Data suggests Global Temperature tracks Aviation Fuel Consumption

From the “this is not the looney chemtrails idea” and the “how much of this can be attributed to climate jet-setter Bill McKibben?” department, comes this data.

Jet contrails as seen by satellite. Credit NASA Langley Research Center

Jet contrails as seen by satellite. Credit NASA Langley Research Center

Guest essay by Don Spencer

The recent “hiatus” in the global temperature record has thrown a dark cloud on carbon dioxide’s position in explaining climate change. Whereas the temperature record has been relatively constant for the last fifteen or so years the atmospheric carbon dioxide concentration has increased more-or-less unabated casting doubt over its influence. Climatologists have been scrambling to explain the temperature hiatus as just that, a hiatus or pause, where the greenhouse energy is temporarily stored away in the ocean to [wreak] its vengeance on us at a later time.

But maybe the simpler explanation is that we are backing the wrong gas and water vapor is the really important greenhouse gas, after all it currently accounts for more than 85% of the current greenhouse effect that supports life on this planet. Water vapor is a more effective greenhouse gas than carbon dioxide by virtue of its asymmetric molecular structure that allows more vibration modes hence more opportunities to capture and adsorb radiant energy.

Andrew Dessler and colleagues from Texas A&M University in College Station confirmed that the heat-amplifying effect of water vapor is potent enough to double the climate warming caused by increased levels of carbon dioxide in the atmosphere

The trouble is that global water vapor concentration is difficult to measure and even harder to pin on humans. However since WWII humans have been conducting a great atmospheric seeding experiment. Thousands of large flying machines have been circling the earth day and night releasing millions of tons of water vapor into the upper atmosphere. The fuel used is typically kerosene (C12H26); when a molecule of kerosene burns in oxygen we ideally get twelve molecules of carbon dioxide and thirteen molecules of water vapor and a bunch of heat.

To estimate the amount of water vapor and carbon dioxide released we can look at the global aviation fuel usage from 1984-2010 which was obtained from Note these statistics include both kerosene and naphtha aviation fuels.


We can see the consumption was less than two million barrels/day in 1984 and has risen to about five million barrels/day in 2010. The growth rate since about 2004 has been modest due to significant improvements in airliner efficiency. In the next figure the GISS global temperature has been plotted against the aviation fuel consumption. The correlation is quite good, better in fact than that for carbon dioxide. So if we all stop flying will we save the earth? Maybe, maybe not, as correlation alone does not necessarily imply causality but we do have a viable hypothesis, water vapor is a significant greenhouse gas and we are injecting vast quantities of it into the atmosphere via air travel. The temperature hiatus (if it is a hiatus) is explained by lower consumption and emissions due to more efficient jet engines. If this mechanism were correct and we did stop emitting water vapor then the atmospheric water vapor would soon reach a lower equilibrium and the temperature should fall back.


It is interesting to speculate what might happen if we do back the wrong gas. We shut down our fossil systems; coal-fired power stations, hydrocarbon based transportation and replace these with say renewable or nuclear energy and develop a “green” hydrogen economy producing nothing but “clean” water vapor. We would stop our CO2 emissions but vastly increase our water vapor output. This could actually make the earth warmer so we must make sure we get it right. The right answer is not known, more real science is needed with all hypotheses on the table.


160 thoughts on “Data suggests Global Temperature tracks Aviation Fuel Consumption

    • Real time aircraft movements at Heathrow –,-0.46/13

      (Hover cursor over plane for its call-sign, click for full details. You can drag & expand map to give the whole worlds commercial aircraft positions & identify each one. Times out after 30min, just reload page.)

      At full world expansion it’s staggering how many planes in the air at any given time.

      • Actually, remove the /sarc. One of the mechanisms for the Sun’s influence on climate, besides the obvious, is that changes in the Sun’s magnetic field increase or decrease the dosage of cosmic rays hitting the atmosphere. The cosmic rays (actually ions traveling at close to light speed) end up triggering cloud formation, and it is the increase or decrease in high-altitude clouds that effect the climate. An increase in aircraft traffic, therefore, emulates an increase in cosmic-Ray cloud formation.

      • Cosmic rays also turn Nitrogen in the atmosphere into radioactive Carbon 14 which AGW ers claim is falling in ratio to C12 and C13….

    • I am confused. They are saying that more water vapor is more warming, or at least that was how I understood the carbon dioxide/water vapor feedback to be. So now they are saying that the high level water vapor is causing the cooling? So not only do we have magical carbon dioxide but we also have magical water vapor and they combine to form magical weather and magical climate that magically explain everything extreme, so don’t burn coal for energy. Now I understand why they move the COP(x) around the world. So everyone can fly to the next one and in so doing. prevent the world from having a fever.

      • There is little to no water vapor in the stratosphere, clouds are very rare, but clouds are either water or ice, not vapor which is invisible. Aircraft exhaust is enriched in CO2 and water, the water quickly freezes into visible contrails.

        SOFIA’s flight capability allows it to rise above almost all of the water vapor in the Earth’s atmosphere, which blocks some infrared wavelengths from reaching the ground. At the aircraft’s cruising altitude, 85% of the full infrared range will be available. Stratospheric Observatory for Infrared Astronomy

        At lower elevations, there is considerable water vapor in both the clear sky and in clouds, so whether lower elevation clouds warm or cool is a matter of emerging reseach.

    • Has anyone ever run the actual air traffic numbers? The Honolulu International Airport opened in 1960-the same year Mauna Loa started recording “CO2”. Traffic between 1960 and 2006 increased from 222, 000+ landings and takeoffs at HIA to over 20,000,000! Thats a lot of additional CO2 and water vapor over Mauna Loa (which sits on a volcano too)

      What about the other CO2 stations and air traffic increase?

  1. I might accept that we are contributing to the atmospheric water vapor and therefore are contributing to the “Green House Effect”, although our contribution may not be having a measureable effect.

