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Climate Change: The 40 Year Delay Between Cause and Effect

Posted on 22 September 2010 by alan_marshall

Guest post by Alan Marshall from climatechangeanswers.org

Following the failure to reach a strong agreement at the Copenhagen conference, climate skeptics have had a good run in the Australian media, continuing their campaigns of disinformation. In such an atmosphere it is vital that we articulate the basic science of climate change, the principles of physics and chemistry which the skeptics ignore.

The purpose of this article is to clearly explain, in everyday language, the two key principles which together determine the rate at which temperatures rise. The first principle is the greenhouse effect of carbon dioxide and other gases. The second principle is the thermal inertia of the oceans, sometimes referred to as climate lag. Few people have any feel for the numbers involved with the latter, so I will deal with it in more depth.

The Greenhouse Effect

The greenhouse effect takes its name from the glass greenhouse, which farmers have used for centuries, trapping heat to grow tomatoes and other plants that could not otherwise be grown in the colder regions of the world. Like glass greenhouses, greenhouse gases allow sunlight to pass through unhindered, but trap heat radiation on its way out. The molecular structure of CO2 is such that it is “tuned” to the wavelengths of infrared (heat) radiation emitted by the Earth’s surface back into space, in particular to the 15 micrometer band. The molecules resonate, their vibrations absorbing the energy of the infra-red radiation. It is vibrating molecules that give us the sensation of heat, and it is by this mechanism that heat energy is trapped by the atmosphere and re-radiated to the surface. The extent to which temperatures will rise due to a given change in the concentration of greenhouse gases is known as the “climate sensitivity,” and you may find it useful to search for this term when doing your own research.

Most principles of physics are beyond question because both cause and effect are well understood. A relationship between cause and effect is proved by repeatable experiments. This is the essence of the scientific method, and the source of knowledge on which we have built our technological civilization. We do not question Newton’s laws of motion because we can demonstrate them in the laboratory. We no longer question that light and infrared radiation are electromagnetic waves because we can measure their wavelengths and other properties in the laboratory. Likewise, there should be no dissent that CO2 absorbs infrared radiation, because that too has been demonstrated in the laboratory. In fact, it was first measured 150 years ago by John Tyndall [i] using a spectrophotometer. In line with the scientific method, his results have been confirmed and more precisely quantified by Herzberg in 1953, Burch in 1962 and 1970, and others since then.

Given that the radiative properties of CO2 have been proven in the laboratory, you would expect them to be same in the atmosphere, given that they are dependent on CO2’s unchanging molecular structure. You would think that the onus would be on the climate skeptics to demonstrate that CO2 behaves differently in the atmosphere than it does in the laboratory. Of course they have not done so. In fact, since 1970 satellites have measured infrared spectra emitted by the Earth and confirmed not only that CO2 traps heat, but that it has trapped more heat as concentrations of CO2 have risen.

The above graph clearly shows that at the major wavelength for absorption by CO2, and also at wavelength for absorption by methane, that less infrared was escaping in to space in 1996 compared to 1970.

After 150 years of scientific investigation, the impact of CO2 on the climate is well understood. Anyone who tells you different is selling snakeoil.

The Thermal Inertia of the Oceans

If we accept that greenhouse gases are warming the planet, the next concept that needs to be grasped is that it takes time, and we have not yet seen the full rise in temperature that will occur as a result of the CO2 we have already emitted. The Earth’s average surface temperature has already risen by 0.8 degrees C since 1900. The concentration of CO2 in the atmosphere is increasing at the rate of 2 ppm per year. Scientists tell us that even if CO2 was stabilized at its current level of 390 ppm, there is at least another 0.6 degrees “in the pipeline”. If findings from a recent study of Antarctic ice cores is confirmed, the last figure will prove to be conservative [ii]. The delayed response is known as climate lag.

The reason the planet takes several decades to respond to increased CO2 is the thermal inertia of the oceans. Consider a saucepan of water placed on a gas stove. Although the flame has a temperature measured in hundreds of degrees C, the water takes a few minutes to reach boiling point. This simple analogy explains climate lag. The mass of the oceans is around 500 times that of the atmosphere. The time that it takes to warm up is measured in decades. Because of the difficulty in quantifying the rate at which the warm upper layers of the ocean mix with the cooler deeper waters, there is significant variation in estimates of climate lag. A paper by James Hansen and others [iii] estimates the time required for 60% of global warming to take place in response to increased emissions to be in the range of 25 to 50 years. The mid-point of this is 37.5 which I have rounded to 40 years.

In recent times, climate skeptics have been peddling a lot of nonsense about average temperatures actually cooling over the last decade. There was a brief dip around the year 2000 following the extreme El Nino event of 1998, but with greenhouse emissions causing a planetary energy imbalance of 0.85 watts per square metre [iv], there is inevitably a continual rising trend in global temperatures. It should then be no surprise to anyone that the 12 month period June 2009 to May 2010 was the hottest on record [v].

The graph below from Australia’s CSIRO [vi] shows a clear rising trend in temperatures as well as a rising trend in sea-level.

