How carbon dioxide controls earth’s temperature

NASA’s Lacis: “There is no viable alternative to counteract global warming except through direct human effort to reduce the atmospheric CO2 level.”

A study by GISS climate scientists recently published in the journal Science shows that atmospheric CO2 operates as a thermostat to control the temperature of Earth….

CO2 is the key atmospheric gas that exerts principal control (80% of the non-condensing GHG forcing) over the strength of the terrestrial greenhouse effect. Water vapor and clouds are fast-acting feedback effects, and as such, they are controlled by the radiative forcing supplied by the non-condensing GHGs….

There is no viable alternative to counteract global warming except through direct human effort to reduce the atmospheric CO2 level.’s Goddard Institute for Space Studies has posted three articles on their website explaining two important new studies, “Atmospheric CO2: Principal control knob governing Earth’s temperature” (subs. req’d) in Science by Andrew Lacis et al. and “The attribution of the present-day total greenhouse effect” (subs. req’d) in JGR by Gavin Schmidt et al.  Together they make a terrific tutorial on the critical role human-caused CO2 plays in climate change.

Schmidt is best known as a key contributor to the must-read blog, Real Climate.  Lacis may be best known as the NASA climatologist whose 2005 critique of the IPCC Fourth Assessment draft — “There is no scientific merit to be found in the Executive Summary” — was embraced by the anti-science disinformers until it was revealed he thought the IPCC consensus was in fact some watered down, least-common denominator piece of wishy-washiness that understates our scientific understanding, which it is (see “Disputing the ‘consensus’ on global warming“).

It may be obvious to CP readers and all those who follow the science, but the core conclusion of the Science article bears repeating again and again by all of us who communicate on global warming:

Ample physical evidence shows that carbon dioxide (CO2) is the single most important climate-relevant greenhouse gas in Earth’s atmosphere. This is because CO2, like ozone, N2O, CH4, and chlorofluorocarbons, does not condense and precipitate from the atmosphere at current climate temperatures, whereas water vapor can and does. Noncondensing greenhouse gases, which account for 25% of the total terrestrial greenhouse effect, thus serve to provide the stable temperature structure that sustains the current levels of atmospheric water vapor and clouds via feedback processes that account for the remaining 75% of the greenhouse effect. Without the radiative forcing supplied by CO2 and the other noncondensing greenhouse gases, the terrestrial greenhouse would collapse, plunging the global climate into an icebound Earth state.

Indeed, absent greenhouse gases, the planet would be about 60°F colder.

Here is NASA’s Research News piece, “How Carbon Dioxide Controls Earth’s Temperature” summarizing the two studies:

Water vapor and clouds are the major contributors to Earth’s greenhouse effect, but a new atmosphere-ocean climate modeling study shows that the planet’s temperature ultimately depends on the atmospheric level of carbon dioxide.

The study, conducted by Andrew Lacis and colleagues at NASA’s Goddard Institute for Space Studies (GISS) in New York, examined the nature of Earth’s greenhouse effect and clarified the role that greenhouse gases and clouds play in absorbing outgoing infrared radiation. Notably, the team identified non-condensing greenhouse gases “” such as carbon dioxide, methane, nitrous oxide, ozone, and chlorofluorocarbons “” as providing the core support for the terrestrial greenhouse effect.

Without non-condensing greenhouse gases, water vapor and clouds would be unable to provide the feedback mechanisms that amplify the greenhouse effect. The study’s results will be published Friday, Oct. 15, in Science.

A companion study led by GISS co-author Gavin Schmidt that has been accepted for publication in the Journal of Geophysical Research shows that carbon dioxide accounts for about 20 percent of the greenhouse effect, water vapor and clouds together account for 75 percent, and minor gases and aerosols make up the remaining five percent. However, it is the 25 percent non-condensing greenhouse gas component, which includes carbon dioxide, that is the key factor in sustaining Earth’s greenhouse effect. By this accounting, carbon dioxide is responsible for 80 percent of the radiative forcing that sustains the Earth’s greenhouse effect.

The climate forcing experiment described in Science was simple in design and concept “” all of the non-condensing greenhouse gases and aerosols were zeroed out, and the global climate model was run forward in time to see what would happen to the greenhouse effect.
Various atmospheric components differ in their contributions to the greenhouse effect, some through feedbacks and some through forcings. Without carbon dioxide and other non-condensing greenhouse gases, water vapor and clouds would be unable to provide the feedback mechanisms that amplify the greenhouse effect.
Without the sustaining support by the non-condensing greenhouse gases, Earth’s greenhouse effect collapsed as water vapor quickly precipitated from the atmosphere, plunging the model Earth into an icebound state “” a clear demonstration that water vapor, although contributing 50 percent of the total greenhouse warming, acts as a feedback process, and as such, cannot by itself uphold the Earth’s greenhouse effect.

“Our climate modeling simulation should be viewed as an experiment in atmospheric physics, illustrating a cause and effect problem which allowed us to gain a better understanding of the working mechanics of Earth’s greenhouse effect, and enabled us to demonstrate the direct relationship that exists between rising atmospheric carbon dioxide and rising global temperature,” Lacis said.

The study ties in to the geologic record in which carbon dioxide levels have oscillated between approximately 180 parts per million during ice ages, and about 280 parts per million during warmer interglacial periods. To provide perspective to the nearly 1°C (1.8°F) increase in global temperature over the past century, it is estimated that the global mean temperature difference between the extremes of the ice age and interglacial periods is only about 5°C (9°F).

“When carbon dioxide increases, more water vapor returns to the atmosphere. This is what helped to melt the glaciers that once covered New York City,” said co-author David Rind, of NASA’s Goddard Institute for Space Studies. “Today we are in uncharted territory as carbon dioxide approaches 390 parts per million in what has been referred to as the ‘superinterglacial.'”

