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Climate Hustle

Trenberth on Tracking Earth’s energy: A key to climate variability and change

Posted on 12 July 2011 by Kevin Trenberth

Energy and Climate

Climate change is very much involved with energy, most commonly in the form of heat but other forms of energy are also important. Radiation comes in from the sun (solar radiation at short wavelengths), and every body radiates according to its temperature (proportional to the fourth power of absolute temperature), so that on Earth we, and the surface and atmosphere radiate at infrared wavelengths. 

Weather and climate on Earth are determined by the amount and distribution of incoming radiation from the sun.  For an equilibrium climate, global mean outgoing longwave radiation (OLR) necessarily balances the incoming absorbed solar radiation (ASR), but with redistributions of energy within the climate system to enable this to happen on a global basis.  Incoming radiant energy may be scattered and reflected by clouds and aerosols (dust and pollution) or absorbed in the atmosphere.  The transmitted radiation is then either absorbed or reflected at the Earth’s surface. Radiant solar (shortwave) energy is transformed into sensible heat (related to temperature), latent energy (involving different water states), potential energy (involving gravity and altitude) and kinetic energy (involving motion) before being emitted as longwave infrared radiant energy.  Energy may be stored, transported in various forms, and converted among the different types, giving rise to a rich variety of weather or turbulent phenomena in the atmosphere and ocean.  Moreover the energy balance can be upset in various ways, changing the climate and associated weather.

Hence the incoming radiation may warm up the ground or any object it hits, or it may just go into drying up surface water. After it rains and the sun comes out, the puddles largely dry up before the temperature goes up.   If energy is absorbed it raises the temperature.  The surface of the body then radiates but also loses heat by transfer through cooler winds or by evaporative cooling.  Some energy gets converted into motion as warm air rises and cold air sinks, and this creates winds and thus kinetic energy, which gets dissipated by friction.  Over oceans the winds drive ocean currents. 

The differential between incoming and outgoing radiation: the net radiation is generally balanced by moving air of different temperature and moisture content around.  Air temperature affects density as warmer air expands and thus it takes up more room, displacing cooler air, thereby changing the air in a column whose weight determines the surface pressure.  Consequently, this sets up pressure differences that in turn cause winds, which tend to blow in such a way as to try to offset the temperature differences. The Earth’s rotation modifies this simple picture. A result is that southerlies are warm in the northern hemisphere and northerlies are cold.  And so we get weather with clouds and rain in all of its wondrous complexity.

The changing seasons illustrate what happens as the sun apparently moves across the equator into the other hemisphere.  In summer some excess heat goes into the ocean, which warms up reaching peak values about the equinox, and in winter the land cools off but heat comes out of the oceans and this is carried onto land, and so oceans moderate the seasonal climate variations.  Much of the exchange involves water evaporating and precipitating out, and thus the hydrological cycle.

The same can happen from year to year: heat can accumulate in the ocean and then later be released, leading to warmer spells and cooler spells.  This commonly happens in the tropical Pacific and gives rise to the El Niño phenomenon.  El Niño is the warm phase in the tropical Pacific while La Niña is the cool phase.  During and following an El Niño there is a mini global warming as heat comes out of the ocean, while during La Niña, heat tends to get stored in the ocean.  The El Niño cycle is irregular but has a preferred time scale of 3 to 7 years.

Ocean heat storage can last longer: for decades or centuries and inevitably involves ocean currents and the much deeper ocean.  In the North Atlantic, cold waters sink and move equatorward at depth while the Gulf Stream at the surface takes warmer waters polewards, creating an overturning circulation that can also involve density changes in the ocean associated with both temperature and salt (the thermohaline circulation). Salty water is denser. Nonetheless, much of the ocean overturning circulation is wind driven. The overturning may involve the ocean down to several kilometers and can take many centuries to complete a cycle.

As well as the ocean taking up heat, heat can be lost by forming ice, as glaciers, ice caps, or major ice sheets (Greenland and Antarctica) on land, or as sea ice. Extra heat can melt this ice and may contribute to sea level rise if land ice melts.  Surface land can also absorb a small amount of heat but not much and not to great depths as it relies on conduction to move heat through the land unless water is flowing. Land energy variations occur mostly in the form of water or its absence, as heat goes to evaporate surface water.  Highest temperatures and heat waves typically occur in droughts or deserts.

The atmosphere can not hold much heat and is dependent for its temperature on links to the underlying surface through conduction and thermals, convection, and radiation, as well as the wind in moving it around.

The global energy budget

In the past, we (Kiehl and Trenberth 1997) provided estimates of the global mean flow of energy through the climate system and presented a best-estimate of the energy budget based on various measurements and models, by taking advantage of the fact that energy is conserved.  We also performed a number of radiative computations to examine the spectral features of the incoming and outgoing radiation and determined the role of clouds and various greenhouse gases in the overall radiative energy flows. At the top-of-atmosphere (TOA) values relied heavily on observations from the Earth Radiation Budget Experiment (ERBE) from 1985 to 1989, when the TOA values were approximately in balance. 

Values are given in terms of Watts per square meter. The incoming radiation is about 342 W m-2.  But there are about 5.1x1014 square meters for the surface area and so the total incoming energy is about 174 PetaWatts (=1015 watts, and so 174 with 15 zeros after it or 174 million billion).  About 30% is reflected back to space and so about 122 PW flows through the climate system.  For comparison, the biggest electric power plants are of order 1000 MegaWatts, and so the natural flow of energy is 122 million of these power plants.  If we add up all of the electric energy generated and add in the other energy used by humans through burning etc, it comes to about 1/9000th of the natural energy flow.  Hence the direct effects of human space heating and energy use are small compared with the sun, although they can become important very locally in cities where they contribute to the urban heat island effect.

New observations from space have enabled improved analyses of the energy flows. Trenberth et al. (2009) have updated the earlier global energy flow diagram (Fig. 1) based on measurements from March 2000 to November 2005, which include a number of improvements. We deduced the TOA energy imbalance to be 0.9 W m-2, where the error bars are ±0.5 W m-2 based on a number of estimates from both observations and models.

Figure1

Figure 1. The global annual mean Earth’s energy budget for 2000 to 2005 (W m–2). The broad arrows indicate the schematic flow of energy in proportion to their importance.  From Trenberth et al (2009).

The net energy incoming at the surface is 161 W m-2, and this is offset by radiation (63), evaporative cooling (80), and direct heating of the atmosphere through thermals (17).  Consequently, evaporative cooling and the resulting water cycle play a major role in the energy balance at the surface, and for this reason, storms are directly affected by climate change. The biggest loss at the surface is from long-wave radiation but this is offset by an almost as big downward radiation from greenhouse gases and clouds in the atmosphere to give the net of 63 units. 

Updates included in this figure are revised absorption in the atmosphere by water vapor and aerosols. The direct transfer of heat has values of 17, 27 and 12 W m-2 for the globe, land and ocean, and even with uncertainties of 10%, the errors are only order 2 W m-2. There is widespread agreement that the global mean surface upward longwave (LW) radiation is about 396 W m-2, which is dependent on the skin temperature and surface emissivity.