Implications of the 40 Year Delay

The estimate of 40 years for climate lag, the time between the cause (increased greenhouse gas emissions) and the effect (increased temperatures), has profound negative consequences for humanity. However, if governments can find the will to act, there are positive consequences as well.

With 40 years between cause and effect, it means that average temperatures of the last decade are a result of what we were thoughtlessly putting into the air in the 1960’s. It also means that the true impact of our emissions over the last decade will not be felt until the 2040’s. This thought should send a chill down your spine!

Conservative elements in both politics and the media have been playing up uncertainties in some of the more difficult to model effects of climate change, while ignoring the solid scientific understanding of the cause. If past governments had troubled themselves to understand the cause, and acted in a timely way, climate change would have been contained with minimal disruption. By refusing to acknowledge the cause, and demanding to see the effects before action is taken, past governments have brought on the current crisis. By the time they see those effects, it will too late to deal with the cause.

The positive consequence of climate lag is the opportunity for remedial action before the ocean warms to its full extent. We need to not only work towards reducing our carbon emissions to near zero by 2050, but well before then to begin removing excess CO2 from the atmosphere on an industrial scale. Biochar is one promising technology that can have an impact here. Synthetic trees, with carbon capture and storage, is another. If an international agreement can be forged to provide a framework for not only limiting new emissions, but sequestering old emissions, then the full horror of the climate crisis may yet be averted.

Spreading the Word

The clock is ticking. All of us who understand clearly the science of climate change, and its implications for humanity, should do what we can to inform the public debate. I wrote the original version of this article in February 2010 to help inform the Parliament of Australia. The letter was sent to 40 MPs and senators, and has received positive feedback from both members of the three largest parties. To find out more about this information campaign, and for extensive coverage of the science of climate change and its technological, economic and political solutions, please visit my web site at www.climatechangeanswers.org.

References

i Gulf Times, “A Last Chance to Avert Disaster”, available at
 www.gulf-times.com/site/topics/article.asp?      cu_no=2&item_no=330396&version=1&template_id=46&parent_id=26

ii Institute of Science in Society, “350 ppm CO2 The Target”,
  www.i-sis.org.uk/350ppm_CO2_the_Target.php, p.4

iii Science AAAS, ”Earth’s Energy Imbalance: Confirmation and Implications”, available (after free registration) at www.scienceonline.org/cgi/reprint/1110252v1.pdf, p.1

iv NASA, “The Ocean Heat Trap”, available at www.ocean.com, p.3

v NASA GISS temperature record (see http://climateprogress.org/2010/06/03/nasa-giss-james-hansen-study-global-warming-record-hottest-year/)

vi CSIRO, “Sea Level Rise”, available at www.cmar.csiro.au/sealevel/sl_drives_longer.html

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Comments 1 to 50 out of 65:

  1. Could this same 40 year lag in increased tempeatures be used as an 'explanation' by a sceptic for the Solar influence which peaked way back in the last century?
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    Response: No, the way climate time lag works is when the planet is in energy imbalance (eg - more energy coming in than going out), the planet steadily accumulates heat and warms. As it warms, it radiates more heat out to space until eventually, the energy out equals the energy in and the planet is back in equilibrium. So the way climate time lag works is the planet gradually warms over decades and the energy imbalance gradually shrinks.

    That's not what we've seen over the last half century. After solar activity peaked in the mid-20th century, the planet's energy imbalance - rather than shrink - has actually increased as CO2 levels have increased.
  2. Is this time lag an absolute? Co2 now at around 390ppmv will 'only Be felt' in temperatures around the year 2050 (with all the significant feedback's)Or does that 390ppmv today have any effect on us?

    Hansen has said that ice will melt and soften up in the arctic at 375-400ppmv- which is what is happening-

    Or does time lag mean the CO2 emitted today will be around 30 years from now?

    Anyone care to explain?
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  3. re#1.Perseus.

    Yes, there is no reason why the ~40 year ocean heat lag should only apply to greenhouse gases. It also applies to heat from the sun. Of course it isn't mentioned, for sake of 'brevity', or some such.

    The 'energy imbalance' referred to by the moderator and claimed to be increasing since the mid 20th century, as I understand it,has been modelled, not measured. And yes, you guessed it, modelled using greenhouse gas models. You can get a feel for their reasoning from the very first sentences in the following abstracts.

    1.
    Earth's Energy Imbalance: Confirmation and Implications
    James Hansen,1,2* Larissa Nazarenko,1,2 Reto Ruedy,3 Makiko Sato,1,2 Josh Willis,4 Anthony Del Genio,1,5 Dorothy Koch,1,2 Andrew Lacis,1,5 Ken Lo,3 Surabi Menon,6 Tica Novakov,6 Judith Perlwitz,1,2 Gary Russell,1 Gavin A. Schmidt,1,2 Nicholas Tausnev3

    "Our climate model, driven mainly by increasing human-made greenhouse gases and aerosols, among other forcings, calculates that Earth is now absorbing 0.85 ± 0.15 watts per square meter more energy from the Sun than it is emitting to space. This imbalance is confirmed by precise measurements of increasing ocean heat content over the past 10 years."

    http://www.sciencemag.org/cgi/content/abstract/308/5727/1431

    2.
    "Using a climate model that incorporates anthropogenic greenhouse gas emissions, scientists have recently concluded that the Earth is absorbing more energy than it emits. The energy imbalance, when compared to temperature measurements, indicates a lag in atmospheric warming."

    http://www.wri.org/publication/content/7678

    3. Roy Spencer has some alternative ideas.

    http://www.drroyspencer.com/2009/07/how-do-climate-models-work/
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  4. sleepership, the cause of the lag is explained in the article. Basically, just as when you put a pot of water on the stove it does not immediately begin releasing heat to the air above the water so also does the extra heat going into the oceans take time to make its way into the atmosphere.