    Since 1850, however, the atmospheric temperature rose at a similar rate well before we were began global jet travel, which makes me highly skeptical that our contribution is more than extremely minor.

    • OK, before everyone starts building on the CAGW false premise, try this ….

      Greenhouse gasses (including CO2 and water vapor) absorb IR and then emit IR downwards, thereby warming the Earth, right? Everyone knows that of course. Problem is they also emit IR upwards – into space. ‘So what?’ you say. If you increase greenhouse gasses, the IR emissions will obviously also increase, both downwards and upwards, right? Of course, everyone knows that as well. OK, if IR emissions into space increase due to increases in greenhouse gasses and the energy input from the sun does not change then the temperature of the Earth will do what? Riiiiiiight! The temperature of the Earth will go doooown!

      Greenhouse gasses are radiative gasses – they radiate IR in all directions, not just downwards. They radiate into space as well as back to Earth. Obviously,increasing IR radiation into space will cool the Earth – not warm it!

      Now, armed with this apparently new information, re-read the post again and try not to laugh out loud when you see how far they have built on that CAGW false premise!

      Google ‘isotropic’ and then reconsider the greenhouse effect – you don’t need to be a rocket scientist for the penny to drop.

      • Um, I don’t think so. The greenhouse effect comes into play because without any IR active (i.e. greenhouse) gases the atmosphere would be IR transparent and ALL IR leaving the ground would radiate to space. The greenhouse effect means that some of that gets reradiated back to Earth. The greenhouse effect is real alright – just small, easily saturated and not apparently amplified by water vapour and clouds as the cagw hypothesis erroneously assumes.

      • Bernard, what you are failing to understand is the balance.

        Starting with the trivial case of no atmosphere, All IR Radiation from Earth’s temperature will go up and never come back down.

        Now, add an atmosphere. The Sun is still beating down. The blackbody radiation is still going up. However, some is absorbed in the atmosphere by the gases. Once it absorbs, half re-radiates up, and the other half re-radiates down, going back to the surface. This heats up the surface until the total amount leaving the atmosphere comes into balance.

        So, the effect is that there is an increase in temperature based on the amount of upwelling radiation that is absorbed. Increase absorbed radiation and you increase the surface temperature. Other effects, such as cloud cover, fluid dynamics, and all the rest make the answer for magnitude much more complicated, but it does not change the direction of the effect. Adding CO2 to the atmosphere will warm it. As for how much, I’ll leave that lecture to Viscount Monkton.

        As a general rule, If you have an objection based on elementary physics, typically it’s your understanding that is the problem.

      • Good try, and almost right.

        For the upper atmosphere you have it right, it increases the emission of radiation to space. Thus the upper atmosphere is cooled just as you say.

        For the lower atmosphere, the upward radiated photons get absorbed by other GHGs instead of making it to space. Thus for the surface / lower atmosphere, you get warming.

        The above is standard atmospheric radiation physics that the consensus AGW warmists would agree with conceptually (there may be argument about the details of a quantitative analysis, but that’s the basics.)

        Relative to this discussion there is 1 huge question:

        – Is the water vapor effect from jets being felt above or below the altitude where the transition from warming to cooling is?

        My guess is that as long as the air is thick enough to allow a jet to fly, it is the warming portion of the atmosphere, but answering the question is non-trivial.

      • You have to consider the emissivity and the spectral qualities of the heat sources relative to the atmosphere.

        The surface of the planet converts visible light to 15um IR. CO2 just happens to be more opaque in that spectrum.

        Of course, it’s still true that solar radiation is being blocked more with increasing CO2, and many measurements back this up.

      • At the surface half the radiation is above the horizon. As you gain altitude a greater proportion of radiation is above the horizon because the horizon becomes a downward angle. Ergo, the chances of CO2 radiation leaving the earth system is a function of altitude and most CO2 is well above ground level.

      • looncraz
        According to Wein’s equations the emitting surface must be must be at about minus 80 deg C to peak in the 15 micron band. I don’t know how wide those emissions bands are but seems unlikely that CO2 would warm anywhere other than very cold areas of the globe where I am sure it would be appreciated!

    • We can see the consumption was less than two million barrels/day in 1984 and has risen to about five million barrels/day in 2010.

      5 m * 365 = 1,825 m barrels per year.

      Evaporation of water from the surface of the earth is the main process providing water vapor transport to the atmosphere. On average 1,130 mm (or 577,000 km^3) of water are evaporated from the surface of our planet during a year.
      Evaporation of water from the surface of the World Ocean and land of the planet is the main process providing water vapor transport to the atmosphere. Evaporation of water takes much heat (1.26 x 10^24 joules), or about 25% of all the energy received at the Earth’s surface.

      1,825 m barrels converts to 0.29015 km^3 (

      0.29015 km^3 into 577,000 km^3 is not even a rounding error. [And water vapor is only a fraction of the total.]

      If this mechanism were correct and we did stop emitting water vapor then the atmospheric water vapor would soon reach a lower equilibrium and the temperature should fall back.

      But nature is a bit lazy and will only carry so much water, then she sheds a bunch of heat energy way up high in the sky, and the water falls down. The minuscule fraction of man made contribution of water makes no difference.

      • But our CO2 emissions are just a rounding error too! “Some say” (h/t Top Gear) that that rounding error is driving change, so why not water instead? At least it correlates, which is better than with CO2 :).

      • “We can see the consumption was less than two million barrels/day in 1984 and has risen to about five million barrels/day in 2010.”

        And they want to stop Keystone at ? what? Less than a million barrels a day? At least a pipe line doesn’t emit vapors at that rate.

  2. Doesn’t help with the 1930s warming or the mid 20th century cooling though does it ?

    Nor the Roman Warm Period, Dark Ages, Mediaeval Warm Period and Little Ice Age.

    More thought required.

  3. Ok, five million barrels of oil. That’s 790 million liters. In atmospheric terms that’s nothing. You don’t even need to know exactly how much water vapor per liter of kerosene you’ll get, it’s a rounding error.

