November 13, 2005 @01:20PM (#14021038)
    What happens when we go to a hydrogen economy?

    Lots of extra water vapor.

    A little water is good for you. A lot of water will kill you.

    A few cards using hydrogen are probably good for us. All cars using hydrogen needs to be investigated to see if it puts out significantly more water vapor than our current gasoline cars (which also put out water as a part of burning the fuel).
    • What happens when we go to a hydrogen economy?

      Lots of extra water vapor.


      Moderation fails again.

      This isn't insightful. It's pretty much wrong (or was maybe meant to be humorous). This is like saying that if it rained more we'd all get killed (by the intense global warming that would results from all that water vapor! Clouds!). Water is a cycle that's basically at equilibrium. We aren't gaining or losing any to/from space (except tiny, tiny, insignificant amounts). We aren't going out of our way to find, dig

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