    That said, yes there is also an immediate effect... some of the additional heat goes directly into the atmosphere. However, the surface of the Earth is 70% water. When you add in that this water is always moving and the vast VOLUME of the oceans it is obvious that the vast majority of the warming goes first into the oceans.

    thingadonta, 'for sake of brevity'? Gee, I'd think it wasn't mentioned because the high solar activity in question was ~80 years ago.
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  5. Thanks number 4 CB

    The time lag as you explained- the immediate effects also can be felt- theoretically- the warming we feel today be goes back to the late 70s or early 80s- 30-35 years ago when the CO2 level was 330-340ppm.

    Hansen and McKibben have put a maximum level of 'safe' CO2 at 350- but even that may be to high- but for all practical purposes 350ppmv is the goal we can only hope to reach.
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  6. "With 40 years between cause and effect"

    This is perplexing. I see the role of thermal inertia as a mechanism for delayed heating response, but I have to wonder about what happens in the other direction. As is well known, the '91 Pinatubo eruption produced both a short-term cooling and flattening in the rate of increase of atmospheric CO2 (see Robock 2003 and the MLO mean rate of change table.

    Why no lag in this case? Would such a large volcanic event be too short-lived to even make a dent in the lag you discuss here?
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  7. There is a new paper out from NOAA on deep ocean temperature measurements and I’m wondering how significant its findings are.
    Warming of Global Abyssal and Deep Southern Ocean Waters Between the 1990s and 2000s: Contributions to Global Heat and Sea Level Rise
    Budgets


    I can’t find any other work that covers the deep ocean over the globe. My questions are:
    1. Is there any other study that measures that deep over the globe?
    2. Understanding the caveats and assumptions, how much does this help in filling out Earth’s energy budget (Trenberth’s travesty)?
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  8. CO2 @ 390ppm-

    do we see immediate effects? Was the heat the planet experienced this summer from 1980 C02 or from recently?

    If from 1980- when CO2 was just passing 350ppm- then we are in deep deep trouble when today's levels overcome the 'inertia' around the year 2040.

    The ice melt in the arctic seems over the last few years seems at the level of CO2 of between 370-390ppm however.

    It seems that by 2020- an ice free arctic ocean is certainly possible- and that would see the CO2 lag from 1990 around 360ppm- but I assumed that an free arctic in the summer would be the product of a co2 level of 390 +----

    All interesting- the 'Inertia' of lag time in warming seems possible in feedback's and general warming- but as far as Ice melt- the arctic is responding to the levels we currently have.
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  9. grypo, well the study found statistically significant (greater than 97.5% confidence) warming of deep ocean basins (below 4000 m) in the Southern ocean all the way down to the sea floor. That should put to rest arguments that heat can't possibly be making its way into the deep oceans quickly enough to be responsible for discrepancies in the energy and SLR balance calculations.

    However, the amount of data gathered for this study is not sufficient to develop a robust GLOBAL picture of deep ocean warming. They make a good case that deep ocean heat needs to be accounted for in the energy and SLR budgets, but can't show that these make up the current budget gaps. With the available data they estimate 0.027 W/m^2 and 0.1 mm/yr global impacts from the sampled deep basins.
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  10. muoncounter and sleepership,
    the meaning of lag is not that the response starts whith a delay, but that the full effect will be seen later. If we apply a constant forcing equivalent to that of Pinatubo eruption, for example, it will cool much more than what we've seen; it cooled a few tenth of a degree just because it was very short (in time) and because of the inertia (lag) of the climate system.
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  11. Following on Riccardo's comments and going back to the 'pot of water' analogy... Pinatubo was the equivalent of turning the stove off for several seconds. All that dust in the air had an immediate impact on temperatures, but within a couple of years it had all fallen back to the surface and was no longer a factor. Yes, less heat went into the oceans during those few years and thus there is also a 'long term' impact, but since the 'forcing' from the dust only lasted a short time the cumulative cooling effect was small. When you add CO2 to the atmosphere the level stays elevated and thus continues to build up greater heat which circulates around in the oceans for decades before making its way to the atmosphere.
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  12. Why Hasn’t Earth Warmed as Much as Expected?, AMS Journals, Schwartz et al., 2010.:
    “The observed increase in global mean surface temperature (GMST) over the industrial era is less than 40% of that expected from observed increases in long-lived greenhouse gases together with the best-estimate equilibrium climate sensitivity given by the 2007 Assessment Report of the Intergovernmental Panel on Climate Change (IPCC).”
    “Current uncertainty in climate sensitivity is shown to preclude determining the amount of future fossil fuel CO2 emissions that would be compatible with any chosen maximum allowable increase in GMST; even the sign of SUCH ALLOWABLE FUTURE EMISSIONS IS UNCONSTRAINED.”