    • Well, there can be some multiplicative effects. For example, the water vapor and combustion products that makes contrails, when applied to supersaturated air, creates many more ice crystals than the water released from the fuel. Of, course, that’s expected to reduce temperatures by increasing albedo.

      With adequate handwaving, you might be able to claim that the ice crystals settle downward leaving behind merely saturated air. However, that snowfall generally evaporates, so you may not be removing water vapor at all.

    • If we are concerned about manmade water vapour emissions, this is a very small percentage of the water vapour that man emits as a consequence of burning fossil fuels ie., those other than coal (which produces only a small amount of water vapour as a by product of cooling) such as burning natural gas lpg etc.

      The IPCC does not count manmade water vapour because apparently it has a very short half life measured in weeks. However, that misses the point since man burns Gas on a 24/7, 365 days a years basis, and hence irrespective of the half life of water vapour, we are emitting and replenishing copious amounts of water vapour every day of the year. The amount of water vapour that is in the atmosphere today, as a consequence of manmade activity is considerably more than was the case say back in the 1920s.

      So if one is a signed upped to the GHE theory, one has to question whether burning gas is better than burning coal. Gas produces far less CO2 but then again, it produces approximately an equal quantity of water vapour, and water vapour is a more potent so called GHG. So what is the net effect?

      • The IPCC does not count manmade water vapour because apparently it has a very short half life measured in weeks. However, that misses the point since man burns Gas on a 24/7, 365 days a years basis, and hence irrespective of the half life of water vapour, we are emitting and replenishing copious amounts of water vapour every day of the year.

        Somehow this doesn’t seem to get mentioned very often (if ever).

      • @richard verney January 6, 2016 at 5:53 am

        Also, they say water vapor isn’t a “forcing”, it’s naturally balanced.

        OTOH, it’s a “feedback”.

    • “we are injecting vast quantities of it into the atmosphere via air travel.”

      Vast quantities? Compared to what? All the water vapour in the worlds atmosphere? I think the exaggeration is much greater than previously thought.

      • Stephen,
        Humanity is large – but our Planet is huge.

        Just try sailing oceans at 15 knots – it takes days [of 24 hours, ships don’t stop at night] to get anywhere.
        From the Oil Gulf to NW Europe, via the Cape of Good Hope, is about 30 days – fifty days at economic speed of about 9 knots.


      • “we are injecting vast quantities of it into the atmosphere via air travel.”

        Vast quantities when compared to NO quantities prior to human flight?

  4. Interesting hypothesis. Mankind can and does effect the atmosphere/weather/biosphere with his activities. Increasing atmospheric CO2 is having a large consequential effect on C3 plant growth. I’m guessing the natural variations in water vapor in the boundary layer where most jets fly simply overwhelm any exhaust contribution. Huge amounts of water vapor get pumped into the boundary layer by normal weather phenomenon. Lets not give the greenies any new causes without cause. More research is needed.

    • Ok…now add in all the OTHER ways that humans add water vapor to the atmosphere. Almost every form of combustion produces water vapor. Factories release steam. Etc…and the warmer the planet gets, the more water vapor in the air increases by evaporation. Not blaming humans for anything…just saying…it ain’t just JETS.

  5. What if there is no cause? What if we decide that there is nothing to be explained? The fluctuations are random. The system is self-regulating, What if climate should be treated like weather. When we have a heat wave we rarely look for an external cause.

    • Yes. Since the data is concave upward (section of a parabola), you should be able to get a nice least squares fit with ax^2 + bx + c.

    • I am certain that plotting an anomaly vs a daily quantity is nonsense! This is an abuse of statistics.

      • You beat me to it.

        Calculating anomalies requires there to be “correct” values, but there aren’t any correct temperature values from which to deviate. So this is junk-science.

      • David Riser said-
        “I am certain that plotting an anomaly vs a daily quantity is nonsense! This is an abuse of statistics.”
        You said-“You beat me to it. Calculating anomalies requires there to be “correct” values, but there aren’t any correct temperature values from which to deviate. So this is junk-science.”

        Trend line- “a line indicating the general course or tendency of something, e.g., a geographical feature or a set of points on a graph.”

        It’s entirely possible and scientific, to plot a TREND LINE on ANYTHING in which you want to indicate a “general course or tendency”.
        The trend line has NOTHING to do with whether or not the data points (be they anomalies or actual correct temperature values) are valid, or correct, or not. A trend line is simply a method that indicates movement.

  6. What about polar amplification? Not many air planes there, but it is the most active geomagnetic storms (caused by solar activity) region.

  7. You have to also take into account the fact that these emissions create a lot of vapor trails that block sunlight. These trails are visible in the photo that is part of the posting. I seem to recall a report saying that during the flight stoppages that occurred after the 9/11 terrorist attacks, the contrails disappeared and caused an increase in the amount of sunlight reaching the ground.

    So, an extra dollop of super-GHG increases heat retention, but the haze it produces reduces the amount of heat that can be retained. Isn’t this called “feedback”?

    Just sayin’.

  8. This isn’t science; it is pure speculation. To be science it must have scary numbers. For example, if you calculate the amount of global warming caused by the COP21 air travel (expressed in units of Hiroshima atom bombs.), that would be science. If you project the effects of future COP meetings, with the number of attendees increasing at the prevailing rate from COP1 out to 2050, you should be able to show we are approaching a tipping point where 50% of the world’s population will be attending COP56 and dumping more water vapor in the high atmosphere than all of civilization up to 1970.

    Then computer modelling studies will demonstrate that the heavier water-laden jet stream “might” descend to ground level and we “may” get 100-mph winds at the surface, which “could” devastate all the trailer camps set up for “informal permanent visitors of diverse linguistic origins” (soon to be the only acceptable term for what used to be called “illegal aliens”). And they “may” blow down all the windfarms we will be depending on for 50% of our electrical power.

    Also you must acknowledge all contrary evidence. For example: every time Al Gore files some place in his private jet to promote global warming theory the local temperature drops, often quite significantly. Unless explained this would seem to contradict your theory.