Global precipitation should equal global evaporation for a long-term average, and estimates are likely more reliable of the former. However, there is considerable uncertainty in precipitation over both the oceans and land.  The latter is mainly due to wind effects, undercatch and spatial coverage, while the former is due to shortcomings in remote sensing.  The downward and net LW radiation were computed as a residual and compared to various estimates which tend to be higher but all involve assumptions and models. The correct depiction of low clouds is a continuing challenge for models and is likely to be a source of model bias in downward LW flux. For example, there are sources of error in how clouds overlap in the vertical and there is no unique way to treat the effects of overlap on the downward flux.

The new observations from space have enabled improved analyses of the energy flows, their variations throughout the annual cycle, for land versus ocean, as a function of location, and also over a number of years. There is an annual mean transport of energy by the atmosphere from ocean to land regions of 2.2±0.1 PW primarily in the northern winter when the transport exceeds 5 PW.  It is now possible to provide an observationally based estimate of the mean and annual cycle of ocean energy, mainly in the form of ocean heat content. 

Note that the sum of all the values at the TOA and at the surface in the figure leaves an imbalance of 0.9 W m-2, which is causing global warming.  As carbon dioxide and other greenhouse gases increase in the atmosphere, there is initially no change in the incoming radiation, but more energy is trapped and some is radiated back down to the surface. This decreases OLR and leads to warming.  At the surface the warming raises temperatures and thus increases the surface radiation, but there is still a net amount of energy that partly goes into heating the ocean and melting ice, and some of it goes into increasing evaporation and thus rainfall.  To achieve an energy balance, the vertical structure of the atmosphere changes, and the radiation to space ultimately comes from higher regions that were originally colder.  In that sense, the figure is misleading because it does not show the vertical structure of the atmosphere or how it is changing.

There is often confusion about how the greenhouse effect works. Greenhouse gases are those with more than two atoms, and water vapor is most important (H2O).  But water has a short lifetime in the atmosphere of 9 days on average before it is rained out. Carbon dioxide (CO2), on the other hand, has a long lifetime, over a century, and therefore plays the most important role in climate change while water vapor provides a positive feedback or amplifying effect: the warmer it gets, the more water vapor the atmosphere can hold by about 4% per degree Fahrenheit.  Most of the atmosphere is nitrogen (N2) and oxygen (O2) and does not play a role in the greenhouse effect.  Oxygen does play an important role through ozone (O3) though, especially in the stratosphere where an ozone layer forms from effects of ultraviolet light. Ozone is not well mixed throughout the atmosphere as it has a short lifetime in parts of the stratosphere, and in the lower atmosphere its life is measured in months as it plays a role in oxidation.

The air is otherwise well mixed up to about 80 km altitude and heavier gases like carbon dioxide do not settle out owing to all the turbulent motions, convection, and so on. Also the other long lived greenhouse gases are well mixed and connect to the non-greenhouse gases with regard to temperature.  Air near the surface has a temperature not much less than the surface on average, and therefore it radiates back down with almost as much energy as came up from below.  But because the air gets thinner with height, its temperature falls off, and air is a lot colder at 10 km altitude where ‘planes typically fly. This air therefore radiates less both up and down, and the net loss to space is determined by the vertical temperature structure of the atmosphere and the distribution of greenhouse gases.

Changes in energy balance over the past decade

With the new measurements from space, variability in the net radiative incoming energy at the top-of-atmosphere (TOA) can now be measured very accurately. Thus a key objective is to track the flow of anomalies in energy input or output through the climate system over time in order to address the question as to how variability in energy fluxes is linked to climate variability.  The main energy reservoir is the ocean (Fig. 2 below), and the exchange of energy between the atmosphere and ocean is ubiquitous, so that heat once sequestered can resurface at a later time to affect weather and climate on a global scale.  Thus a change in the energy balance has consequences, sooner or later, for the climate.  Moreover, we have observing systems in place that nominally can measure the major storage and flux terms, but due to errors and uncertainty, it remains a challenge to track anomalies with confidence.

Figure2

Figure 2. Energy content changes in different components of the Earth system for two periods (1961–2003 and 1993–2003). Blue bars are for 1961 to 2003; burgundy bars are for 1993 to 2003. Positive energy content change means an increase in stored energy (i.e., heat content in oceans, latent heat from reduced ice or sea ice volumes, heat content in the continents excluding latent heat from permafrost changes, and latent and sensible heat and potential and kinetic energy in the atmosphere). All error estimates are 90% confidence intervals. No estimate of confidence is available for the continental heat gain. Some of the results have been scaled from published results for the two respective periods.  From (IPCC 2007, Fig. TS.15 and Fig. 5.4).

A climate event, such as the drop in surface temperatures over North America in 2008, is often stated to be due to natural variability, as if this fully accounts for what has happened.  Aside from weather events that primarily arise from instabilities in the atmosphere, natural climate variability has a cause.  Its origins may be external to the climate system: a change in the sun, a volcanic eruption, or Earth’s orbital changes that ring in the major glacial to interglacial swings.  Or its origins may be internal to the climate system and arise from interactions among the atmosphere, oceans, cryosphere and land surface, which depend on the very different thermal inertia of these components. 

El Niño

As an example of natural variability, the biggest El Niño in the modern record by many measures occurred in 1997-98. Successful warnings were issued a few months in advance regarding the unusual and disruptive weather across North America and around the world, and were possible in part because the energy that sustains El Niño was tracked in the ocean by a new moored buoy observing system in the Tropical Pacific.  Typically prior to an El Niño, in La Niña conditions, the cold sea waters in the central and eastern tropical Pacific create high atmospheric pressure and clear skies, with plentiful sunshine heating the ocean waters.  The ocean currents redistribute the ocean heat which builds up in the tropical western Pacific Warm Pool until an El Niño provides relief.  The spread of warm waters across the Pacific in collaboration with changing winds in turn promotes evaporative cooling of the ocean, moistening the atmosphere and fueling tropical storms and convection over and around the anomalously warm waters. The changed atmospheric heating alters the jet streams and storm tracks, and influences weather patterns for the duration of the event.

The central tropical Pacific SSTs are used to indicate the state of El Niño, as in Fig. 3 presented below.  In 2007-08 a strong La Niña event, that spilled over to the 2008-09 northern winter, had direct repercussions for cooler weather across North America and elsewhere.  But by June 2009, the situation had reversed as the next El Niño emerged and grew to be a moderate event, with temperatures in the top 150 m of the ocean above normal by as much as 5°C across the equatorial Pacific in December 2009.  Multiple storms barreled into Southern California in January 2010, consistent with expectations from the El Niño. The El Niño continued until May 2010, but abruptly reversed to become a strong La Niña by July 2010.

Figure3

Figure 3.  Recently updated net radiation (RT=ASR-OLR) from the TOA http://ceres.larc.nasa.gov/products.php?product=EBAF.  Also shown is the Niño 3.4 SST index (green) (left axis); values substantially above the zero line indicate El Niño conditions while La Niña conditions correspond to the low values. The decadal low pass filter is a 13 term filter making it similar to a 12-month running mean.  Units are Wm-2 for energy and deg C for SST.

We can often recognize these changes once they have occurred and they permit some level of climate forecast skill. But a major challenge is to be able to track the energy associated with such variations more thoroughly: where did the heat for the 2009-10 El Niño actually come from?  Where did the heat suddenly disappear to during the La Niña?  Past experience suggests that global surface temperature rises at the end of and lagging El Niño, as heat comes out of the Pacific Ocean mainly in the form of moisture that is evaporated and which subsequently rains out, releasing the latent energy. 