“The bottom line is that atmospheric carbon dioxide acts as a thermostat in regulating the temperature of Earth,” Lacis said. “The Intergovernmental Panel on Climate Change has fully documented the fact that industrial activity is responsible for the rapidly increasing levels of atmospheric carbon dioxide and other greenhouse gases. It is not surprising then that global warming can be linked directly to the observed increase in atmospheric carbon dioxide and to human industrial activity in general.”

Here is Lacis’s explanatory Science Brief, “The Thermostat that Controls Earth’s Temperature“:

A study by GISS climate scientists recently published in the journal Science shows that atmospheric CO2 operates as a thermostat to control the temperature of Earth.

There is a close analogy to be drawn between the way an ordinary thermostat maintains the temperature of a house, and the way that atmospheric carbon dioxide (and the other minor non-condensing greenhouse gases) control the global temperature of Earth. The ordinary thermostat produces no heat of its own. Its role is to switch the furnace on and off, depending on whether the house temperature is lower or higher than the thermostat setting. If we were to carefully monitor the temperature of the house, we would see that the temperature does not stay constant at the set value, but rather exhibits a “natural variability” as the house temperature slips below the set value and then overshoots the mark with a time constant of minutes to tens of minutes, because of the thermal inertia of the house and because heating by the furnace (when it is on) is more powerful than the steady heat loss to the outdoors. If the thermostat is suddenly turned to a very high setting, the temperature will begin to rise at a rate dictated by the inertia of the house and strength of the furnace. Turning the thermostat back to normal will stop the heating.

Atmospheric carbon dioxide performs a role similar to that of the house thermostat in setting the equilibrium temperature of the Earth. It differs from the house thermostat in that carbon dioxide itself is a potent greenhouse gas (GHG) warming the ground surface by means of the greenhouse effect. It is this sustained warming that enables water vapor and clouds to maintain their atmospheric distributions as the so-called feedback effects that amplify the initial warming provided by the non-condensing GHGs, and in the process, account for the bulk of the total terrestrial greenhouse effect. Since the radiative effects associated with the buildup of water vapor to near-saturation levels and the subsequent condensation into clouds are far stronger than the equilibrium level of radiative forcing by the non-condensing GHGs, this results in large local fluctuations in temperature about the global equilibrium value. Together with the similar non-linear responses involving the ocean heat capacity, the net effect is the “natural variability” that the climate system exhibits regionally, and on inter-annual and decadal timescales, whether the global equilibrium temperature of the Earth is being kept fixed, or is being forced to re-adjust in response to changes in the level of atmospheric GHGs.

Radiative modeling analyses of the terrestrial greenhouse structure described in a parallel study in the Journal of Geophysical Research (Schmidt et al., 2010) found that water vapor accounts for about 50% of the Earth’s greenhouse effect, with clouds contributing 25%, carbon dioxide 20%, and the minor greenhouse gases (GHGs) and aerosols accounting for the remaining 5%, as shown in Fig. 1.

Figure 1. Attribution of individual atmospheric component contributions to the terrestrial greenhouse effect, separated into feedback and forcing categories. Dotted and dashed lines depict the fractional response for single-addition and single-subtraction of individual gases to either an empty or full-component reference atmosphere, respectively. Solid black lines are the scaled averages of the dashed and dotted line fractional response results. The sum of the fractional responses must add up to the total greenhouse effect. The reference model atmosphere is for 1980 conditions.

Thus, while the non-condensing greenhouse gases account for only 25% of the total greenhouse effect, it is these non-condensing GHGs that actually control the strength of the terrestrial greenhouse effect since the water vapor and cloud feedback contributions are not self-sustaining and as such, only provide amplification. Because carbon dioxide accounts for 80% of the non-condensing GHG forcing in the current climate atmosphere, atmospheric carbon dioxide therefore qualifies as the principal control knob that governs the temperature of Earth.The numerical climate experiment described in Fig. 2. demonstrates the fundamental radiative forcing role of the non-condensing GHGs, and the feedback (only) role of water vapor and clouds. This climate modeling experiment was performed using the GISS ModelE general circulation coupled atmosphere-ocean climate model by zeroing out all of the non-condensing greenhouse gases. Doing this removed the radiative forcing that sustains the temperature support for water vapor and cloud feedbacks, causing rapid condensation and precipitation of water vapor from the atmosphere, collapsing the terrestrial greenhouse effect, and plunging the Earth into an icebound state.

Figure 2. Time evolution of global surface temperature, top-of-atmosphere (TOA) net flux, column water vapor, planetary albedo, sea ice cover, and cloud cover, after zeroing out all the non-condensing greenhouse gases. The model used in the experiment is the GISS 2°—2.5° AR5 version of ModelE with the climatological (Q-flux) ocean energy transport and the 250 m mixed layer depth. The model initial conditions are for a pre-industrial atmosphere. Surface temperature and TOA net flux utilize the left-hand scale.

The scope of the climate impact becomes apparent in just 10 years. During the first year alone, global mean surface temperature falls by 4.6 °C. After 50 years, the global temperature stands at -21 °C, a decrease by 34.8 °C. Atmospheric water vapor is at ~10% of the control climate value (22.6 to 2.2 mm). Global cloud cover increases from its 58% control value to more than 75%; the global sea ice fraction goes from 4.6% to 46.7%, causing the planetary albedo of Earth to increase from ~29% to 41.8%. This has the effect to reduce the absorbed solar energy to further exacerbate the global cooling. After 50 years, one third of the ocean surface still remains ice-free, even though the global surface temperature is colder than -21 °C. At tropical latitudes, incident solar radiation is enough to keep the ocean from freezing. While this thermal oasis within an otherwise icebound Earth appears to be stable, at least on the short timescale illustrated, further calculations with an interactive ocean are needed to verify the potential for long-term stability. The surface temperatures in Fig. 3 are only marginally warmer than 1 °C within the remaining low latitude heat island.