    Finally, to be science you must show this theory conforms to the consensus view. This is done by a carefully-controlled ideation survey only available on consensus websites that shows people who believe this theory have a very low correlation with people who believe the moon landing was a hoax, or that Kim Kardashian is a real person.

  9. It would be interesting to curtail all CO2 emissions and see how fast our invigorated biosphere reduces atmospheric CO2 from 400 ppm back to, say, 285 ppm, with a concurrent 15% drop in world-wide foodstuff production. I predict widespread starvation, so it wouldn’t be a good exercise at all.

  10. There is at least one path to greatly reducing airplane water emissions. Airbus has taken an interest in LENR (Low Energy Nuclear Reactions) and has cosponsored one symposium on LENR research.

    They’ve been filed a German for part of what they envision in 2013 for a LENR powered engine. says in a Google translation:

    To provide an environmentally friendly, suitable for the transport sector thermal energy source, the invention provides a power-generating device (10) for generating heat energy by an exothermic reaction in the form of a LENR by using a metal lattice-assisted hydrogen process, comprising: a reaction vessel (14) with a reactive LENR material ( 45) containing for carrying out the exothermic reaction, the reaction chamber (16), a field generating means (18) for generating a field in the reaction chamber (16) for activating and / or maintaining the exothermic reaction, a heat transfer means (20) for transferring heat into and / or from the reaction chamber (16), an operating parameter detecting means (28) for detecting at least one operating parameter in the reaction chamber (16), and a controller (26) which is adapted to the field generating means (18) and / or the heat transfer means (20 ) to control a function of the detected operating parameters for the stabilization of the exothermic reaction or regulate.

    See for more.

    More recently, Andreas Rossi has done some design work on such a beast, he’s taken more interest in it lately, see

    Take it all with a large grain of salt!

    • Rossi is a convicted con artist, whose claims for ECat conversion of hydrogen plus nickel into copper have been thoroughly debunked. Wrong isotopes in the samples he provided.
      That said, both NASA and Airbus think LENR (weak rather than strong force) is real. Explained by Widom Larsen theory. Substanial experimental evidence from, among other places, US Navy. The question is whether it can be scaled to something useful. Third example in the recognition chapter of The Arts of Truth.

    • I was not aware that LENR produced anywhere near the temperatures needed for a direct air cycle aircraft engine (above 800°C). I haven’t been following LENR (seems like too much smoke & mirrors), but I don’t recall it has even been claimed to produce enough heat for super critical steam turbines (above 500°C).

      • Here’s one in a thermal runaway destructive test. The external shell is alumina. I don’t believe Industrial Heat (Rossi’s partner and mostly real company) has used a “hot cat” to make steam yet.

    • Here in California, I’m surprised it hasn’t already happened. Don’t tell Mary Nichols (head of the CA Air Resources Board)–CARB) that H2O is a greenhouse gas–she’ll tax/ban it. As an aside, I’ve subscribed to CARB’s emails re their activities. The degree of control they want over EVERYTHING is mind-boggling. Long past time to disband it (and/or limit its control to particulates–oh wait–then they’d try to tax/ban dust).

    • The old saying is, “The solution to pollution is dilution.” As such, real air, water, and soil pollutants such as mercury, lead, particulate carbon soot, cadmium, radium, radon(gas), arsenic, etc, there really is no “safe” level, just acceptable concentrations in various settings. Reducing any real pollutant to undetectable levels would be considered ideal in the abstract. But also very difficult in practice at reasonable costs in most settings. Thus the EPA sets minimum levels to be safe for humans, animals or plants

      But If you ever find yourself confronted by someone who indeed believes CO2 is “carbon pollution”, just ask them, “What would the effect of reducing CO2 “pollution” concentration to near zero? Afterall, that is what is the goal with any real pollutant..”

      If they say, “We need to eliminate just man’s release of CO2”, then ask them to please stop breathing.

  11. Isn’t a snag for this theory that total column water vapor plus specific and relative humidity have all fallen over the last few decades (except for specific humidity near the surface, about flat), i.e. the opposite of predictions by climate models?

    This data is apparently challengable (isn’t everything in the climate domain). Yet it suggests that via air transport, industry, and all other human effects combined including CO2 emissions, we’re not likely to be making a major impact on water vapour (or a downswing through natural variability is absorbing this impact).

    • Thanks, I did look at this site and was able to make some estimates. The highest data band given is 3-6 km it has only 3-4 mm of water in that 3 km thick column. The area where planes fly is up about 10 km where there is probably even less water. I calculated the water production from jet fuel consumed (you get 234 g of water for every 150 g of fuel) and it is about 0.7 mm per year (over the earth surface). Also note the site warns us that the downward shift in data over time might be due to changes processing.

  12. Never mind the water vapour as a GHG, the actual solid water in contrails will have an albedo effect and will reduce night time radiation, and the image at the top shows that the albedo variation at least is huge.
    Cloud we know reduces daytime temps but increases night time temps. What this means overall is something I dont have a handle on..

    Its ironic that this was first mooted as a spoof theory, a few years back…but the actual curve match is startling..

  13. I’m suprised that the greens haven’t been campaigning for aircraft to only fly at altitudes where the right amount of contrail is formed. Presumably they’re waiting until someone works out whether its impact would be positive or negative, one of those bits of unsettled settled science.
    By the way, I think you meant wreak its vengeance not wreck.

    • Well if you fly ling haul at night, that’s a net temp rise, and if you fly by day, its a net temp fall., So a perfect climate control knob..except it takes a lot of fossil fuel to use it!

  14. Contrails are more visually impressive, but not the only source. Burning natural gas produces two water molecules for every methane. Oxidation of hydrocarbons generally produces water molecules. I don’t know how long the water stays in gas phase, but there is increasing use of natural gas world-wide. Wouldn’t it be ironic if burning coal produces the least amount of greenhouse gas warming?

