Those terrible twins of climate change, CO2 and H2O

One of the most commonly held misconceptions about the man-made global warming hypothesis is that temperatures must increase every year and evenly over the world. No one knowledgable about climate issues would seriously claim that, so it’s an obvious strawman.  The question is, why do temperatures fluctuate so much and does global warming explain this? Indeed it does!

The process begins with the slight increase in CO2 in the atmosphere known to be caused by human emissions. Because CO2 traps slightly more heat, it also causes more water to evaporate. Water vapor is also a greenhouse gas, so that causes a feedback loop, in which the temperature increases further, causing more water to evaporate. In the summer months, the result is much hotter weather than you might expect from CO2 alone.

But H2O has an opposite effect in winter. As temperature drops, the increased amounts of H2O forms clouds, which block sunlight and thus cool the earth further. Winters will be even colder than one would expect, plus there would be increased precipitation, including snow.

As long as the average temperature over the course of a year at a certain place or region is below the melting point of water, then global warming actually has the paradoxical effect of causing colder winters, more snow and thus increased ice in certain places. It is where the average annual temperatures have risen above the melting point of water that we see glaciers retreating. And the hotter summers at the northern ice cap are nothing to ignore, for its melting away will still have a tragic effect on polar bears.

In the southern hemisphere, global warming has had less of an effect, and this can be explained by geography. There is far more land up north than down south. Land radiates heat, while oceans absorb it. Also, the Arctic Ocean is water surrounded by warmer land, while Antarctica is frigid land surrounded by cold oceans that insulate it from warmer regions. So it stands to reason that the Arctic Ocean will melt long before the Antarctic ice cap does, and that there may even be some increase in Antarctic ice for the reasons I explained above.

If there was no CO2, or any other greenhouse gas in our atmosphere, the average temperature on Earth would actually be below the freezing point of water, thus the oceans would be frozen over and life on land would be impossible.  And if there was no H2O to form oceans and absorb CO2 from the atmosphere, then CO2 would have accumulated so greatly in the atmosphere from volcanic eruptions over billions of years that we would have experienced temperatures too high for carbon based life forms to survive, thus we would already be like Venus. The abundance of water on Earth, plus the small amount of CO2 in our atmosphere, provide the delicate balance that maintains life on Earth. But too much CO2 can be as much a problem as too little, hence our concern about how much longer it may be before we reach a tipping point in the climate change problem.

If  the solar activity drops, while the CO2 levels remain high AND the H2O levels are also high, the end result is warm summers and VERY COLD WINTERS!

But when the Sun roars again, all else being the same, we will get: Mild winters and VERY HOT SUMMERS!

Although both CO2  and H2O are indeed greenhouse gases when both are in their gaseous state, in practice only CO2 is always in that state in the atmosphere. That is why CO2 is indeed the most important greenhouse gas, despite it being less prevelant than water vapor. Global warming denialists have exaggerated the greenhouse role of H2O to justify ignoring CO2. That is flat out dishonesty.

The proportions and molecular weights of the most common components of the Earth’s atmosphere are:

  • Nitrogen (78%) : 28
  • Oxygen (21%) : 32
  • Argon (1%) : 40
  • CO2 (0.039%)38
  • H2O (0.4%)18

Note that! Water vapor has less than HALF the molecular weight of CO2! And that leads to some serious results.

Since nitrogen and oxygen form nearly 99% of the atmosphere, the average molecular weight of it will be between 28 and 32. CO2 is heavier than that average, while water vapor is MUCH lighter than that average. Thus water vapor will tend to rise much more than the other gases listed.

Because CO2 is lower in the atmosphere, it traps heat closer to the surface. Trapped heat causes evaporation. The H2O quickly rises and as it does, it cools. In some cases, the relative humidity of the rising H2O exceeds 100% and that results in the formation of clouds, which block and reflect sunlight. And this nullifies H2O’s greenhouse effect and it instead becomes a cooling agent, all the way down to the surface. It is common knowledge that cloudy days are cooler than clear ones. The only times the greenhouse effect of H2O is really significant is at daytime when the sky is clear, and at night when the sky is cloudy. In the latter case the clouds hold in heat that would otherwise escape when the sky is clear.