Figure 3. Zonally averaged annual-mean surface temperature change following the zeroing out of non-condensing greenhouse gases.

From the foregoing, it is clear that CO2 is the key atmospheric gas that exerts principal control (80% of the non-condensing GHG forcing) over the strength of the terrestrial greenhouse effect. Water vapor and clouds are fast-acting feedback effects, and as such, they are controlled by the radiative forcing supplied by the non-condensing GHGs.

The bottom line is that atmospheric carbon dioxide acts as a thermostat in regulating the temperature of Earth. The rapid increase in atmospheric carbon dioxide due to human industrial activity is therefore setting the course for continued global warming. Because of the large heat capacity of the climate system, the global surface temperature does not respond instantaneously to the sharp upturn of the carbon dioxide thermostat, which at this moment stands at 386.80 ppm compared to the normal interglacial maximum level of 280 ppm. Since humans are responsible for changing the level of atmospheric carbon dioxide, they then also have control over the global temperature of the Earth. Humans are at a difficult crossroad. Carbon dioxide is the lifeblood of civilization as we know it. It is also the direct cause fueling an impending climate disaster. There is no viable alternative to counteract global warming except through direct human effort to reduce the atmospheric CO2 level.

The basic physics for the present study is rooted in the high precision measurements documenting the rise of atmospheric carbon dioxide and other greenhouse gases as fully described in the IPCC AR4 report, and in the comprehensive HITRAN database (Rothman et al. 2009) of atmospheric absorption data. The radiative transfer calculations involve well-understood physics that is applied to the global energy balance of the Earth, which is maintained by radiative processes only, since the global net energy transports must equal zero. This demonstrates the nature of the terrestrial greenhouse effect as being sustained by the non-condensing GHGs, with magnification of the greenhouse effect by water vapor and cloud feedbacks, and leaves no doubt that increasing GHGs cause global warming.

For an excellent talk on the role of CO2, see In must-see AGU video, Richard Alley explains “The Biggest Control Knob: Carbon Dioxide in Earth’s Climate History.”

Here is Schmidt’s explanatory Science Brief, “Taking the Measure of the Greenhouse Effect“:

Most of us have heard that the greenhouse effect keeps the planet much warmer than it would be otherwise, and similarly we may have heard that increasing amounts of greenhouse gases are enhancing the natural greenhouse effect. But few of us appreciate what exactly it is in the atmosphere that makes the effect work and why small changes in trace gases such as carbon dioxide (CO2) might make a difference.

It has been understood since the 19th century that some gases absorb infrared radiation (IR) that is emitted by the planet, slowing the rate at which the planet can cool and warming the surface. These so-called greenhouse gases include carbon dioxide and water vapor, as well as ozone and methane among others. Note, however, that the bulk of the atmosphere is made up of nitrogen and oxygen molecules which don’t absorb IR at all. Less well appreciated is that clouds (made of ice particles and/or liquid water droplets) also absorb infrared radiation and contribute to the greenhouse effect, too. Clouds, of course, also interfere with incoming sunlight, reflecting it back out to space, making their net effect one of cooling, but their contribution to the greenhouse effect is important.

The size of the greenhouse effect is often estimated as being the difference between the actual global surface temperature and the temperature the planet would be without any atmospheric absorption, but with exactly the same planetary albedo, around 33°C. This is more of a “thought experiment” than an observable state, but it is a useful baseline. Another way of quantifying the effect is to look at the difference between the infrared radiation emitted at the surface of the Earth, and the amount that is emitted to space at the top of the atmosphere. In the absence of the greenhouse effect, this would be zero (in other words, no difference). In actuality the surface emits about 150 Watts per square meter (W/m2) more than goes out to space.

So of all the greenhouse substances in the atmosphere, which of them absorbs what? This is a more complicated issue than it might first appear because of the nature of the absorption and the complex distribution of absorbers both horizontally and vertically. Different substances absorb different frequencies of IR, and the different parts of the planet differ wildly in how much IR is being emitted (based as it is on surface temperature) and how much cloud and water vapor there is at that location (carbon dioxide is very well mixed). Indeed, some wavelengths of IR can be absorbed by both water vapor or clouds, or water vapor and CO2. This “spectral overlap” means that if you remove a substance, the change in how much IR is absorbed will be less than if you only had that substance in the air. Alternately, the impact of all the substances together is less than what you would get if you added up their individual components. This needs to be taken into account in any attribution of the greenhouse effect.

Line plot of outgoing spectral radiance at the top of Earth's atmosphere

Outgoing spectral radiance at the top of Earth’s atmosphere showing the absorption at specific frequencies and the principle absorber. For comparison, the red curve shows the flux from a classic “blackbody” at 294°K (‰ˆ31°C ‰ˆ 69.5°F). (View larger image)

We use the GISS model of radiative transfer through the global atmosphere to try and break down the attribution using realistic distributions of local temperature, water vapor and clouds. By removing each of the absorbers in turn and calculating the absorption for many different combinations, we can calculate all the overlaps and allocate the absorption fairly. We find that water vapor is the dominant substance “” responsible for about 50% of the absorption, with clouds responsible for about 25% “” and CO2 responsible for 20% of the effect. The remainder is made up with the other minor greenhouse gases, ozone and methane for instance, and a small amount from particles in the air (dust and other “aerosols”).

Given that CO2 has such a major role in the natural greenhouse effect, it makes intuitive sense that changes in its concentration because of human activities might significantly enhance the greenhouse effect. However, calculating the impact of a change in CO2 is very different from calculating the current role with respect to water vapor and clouds. This is because both of these other substances depend on temperatures and atmospheric circulation in ways that CO2 does not. For instance, as temperature rises, the maximum sustainable water vapor concentration increases by about 7% per degree Celsius. Clouds too depend on temperature, pressure, convection and water vapor amounts. So a change in CO2 that affects the greenhouse effect will also change the water vapor and the clouds. Thus, the total greenhouse effect after a change in CO2 needs to account for the consequent changes in the other components as well. If, for instance, CO2 concentrations are doubled, then the absorption would increase by 4 W/m2, but once the water vapor and clouds react, the absorption increases by almost 20 W/m2 “” demonstrating that (in the GISS climate model, at least) the “feedbacks” are amplifying the effects of the initial radiative forcing from CO2 alone. Past climate data suggests that this is what happens in the real world as well.