    Ensemble reconstruction constraints on the global carbon cycle sensitivity to climate, Frank et al. 2010, Nature :
    “But themagnitudeof theclimate sensitivityof theglobal carboncycle (termed c), and thus of its positive feedback strength, is under debate, giving rise to large uncertainties in global warming projections.”.
    “The average correlation between individual temperature reconstructions and the mean CO2 record is 0.47 over the pre-industrial 1050–1800 period (all years are AD), increasing to 0.57 with a 50-year CO2 response lag—such timing is consistent with modelled CO2 response to a temperature step change.” “Yet, great scatter in c, from a few to more than 40 p.p.m.v. per uC, closely reflects the choice of the individual temperature and/or CO2 estimates used for analysis. Particularly relevant to constraining sensitivities of the Earth’s coupled climate system is the amplitude of hemispheric to global-scale ...”
    “Approximately 40% of the uncertainty related to projected warming of the twenty-first century stems from the unknown behaviour of the carbon cycle, which is an important component of the global climate system.” “Coupled carbon–climate models show a wide range in feedback strength, with 20–200 p.p.m.v. of temperature-driven CO2 by 2100 ...”
    “Our results ... ... suggest 80% less potential amplification of ongoing global warming.”.

    Reconstruction of the history of anthropogenic CO 2 concentrations in the ocean. Khatiwala et al. 2009.: “Although much progress has been made in recent years in understanding and quantifying this sink, considerable uncertainties remain as to the distribution of anthropogenic CO 2 in the ocean, its rate of uptake over the industrial era, and the relative roles of the ocean and terrestrial biosphere in anthropogenic CO 2 sequestration.”

    Summarize: ... such allowable future emissions is unconstrained ..., ... large uncertainties in global warming projections ..., ... great scatter ..., ... 40% of the uncertainty ..., ... wide range ..., ... 80% less potential amplification ..., ... considerable uncertainties ...

    ... and I have to invest billions of dollars in synthetic trees ... ?
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  13. Thank you CB!

    Arkadiusz Semczyszak
    "Why Hasn’t Earth Warmed as Much as Expected?, AMS Journals, Schwartz et al., 2010.:"
    This paper discusses some uncertainty as to whether Climate Sensitivity is at the low range or whether aerosols contribute more to cooling than previously thought. But to understand fully what this paper suggests, you need to read the conclusions:
    "Even if the earth’s climate sensitivity is at the low end of the IPCC estimated ‘‘likely’’ range, continued emission ofCO2 at the present rate would exhaust in just a few decades the shared global resource of the incremental amount of CO2 that can be added to the atmosphere without exceeding proposed maximum increases in GMST. If the sensitivity is greater, the allowable incremental emission decreases sharply , essentially to zero at the present best estimate of climate ensitivity, and is actually negative for greater values of this sensitivity.

    "Reconstruction of the history of anthropogenic CO 2 concentrations in the ocean."
    Uncertainties as to the distribution of CO2 sink in the ocean does not change what we know about the carbon cycle and what content is in the atmosphere. The passage before what you quoted in the abstract says:
    "The release of fossil fuel CO2 to the atmosphere by human activity has been implicated as the predominant cause of recent global climate change1. The ocean plays a crucial role in mitigating the effects of this perturbation to the climate system, sequestering 20 to 35 per cent of anthropogenic CO2 emissions2, 3, 4. Although much progress has been made in recent years in understanding and quantifying this sink"


    "... and I have to invest billions of dollars in synthetic trees ... ?"
    Nothing you've posted here would lead anyone to not invest in mitigation and adaption.
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  14. What stood out most in the article was the line "The mass of the oceans is around 500 times that of the atmosphere." This is an extremely compelling point specifying that the total effect of atmospheric conditions on climate change has at best a 1/500 effect compared to the oceans. This does not even include the effect of the land mass as well (perhaps another 1/7 more land/ocena versus atmospheric effect). This is the key point that has mad me a true skeptic on the oeverall effect of CO2 causing global warming. All energy in the atmospaher has a 1/500 effect compared to the oceans, and C)2 has a 1/100 effect compared to all greenhouse gases. The number DO NOT add up.
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  15. #12 Arkadiusz Semczyszak

    As usual, you're cherrypicking, and ignoring the authors' interpretation of their own work.

    "The more carbon dioxide you put in, the more acidic the ocean becomes, reducing its ability to hold CO2" said the study's lead author, Samar Khatiwala, an oceanographer at Columbia University's Lamont-Doherty Earth Observatory. "Because of this chemical effect, over time, the ocean is expected to become a less efficient sink of manmade carbon. The surprise is that we may already be seeing evidence for this, perhaps compounded by the ocean's slow circulation in the face of accelerating emissions...."