The values and patterns of SSTs in the northern summer of 2010 undoubtedly influenced the extremes of weather, from excessive rains and flooding in China, India and Pakistan, the active hurricane season in the Atlantic, and record breaking rains in Colombia. Later the high SSTs north of Australia contributed to the Queensland flooding.  The La Niña signature has also been present across the United States in the spring of 2011 with the pattern of drought in Texas and record high rains further to the north, with flooding along the Mississippi and deadly tornado outbreaks.

Anthropogenic climate change

The human influence on climate, arising mostly from the changing composition of the atmosphere, also affects energy flows. Increasing concentrations of carbon dioxide and other greenhouse gases have led to a post-2000 imbalance at the TOA of 0.9±0.5 W m-2 (Trenberth et al. 2009) (Fig. 1), that produces “global warming”, or more correctly, an energy imbalance.  Tracking how much extra energy has gone back to space and where this energy has accumulated is possible, with reasonable closure for 1993 to 2003; see Fig. 2. Over the past 50 years, the oceans have absorbed about 90% of the total heat added to the climate system while the rest goes to melting sea and land ice, and warming the land surface and atmosphere. Because carbon dioxide concentrations have further increased since 2003 the amount of heat subsequently being accumulated should be even greater. 

While the planetary imbalance at TOA is too small to measure directly from satellite, instruments are far more stable than they are absolutely accurate.  Tracking relative changes in Earth’s energy by measuring  solar radiation in and infrared radiation out to space, and thus changes in the net radiation, seems to be at hand.  This includes tracking the slight decrease in solar insolation from 2000 until 2009 with the ebbing 11-year sunspot cycle; enough to offset 10 to 15% of the estimated net human induced warming.

In 2008 for the tropical Pacific during La Niña conditions, extra TOA energy absorption was observed as expected; see Fig. 3. The Niño 3.4 SST index is also plotted on this figure and the slightly delayed response of the OLR to cooler conditions in the record and especially in 2008 is clear. However, the decrease in OLR with cooler conditions is accompanied by an increase in ASR as clouds decrease in amount, leaving a pronounced net heating (>1.5 W m-2) of the planet in the cooler conditions.  And so this raises the question as to whether a coherent perspective that accounts for both TOA and ocean variability can be constructed from the available observations.  But ocean temperature measurements from 2004 to 2008 suggested a substantial slowing of the increase in global ocean heat content, precisely during the time when satellite estimates depict an increase in the planetary imbalance.

Since 1992, sea level observations from satellite altimeters at millimeter accuracy reveal a global increase of ~3.2 mm yr-1 as a fairly linear trend, although with two main blips corresponding to an enhanced rate of rise during the 1997-98 El Niño and a brief slowdown in the 2007-08 La Niña.  Since 2003, the detailed gravity measurements from Gravity Recovery and Climate Experiment (GRACE) of the change in glacial land ice and water show an increase in mass of the ocean. This so-called eustatic component of sea level rise may have compensated for the decrease in the thermosteric (heat related expansion) component.  However, for a given amount of heat, 1 mm of sea level rise can be achieved much more efficiently – by a factor of 40 to 70 typically – by melting land ice rather than expanding the ocean.  So although some heat has gone into the record breaking loss of Arctic sea ice, and some has undoubtedly contributed to unprecedented melting of Greenland and Antarctica, these anomalies are unable to account for much of the measured TOA energy (Fig. 4).   This gives rise to the concept of “missing energy” (Trenberth and Fasullo 2010). 

Figure4

Figure 4.  The disposition of energy entering the climate system is estimated.  The observed changes (lower panel; Trenberth and Fasullo 2010) show the 12-month running means of global mean surface temperature anomalies relative to 1901-2000 from NOAA (red (thin) and decadal (thick)) in °C (scale lower left), carbon dioxide concentrations (green) in ppmv from NOAA (scale right), and global sea level adjusted for isostatic rebound from AVISO (blue, along with linear trend of 3.2 mm/yr) relative to 1993, scale at left in millimeters).  From 1992 to 2003 the decadal ocean heat content changes (blue) along with the contributions from melting glaciers, ice caps, Greenland, Antarctica and Arctic sea ice plus small contributions from land and atmosphere warming (red) suggest a total warming for the planet of 0.6±0.2 W m-2 (95% error bars).  After 2000, preliminary observations from TOA (black) referenced to the 2000 values, as used in Trenberth and Fasullo (2010), show an increasing discrepancy (gold) relative to the total warming observed (red).  The quiet sun changes in total solar irradiance reduce the net heating slightly but a large energy component is missing (gold). Adapted from Trenberth and Fasullo (2010). The monthly global surface temperature data are from NCDC, NOAA: http://www.ncdc.noaa.gov/oa/climate/research/anomalies/index.html ; the global mean sea level data are from AVISO satellite altimetry data: http://www.aviso.oceanobs.com/en/news/ocean-indicators/mean-sea-level/ ; and the Carbon dioxide at Mauna Loa data are from NOAA http://www.esrl.noaa.gov/gmd/ccgg/trends/.

To emphasize the discrepancy, Fig. 5 presents an alternative version of Fig. 2 for 1992 to 2003, as a contrast to 2004 to 2008.  The accounting for all terms and the net imbalance is compatible with physical expectations and climate model results, with the net imbalance about 0.7 W m-2 at TOA for 1992 to 2003.  However, for the 2004 to 2008 period, the decrease in solar radiation associated with the sunspot cycle and the quiet sun in 2008 contributed somewhat, but the Ocean Heat Content (OHC) change is a lot less than in the previous period and a residual imbalance term: the missing energy, is required.

Figure5

Figure 5.  The energy entering the climate system is estimated for the various components: warming of the atmosphere and land, ocean heat content increase, melting of glaciers and ice caps (land ice), melting of the major ice sheets (Greenland and Antarctica), and changes in the sun. For 1993 to 2003 these are summed to give the total which is equivalent to about 0.7 W m-2.  For 2004-2008, TOA measurements are used to provide an increment to the total based on comparisons with 2000-2003, and the quiet sun has contributed, but the sum is achieved only if a spurious residual is included. Units are 1020 Joules/year.

Further inroads into this problem will no doubt become possible as datasets are brought up to date and refined.  In the meantime, we have explored the extent to which this kind of behavior occurs in the latest version of the NCAR climate model.  In work yet to be published (it is submitted), we have found that energy can easily be “buried” in the deep ocean for over a decade.  Further preliminary exploration of where the heat is going suggests that it is associated with the negative phase of the Pacific Decadal Oscillation and/or La Niña events. 

Clearly, tracking energy and how and where it is stored, and then manifested as high SSTs which in turn affect subsequent climate is an important thing to do.

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Comments 151 to 200 out of 270:

  1. Muon, I think you're being generous. What I see instead of a race car is a pile of car parts, washing machine parts, legos, a picture of a race car, a few bananas, and a yo-yo--all of which has the label "it's a race car, you idiots" attached to it.

    "The 'system' is working one way or another."