What happens when the trace greenhouse gases are removed? Because of the non-linear impacts of CO2 on absorption, the impact of removing the CO2 is approximately seven times as large as doubling it. If such an event were possible, it would lead to dramatic cooling, both directly and indirectly, as the water vapor and clouds would react. In model experiments where all the trace greenhouse gases are removed the planet cools to a near-Snowball Earth, some 35°C cooler than today, as water vapor levels decrease to 10% of current values, and planetary reflectivity increases (because of snow and clouds) to further cool the planet.

Despite being a trace gas, there is nothing trivial about the importance of CO2 for today, nor its role in shaping climate change in the future.

Global map of outgoing longwave radiation in September 2008

A satellite map of the outgoing longwave radiation emitted by Earth in September 2008 demonstrates not only geographical variations but also those caused by cloud presence. More heat escapes from areas just north and south of the equator, where the surface is warmer and there are fewer clouds. (Image: NASA/Earth Observatory/Robert Simmon from CERES data.)

For more on attribution, see “10 indicators of a human fingerprint on climate change.”

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39 Responses to How carbon dioxide controls earth’s temperature

  1. These really are key papers, along with which tells us how much co2 is too much. GISS has given us, over the years, all the information we need to understand our plight. It is beyond ironic that American government scientists have led the way, given the failure of the government to act. Joe, thanks for posting all this–an invaluable resource

  2. Lorien says:

    This is excellent and informative, especially useful for those of us who aren’t scientists. Thanks for posting this.

  3. Peter M says:

    I read this originally over at Science Daily a few days ago- its very straight forward about the major role C02 has always had in global temperatures.

    Hopefully the Denier crowd reads this- for what good it would do to dispel the myths they perpetuate.

  4. Mike Roddy says:

    I second Bill and Lorien. Copies should be sent to everyone in Congress and key media outlets, with extras for staff.

  5. Richard Brenne says:

    Later this week my partner Toby Dittrich and I are going to the California Science Teachers Conference to get them to teach just this kind of stuff to their kids.

    We can’t burn a coal train that would stretch from Anthro-Earth almost to the sun (my back of the envelope calculations – anyone care to research this more closely and comment, like on the front of an envelope?) without having an effect.

    That and the CO2 from oil was sequestered in Anthro-Earth’s crust for up to 450 million years before being taken out, burned and dumped into Anthro-Earth’s atmosphere mostly within 100 years for oil and 200 years for coal. And we’ve burned more in the last 20 years than all of human history combined before that.

    The effects include warming that might mean that Mt. Hood and many other mountains have less snow and ice total on them, including glaciers, than they’ve had for as much as 125,000 years. I was on the glaciers on the North side of Mt. Hood on Saturday looking at this, and the glaciers are shadows of the ones I knew when I started climbing and circumnavigating the mountain in 1971.

    So thanks to Gavin, Joe, Bill, Mike and others for all the work you do on this.

  6. Robert says:

    I hope everyone is taking due note that the thermostat does not work off “CO2 per unit of GDP”, “MPG of the average vehicle”, “the rate of increase in wind power”, or any number of other economic metrics.

    Th growth in atmospheric CO2 is directly related to the rate at which fossil fuel is burned globally. In the absence of a treaty, the ultimate peak atmospheric concentration will be proportional to total recoverable reserves (the rate of extraction being somewhat irrelevant).

    Because of these simple facts the world must focus on (a) progressively reducing extraction rates, and (b) leaving as much as possible in the ground.

  7. Hot Tropics says:

    Master of Climate

    Your combined articles on GHG’s and the effect on climate is good reading.As a person that tries to look for solutions, I am going to highlight the enormous opportunities for up and coming young people or professionals who are looking for a long lasting career.

    A reasonable percentage of global Gross Domestic Product – GDP, will need to be diverted sooner or later to climate change adaption and mitigation. We know that sea level rise will increase over time whether we like it or not. Our water supplies and agriculture will be affected by climate change, making food and water security paramount.

    Coastal communities will adapt by building sea defence infrastructure or by ensuring current buildings can withstand inundation and, if not, can they be made demountable, and transported away from the coast in time to come.

    All of these endeavours and many that are associated will require skilled professionals who can take the lead and make things happen. It will require world universities to have suitable courses to train people now and for the future to cope with the changes.

    Leading universities, are showing initiative with suitable courses, like these 3 along the east coast of Australia. They are offering post graduate courses like the Masters of Climate Change and the Masters of Climate Change Adaption. The Courses listed below are flexible and open to international students. Graduates could work anywhere for many decades to come. Some are either near the world heritage Great Barrier Reef or near clusters of coastal national parks. Scuba diving, surfing, rainforest exploration and a host of adventure activities are some of the benefits, but I guess we have to put up with it if we are to make the world a better place!

    Master of Climate Change;overview.html

    Master of Climate Change Adaptation

    Master of Development Practice

  8. Harrier says:

    Hot Tropics, I have a problem with the formulation “whether we like it or not.” On our current emissions path, sea level rise and all the other effects of climate change are unavoidable. But to speak of the effects of climate change as inevitable does not take into account our potential ability to remove carbon dioxide (and methane) from the atmosphere, thereby ‘turning down the thermostat’ and reversing global warming. There are several new technologies that show promise in this regard, along with several older solutions like biochar, and several more solutions that are being developed right now in laboratories.