    • No one has mentioned the relative amount of man-made increase in humidity due to irrigation – from increasing water surface area behind dammed rivers, reservoirs – to channeling irrigation ditches to spread waters to fields – to large scale sprinkling systems, and bringing up the water from aquifers. How does this estimated amount compare to the increase in humidity due to the burning of all fossil fuels?

  15. Ok, then what explains the warm period in the earlier part of the 1900s? AGW doesn’t explain it, this wouldn’t appear to either. Relevant imo because it is similar to the current warm period. Even if it is a factor I personally doubt we can quantify its effect fully until we better understand more of the factors driving climate, and if we cant explain semi recent eras we have decent data for such as the early 1900s we I expect have a long way to go in that regard.

  16. Unless I missed it, where is the comparison for the amount of water vapor created by aviation to the total amount of water vapor in the entire atmosphere?

    • This article is junk science.

      I could find correlation with CO2 rise and the appearance and growth of my ear hairs over the past 3 decades. But there is zero causal linkage.

      Similarly, I could find correlation with the appearance of my gray hair and global warming since 1980. My gray hair seems to have reached a plateau in the past 10 years like temperatures. Again, it would be a junk correlation.

  17. But in 20 years time all airliners will be battery/electric powered, so any water vapour created in the charging process will be emitted at ground level.

    /sarc off

  18. I’m sure there’s a correlation to the consumption of fairy cakes to global temperature somewhere!
    Water vapour is no more plausible for observed surface temperatures than CO2 is.
    Such a shame that the writers for this web page are just as clueless as the alarmists when it comes to believing in a fictitious Greenhouse Effect.
    You all do a great job in pointing out satellite temperature data and absurd alarmist claims, but until you accept that gravity, atmospheric mass and distance to the sun are the only relevant criteria for mean temperatures, you will keep embarrassing yourselves.

    • More like a “water foot print” . Made by somebody who walks on water. Wait a minute ….that’s a differnt fairy tail.

  19. This is a new hype to stop nuclear technology when it turned out that CO2 is not the real threat.

  20. Anthony, you shouldn’t tease Bill McKibben so. Just know that you have a broader understanding of this issue and reality will prove you correct in time, then you can be the bigger person and forgive/forget.

  21. Skeptic logic.

    1. It got warm before without c02 increasing (think MWP) therefore it cant be c02.

    hows that logic hold up?
    looking at 1900 to 1940 I see it getting warmer, but there are no jets in that period.
    Therefore, applying #1, jets today cant be the cause of warming.

    • 2.From 1940 to 1976 it got colder (before data massage) and jet travel increased a LOT.

      3. From 1976 to 1997 it warmed a lot and jet travel went crazy.

      4. From 1997 to present warming is barely crawling and jet travel went viral.

      Skeptic logic: particularly when 1. above is included, ain’t much correlation.

    • Warmist “logic”.
      1. We don’t know what else could have caused the slight warming late last century, therefore it must be CO2.

      How’s that logic holding up?
      Jets or no jets.

    • Mr. Mosher,
      I’m sure you had some kind of convincing argument buried in that comment, but what was it ?
      Other than snark.

  22. Jets fly nearer TOA where most of the energy is being radiated to space rather than to the surface (lots of atmosphere between surface and TOA). Look at the global distribution of those flights. The obvious difference between SH and NH and all the great circle flights that traverse the Arctic circle. Could this help explain NH CO2 concentrations being greater than SH concentrations and Artic CO2 concentrations being the highest?

  23. “The right answer is not known, more real science is needed with all hypotheses on the table.”
    The sarcastic and cynical side of me says that “climate scientists” will not be performing any of that real science needed. In other words, “climate scientists” such as M. Mann need not apply.

    • Ummmmmmm no…..The contrails would act like clouds and DEFLECT the sunlight back into space, as was seen on the days following got hotter without the contrails.

      [“Reflect” instead? .mod]

    • One factor that is not quantified yet is the influence of cosmic rays on CCNs and aerosols at the TOA. Might jet engines be mixing existing particulates with water vapor (which enhances nucleation of the ice particles in the turbulence of the contrail) and getting an energy boost to form CCNs from TOA radiation levels?

  24. Correlation doesn’t imply causality. But air traffic does have some effect on temperatures, although it is very hard to describe in exact values: It helps with high clouds formation, although it is crucial that good conditions for their development already exist: for example, in high pressure air fields, contrails vane in a few minutes time, while on edges of atmospheric fronts, they can last for hours.

  25. “Water vapor is a more effective greenhouse gas than carbon dioxide by virtue of its asymmetric molecular structure that allows more vibration modes”

    This is the second time I’ve seen this claim lately. I am sorry to be a pedantic nit-picker here, as it doesn’t really affect the larger point, but this is worth getting right.

    CO2 has four vibrational modes, water has three. Two of CO2’s modes occur together, so in practice three modes could be observed for each. Of those three, it’s true that the symmetric stretch of CO2 cannot absorb IR energy, whereas the symmetric stretch of water can, because CO2 is linear and water is not.

    But it is not the case that water is a more effective greenhouse gas because it has more vibrational modes. In any case, I don’t believe you can compare one absorber to another by saying, This one has more IR-active modes, so it’s a better absorber. SF6 has only one IR-active mode, and pound for pound it’s a much more powerful greenhouse gas. We just don’t worry as much about it because we’re not releasing gigatons of it.

    • “Of those three, it’s true that the symmetric stretch of CO2 cannot absorb IR energy, whereas the symmetric stretch of water can, because CO2 is linear and water is not.”

      JPS, could you please explain about the above sentence, what the result is in regard to the greenhouse effect of respectively CO2 and H2O?

      • Sorry to be unclear. What I meant is that you just can’t translate these qualitative fundamentals to a quantitative comparison of greenhouse effectiveness. CO2 has four vibrational modes but only two IR-active modes. Water has three, all of them IR-active. What you can’t then conclude is that 3>2, so water is more effective, because this skips over how broad these absorbances are with respect to wavelength, how intensely a given concentration absorbs, etc.