    Khatiwala says there are still large uncertainties, but in any case, natural mechanisms cannot be depended upon to mitigate increasing human-produced emissions. "What our ocean study and other recent land studies suggest is that we cannot count on these sinks operating in the future as they have in the past, and keep on subsidizing our ever-growing appetite for fossil fuels," he said.
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  16. Greenhouse gases do trap radiation, but greenhouses stay warm largely because they prevent convection. Thus, the statement, "Like glass greenhouses, greenhouse gases allow sunlight to pass through unhindered, but trap heat radiation on its way out." is incorrect and should be modified. Even in a basic version, statements should be accurate.
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  17. Question: What percentage of the current .8C warming is due to CO2 that was emitted in 1970? Can that be calculated?
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  18. nerndt writes: What stood out most in the article was the line "The mass of the oceans is around 500 times that of the atmosphere." [...] This is the key point that has mad me a true skeptic on the oeverall effect of CO2 causing global warming. All energy in the atmospaher has a 1/500 effect compared to the oceans, and C)2 has a 1/100 effect compared to all greenhouse gases. The number DO NOT add up.

    First off, the statement "C02 has a 1/100 effect compared to all greenhouse gases" is just plain wrong. Because the effects of different GHGs overlap, it's not straightforward to say that gas X causes percentage P of the total effect, while gas Y causes percentage Q. But CO2 clearly has a large warming effect on the climate. See

    How do we know more CO2 is causing warming?
    Water vapor is the most powerful greenhouse gas

    Or, for vastly more detail:

    CO2: An Insignificant Trace Gas?

    As for your general idea that since the mass of the ocean is much greater than the mass of the atmosphere, we can safely ignore climate change ... well, that just makes no sense.

    The mass of the ocean was just as large at the end of the previous interglacial, but that didn't prevent the very radical climate change in which ice sheets spread southward for 80,000 years, eventually covering the place where I now sit with over 2 km of ice. Why would the mere existence of massive oceans prevent us from altering the climate in a similarly dramatic fashion in the opposite direction?

    That's just wishful thinking, frankly.
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  19. #10:"meaning of lag is not that the response starts with a delay, but that the full effect will be seen later."
    In addition to 'turning off the burner' for a bit, the flattened rate of increase in CO2 after Pinatubo also 'took the lid off the soup pot' (its lunch time here). This essentially delays the continued heating and that should have an effect on the furious discussion over Hansen's 1988 projections.

    #11: "continues to build up greater heat which circulates around in the oceans for decades before making its way to the atmosphere. "

    The deep oceans are very cold. I would imagine the lag for measurable ocean heating is orders of magnitude more than 40 years. Since the air heats up (and loses heat) far more rapidly, why does ocean heat storage even enter into the discussion of surface (air) temperatures?
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  20. Is it just me, or are contrarians becoming increasingly sloppy here?

    I guess it's a tribute to the science presented here that there would be so many scientifically poor comments trying to attack the points made in the articles: the more influential a science web site becomes, the more it is perceived as a threat by those who are politically opposed to it. Thus, the greater the number of contrarian/trolling comments.
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  21. beam me up scotty @ #17 - see Quantifying the human contribution to global warming.

    Short answer, it's approximately 100% over the past 35 years and approximately 80% over the past century.
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  22. BmuS #17, dana1981's answer is probably the most useful you'll get. If you are really looking for the warming from CO2 emitted in JUST the year 1970 then we are talking about less than 2 ppm and the resulting warming would be exceedingly tiny. If you meant all CO2 emitted up THROUGH 1970 that's a much bigger factor, but difficult to quantify. Let's say CO2 had stabilized at the 1970 level. I think that was around 320 ppm. In that case, assuming a climate sensitivity of 3 for a doubling of CO2, I get;

    ln(320/280) * (3 / ln(560/280)) = 0.58 C

    Since we are 40 years past 1970 pretty much all of that warming should have now been cycled through into the atmosphere. Obviously, different climate sensitivity factors would yield different results, but the current 0.8 C warming is consistent with the 3 C 'fast feedback' sensitivity estimate.
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  23. On the point made in the lead article of this topic of CO2 properties as having been established in the laboratory, the behavior in the atmosphere should follow.
    The absorption of IR, being thermal energy, heat, in the atmosphere falls within certain limits due, not to the properties of CO2, but must be due that of the environment itself as CO2 can absorb heat to temperatures far in excess of normal conditions without any change of state occurring as this chart shows.
    The ability of it to radiate heat off, transfer heat to other adjacent matter will depend again on the state of the environment rather than any specific property of CO2 given it remains a gas at normal pressures at temperatures well in excess of anything within the normal environment.
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  24. As for your general idea that since the mass of the ocean is much greater than the mass of the atmosphere, we can safely ignore climate change ... well, that just makes no sense.

    The mass of the ocean was just as large at the end of the previous interglacial, but that didn't prevent the very radical climate change in which ice sheets spread southward for 80,000 years, eventually covering the place where I now sit with over 2 km of ice. Why would the mere existence of massive oceans prevent us from altering the climate in a similarly dramatic fashion in the opposite direction?

    That's just wishful thinking, frankly.