  9. Tim says:


    Excellent post. You should consider augmenting your “Most Popular Posts” with a series of past (and future) that really are educational and enduring, entitled “Posts on the Fundamental Science of Global Warming” or something similar. It would be an excellent resource for teachers and internet debaters.

    On a related note, as long as the number of key papers were kept to a reasonably small number, who knows, maybe journals would allow you to give the public access to the top publications you’ve linked – you could always ask the AAAS and other publishers for a special consideration.

  10. Lewis C says:

    It’s a real pleasure to see these very complex issues clarified at long last, at least for those with some serious study of the problem. But for the mildly interested layman I’d guess that the information may well go straight past him owing to the somewhat arcane scientific concepts that the papers necessarily include.

    Ultimately I think we’ll need to accept that convincing the public of the urgency of action will be about politicians putting down the deniers and upholding the authority of science, rather than expecting scientists to do the politicians’ job of explaining the scientific priorities to the public.

    This is not in any way to knock these outstanding papers, but rather to hope that some highly skilled speechwriters one day get sent to spend time at places like NASA to work with scientists on an accurate but more accessible account of these matters.



  11. John Mason says:

    Great to have these up-to-date summaries all available on the same page, thanks.

    cheers – John

  12. Colorado Bob says:

    Been trying to follow Megi closely , Chevron has hiked the price of gasoline and kerosene in the Philippines.

  13. Dan B says:

    I’m in agreement with the recommendation to send this to everyone in congress, with a key addition: 1. Explain it in non-scientific terms. (my father was a research chemist) 2. Provide a vision of 21st Century economics (electric cars plugged into smart electrical grid “networking” clean green energy wherever it’s needed – or borrow Bill Clinton’s terrific messaging linking the Empire State Building’s “greening” to “green” construction jobs, one entire floor of people making “green” windows, and Nevada, a state that built too many offices and homes, building the first no-imported-oil-economy in the US with solar panels covering casinos and wind turbines on all the mountainsides.)

    Explaining CO2: It’s like wearing a coat in the summer, you get too hot. Hats, scarves, gloves, … nothing is like CO2, the stuff you get when you burn the fuels of the 19th Century.

    Vision: Electricity from the sun, from heat in the earth, from the wind and the tides – energy that’s pulsating around the earth. And the coolest energy, super high-tech efficiency. We lose most of our energy, capture that with technologies we already have and we don’t have to worry about global warming.

    Anything to expand upon for congressional staffers?

  14. Colorado Bob says:

    There is a pattern is these big disasters . That is the low ball numbers in the hours just after they begin to unfold. That seems to be taking place with the estimates of the crop damage in the Philippines. These early numbers get set in stone by the media. Just see the early flow rates out of the Deep Water disaster as an example.

  15. Colorado Bob says:

    The world’s largest F4 tornado has just crossed Luzon, and hey the rice harvest only lost 10 %. That’s the spin at this point.

  16. Colorado Bob says:

    An echo from the Yale poll –

    Is new global warming poll cause for despair?
    Poll points way ahead for climate change communication

  17. Colorado Bob says:

    ISLAMABAD — The devastating floods that swept the whole of this nation damaged or destroyed hundreds of bridges and knocked out several miles of key highways. Much of the nation’s cotton and wheat harvest was devastated.

    Less appreciated, however, is the severe blow the flooding dealt to Pakistan’s electricity supply.

  18. Robert says:

    Chines electric cars are careering ahead but for all the wrong reasons, I suspect.

    “Red China is not going electric because it has suddenly turned green. Yes, the environment is an important and hard-to-ignore issue. (The World Bank estimates that 16 of the 20 most polluted cities in the world are in China.) Electric cars could help alleviate the smog that chokes China’s traffic-clogged streets — one traffic jam on a highway outside Beijing this summer lasted 10 days — by transferring the exhaust from tailpipes to far-off utility smokestacks. And electric cars will generate slightly lower greenhouse-gas emissions than gasoline cars even if the electricity that powers them comes from dirty fossil fuels. (In China around 75% of the power is generated from coal.)”

    [JR: Why is this a wrong reason? Seems fine to me. It’s why CA was originally interested in EVs. Also, you can more easily switch power sources to carbon free in, say, 10 years than cars. ]

  19. Jeff Huggins says:

    The Keys to the Car

    My oh my. This is fascinating and worrisome info, and I have three thoughts for now:

    First, if the media don’t cover this — and cover it well and loudly — that will be “it”, for me, regarding the media. It will demonstrate — for the Nth time now — a complete and utter failure on the part of our media. I’m “calling” to Andy Revkin, here, to GET THIS COVERED WELL. Otherwise, the grade from me is an F. If The New York Times doesn’t cover this, and well, what then shall we make of their editorial-critique from yesterday or the day before? Just another example of how they critique others, periodically, in a serious-sounding editorial, even as they themselves contribute to the problem.

    Second, if we (middle-aged and older adults, though still young at heart, but less so each day that we don’t take action!) don’t face and act to address this problem, and fast, then my suggestion to younger generations is that they should take the keys to the car away from us. I mean that in a figurative but real sense. If we (adults) aren’t “driving the car” responsibly — as we aren’t, presently — then it’s time for the younger generations to speak out strongly and either insist that we do or else grab the keys from us. That’s the bottom line. “Mom and Dad, if you don’t get your act together, I’ll get it together for you and for me.” In earlier days, parents would have control of the literal keys to their literal cars, and teenagers would have to ask. These days, if we don’t get our act together as older adults, young generations (late teens, twenties, thirties) should begin to insist on “the keys to the car” of human political and societal change, and they should not take “no” for an answer. Nor should they hesitate. Nor should they have much patience for excuses.