        Googling around for images of the IR spectrum of CO2 versus water vapor, I found this earlier WUWT post, which conveys several of the factors at work better than I have.

    • Dear JPS
      Thank you for the correction. I was paraphrasing (possibly inaccurately) something my father-in-law had told me. He was head of the gas spectrometry lab at the UK Atomic Energy in the 1950/60s and did a lot of work on CO2. Interestingly way back in 2000 he was skeptical about CO2 role because it was such a good blocker of IR that he felt it would fully saturate in about 10m at 300ppm. He has softened his opinion since due to the weaker sidebands.

  26. Sorry. Nit-pick karma caught up to me. SF6 has three IR-active modes, not one, but they are degenerate, and therefore absorb the same energy.

  27. Hmmmm. One airplane engine releasing water vapor at around 500 mph, just by definition will release 10 times the water vapor than a smokestake whose emissions exit the smokestack at 50 mph (assuming the same concentration of course). So if one airplane engine has 10 times the emissions of a smokestack, and most planes have two engines, and water vapor has 5 times (ish) the greenhouse gas potency of carbon dioxide, this could be significant. It should be studied (although we know it hasn’t and won’t).

    • Bernie, ” (assuming the same concentration of course)”

      This is where your calculations fall short. You left out cross sectional area of the exhaust stream, for starters. Even if jet engine exhaust and electricity generation plant smoke stacks had the same concentration of water vapor, a smokestack has much more than ten times the cross sectional area of the tail pipe of a jet engine.

      Secondly, because a jet flies at around 500 mph doesn’t mean the engines are exhausting gas at around 500 mph.

      Evaluating water vapor emitted into the atmosphere by judging exhaust speed is doing it the hard way. Better to work from fuel consumed.


      • I think by definition the exhaust gases have to be doing 500mph and probably a little better. That said, totally agree that you have to go to fuel consumption if you want to compare. The engines get throttled back at altitude so you probably spew as much water on the way up as the rest of the trip.

      • The exhaust leaves the engine much faster than the airplane goes forward. Think in terms of balancing forces (F=M*V^2). Why do you think they call it a Jet? The jet out the rear is also pushing a lot of air that the “jet” is dragging with it. When it is supersonic it drags a sound wave with a good bit of force.

      • The plane is doing 500mph going east
        The motion is caused by the reaction of force (Newton)
        In the perfect world reaction = force
        So is the exhaust gas going west @ 500mph, meaning its coming out the back @1,000mph
        Or is the exhaust gas staying where it is & just the plane moving
        Or is the exhaust gas going west @ ~250mph whilst the plane is doing 500mph going east.

        Another teaser
        Car at 50mph; How fast are the wheels going ???

      • Your brain teaser can’t be answered without more info.

        == details
        For a plane in level flight, there is no acceleration so no net force is needed to keep it moving forward.

        That means a satellite in orbit doesn’t need any engine force at all to have constant horizontal speed. (vertical is more complicated).

        A plane has drag from the atmosphere. The only force the engines have to overcome in level flight is the drag. Since you didn’t specify the drag, you can’t even start to calculate anything about the thrust needed by throwing air out the back of the engine. I do agree it has to be moving the opposite direction of the plane or it wouldn’t provide any thrust at all. ie. if the plane is going west, the air thrown out the back of the plane is going east.

        3 notes:
        – In the early days of jets some of them carried water. they injected the water into the engines so there would be more mass being thrown out of the engines and thus more thrust. That was needed because pure jet engines don’t work well at low speeds. There simply isn’t enough air going through the engines during the takeoff roll for a pure jet engine to lift a heavy airliner / freighter.

        – Most airliners today are not pure jets (maybe none of them are pure jets). They’re turbofans ( The jet is used primarily to get the power to spin the fan which is enclosed in the outer duct. Most of the thrust comes from the fans pushing air backwards just like a propeller does.

        – There is less drag at higher altitudes which is why airplanes tend to have the best fuel economy at high altitude.

    • “will release 10 times the water vapor than a smokestake whose emissions exit the smokestack at 50 mph”

      This is not true. An airplane engine running stationary on the ground emitts the same water as the engine running at the same rate flying through the air. I cannot tell if this comment is meant to be a joke.

  28. When you are on top of a very big hill (i.e. a maximum), it can look very flat (hiatus). We will only be able to tell if it was a pause or a maximum when it will start to deviate from the present level.

    • …WTF….That makes no sense, Unless you are too delusional to understand that you are on top of a HILL !!!

  29. If you plot the relative increase in human population since 1960 against the pro-rata increase in atmospheric CO2, you get a near perfect straight line. So the answer to the AGW “problem” is simple: apply the ULTIMATE FINAL SOLUTION, starting with major “polluters”, such as Charlie Windsor and Al Gore! I feel sure that these Imams of AGW would be prepered to make the ultimate sacrifice for mankind, thus preserving the lives of ~30,000 poverty stricken Africans.

  30. How does atmospheric water vapour correlate with total area of equatorial/global forest cover?

    The water cycle from rainfall to river flow to ocean evaporation to rainfall is surely affected by the water absorption capacity of the forests and their ability to delay rainfall’s entry into the river system?

    Just wonder if anyone’s dared to plot any data of that kind ever?

  31. But, but… couldn’t one do exactly the same study with cows? Temperature of planet tracking them to fairly good R² correlation? Or to bananas. Or to dental implants. Or to computer memory per capita?

    This one must fall under the “correlation is not necessarily causation” department. Tho’ it is intriguing, especially given the partial world-wide shutdown of commercial aviation following 9/11 for a few days, and the measured increase in ground temperatures over the U.S. in turn. Or was it decrease?

    Obviously, we can NOT get away with emitting soots, dusts, water vapor, NO and N₂O₂ into the low-turn-over-rate stratosphere endlessly. It will change ‘things’. But we also have to be on guard for correlation theories that aren’t actually related to causation.