    Hi Ned. The point I was trying to make is that the largest contributor to any global warming is not the atmospher, but the water and land masses. The atmosphere only has 1/500 (or less) overall mass than the oceans and has minimal effect. The one time this may not be the case would be in a large catastrophic event (huge volcano or metror strike) which then changes the absorption of energy by the oceans and land masses and quickly causes climate change.
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  25. repsonse to #18 Ned at 02:10 AM on 23 September, 2010

    Ned - Of course global warming and cooling occurs, but CO2 has a minimal effect being a small percentage of greenhouse gas effect and that the atmosphere has a minimal effect on the overall energy of the earth (being more than 1/500 of the totla mass).

    Can anyone here see the big picture? The key point is that mankinds increase of CO2 to the atmosphere pales in comparison to the effects on the oceans and land by other conditions. Atmoshperic conditions are trivial.
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    Moderator Response: See the post (and take the discussion there): CO2 effect is weak
  26. nerndt #25: "Atmoshperic conditions are trivial."

    This is simply false. Basic physics tells us that without the atmosphere the planet would be about 33 C colder... and thus a solid ball of ice.

    The amount of heat retained in the atmosphere itself is SMALL (not "trivial") compared to the amount in the oceans, but the atmosphere is CAUSING a great deal of that oceanic heat accumulation.
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  27. #22:"If you meant all CO2 emitted up THROUGH 1970"
    A cumulative plot using the CDIAC data shows that most of the emissions prior to 1950 or so don't make much of a contribution compared to everything since. See the cumulative graph in the figures here, for example. The caption says "Half of 270 Gtons [the cum to 2000] emitted since 1974". So if we are just now seeing the heating effects of the first half (its ~40 years post 1974) and have yet to see the heating effects of the second half --- ouch!!!

    For example, arctic ice melt started accelerating in the '80s; was that due to cum CO2 up to the 40's? That's why I'm still having trouble wrapping my head around a 40 year lag.
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  28. john,
    "The absorption of IR, being thermal energy, heat, in the atmosphere falls within certain limits due, not to the properties of CO2 [...]"

    It's not so. First of all, IR is an electromagnetic wave as any other. It is emitted by warm bodies and this is why it is associated to heat. The absorption properties of a molecule depend on the characteristic frequencies of vibration of the molecule which in turn depend on the physical properties of the chemical bond. No relation with temperature here.
    The environemnt has an impact on the width of the absorption frequency (and very little on the central frequency) but not on it's ability to absorb or radiate EM waves (apart from extreme "pathological" cases which are not relevant to our atmosphere).
    In short, your claims are physical absurdities.
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  29. CBDunkerson at 06:28 AM, is it not instead that the ocean, and land, heat accumulation that is causing the warmth in the atmosphere.
    Incoming solar radiation must first be intercepted and absorbed by matter on the surface BEFORE being converted to IR that then transfers into the atmosphere.
    How near surface temperatures just below the surface vary over the course of a year indicates that at times incoming solar energy is excess of what is being lost into the atmosphere and so is accumulated as thermal energy below the surface, whilst at other times incoming solar radiation is less than that being lost to the atmosphere from below the surface where the thermal energy stored begins to decline.
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  30. Riccardo at 06:44 AM, I think you are making the same point as I was.
    The properties of CO2 allow it to absorb and radiate thermal energy over a far greater range than what is found in the natural environment, and it is the environment itself that determines the width of the absorption frequency.
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  31. john, I remain extremely confused by both your posts. "far greater range than found in natural environment". What unnatural environment are you talking about then?

    That temperature of surface varies with season is hardly surprising, nor is the globally, annually averaged heat capacity of surface materials varying in any significant way on the time scales we are interested in. I fail to see what you are driving at here.
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  32. johnd,
    I'm making the opposite point, molecular absorption of CO2 (or any other molecule, for that matter) is an intrinsic property of the molecule. Pressure and temperature of the gas only slightly widen and shift the absorption band. Try a google search for pressure and Doppler broadening.
    In accurate radiative transfer codes the broadening effects are taken into account because the "wings" of the wider emission at higher temperature and pressure near the ground is less absorbed in the upper atmosphere. But these are subtleties.
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  33. scaddenp at 08:04 AM, re "unnatural environment", obviously the laboratory Phil, the properties of CO2 as proven in the laboratory as referenced in the lead article, and illustrated in the diagram posted.

    Re your second comment, think cause and effect.
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  34. Riccardo at 08:20 AM, that is exactly the point I am making.
    As the diagram indicates, at 1 bar pressure the absorption band for thermal energy exceeds the range of 200K to 400K, that limitation being solely the range of the diagram.

    For comparison think H2O and the changes of states that occur that affect the absorption and release of thermal energy, and how they relate to the natural environment.
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  35. John, no significant change means no cause. Unlike GHG concentrations. As to whether laboratory measurements are born out in the natural world, then I can only point you at the classic Ramanathan and Coakley 1978 paper which tested just that, confirmed by numerous other studies since.
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  36. Johnd:

    The chart at #23 is just a pressure-temperature phase diagram and has nothing to do with IR absorption bands. It indicates at what pressure/temp combination CO2 changes state eg at 10Bar/225K CO2 will be liquid and boil at 230K. The 200/400 limits of tempeature are just what the creator of the diagram chose.