    Third, I suggest that someone figure out a better metaphor or way to explain this, to many audiences. The thermostat explanation works “to a degree” (sorry for that), but it seems to me that that comparison, although it works in some sense, doesn’t satisfy, convince, or get the “aha!” reaction. Perhaps the thermostat explanation works in some senses, and perhaps it will work with people who can “get” that and don’t have other questions. But it fails (I think) to make what’s happening EASY to understand. It seems to me that there must be better examples, and more natural examples, that more people can connect with. Off the top of my head, I can’t think of any, but something tells me that they exist. Clearly, it will be very helpful to be able to explain this to people clearly and in a way that they “get”. Finding a way to do so will be vitally important.

    In any case, great papers and great post, Joe. Bravo. Yikes. Oh my.


  20. Mike Roddy says:

    Dan B, #13, I like your ideas about communicating with Congressional staffers. I also learned during my time there that they often get the tom tom drums going on key issues.

    Let’s see if a Big Green organization runs with this. They all have offices in DC, and it’s about time they actually became proactive, instead of sitting on their asses and commissioning position papers.

  21. viennariver says:

    Very informative post, I’d be interested in seeing more like this, particularly with excellent references to literature

  22. Ed Hummel says:

    I agree that this is an extremely important study that should receive wide dissemination throughout all media outlets and be given to all present government officials and also to all those currently running in the next election. Even though all the basic research of the last 150 years has gradually pointed in the direction of CO2 being a very powerful thermostat, this study finally puts some strong numbers on the matter in a way that should be easy for anyone with half a brain to understand. Of course, that won’t take into account those who continually pullute their brains with fuzzy coolaid. But at least a majority of those who still have legitimate doubts because of the constant bombardment by deniers and their corporate backers should be able to see through all that and understand why some of us have been very alarmed for the last 20 ro 30 years. I would propose that we all immediately send copies of this study (Joe’s summary here would be a good copy!) to all our local, state and Congressional government officials as well as all those candidates currently running for office, while Joe and other more high profile people can work on the Obama administration, including lower level staffers and policy people who actually do all the real work and then advise their well known bosses. It may not work, just as a lot of other stuff that’s been tried has failed, but it’s better than doing nothing!! Sometimes the Aha! moment that actually causes a paradigm shift comes from the least expected quarters. We all need to keep pushing until such a shift occurs, or else we all know the consequemces.

  23. John McCormick says:

    RE # 20

    Mike, Your suggestion that Capitol Hill staffer be given copies and briefed on their content by big green may not be as effective as calling upon people like Stu Ostro, Jeff Masters, Gavin, etc.

    We are up against a war machine and we cannot send the bugle corps in to do the fighting. We need special forces able to present the finding of these reports as unbiased professionals ready to give clear meaning to their content.

    And, while we are discussing boots on the ground ready to battle the deniers, how about the same team of Hill presenters/interpreters visiting some of the signers of the various Cornball Coalitions’ edicts and pronouncements to their fellow christian believers to challenge them these reports are not biblical heresy but logical science.

    Mike, I looked into the Cornball’s many affiliated organizations and their webpages, membership and sources of funding. Their rosters include people who should be standing trial in the World Court….O. North as one example or R. Cheney.

    We have to find (and there are many) Cornball counterparts who are believers of AGW fighting back against the deniers and the Scaifs and Sun Yung Moon and standing alone. Putting the Cornballs up to public scrutiny is a valid and vital campaign…I could imagine an Oliver Stone new take on a Wall Street movie where the money handlers plan, direct and fund the groups that convince the public AGW is a hoax and thereby, unwittingly, bring about the destruction of capitalism as they succeed with their end point.

    John McCormick

  24. Nick Palmer says:

    But, but, but! The denialists point out that CO2 is a tiny percentage of the atmosphere and therefore must be a very small part of the natural greenhouse effect and also that any effect from CO2 is saturated anyway. In short, that CO2 has very little effect.

    Surely the denialists must now acknowledge that these model runs without CO2 in them, show that we must be living on a snowball Earth right now and have been doing so for millions of years. And yet, we’re not…

    How will they wriggle out of this one?

  25. Mike#22 says:

    Instant classic, old school thermostat. All it’s missing is the “SAFE” label at the 300 to 350 ppm range.

    At the NASA page it looks like the image credit goes to one “Lilly Del Valle”.

  26. Robert says:

    Joe re #18

    In my view its the “wrong reason” because China’s growth in coal consumption is totally dwarfing its more green-sounding initiatives. As the article I linked to explains, the main reason for their interest in EVs is because they recognise that oil is running short (or will do in the sort of quantities they will need!) and EVs give them a potential way to power a massively increasing fleet of cars from the only fossil fuel they have lots of – coal.

    As I have comemnted before, the growth in Chnia’s coal consumption is staggering, with 3 month’s growth alone equal to the entire coal consumption of the UK. Add to that the unbelievable rate of growth in car sales, reported here as being 45% in 2009 and from a climate perspective I struggle to find anything positive to say about it.

    [JR: The coal is quite bad. But the EVs are between slightly good and very good.]

  27. Raul M. says:

    very nice to study IR absorption, but is there a
    study that shows the difference in the absorptive
    values of GHG’s due to Latitude? Meaning as the
    absorption in the atmosphere is a direct absorption,
    and the length of the absorptive field is greatly
    increased because the IR has the potential to travel
    through the Earth’s atmosphere from side to side at
    the poles, Does the amount of absorption by individual
    CO2’s become greater at the higher latitudes even though
    there is the bounce effect of the albedo of the desert
    at the equater? The reflection of the ice surfaces
    at the poles would also give the individual CO2’s
    more chances to absorb solar radiation. Also do individual
    CO2’s have a limit to the amount of solar radiation
    each may absorb. Or to say is one absorption each
    CO2’s limit until each releases said absorption?