    Oh my.
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  2. While Doug Cotton @150 clearly shows his colours as a man for whom is conclusion that the greenhouse effect does not exist is far more important than any scientific evidence or reasoning, it is important to understand what is wrong with his claims.



    Above is a IR spectrum from Earth at the top of the atmosphere. You can clearly see that the spectrum follows the curve for a black body radiation of about 270 degrees, but with some notches taken out. The most important notches are the large one at about a wave number of 700 due to CO2, a shallow but extensive notch at lower wave numbers due to H2O, another moderately deed notch at a wave number of about 1000 due to ozone, and another shallow extensive notch above wavenumbers of 1300 due to methane and H2O.

    The actual value of the curve depends on the surface temperature of the region of the Earth over which the observation was made, as is illustrated by this NASA graphic:



    It is not often appreciated by deniers and "skeptics", but these observations are absolute proof that green house gases warm the Earth.

    The reason for that is simple. In each of these observations, the total energy radiated from the Earth at the top of the atmosphere is equal to the area under the curve. It is obvious that the notches introduced to the curve by the absorption of IR radiation reduce the area under the curve. But if they reduce the area under the curve, ipso facto, they reduce the total energy radiated to space. As, on average the energy radiated to space must equal the energy received from the sun, if the area under the curve is reduced by the absorption of IR radiation by green house gases, then the area under those parts of the curve in which IR radiation is not absorbed must increase in order that the same overall energy output is obtained. And that can only be achieved by the surface of the planet, the source of the rest of the radiation, warming.

    What ever your thoughts on the green house effect may be, once these observations were made the only way to deny its existence was to deny the truth of the three governing laws of black body radiation that relate radiation to temperature - laws as well confirmed as anything in science.

    But what of DougCotton's scenario?

    If all the Sun's radiation intercepted by the Earth was absorbed by the surface, and there were no greenhouse gases, then the average observed IR spectrum from the Earth would be a smooth black body curve with no notches from IR absorption, and it would show a surface temperature of 255 degrees K, the temperature required for a black body curve to radiate the 240 W/m^2 average energy received from the Sun after albedo effects. (Actually it would show different values at different latitudes, but the values would average out at 240 W/m^2.)

    If there was not CO2 or water vapour in the atmosphere, but the atmosphere still absorbed 78 W/m^2 as shown in the diagram in the main article, what would happen? Well there would still be one molecule capable of radiating IR radiation, ozone. And ozone would need to radiate most of that 78 W/m^2. Somebody observing from space would then see something very interesting. They would see a standard black body curve from the surface showing a surface temperature of around 230 degrees K, with a massive spike of radiation from the ozone.

    This situation, in which the green house gas is cooling the atmosphere is well known to atmospheric physics, and sometime occurs on Earth over Antarctica, as in the following spectrum (see spectrum b):



    (Also see the second spectrum in (c) (Tropical Western Pacific) where the thunderstorm anvil shows a massive warming effect, reducing the effective radiation to space from a black body curve of around 290 K to that for 210 K, which is slightly compensated for by CO2. That is, in the absence of CO2 the thunderhead anvil would have an even stronger warming effect.)

    It is now clear what we should look for if CO2 had a typically cooling effect as claimed by DougCotton and Jonicol - the spectrums should consistently show a spike from CO2 instead of (as they typically show) the deep trough we have come to expect.

    Finally, let me point out the massive hubris of DougCotton. Atmospheric physicists know all of the facts I have pointed out and on which he bases his theory. After all, it is from them that I learnt those facts. They not only know those fact, but they have explored their consequences in the very detailed calculations and extensive sets of calculations that are called climate models, which have been tested against observation and shown a good fit between observation and predicted result (see 103 above). But DougCotton thinks his 200 word verbal argument is more likely to be true than the years of detailed analysis by climate scientists of the facts Doug has just learnt.

    Not even an Einstein would be likely to get correct on so little thought what the physicists have purportedly been getting wrong from so massive and careful an analysis. Of course, a true Einstein would not (an Einstein was not) be so prideful in their own reasoning.
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  3. One thing about DC's "insight" - he is almost onto the reason why increasing CO2 causes cooling of the upper stratosphere - the smoking gun of GHG warming.
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  4. Tom#152: "But DougCotton thinks his 200 word verbal argument is more likely to be true than the years of detailed analysis by climate scientists of the facts Doug has just learnt."

    I doubt that Mr. Cotton actually learned anything from this encounter.

    What we witnessed was a very revealing look into the denier's mindset. He has a preconceived notion; neither fact nor theory will sway him. When shown that he self-contradicts, he ignores the error -- and then boasts of his logic. When challenged to produce data, he cannot -- and it does not bother him. When shown that his model is nonsense that violates all accepted theory, he makes up even more nonsense -- and congratulations himself for his cleverness.

    Very telling is the fact that not one of the regular skeptics here chimed in to support his position. Also telling is that not one of the skeptics here voluntarily said something to the effect of 'I have objections to the greenhouse effect, but I can recognize that you're way off base.'

    I think, however, that this encounter validates the strategy of powerful refutation of one specific point at a time. If nothing else, it produced some very clear explanation of what the actual science says. But there is a clear difference between working with those college physics students and someone like Cotton: the students actually want to learn.

    John Wooden, a legendary US college basketball coach put it this way: It's what you learn after you know it all that counts.
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  5. saddenp @153, a very good point. For anyone visiting this site who want's to learn, the UV energy absorbed by O2 and O3 in the stratosphere is dissipated as IR radiation by CO2 and O3 (ozone). Thus, in the stratosphere increased CO2 does have a cooling effect. This shows up in the graphs in 152 as the central spike in both the CO2 and O3 troughs, produced by the radiation in the stratosphere.
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  6. All right - one more reply ...

    ( -Snip -)

    But this is not about personalities. My motives have never been other than to try to find reasons for the clear-cut reduction in warming that has been observed since 2003 - and to play whatever part I can in helping to calm the unnecessary turmoil that global warming predictions have engendered.
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    Response:

    [DB] Alright, now that you've had your say Mr. Cotton, you have no purpose here.  You are not here to learn: others have already pointed out the numerous fallacies and errors you have made thus far.  Indeed, the mistakes and gaffes you commit are legion in this comment alone. So learning on your part is not your goal here.  Please take your litanyous Gish Gallop elsewhere.

    If you wish to have a rational dialogue and actually begin to learn a bit about climate science, this is the place.  Thousands of posts exists with attendant comment threads, all with links to the primary literature.  You would do well to read at least some of it before you attempt to teach those who already have.

  7. DougC#156: "My motives have never been other than to try to find reasons... "

    Thanks, you've confessed at last. Your 'motives' should have been first to understand the science and only then formulate your conclusions.

    Given this admission, any 'true skeptics' here should be speaking up about now. ... anyone? Buehler?
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  8. If that has been your motive, Doug, you've gone about it in a very odd way. You're not taking into account basic science that engineering of every kind depends on. I understand you've spent a lot of time writing your site, and you've invested yourself in your ideas. I'm reminded of one of my students who spent weeks of skull sweat hashing out an argument only to find out that he had failed to consider the strongest counterargument. He spent three or four days trying to wriggle out of addressing the problem (which clearly required a re-write of the ten-page paper). He tried bargaining with me ("what if I just tack on a paragraph at the end -- what grade will that get me?"). He tried to buy a balance through extra credit (Umm . . . No). I did end up allowing him all of finals week to do the re-write, and to his credit he did a fair job of re-thinking his argument.