    It looks like the colored-in version of this.
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  37. johnd,
    in #28 I copied part of your previous post and said it was not true. Maybe now you agree with me.
    In #34 you're switching argument:
    "As the diagram indicates, at 1 bar pressure the absorption band for thermal energy exceeds the range of 200K to 400K, that limitation being solely the range of the diagram."
    As MichaelM already said, there's no relation between a PT diagram and vibrational absorption/emission. That diagram just tells you that at 1 bar pressure CO2 is a gas between 200 and 400 K. Good to know, but then what? There's no thermal energy nor absorption lines shown there.
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  38. Riccardo at 09:18 AM, can you perhaps clarify these points for me,
    1 - at what temperatures does CO2 exist as a gas?

    2 - what is the range of temperatures that CO2 absorbs thermal energy and emits thermal energy?
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  39. John - answer to 1 and 2 would be "all temperatures and pressures found in the atmosphere. (pressures of 1bar or less). Again, the relevance of your questions to anything in climate is hard to guess.
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  40. scaddenp at 10:10 AM, it all comes back to trying to establish how as mentioned in the lead article CO2 "is “tuned” to the wavelengths of infrared (heat)" when it is clear that it absorbs and emits thermal energy at wavelengths beyond that "tuned" range found in the atmosphere.
    Can you elaborate on your answer as to clarify whether CO2 also absorbs and emits thermal energy at temperatures and pressures BEYOND those found in the atmosphere, and thus is not "tuned" to any specific range.
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  41. #25 nerndt

    Atmoshperic conditions are trivial.

    Good to know. Glad that's settled.

    It's really too bad so many climatologists are in the dark on this point. I guess they're just dumb, huh?
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  42. John - massive confusion here. IR is not heat for starters. Heat is energy being transferred by conduction between bodies at different temperatures. IR is energy as electromagnetic radiation. A CO2 molecule DOES absorbs radiation only in certain frequencies. It is anything but "clear" that it does otherwise. However, the atmosphere is also warmed by conduction. A molecule excited by absorption "heats" other molecules by collision. The CO2 molecule will also gain energy by collision with other molecules. The temperature of the atmosphere reflects both processes.
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  43. Also, yes, the atmosphere emits radiation in approximately the spectrum of the Planck's Law for a blackbody radiator (modified by the gas absorption bands).
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  44. I'd like to point out that carbon fibers do not really decompose in a short time. To use these in construction and such would be preferable to many other materials.
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  45. Re:#8.sleepership

    You have seen the future we are currently headed for, and it is very frightening indeed. The following extract from your comment on my article is insightful:

    “Was the heat the planet experienced this summer from 1980 C02 or from recently? If from 1980- when CO2 was just passing 350ppm- then we are in deep deep trouble when today's levels overcome the 'inertia' around the year 2040”

    A deep political problem at the moment is that the majority of our politicians see the current warming of 0.8 C (if they concede there is any connection to CO2 at all) as being related to the current atmospheric concentration. The equilibrium temperature rise for 390 ppm is in fact at least 1.4 C, so we are only part way there. The stated goal of the Copenhagen Accord of keeping global warming below 2 C is looking increasingly difficult to achieve.

    The only ray of hope is that the oceans have not yet absorbed all of this heat. They will absorb it, and the surface temperature will rise as projected, if the current energy imbalance is not reduced. We need not only to move rapidly to a near-zero carbon economy – we need to remove the bulk of the CO2 emitted from 1750 up till now. That will require either carbon sequestration on an industrial scale, or geoengineering.
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  46. Question: Did the economic recession in the 1930s contribute much to the mid 20th century cooling, as there is this delay?
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  47. “Nothing you've posted here would lead anyone to not invest in mitigation and adaption.”

    The aim of the actions already adopted in Kyoto was that the cost of fighting the AGW, ONLY (and solely) suffered final consumers (therefore: "normal" people), so that the producers of energy - due to rising costs - not moved their production to countries where there is no this "struggle."

    „As usual, you're cherrypicking ...”

    This is not true. Indeed, my aim was not to summarizing the work of the authors - which I cited. Everyone knows that of teams the authors - cited the work (especially the second and third) is an “avowed” great proponents of the theory of AGW. If, however, and they have such fundamental questions ...
    (And that was my goal - to submit questions - I hope not omitted any of their doubts - because only then - if I ignored this question - it would be "cherrypicking").

    For example, does the concentration of CO2 in the atmosphere will increase - for whatever reason - an additional 20 or 200 ppmv in the XXI century must be the great importance - what specific actions we take. Being a huge difference - in the context of chaos theory - "the wings of a butterfly" - indeed fundamental.

    These questions show that it really practically nothing (sufficiently accurately) do not know what will happen - for 40 years - from "our" CO2.
    Instead, there are serious reasons for that, not only in the Himalayan glaciers will melt by at least 300 years. In one word: "clock" - almost certainly - “not ticking "...