  28. Robert says:

    Raul M – one of the best resources on the net for explaining climate science and how the greenhouse effect works is this one by Spencer Weart:

    It is more complicated than you might imagine, as this excerpt shows:

    “The early experiments that sent radiation through gases in a tube, measuring bands of the spectrum at sea-level pressure and temperature, had been misleading. The bands seen at sea level were actually made up of overlapping spectral lines, which in the primitive early instruments had been smeared out into broad bands. Improved physics theory and precise laboratory measurements in the 1940s and after encouraged a new way of looking at the absorption. Scientists were especially struck to find that at low pressure and temperature, each band resolved into a cluster of sharply defined lines, like a picket fence, with gaps between the lines where radiation would get through.(24) The most important CO2 absorption lines did not lie exactly on top of water vapor lines. Instead of two overlapping bands, there were two sets of narrow lines with spaces for radiation to slip through. So even if water vapor in the lower layers of the atmosphere did entirely block any radiation that could have been absorbed by CO2, that would not keep the gas from making a difference in the rarified and frigid upper layers. Those layers held very little water vapor anyway. And scientists were coming to see that you couldn’t just calculate absorption for radiation passing through the atmosphere as a whole, you had to understand what happened in each layer — which was far harder to calculate.”

  29. Jay Dee Are says:

    A nit in the Flux vs Wavenumber figure: 294K=21C, not 31C.

    I don’t understand why the 294K black-body emission curve is used in this figure. The annual average surface temperature is around 288K, or 15C. A direct comparison to Figure 1 of Kiehl and Trenberth’s 1997 planetary heat balance and GHG attribution paper would be facilitated if the figure used wavelentgh as the horizontal axis. I’m not sure what wavenumber means in the figure. Is it 1/wavelength or 2*pi/wavelength?

    The flux values given here don’t appear to agree with the KT97 flux values, by about a factor of 2. I think KT97 is in the right ball park.

  30. Mike Roddy says:

    John McCormick,

    I would also prefer to see climate scientists approach government offices, and insist on this information being both read and understood. Organizing this may be problematic- Gavin works for the government, and may be in an awkward position, but maybe Jeff could find recruits within the American Meteorological Society- which probably has the most forceful climate change statement of all of them. Hansen has led on moral and spiritual fronts, but the time is ripe to be more forceful on communicating the evidence.

    Maybe this is the excuse we need to get the scientific “Special Forces” into the halls of government, and say how they feel about Congressmen calling on people like Lord Monckton to provide testimony on this subject.

    At some point, climate scientists have to just step up and say- we’re sick of all of the bullshit. It’s time that the people running the largest economy on earth got a clue about what is actually going on. Most denier Congressmen won’t change, but all it takes is a few dozen, and the remnants may find themselves isolated and humiliated.

    Scientists have said it on blogs like RC and here, and (in guarded language) in professional society position papers. It hasn’t worked. I think the bugle corps from Big Green can certainly insist on circulating the facts to government offices, but maybe you’re right, we need to think bigger.

    During the Vietnam War, professors stepped out of their offices to travel all over the place for teach ins, and joined sit down nonviolent protests. Too many professors now appear to be cowed, willing to express their anger and frustration only to each other. The times are far too serious for global warming to become a parlor debate. What say you, CP reading climate scientists?

  31. Jeff Huggins says:

    Regarding Mike Roddy’s Comment 30

    I agree. It’s time for ALL scientists to speak up and stretch your comfort zones. The view that scientists can’t or shouldn’t speak up is entirely misguided when it comes to any issue of this importance or even any issue that’s half this important. With understanding comes responsibility, and being human involves basic responsibilities anyhow. Indeed, at this point it is deeply irresponsible not to speak up. Jim Hansen and (too few) others started speaking up at the right time, and that was LONG ago.

    The scientific societies and trade organizations (e.g. ACS) should develop real person-to-person campaigns involving real scientists calling face-to-face on the media, key politicians, key business leaders, and (also) university leadership. Preferably two or three or more scientists together, for impact. Don’t take no for an answer. Perhaps groups of scientists should be assigned to “call on” different companies and politicians.

    Indeed, I would be happy to meet with a few organizations as part of a group of scientists (i.e., accompanying them and “chipping in” to the conversation in meetings with a few organizations with which I have experience). I’d also be happy to help an organization, in my “spare time”, to develop and implement such a targeted (and wise and responsible) campaign. For example, I was once a chemical engineer and member of the ACS long ago, and I applaud the ACS’s Position Statement, and I’d be happy to help them develop and implement a person-to-person type campaign. Or, the AAAS. Or, several of those organizations in a joint effort (the ideal approach). We need to do something smart, responsible, credible, targeted, and most of all effective.



  32. William P says:

    There is a huge disconnect in most of the above discussion. For example:

    “Your combined articles on GHG’s and the effect on climate is good reading.As a person that tries to look for solutions, I am going to highlight the enormous opportunities for up and coming young people or professionals who are looking for a long lasting career.”

    A “long lasting career”. Sir, did you notice? We are talking about the end of the world here. The science in these papers is nifty and a contribution and understandable and all. But do we put a sunny outlook about “long lasting careers” on Doomsday?

    We just can’t bring ourselves to discuss actual doom. We desperately want to assume “business as usual” in this world and our little everyday world. After all, there’s that grant application we need to submit!

    How do you take CO2 out of the atmosphere? No ones knows for sure. How long would that take, by the way, if we had a method? What kind of infrastructure machinery would need to be built?

    Come on, folks. We are indeed in “uncharted territory” and blasting ahead at full speed. And there is not reasonable way to believe we will stop or slow our speed toward whatever awaits us.

    There is no discussion of what happens if soot and other particulate matter that can out of the atmosphere fast, does for some reason come out whereby the temperature immediately shoots up. It happened in the 9-11 crisis where world temperature immediately rose 1 degree C due to condensation trails and other material thrown out by jet airliners stopped being produced. What if some new crisis stopped more than jets – factories, for example as could happen in an economic collapse? Or some other shock to the world.