    Of course, you seem to have more at stake than my student. Your errors--the fundamentals upon which the currently crooked house is built--are public. Swallowing one's pride is difficult in some circumstances, but it should never be difficult when it results in a greater level of integrity. One thing I am certain of: if you ask questions and discuss responses without the subtext that the other participants are frauds, hoaxers, or idiots, no one here will bring forth a quantum of ridicule.

    For example, you finally arrive at a motivation in your most recent comment: a decrease in the rate of warming since 2003. Unfortunately, you buried that chocolate chip in a hard dough moistened by piss and vinegar. Perhaps it's understandable given the rhetoric that's been thrown at you. Perhaps. If you're still interested in discussing the science, start on a new tack. Rather than presenting your physical model as absolute and unquestionable truth, ask questions and discuss responses. Assume nothing. Ask for evidence. Don't decrease the probability of anything without clear reason. Keep an open mind. Work on one thing at a time.

    If this all seems condescending, take a good long look at your posts, both here and elsewhere. And keep in mind the patience Tom and others (not all others) have shown you. Finally, keep in mind that the regulars here routinely have to deal with some truly nutty crap, and so patience can be in short supply when someone refuses to engage and tinges everything with a knowing smirk and the suggestion of fraud.
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  9. #152 Tom:

    I would have considered ozone a GH gas as at least some others do. I was painting a hypothetical scenario in which all gases that acted like GH gases (able to emit in the IR range) were absent. But even if you leave ozone up there, and just had O2 and N2 where we live, they would absorb incident UV at all altitudes and we would frizzle in the absence of GH gases here in the lower troposhpere.

    ( -Moderation Complaints Snipped- )
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    Response:

    [DB] If you wish to directly interact with Tom and the others by having actual dialogue (which involves asking questions, getting answers, pondering answers & asking more questions [which goes for either side]), then interact away.

    If you are going to ignore the feedback and correction of others & Gish Gallop away, then accept that moderation of comments is an accepted condition of participating in this Forum.  And moderation affects all, equally.  Defamation is not allowed (however, implying legal action such as you just did tells volumes about character).

    If you want to talk climate science, partake in the discussion and be welcome. 

    If you want a podium and a microphone, go away.

  10. #155 Tom:

    You stated:

    "the UV energy absorbed by O2 and O3 in the stratosphere is dissipated as IR radiation by CO2 and O3 (ozone). Thus, in the stratosphere increased CO2 does have a cooling effect."

    Is there any reason why could not also state

    "the UV energy absorbed by O2 in the troposphere is dissipated as IR radiation by CO2. Thus, in the troposphere increased CO2 does have a cooling effect." ?
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  11. #152 Tom:

    Three genuine questions this time:-

    (1) I have read several papers along the lines of your post (and do understand the reasoning) but I note references to temperatures around 275 deg.K, whereas NASA sea surface means are usually a little over 294 deg.K. Could you clarify the reason for the difference?

    (2) I would like from you a little more explanation of the conclusiom "the source of the rest of the radiation, warming." To explain why I am asking, suppose we note the temperature of, say, the top of the ocean in some location at 4am one day and then, after all the various iterations of the feedback cycle the next day, the surface of the water is warmed during the day and starts to radiate extra and, as it cools, "pushes up" the whole plot, still with its notches. What evidence do we then have from the plot that the ocean has not returned to the same initial temperature by 4am the next day?

    (3) What happened to the evaporation component, assuming the latent heat was released in the troposphere quickly that day?
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  12. Doug, you are asking some question that actually requires doing the maths - (and thus avoiding hand wavy answers). The place to start is Ramanathan and Coakley 1978. To see what that looks like when you do the calculations then look at Modtrans code pointed to earlier. You will note that this mathematical model is extremely successful at predicting power and spectrum of both OLR and DLR. An alternative formulation would need experimental confirmation at least as good.

    For more on why stratosphere cools but troposphere warms with increased CO2, try looking at here.
    Again, same underlying mathematics.
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  13. DougCotton @161:

    1) The first spectrum shows a black body radiation for the surface of about 275 K. As black body radiation, it is a function of the temperature and emissivity of the emitting source, in this case the surface, which indicates the surface at the particular location and time the spectrum was observed was about 275 degrees K (or 2 degrees C). Spectrums at other times and places will show different temperatures. For example, the Sahara spectrum (third image, part a) shows a black body radiation of approximately 325 degrees K (52 degrees C); that for Antarctica shows 180 degrees K (-93 degrees C); and those for the Tropical Western Pacific and Southern Iraq show 295 degrees K (23 degrees C).

    If you divided the Earth's surface up into equal cells of about 2 to 4 times the size of the instrument resolution, and took a spectrum for each cell, then determined a mean spectrum for the whole Earth, then the mean black body curve shown would be for approx 288 degrees K, and the area under the curve would be approx the same as the area under the curve of a smooth (no notches or peaks) 255 degree K black body curve.

    2) To quote the conclusion in full, so that it makes sense:

    " As, on average the energy radiated to space must equal the energy received from the sun, if the area under the curve is reduced by the absorption of IR radiation by green house gases, then the area under those parts of the curve in which IR radiation is not absorbed must increase in order that the same overall energy output is obtained. And that can only be achieved by the surface of the planet, the source of the rest of the radiation, warming."


    Consider, as a simple analogy, a water filled ballon. As water is uncompressible for normal pressure ranges, the volume of the balloon is constant. Therefore, if you press down on one part of the balloon, it will bulge out at other parts, of necessity. If it did not, the indentation from your pressing down would have resulted in a loss of volume.

    Returning to the spectrums, the area under the curve is the power output at the location measured. As indicated above, averaged over the Earth's surface, the area under the curve is the same as the area under a 255 degree black body curve. It must be, or else the energy coming in from the Sun will not equal the energy going out by IR radiation, and the Earth will be either heating or cooling to compensate.

    Because the area under the curve averaged over the globe is effectively a constant, if some part of the curve lies below the 255 degree black body curve, then other parts must lie above it to maintain the constant area. This is an exact analogy of the situation with the balloon.

    As it happens, the areas lying below the 255 degree curve do so because they are emitted high in the atmosphere by CO2. That means the areas emitted from the surface must lie above the 255 degree curve to compensate, and the only way they can do that is if the surface is warmer than 255 degrees K, on average.

    I have treated the averaged case because it is easier. It would be equally possible to treat each cell (see (1)) seperately, and determine the area of a black body curve having the same area under the curve as does the spectrum from that location and time. Any part of the observed spectrum lying below that curve represents greenhouse forcing, and needs to be compensated for by parts of the spectrum lying above the curve, ie, being warmer because of greenhouse forcing.
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  14. DougCotton @160, the atmosphere absorbs around 78 W/m^2 from the Sun, mostly as a result of H20 and aerosols (which each account for nearly 50% of the energy absorbed). Most of the rest of the energy absorbed is absorbed by O2 in the thermosphere, and O3 in the mesosphere and stratosphere.