  32. “Water vapor is a more effective greenhouse gas than carbon dioxide”

    Yes, this is true, but you can not consider the GHG effect without considering the end to end effect of evaporation. The end to end effect is evident by Hurricanes which leave a trail of cold water in their wake, indicating net negative feedback. All weather is basically driven by a heat engine using water as the refrigerant where a Hurricane is a localized, more efficient version of this engine. The second law tells us that a heat engine can not warm its source of heat, which in the case of weather, is the surface. None the less, water vapor does contribute to warming, but this effect seems to be saturated and incremental water vapor actually results in cooling!

  33. Saying that water vapor cannot be modeled because of it’s short half life is a total cop out. Water vapor concentration is what it is at any moment regardless of turnover. Its GHE over any given area changes by the second because it is chaotic and that’s the real reason it cannot be modeled. It causes it’s own changes in concentration and therefore its net GHE varies from one place to another via things like its convective force as a vapor, or its albedo when it condenses or it just disappears when it precipitates. A very high concentration of WV over half a given area plus a very low concentration for the other half provide far less GHE than the average concentration of the two taken together over the whole area but that’s what modelers assume because they cannot model the former condition – and that’s why they are wrong. They need to model this –

    If there was an actual model for water vapor used to predict climate we would have accurate weather forecasts 10 years into the future. But the alarmists don’t want accuracy, they only want to keep collecting their pay checks so admitting that water vapor is firmly in control of our climate, (let alone actually trying to model it), is just something they will never dare to do, their taxpayer subsidized careers depend on blaming CO2.

  34. Don Spencer, a little arithmetic would have informed: 5mbbls/yr is insignificant, equivalent to 700,000t. Let’s say persistence in the atmosphere is 10yrs, then ~7million tonnes. The atmosphere according to USGS/NOAA contains 13,000Gt of water vapor on average (13,000 cubic km), so the amount added in 10 yrs represents 7/13,000,000,000,000 ~ 5 x 10^-13 or 0.00000000005% of the total.

    Moreover, anywhere the atmosphere has 100% relative humidity (raining, snowing or incipience) added water would be precipitated out making for even less than 7million tonnes. We get a heck of a lot more from the burning of fuels, even if it were all hydrogen and it, too, is of little significance. The sun-earth system dwarfs everything and the raining out effect would similarly reduce this larger mass source of human w.v. addition.

    I agree also with other commenters who have pointed out that in burning carbonaceous fuels, water vapour is the larger GHG emission – both in direct burning and the exhaust gas from steam turbines in electricity generation. This also goes for biomass, corn or whatever fuel you like. It is my observation over the decade of looking at the CAGW nonsense that simple arithmetic reveals the insignificance of every worse-than-we-thought fantasy produced by the clime syndicate (thanks to Mark Steyn for the term). There never has been a prediction or, more wishy washy, ‘projection’ of disaster that has ever come anywhere near marginally true over a few centuries of such doomster products.

    This truism I’ve distilled into an AXIOM: that mankind can do no lasting harm to the planet. At worst, only localized small areas can be harmed and this is relatively quickly erased by time. Not to minimize the horror of the atomic bombing of Hiroshima, radiation fell quickly to background levels within a year. Hiroshima today is a vibrant and thriving city. The Chernobyl ‘disaster’ was supposed to sterilize enormous territory in central Europe and produce a death toll of thousands (25,000 if I recall correctly) ~ some 35 apparently died and yes we had some hundreds sick. The ‘no go’ exclusion zone set up has become a vibrant game park, Europe’s Serengeti. Oh, Google will serve up a menu of horrific mutations and 100s of thousands of years of consequences and the truthbenders have flooded the internet with green slime. There were a certain percentage of deformed animals resulted but guess what? They were quickly eaten by predators and the unbelievable variety of animals and their populations should be considered one of the wonders of the world (but you can be sure it won’t be):

    “Actually, according to Mycio and photographer and field biologist Sergey Gaschak, the animals are thriving. …Communal farms turned to wetlands and forests, and the animals came back. The area is now the largest, if unintentional, wildlife sanctuary in Europe.

    Gaschak has been photographing animals near Chernobyl since 1995. He uses camera traps with motion detectors to capture some of the animals, but he sees and photographs plenty of them in person: lynx, otters, eagle owls, Przewalski’s horses, several species of bats, and footprints of brown bears….”

    Here’s George Carlin’s take on the harm man is doing to the planet:

  35. 5 million barrels of jet fuel per day = 28 cubic feet/day
    Niagara Falls approximate average flow rate = 4 million cubic feet/min = 5800million ft^3/day or = 1,030 million barrels/day.
    Niagara Falls was once water vapour but comprises only a tiny part of the global water cycle

  36. You might also see a correlation between jet fuel consumption and temperature because so many temperature measurements are done at airports.

  37. “The right answer is not known, more real science is needed with all hypotheses on the table.” I agree with that bit, especially in regard to the lunatic schemes of the Warmistas to relegate fossil fuels and advance ‘Green’ energy at great cost and no benefit.

  38. My airconditioner sucks water vapour from the atmosphere, at the cost of the production of a small amount of CO2 and heat. Does the water vapour extraction benefit cancel the CO2 and heat production cost?

  39. Next time you see a liberal on the street holding their silly signs about the dreaded CO2 caused Glo.Bull Warming, ask them what percentage of the atmosphere is made up of CO2.. I have asked approximately 160 liberals and 97% think the answer is 40% ! Nuff said…

  40. “Thousands of large flying machines have been circling the earth day and night releasing millions of tons of water vapor into the upper atmosphere. ”

    We are beset by aliens trying to drown us!

    We’re doomed!

  41. “…vastly increase our water vapor output”

    Wouldn’t a “hydrogen economy” based on nuclear energy cycle 2(H2O) into 2H2 and O2 which would then be converted back into H2O in fuel cells? Wouldn’t evaporation of the exhaust actually provide some cooling effect?