    We need to do some immediately defensive planning. Climate scientist James Lovelock says survival may be possible at the poles. James Hansen believes – no, earth will become a new Venus at 450 degrees C.

    Let’s get real and close this disconnect where we sit around and oooo and awww over good scientific papers and instead talk about getting prepared for what looks like inevitable disaster.

    Or are all heads firmly in the sand regarding that discussion?

  33. Raul M. says:

    Thanks Robert for the link.
    Saw emergence of carbon being changed by
    cosmic rays in upper atmosphere.
    Seems that if complex life forms emerge in future
    mallinia there will be that fossil record available
    for disccovery as indicator of dramatic change
    in history of the Earth.

  34. Raul M. says:

    The Grand disconnect might be the shift from further
    understanding of Earth Science to the dramatization
    of how a CO2 might behave. Acceptance of radiant energy,
    the release of great heat, satisfaction of having behaved
    naturally, then the receptivity for accepting more radiant
    energy? Must say that the satisfaction stage is a great
    jump of dramatization.
    Oh, American cartoons are amazing!

  35. Robert says:

    Raul M –

    “…if complex life forms emerge in future
    mallinia there will be that fossil record available
    for disccovery as indicator of dramatic change
    in history of the Earth.”

    Or rather more obviously a seam of fossilised iPods, Moulinex Mixers and other assorted detritus that define our civilistion.

    Joe – on China, in the absence of anything remotely resembling an emissions or climate policy I follow the numbers – the economic growth, the growth in fossil fuel consumption, the growth in cars, air-con, fridges, freezers and so on. It is natural to expect China to follow the same route as the west and they are doing so with amazing speed and success. Whether it makes them happy is another question.

    On this basis I expect China to consume coal, oil and gas until there is no more to extract or import. If this is indeed realistic it is counter-productive to view the situation through rose-tinted spectacles. People in the west are more likely to get angry about emissions and demand action if they realise (a) it’s getting worse faster than anyone thought and (b) it’s not just our fault.

  36. John McCormick says:

    re #30

    Mike, you are likely aware of the the climate science seminars the American Meteorological Society has sponsored on Capital Hill for several years. I have attended numeous sessions featuring the best scientists out there; Mark Serezze, Jim Hansen, Trenbreth, etc.
    They were always well attended by staffers and interns. Much information was provided and hopefully conveyed back to the Leg. Directors and Admins in the Congressional office.

    Lately, the sessions have been put on hold for some unknown reason and now we need AMS to step up more than ever.

    Below is a list of the DC office staff. Maybe you recognize or know some one there. A call to the office might persuade them to get back into the game.

    Depending upon the verdict of our democratic system in November, the quality and integrity of Congressional discussions on climate change will either slide along or be buried. Regardless. AMS could, again, be invited to host more frequent seminars and hammer the message into the heads of the legislative body.

    AMS D.C. Office

    American Meteorological Society
    1120 G Street, NW Suite 800
    Washington, DC 20005-3826

    Main Telephone Number: 202-737-9006; Fax: 202-737-9050

    Policy Program

    Director and Senior Policy Fellow
    William H. Hooke; telephone 202-737-9032, ext. 420; e-mail:

    Assistant Director and Senior Policy Fellow
    Paul A. T. Higgins; telephone 202-737-9032, ext 433; email:

    Senior Policy Fellow
    Robert W. Corell; telephone 202-737-9032 , ext. 409 (voicemail only);

    Senior Policy Fellow
    Genene M. Fisher; telephone 202-737-9032, ext. 422; e-mail:

    Program Assistant
    Wendy M. Thomas; telephone 202-737-9032, ext. 427;

    Program Assistant
    Gina M. Eosco; telephone 202-737-9032, ext. 440; e-mail:

    Administrative Assistant
    telephone 202-737-9032, ext. 436

    John McCormick

  37. espiritwater says:

    I saw a wonderful documentary last night, called “The People Speak” narrated by Howard Zinn. It “gives voice to those who spoke up for social change throughout US history, forging a nation bottom up”. Basically, it tells of the immense struggle the people of this country went through in order to force the top cats to do anything worthwhile… whether for our civil rights issues, to end the Vietnam war, or whatever. Basically, it says that democracy is not a spectator’s sport and we have to be willing to give everything, perhaps even our lives in order to force those at the top to do what’s necessary. Basically, we have a long way to go before they will do sh__ about climate change. It’s an excellent documentary and all I could think about after viewing it was how I wanted to watch it again!

  38. Jeff Huggins says:

    espiritwater (Comment 37), thanks very much for the tip about “The People Speak”. I wonder if it’s available on DVD. We need to take that sort of message to heart.

    Thanks again.


  39. Solar Jim says:

    One aspect of the message seems strait forward to me.

    Oil is not an energy resource and there is no energy “in” petroleum. Energy IS the oil. Of the two categories that can describe all physical phenomena on earth, matter and energy, oil is the liquid phase of carbon-containing matter (not “energy”) that life and geologic time has sequestered for our present existence by the grace of climate.

    By economically defining this matter/material as an energy resource and providing trillions of dollars of historic subsidies via dominant federal economic policy of “cheap fuels,” we have cooked the books and are now cooking the planet. This will become evident as the effects we experience today from 1970’s emissions aggravate toward astonishing effects coming in several decades from today’s much larger emissions, unless there is wholesale abandonment of federal (and now global) policies of “cheap fuels” and begin counter actions.

    Buried carbon can no longer be defined as “fuel.” It is a material. A special material that when oxidized can heat the planet many thousands of times greater than its heat of combustion. We are now spending a dollar for “heat” while ignoring a thousand dollars of associated pain.

    We have a national security risk of clear and present danger, economics be damned. Shall we have a controlled bankruptcy of our “energy” industry or a cataclysmic collapse of food and water and all important ecologic systems on the planet? Are we truly so corrupt as not to act?