Thus this statement by ICECAP, a denialist front group, is falsified:

CO2 is the most important greenhouse gas.

Not even close. Most of the greenhouse effect is due to water vapor, which is about 100 times as abundant in the atmosphere as CO2 and thus has a much larger effect.

This is misleading. The overwhelming tendency of water vapor to rise, to form clouds, and to shield the Earth’s surface from the Sun’s rays make the reality of the issue far more complex. CO2 by nature actually has the larger effect because it NEVER forms clouds and thus can ONLY be a greenhouse gas. It operates regardless of the weather.

Of course, that will not deter denialists. They will still say, “Well, if CO2’s greenhouse effect is opposed by the cooling effects of water clouds, doesn’t that mean CO2 can’t change climate?” But that is wrong too. The skies are not always cloudy. Increasing CO2 amounts by human activities DO trap more heat, which goes into the oceans and into other bodies of water, including the Arctic Ocean. And that stored heat is why the Arctic ice cap has been melting away. That is also why we had that incredibly strong El Nino of 1998 and why we had so many devastating hurricanes a few years ago. In deserts, where there is hardly any water, the cooling effects of H2O do not apply and those areas will be even hotter and drier. And in areas where there is already plenty of rain, there will indeed be more rain, resulting in flooding in certain regions.

In short, the denialism of global warming/climate change is based entirely on ignorance, dishonesty, and hypocrisy. We need to debunk and do away with it for good!

18 thoughts on “Those terrible twins of climate change, CO2 and H2O

  1. Pingback: ICECAP, a group of fake climate experts « Dale Husband’s Intellectual Rants

  2. Pingback: Thermal backlash « Dale Husband's Intellectual Rants

  3. Pingback: Twitter Trackbacks for Those terrible twins of climate change, CO2 and H2O « Dale Husband's Intellectual Rants [] on

  4. Pingback: A flawed and misleading video about global warming « Dale Husband's Intellectual Rants

  5. You are right that H2O is a strong greenhouse gas, due to its absorption spectrum. I didn’t really understand the molecular weight argument. I have analyzed the CO2 greenhouse effect (here). You might find the results surprising. Sorry that I don’t include the secondary effects of H2O.

    • You made several errors in your analysis, Wrauny.

      You admitted: “My analysis does not address the hypothesis for the potential magnifying effects of CO2 (i.e., slight CO2 warming causes more water vapor in the atmosphere. The water vapor acts as a stronger greenhouse gas than CO2.).” IT SHOULD HAVE!

      You also claimed: “Melting glaciers and polar ice caps cools the atmosphere (Most likely by a very small amount).” Not only is this nonsense, the melting ice exposes open water and land which is darker and therefore absorbs much more solar radiation than the ice did, resulting in greater warming as the surfaces emit more heat.

      “Other gases (Methane, etc.) from human activities were not included in my analysis. If they are the real problem, than I think we should stop talking about CO2 and focus on emissions of these other gases.” ALL those gases are a problem. You don’t cherry pick like that! Even Al Gore did not.

      Can you explain why in your last chart the Radiant Intensity (W/m2) is depicted as being slightly less as the CO2 amounts skyrocket? That makes no sense to me. For the analysis to be run consistently, the Radiant Intensity (W/m2) should be the SAME under all circumstances. Thus, I have little regard for your use of MODTRAN to support your claims. The test seems to be rigged.

      • In the last table, the emitted Radiant Intensity from the earth is decreasing due to increasing CO2 absorption. In order to balance the Radiative Forcing (incoming Solar Irradiance minus outgoing thermal and reflected radiation), the surface temperature of the earth was increased in MODTRAN so the the radiant intensity matches the baseline value.