    If we supposed that all of the energy absorbed by the atmosphere was absorbed in the lower 2 km of the atmosphere, that would represent just 16% of the energy absorbed by the surface at that level. The immediate effect of that would be to slightly warm the lower atmosphere with respect to the surface, thus causing conduction to be a net sink of atmospheric heat rather than a source. It would also cause precipitation to be reduced in the lower atmosphere resulting in energy from evapo-transpiration to be released higher in the atmosphere than it currently does. It would also increase the backradiation. Most importantly, it would increase the rate at which convection carries heat away from the surface and lower regions of the atmosphere. The net effect would be negligible.

    Importantly, the CO2 in the upper troposphere would still be much cooler than the surface. Consequently, CO2 radiation from the upper troposphere which escapes to space would be much weaker than the radiation from the surface (and the CO2 in the lower troposphere) that would have escaped to space if the upper tropospheric CO2 had been absent. Consequently, the net effect of the CO2 would still be to warm the surface.
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  15. Tom, thank you for your time in replying. I have read and understood your argument, and did in fact already know about what you have said. I will endeavour to explain what I believe to be the fallacy and why what you say "And that can only be achieved by the surface of the planet, the source of the rest of the radiation, warming" does not give reason for assuming that long-term warming is happening. My points are ...

    1) Obviously there have been times of cooling for several years, eg after 1960. Yet at those times there was CO2 in the atmosphere and that would have given a similar plot, complete with notches.

    2) We all have walked on hot sand or rocks, so we know the surface warms temporarily on hot days, and cools at night. So that is all your quoted sentence is actually confirming.

    3) You might as well just measure the inward and outward bound radiation at the top of the atmosphere, from a satellite I guess. In general, in regard to warming or cooling, it won't tell you any more than what you already know from temperature data.

    4) There can, however, be differences between (3) and what temperatures tell us due to build up or decline in potential (stored) energy, such as ice melting, water vapour forming by evaporation etc. So, unless we can quantify these factors over the time span measured, the information is useless. (A company cannot work out its sales from its purchases unless it knows opening and closing stock.)

    Just one other point, O2 absorbs at various altitudes - UV-A and UV-B higher up, but UV-C right down to the lower troposphere. In general, UV has much more energy than visible light, let alone IR as everyone here knows. (The O2 may become O3 in the process which is, of course, relatively unstable.) That energy will end up, after collisions, as photons both surface-bound and space-bound. (It has to, or the atmosphere would warm excessively in the long term.)

    Finally, feedback photons from CO2 to the surface, convert to heat and thence back to (nearly) full spectrum IR radiation, and so most will not be absorbed by CO2 on the second iteration, or perhaps the third etc. (Feedback is a multi-iteration process.) In the limit, all can get out regardless of the amount of CO2 - within reason - usually by, say, 4am the next morning. But if some heat in the oceans builds up in summer months, it then has winter to cool off - as we observe happens.
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  16. #162: scadenp: I'm reluctant to place much emphasis on that 1978 paper which acknowledges several limitations and short-comings of the models of the time. They had problems regarding critical lapse rates which implied these were overstated by the models, which they said were in need of improvement. My understanding is that improvements were (are still?) needed in the treatment of marine boundary layer clouds and tropical convective clouds.
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    Moderator Response: [Dikran Marsupial] The 1978 paper was suggested as a good place for you to start in gaining an understanding of the physics of climate and modelling. Of course there are limitations and there has been considerable progress in the last 30 years, however you need to start with the basics first. Your response is essentially a failure to engage with the discussion and your understanding of climate physics is unlikely to improve if you are unwilling to learn. Continue with this approach and you will find people will no longer respond to your questions as your responses suggest you are not interested in the answers.
  17. Tom and scaddenp:

    Note how this book indicates that radiation measurements are just one of several factors that must all be considered in order to arrive at meaningful results.

    Understanding Climate Change Feedbacks
    Panel on Climate Change Feedbacks, Climate
    Research Committee, National Research Council

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    Moderator Response: [Dikran Marsupial] center tags fixed
  18. Another question to all:

    The chart in this topic "Energy Content in the Climate System" shows very clearly the dominance of the energy stored in the oceans compared with everything else. (It is nearly 20 times that in the continents, and nearly 30 times that in the atmosphere.) Even in over 40 years (1961-2003) the error bars still overlap so we cannot prove an increase statistically, though it does look likely and of course an increase would correlate with temperatures.

    Now, there is also reference to the 1998 El Niño being the biggest in recorded history. El Niños effectively send heat straight through the atmosphere and out to space. So there was some cooling after it especially in 2002.

    Now, these El Niños will continue happening and we could deduce that the magnitude of the heat which they send to space depends on the the magnitude of the prior build up in the oceans.

    So my question is: Why can't the world just relax, knowing that El Niños will act like a pressure valve and release whatever excess heat any global warming may cause in the future?
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    Moderator Response: [Dikran Marsupial] Because as well as El Ninos, there are La Ninas, which do the oposite. ENSO is an oscillation, so on a multidecadal scale its effects average out to zero and it doesn't have a great effect on multi-decadal trends.
  19. Doug, I'm having trouble understanding (several of) your responses to Tom's explanations.

    Especially those that rely on contrasts between day and night observations. These items are important for gathering information about particular locations. For global climate, however, the obvious issue is that when it's 4am in one place, it's 4pm at the equivalent location on the other side of the globe. Whatever is happening in the way of diurnal cooling/warming at one is reversing at the other - with appropriate adjustments for geographical variations.

    It's not clear to me that your ideas account for this adequately.
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  20. Doug "So my question is: Why can't the world just relax, knowing that El Niños will act like a pressure valve and release whatever excess heat any global warming may cause in the future?"

    You might have noticed that this wonderful El Nino process you're talking about seems quite capable of cooking the whole of Australia - esp when the Indian Ocean gets into the act as well.

    Sounds a lot like telling people not to worry about floods - after all the water eventually ends up in the ocean or the aquifers so 'Don't worry. Be happy.'

    And a minor technical quibble. How is it that this 'release' by the ENSO 'pressure valve' doesn't result in temperatures declining back to earlier levels in the following years?

    If this pressure valve had been doing it's job, surely temperatures would be fluctuating up and down around some level or other rather than steadily increasing decade by decade.
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  21. Doug,

    You have wandered through a trail of 100 posts now, hitting everything you can and being soundly refuted at every turn, and yet you keep finding new reasons to ignore what you are told or educating yourself beyond your ignorance. You continue in pursuit of more and more reasons to declare scientists wrong and ignore the problem.

    If this topic concerns you so much, you need to put more time into studying, and less into posting.

    When you study, you need to open your mind and learn, instead of starting with a desired outcome and trying to interpret everything in terms of that outcome.

    You need to recognize that you have a problem, a very serious bias towards arriving at a predetermined conclusion, and that bias keeps you from adequately learning the science.

    You need to recognize that the science is very, very, very complex. There is a lot to learn, and in a lot of different areas.

    You need to trust other people, and ask questions to learn instead of trying to score points or find weaknesses for the sake of later scoring points [And after 100 posts your score right now is zero, by the way].

    In a nutshell, you need to become a skeptic. A skeptic doesn't believe anything, and refuses to commit until he is sure that he solidly understands and has no doubts.