    Such a large number of papers of supporters of the theory of AGW, containing such a large question - written in recent times, is probably the result of appeal (2008 - The IPCC Must Maintain Its Rigor) Susan Solomon (real boss section "of science," the IPCC):
    “The climate system continues to change and science continues to improve, so policy must be kept current with our best understanding. Reformulating the science/policy interface should be considered and be open to change but must acknowledge lessons from the past. ...” “... if a rigorous scientific basis is to continue to inform the growing challenge of decision-making on climate change.”
    In 2010, Solomon does not know (but) nothing concrete (sufficiently accurately) about-at least - 1 / 3 warming - Guardian: “She said it was not clear if the water vapour decrease after 2000 reflects a natural shift, or if it was a consequence of a warming world. If the latter is true, then more warming could see greater decreases in water vapour, acting as a negative feedback to apply the brakes on future temperature rise.” “It shows that we shouldn't over-interpret the results from a few years one way or another.

    Korhola: “Decision-makers should make sensible choices regarding the overall benefits in the environment of UNCERTAINTY.”

    Rather than pay for the synthetic tree CO2 removes, I will pay for research such as thermo-nuclear fusion, or efficient energy storage in solar and wind power (in the periods when they do not produce energy) - it is always useful (for example, here is an interesting use of the thermal inertia of the usual molten salt).
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  48. @Arkadiusz: first, you should really stick to simple sentence, as your English does not appear to be strong enough to form complex sentences without making them confusing (non-English speaker, here).

    Second, you make a couple of puzzling statements:

    "For example, does the concentration of CO2 in the atmosphere will increase - for whatever reason - an additional 20 or 200 ppmv in the XXI century must be the great importance - what specific actions we take. Being a huge difference - in the context of chaos theory - "the wings of a butterfly" - indeed fundamental."

    Chaos theory and the Butterfly effect have little to do with long-term trends and the clear effects of additional CO2 in the atmosphere. You seem to be implying (I may be wrong, for that paragraph is unclear) that more CO2 simply means more uncertainty in the resulting effect. That is not true, and seems to be a misunderstanding of what Chaos Theory is about.

    "These questions show that it really practically nothing (sufficiently accurately) do not know what will happen - for 40 years - from "our" CO2."

    Quantify "sufficiently accurately", please. Just because we don't have exact predictions doesn't mean we can't say it will be warmer using a climate sensitivity value of about 3C.

    "Instead, there are serious reasons for that, not only in the Himalayan glaciers will melt by at least 300 years. In one word: "clock" - almost certainly - “not ticking "."

    I don't know what you're trying to say, here. As I said earlier, keep to short, factual sentences. Are you implying that there is no cause for alarm and therefore we shouldn't be worried because we have plenty of time to wait and see? That sounds terribly irresponsible.

    "If the latter is true, then more warming could see greater decreases in water vapour"

    I know this is quoted from an article, but it's important to note this isn't directly attributed to Solomon. In fact, it seems to be an extrapolation made by the journalist, and one that appears extremely unlikely. Warmer world = more water vapor over the long run.

    "Rather than pay for the synthetic tree CO2 removes, I will pay for research such as thermo-nuclear fusion, or efficient energy storage in solar and wind power (in the periods when they do not produce energy) - it is always useful (for example, here is an interesting use of the thermal inertia of the usual molten salt)."

    Okay, I first thought your mention of the synthetic tree was a image representing all CO2 mitigation efforts, but now you seem to say it is a real artefact? I'm confused.

    Efficient energy storage for solar and wind (using molten salt, for example) *are* ways to mitigate CO2 emmissions by lowering our use of fossil fuels. As for nuclear fusion, I'm all for it, but it may still take decades to get something that requires less energy to control than it produces...however, there's nothing preventing us from pursuing that research *in addition* to mitigation efforts, right?

    Again, sorry if I misunderstood some of your post.
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  49. #47 Arkadiusz Semczyszak

    If, however, and they have such fundamental questions ...(And that was my goal - to submit questions - I hope not omitted any of their doubts - because only then - if I ignored this question - it would be "cherrypicking").

    Of course it's cherrypicking. In addition to ignoring the authors' conclusions, you also ignored the fact that the "uncertainties" to which they refer at the beginning of their paper are precisely what their paper tries to address. That's why they say, "Here we address these questions [i.e., these uncertainties] by presenting an observationally based reconstruction of the spatially resolved, time-dependent history of anthropogenic carbon in the ocean over the industrial era."

    In other words, you're treating the paper's initial acknowledgment of existing uncertainty as the take-away message of their paper, which is an absurd way to approach the matter. Scientists are trained to communicate in a measured way, and there's nothing clever or rigorous about the "skeptical" stunt of using this basic convention of scientific discourse as a weapon against science itself.

    The intellectual pathology that sees uncertainty about AGW as positive is a whole other matter. (Where uncertainty exists, things can also be worse than we expect.)

    So yeah, that'd be cherrypicking, undertaken in defense of a position that's logically incoherent.
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  50. Since the launching of the USS Nautilus in 1954, nuclear submarines have plied the depths of the world’s oceans. My working assumption is that these vessels collected a wealth of information about the temperature of the lower layers of the global ocean system.

    I also acknowledge that the data collected by the fleets of nuclear submarines is highly classified.

    Notwithstanding the classified nature of the data, wouldn’t it make sense for the IPCC to establish a special committee to discuss this matter with the governments of those countries with nuclear submarine fleets?

    Perhaps there is way for the data to be made available without compromising national security concerns.

    The stakes are high!. It’s worth a try.
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