        Note that I updated my blog to include the IPCC definition of radiative forcing, which excludes this balancing effect (increased thermal radiation from a hotter earth). My blog was really a criticism of that definition, thus the glossing over other factors (which you justly criticized).

        I apologize if the language I used was provocative and I regret this. I am concerned about the environment, but I feel that the sensationalism and politicization of this issue is preventing us from being reasonable in our solutions.

        (Dale Husband: Your apology is accepted.)

  6. Pingback: Idiocy on Watts Up With That! « Dale Husband's Intellectual Rants

  7. Well as one of those filthy denier types,…

    I go along with the basic outline.

    But CO2 is 0.0383 per cent by weight or 0.06 per cent by mole
    for dry air. Air has on average 1 per cent water vapor.

    So we have as a ratio 6 molecules of CO2 for every 10,000 other molecules.
    Now for those radiant absorption curves that indicate that CO2
    has 32 per cent of the absorption spectrum, can you qualify what are the
    parameters of these measurements. I suspect that if air was used there would
    be no CO2 reading due to the 6/10000 washout.

    Even this, what portion of CO2 is human compared to the carbon cycle?

    I see a fraud here along the same lines as the homeopathy fraud,
    an exaggeration to extreme of the influence of a molecule.

    There cannot be any feedback (+ or -) of a entity that is vastly overwhelmed
    by similarly acting molecules.

    CO2 is a scarce resource that the planet has been sequendering for 3 billion
    years. CO2 is not a pollutant. As good citizens of the planet we need to be
    at peace with the workings of our blessing and not be distracted from the
    ever real problems we have to deal with.
    Fancy suggesting (others not here) a fix in the form of what we knew to be nasty and have
    seen the results from its reduction … sulphur dioxide.

    (Dale Husband: CO2 is indeed a trace gas, but it can still have a profound effect. Are you aware that there is even less ozone in our atmosphere than CO2, yet it is classed as both essential to life (since it forms a layer to shield us from ultraviolet radiation) and as a pollutant at ground level? Clearly, you haven’t read my other blog entry on the matter of CO2’s role as a greenhouse gas, have you? When you have, you will be much less ignorant, I hope. )

  8. hh, th sll ld zne cnrd. f crs knw tht y r sng th rgmnt f mgc smlrt? zn nd crbn dxd r ntrl dffrnt mlcls, hv dffrnt srcs, nd srv dffrnt fnctns n th tmsphr. Th mprtnc nd fnctn f n hs bsltl n brng n th mprtnc nd fnctn f th thr. B r lgc snc n nt cn crr 50 tms ts bd wght, cn bnch prss Tyt.

    hvn’t rd r blg ntr thr, bt ‘m nclnd nt t bsd slly n tht bt f sllnss.

    (Dale Husband: If you cannot disprove something with valid scientific evidence, ridicule won’t help you at all. My argument about ozone was a direct response to the denialist claim that CO2 cannot change the global climate due to its being a “trace gas”. Nothing more or less. But there are some people even more stupid that say the alarmism about the ozone layer decades ago was unwarranted too. Those bastards are nothing but apologists for corporatist dogmatism and they are fit only to be stomped on.

    P. S. You are now banned from this blog. Every comment you have made here could have been made by a twelve year old punk!)

  9. This is strange. I didn’t make this post (I can’t even read it). Someone appears to be using an identical appellation to comment here.

    My only comment ever on this site was on the Iran/Afghanistan/Iraq thread, which was simply to point out that things always go better in theory than in practice. I apologize if you thought that juvenile.

    So am I banned, or should I simply change my post name?

  10. Pingback: A banned person lies to me! « Dale Husband's Intellectual Rants

    • Mainly because I’ve been looking for a job and playing online games like World of Warcraft for a couple of hours each day to take my mind off being unemployed. Blogging is a lesser priority now and will remain so until I get a new job.

Leave a Reply to Ed Darrell Cancel reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s