    You are not a skeptic. You believe a lot of things, like in the magic of ENSO, which is really nothing more than a global game of oceanic peekaboo. You may actually be on to something in thinking of it as the globe's pressure valve, but if so, it is one that is inadequate to counter the forces that are building beneath it. But this is good evidence of your own approach. When you find a concept you like, you accept it with extreme prejudice and without hesitation, even when you do not have enough facts to quantify the effect enough to justify your own position, and in fact when all evidence points away from your desired conclusion.

    You also refuse to believe in a lot of things, like the complex and irrefutable physics behind the greenhouse effect.

    You also, clearly, are not trying to learn everything you can, but rather only those things that you hope will support the result that you'd like to believe is true.

    Please become a skeptic. Please.

    Beyond that, this thread has grown extremely tiresome and has wandered way, way off topic. I'm amazed at the patience that all of the (well educated) SkS regulars have shown you here. A large number of people have gone to great lengths to help you, in a carefully reasoned tone that your own hubris and attitude does not mirror.

    It's time for you to do some serious studying, and to avoid nuthouses like WUWT in the process. Go learn the science. This site is a good place to start, but certainly shouldn't be your only resource. It's actually better as a place to figure out what else you need to learn (in my opinion). But look around, follow tangents, and educate yourself.

    Until then, you are just confused and passing your confusion to others.

    The world needs skeptics with the energy to educate themselves, not ignorant ideologues with the energy to broadcast their hoped for assumptions.
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  22. DougC:

    How about a new version of this? It's been such fun playing question time; it is now time for you to provide some answers that are substantiated and based on researched self-consistent science rather than your opinion.

    Following are questions based on several points in #165. Think of this as your homework assignment; don't come to school without doing it first -- and don't ask someone else to do it for you.


    165 #1: In your model, conduction/diffusion 'prevails'. Yet you state there have been cooling periods; cooling requires a heat deficit. What causes this? Your answer must be detailed and not just 'natural cycles;' that's a cop-out of the uninformed. Hint: much is fully explained on other threads. Find them. Read. Learn.

    165#2: Why does the surface warm during the day? What happened to the ability of your conduction/diffusion mechanism to 'prevail'?

    165#3: Incorrect. Go find out why measuring radiation is not the same as measuring temperature. What have we learned (hint: a great deal) from such radiation curves? Hint: read TomC's excellent comments in this thread - again.

    165#4: Incorrect. Go find out why it is the trend in temperature and heat gain that matters. What is that trend over the last 40 years?

    You state that O2 absorbs UV: Find out how much of the incoming solar energy is UV. Then see if UV even has a place in this discussion.

    What are 'feedback photons'? Please describe the conversion of heat to 'full spectrum IR.' Why does this 'conversion' only occur at the surface? Is there a difference between IR photons leaving the initially warmed surface vs. those leaving the surface after feedback? Please provide some substantiation that 'all can get out' by '4am'. Include in your answer a discussion of the significance of an increase in nighttime temperatures over a multi-year period.

    You conflate seasonal temperature variation with the multi-year warming trend. Why does the fact that it cools in the winter not have any significance in this discussion? If, as you've claimed, 'conduction will prevail,' why do we have seasons at all?


    Until you can answer some questions, in self-consistent detail, your understanding still has gaping holes (and you now know that it does). SkS is not a soapbox; this is a place to test your ideas and accept that others know this science better than you.

    Sphaerica gives excellent advice. I can add only this: Think about what you read. And more importantly, think about what you are going to say before you write it. Always ask yourself, 'is what I have to say really that new and important or might someone already have this figured out?' Try to avoid adding to the noise; add instead to the useful dialog.
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  23. Adelady @169, DougCotton appears to believe the that all the heat in the surface layers of the ocean can be dissipated in a matter of seconds, or minutes, so that the only think that preserves the warmth through the night is the feedback loop of back radiation re warming the surface after some heat is initially dissipated. In other words, he has no concept of thermal inertia.

    It is easily determined that it would take approximately 28 days without sunshine for the surface 100 meters to lose 1 degree C with a net upward flux of 160 Watts/m^2. The 160 W/m^2 is just the average net upward flux from the surface excluding solar radiation, while the 100 meters is an underestimate of the typical depth of the mixed layer, in which turbulence caused by winds keeps temperatures near constant with depth. That being the case, the temperature drop at night in the ocean is negligible, except at the very surface where the heat escapes to the atmosphere quicker than it can be replenished from below.

    As always, Science of Doom has an excellent post (in fact four) on the subject, and even developed a model of the diurnal temperature range in the ocean:



    And for some empirical results:



    As you can see, even under calm conditions the top most layer only varies in temperature by about 3 degrees at most, for a 40 W/m^2 variation in the surface IR radiation at most. In other words, the up welling IR radiation from the surface is near constant over water, and the dissipating feedback loop imagined by DougCotton is simply unphysical.

    Over land, there is substantially greater variation in temperature, but temperatures are normally kept within a narrow range for all that. Because of this, the up welling IR radiation, which is in fact black body radiation from the surface also persists through the night with only minor variation. This can be seen in actual measurements of the surface radiation, in this case over a banana plantation in Brazil:



    The thing to note is the Net Radiation (Rn), ie, down welling solar radiation minus the up welling IR radiation. At night that becomes just - the up welling IR radiation, and as can be easily seen, it is near constant through the night.

    Once again how Doug imagines things to be has no support either in theory or observation.
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  24. DC - Ramanathan & Coatley lay the foundations, and you need to understand these first. Since you have now switched to discussion of feedbacks associated with clouds etc., can we now assume that you accept that the greenhouse effect is real and that these climate scientists do actually understand radiative physics? Changing your website to reflect this would be nice. Discussion of feedbacks (ultimately a discussion about climate sensitivity) is a different proposition and should do that on an appropriate thread.
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  25. Thanks Tom. I started by including some remarks about oceans, but I cut them out to keep my contribution short. (And I've not looked at Doug's site so I had to go on what I've seen here only. I'm not wonderfully well right now and I'm grumpy enough without deliberately seeking things out to worsen my temper.)

    And Doug. If you were not thrilled with RC 1978, you might do better with an overview like Spencer Weart's. Look through the Contents-Site Map here and you can choose topics that interest you. Follow the references as you come across them.

    And I heartily endorse the previous referrals to Science of Doom. Lots of good science, presented in digestible amounts. It's not as simple as reading a novel, but it's an excellent self-education resource.
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  26. In response to all: Please respect the fact that I am behind with business matters and, whilst I believe I can respond satisfactorarily to all points raised, posts on here are not the place because it will require much more detail. I will be adding a page about all this (you know where) in about two weeks time.

    In the meantime I shall address the key issue in the final paragraph of #165, because, unless anyone can show sound reasons (based on physics) that what I say there is incorrect, then my case stands. Here then is a more detailed explanation which needs to answer the question ...

    What happens to back radiation (which I have also called feedback) in particular that from CO2 when it strikes the solid surface?

    It creates heat which flows into the surface during the "warm-up" phase in the morning and maybe early afternoon. As the night approaches that heat can flow out at a similar rate to which it flowed in. Allowing for cloud cover, there are less than 12 hours of direct sunlight on average, so it has a reasonable, though not certain, probability of cooling off by about 4am (say) half way between summer and winter. In summer it may not cool off entirely, so heat builds up in that hemisphere, particularly in the oceans which hold about 90% of all heat (continents ~6%, atmosphere ~4%.) We know the local surf is warmer in summer. So, what comes in as CO2 frequency photons then becomes heat. Then that heat (along with the heat that came from direct sunlight) is radiated as the surface cools and that radiation contains many other IR frequencies (ie it is "full IR spectrum" near enough.)