    Meanwhile, however, nuclear reactors and the electrical and electronic devices they power would still be warming the globe. And there would still be an issue with high-flying aircraft:

    Perhaps it would be better to wait until the seas rise enough to bypass hydrogen power and use compact nuclear reactors to directly power personal speedboats.

  42. Well, I would at least grant that those who fly are responsible for much of the man-made CO2 emissions. But that’s all I’ll grant, lol. There was a day when everyone had a fire burning at home. I’m sure that created a lot of CO2 emissions as well – in addition to real pollution in the form of smoke.

    • Not all “carbon emissions” are created equal. Within the carbonophobic Warmist ideology, burning wood is fine, because it is actually just recycling CO2 which is already in our atmosphere. And smoke, or indeed any real environmental consequence is but a pittance of a price to pay in the quest to rid ourselves of the enormous “carbon” ogre.

      • As to CO2, it might be worse in the short run, but in the course of decades, it is better. In particular, in Georgia (USA) trees are a crop and the “farmers” grow them because they can make money doing so.

        Pine “farmers” here leave pines in the ground 30 years before they harvest them. For each tree harvested in Georgia, 2 are supposed to be planted.

        “And because of those practices we actually have more trees today than we did 50 years ago,” said Burnett.

        If that actually happens, then at the end of 30 years you have 2x the CO2 in living trees than you did in the one cut down and burned. Georgia is the source of lots of lumber and paper made from pines, so we have millions of acres in forest.

        Per it is roughly 25 million acres in forest and 92% of that is privately owned.

        My understanding is that a lot of that 92% is trees being grown commercially. That means “conservation” of that wood (by recycling of paper or use of different building materials) will actually cause less acres to be managed as commercial forests. Thus in turn, recycling paper actually causes less trees to be needed and thus less trees allowed to grow.

        If those trees are harvested for burning in commercial plants, then I expect even more trees will be planted to replace them. Remember, here they are a crop just like corn or wheat. At least in Georgia, if you want more trees to grow then you need to come up with a commercial use for them.

        In this area of the country, people recycling paper are actually just reducing the number of trees that are allowed to grow.

        I don’t know how that works in rest of the country/world.

  43. “However since WWII humans have been conducting a great atmospheric seeding experiment. Thousands of large flying machines have been circling the earth day and night releasing millions of tons of water vapor into the upper atmosphere. ”

    I choked, literally, when I read that in the OP…absolute perfection!

  44. Perhaps the consumption indicates the number of aircraft movements? So the number of aircraft taking off and blasting the temperature sensors at the airport monitoring systems has increased, this affects the global temperature data and hence the correlation between the fuel consumption and global warming which would be more prominent since the increased prosperity since the 1970s with plenty of cheap flight packages.

  45. Interesting hypothesis, with other good evidence to back it up- changes in daily cloud cover depending on insolation and humidity, various ice condensation regimes in the stratosphere, etc.,
    The NASA image is another story. 4-5 major airports in southcentral Georgia with flights heading straight north? Half a dozen island pairs within 100 mi or so of the coast with jetports? Four jetports in northern near Gainesvilee Florida with planes flying straight north to the boarder? Smugglers? Not to nitpick, but I am, simply presenting the pic with “jet contrails” as the explanation is misleading.

    • You might want to take a look at a globe. Pretty much due north from Florida / Georgia is Detroit. Chicago is slightly to the west of that, so more north, north, northwest. Those North/South contrails could easily be planes flying from either of the cities to one of the big airports in Florida. Contrails don’t necessarily end at an airport.

  46. Thanks for the comments all good reading. Firstly, carbon dioxide and water vapour are greenhouse gases and fortunately we have them to thank for the 30 deg C contribution they make to our climate. Secondly I wholly agree that climate changes has been happening forever and our sun is probably the main factor. Dr. Nicola Scafetta (Duke University) presented an interesting paper looking at 20 and 60 year natural harmonics in the climate. However their analysis after natural cycles were factored still suggested an rise in temperature following WWII and attributed it to man-made causes. Finally, please don’t confuse the contrails with water vapour – if you can see it it ain’t water vapour. It is true the contrails should increase the global albedo and be a cooling source but there still could be a lot of free water vapour that has not condensed. Due to the sparse atmosphere the half-life of water vapour (before phase change) could be a lot longer than near the surface. Dr. Susan Soloman (NOAA) in 2010 looked at the upper atmosphere water vapour and concluded that the recent lower concentrations could be responsible for the hiatus – not too different than what I’m suggesting here. To reiterate I don’t know the answer it is, it is probably a bunch of things, some natural and some man-made.

    • Don Spencer,

      You refer to NOAA’s Dr. Susan Soloman, who looked at the upper atmosphere water vapour and concluded that the recent lower concentrations could be responsible for the hiatus.

      She can’t be correct. Well, I suppose she could be right — if we accept that for almost 20 years now, declining water vapor has exactly matched global warming. Her claim is that global warming would be continuing, except for her presumption that changing humidity has precisely offset AGW, to the point that global T has remained unchanging. That’s absurd.

      Sooner or later ‘explanations’ like Dr. Solomon’s get so preposterous and unlikely, that the only reasonable conclusion is that she will “Say Anything”, rather than admit what Occam’s Razor is telling us: AGW is so tiny that it has no observable effect.

  47. This reminds me of the exercise we did in a social science degree on correlation not being cause and effect where we had to find the stupidest correlation. The winner was “aids is caused by driving Toyota landcruisers” where it had near perfect correlation between sales of the vehicles in the area used and the rise in aids in the area.

  48. I havent had the time to read all the comments so maybe someone else mentioned this, but when I read the headline I thought it might mean that, since so many thermometers are now located at airports, then the rise in “Global Temperature” (whatever that might mean) is due to the jet engines heating the thermometers. Therefore the more jet fuel is used, the hotter it gets.

    • I agree that the title is misleading, because it relates to jet fuel, not jet exhaust, and jets don’t consume water vapor.

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