    From the area of the notch in the chart Tom provided, we can see that only a small percentage is captured by CO2. And so, when the process repeats over and over, it rapidly approaches a limit where virtually all go to space. It makes little difference what size that notch is because it is still a small portion of the total area under the curve.
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  27. Tom #173: Regarding your point on thermal inertia, let me start with an analogy which I will come back to at the end:

    Imagine a small glass of water in an air conditioned room. The water represents the oceans and the room represents the whole of the Earth beneath the surface. Leave the glass for a few hours and the water ends up at the same temperature as the room. Drop a hot coin in the glass (representing the warming by the sun that day) and it also cools down to a "base" temperature supported by the heat in the room. To warm everything you have to alter the air conditioner setting.

    Now, as we have seen in this Trenberth article, the heat above the crust is contained in (roughly) 90% ocean, 6% land, 4% atmosphere. Compared with all of this, the heat in the rest of the Earth below the surface (and below the floor of the oceans) is many orders of magnitude greater.

    What the atmosphere and oceans "see" is what I call the "break out" temperature at the surface (or floor of ocean) of the temperature gradient of the heat flow from the core. For example, German borehole data showed 270 deg.C at 9,000 metres with a linear trend down to about 12 deg.C at the surface. (I suggest it would be about 25 deg.C at the equator and well below freezing point at the poles. It is roughly the 4am temperature on a calm night.)

    I suggest that this "break out" temperature can vary naturally for whatever reasons. It certainly must have done so during ice ages for example. It is the "temperature in the room" in my example, and the natural causes affecting it are the air conditioner. The oceans, the land and the atmosphere are all controlled by it, just as is the temperature of the water in the glass and that of the coin.
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  28. #177 "It certainly must have done so during ice ages for example."

    Doug! Check the definition of 'ice age'.

    I'll leave others to deal with the rest of this one.
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  29. adelady#178: "Check the definition"

    Mr. Cotton doesn't need definitions; he prefers making stuff up (break out temperature?)

    For the rest, we could start with the fact that geothermal forcing is much much less than radiative forcing (its on a prior thread). So his 'small glass in a room/drop in a hot coin' analogy is yet another case of not enough fact, too much hot air.

    "Vary naturally for whatever reasons"? And this is what we are supposed to believe is physics?
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  30. Just one more thing for you to think about for the next two weeks before I return...

    Note the conclusion of the quote in #167 about there being inadequate records of all the mentioned factors for climate models.

    This means that it is impossible to determine whether or not all radiation is escaping to space from empirical measurements of radiative flux, due to the inadequate information we currently have on other factors that could causes differences between incoming and outgoing radiation.

    I have put forward a sound physical argument (#176) as to why I believe all radiation is escaping.

    Remember that, according to 2008 NASA diagrams, 5% of total incident insolation is conducted to the atmosphere (not radiated) and then drifts upwards by convection. This may take months to get to the top of the troposphere, for example. The rate at which it does determines the temperature gradient of the atmosphere, not any supposed warming due to CO2 captures. You cannot produce any evidence that all radiation is not escaping, including that originating from the extra energy in any molecules which may have been warmed by CO2 captures.

    Carbon dioxide is but a small leaking dam at the foot of a mountain which can never cause the gradient of the creeks coming down to alter, and never cause a flood at the top.
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    Response:

    [DB] "I have put forward a sound physical argument (#176) as to why I believe all radiation is escaping."

    Umm, nope, not so much.  You have spent many an electron detailing fanciful conjecture with no supportive physics.  In short, you are spinning yarns.  Fiction.  As in "making things up".

    This is a science forum wherein interested individuals discuss the science of climate and climate change.  Please spend some time trying to learn enough of it to carry on some 2-way dialogue with other parties here.

    Muoncounter asked you some excellent questions in number 172 above.  I will hold you to answering them before this can go on to other things.  As it stands right now, you are wasting others time due to a lack of interest in actually learning.

  31. DougCotton @176, data is not a Rorchach Test for you to read in whatever your preferred theory. It carries distinctive information which tends to confirm some theories, and invalidates others. In this case, the observed OLR clearly invalidates any theory that does not acknowledge that CO2 in the atmosphere has a warming effect on the surface. In fact, the observed data is logically inconsistent with any theory that does not include a warming effect from CO2.

    In order to continue your rorschach approach to science, you focus on the size of the reduction in Outgoing Long wave Radiation as proof that the down welling long wave radiation must be small. It never occurs to you to look at the down welling long wave radiation itself, or to accept its measured values, and the global estimates derived from those measurements.

    Well, here is some actual data. Anybody committed to following the data rather than imposing their view regardless of the data will clearly see the down welling long wave radiation is very significant:







    As can be seen, the down welling long wave radiation is large, particularly in the tropics. In Darwin in winter (June), it still has a mean value of 372 W/m^2. In summer (January) that rises to 430 W/m^2.

    You want to ignore that fact because of the size of the CO2 notch. As can be seen from the following simultaneous spectrums over Barrow Island (in the Arctic) the size of the CO2 notch is not a reliable guide to the amount of back radiation, and certainly does not determine the quantity of that radiation. That you should think so suggests you are again employing your absurd single layer atmosphere model.



    And just to prevent a confusion before it starts, the back radiation has not effect on the long term energy balance, which is governed by the net Top of Atmosphere energy balance. If Back Radiation is high, that just results in more convection carrying heat away from the surface - if it is low, that is compensated for by less convection. In the end the TOA balance governs all.
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  32. This thread may have been annoying and irritating. But.

    I will treasure forever "data is not a Rorschach test".
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  33. "Remember that, according to 2008 NASA diagrams, 5% of total incident insolation is conducted to the atmosphere (not radiated) and then drifts upwards by convection. This may take months to get to the top of the troposphere, for example."


    In fact it takes mere days for heat to get to the top of the atmosphere in its optically thick wavelengths by radiation, and mere hours by convection. Again Doug just makes things up with no attempt to check his assumptions against reliable sources.

    I do not find this game of wack-a-mole amusing. I participate in these threads to counter disinformation for the benefit of interested readers who have not made up their minds to believe anti-science rather than reality. If a denier comes along who just throws out falsehoods as fast as he can imagine them, I cannot keep up, and nor should I have to.

    We are frequently reminded that posting on Skeptical Science is a privilege, not a right. DougCotton is clearly intent on abusing that privilege. Can I suggest that in future his posts be simply deleted unless he backs every disputed or dubious claim with a reference to either a text book or the peer reviewed literature.

    For me it is a matter of both good manners and ethical necessity to take reasonable efforts to ensure that the information you provide is accurate (and to correct it when you discover it is not). I think that is a reasonable standard to expect of any poster on this site.

    I would go further. Anybody who does not accept the obligation to self fact-check shows by their actions that the truth of what they say is of no consequence to them. They value that truth at the same level as the effort they are prepared to expend to ensure that what they say is true, which in DougCotton's case is clearly no effort at all. At that point the question as to whether they are actively dishonest (ie, the knowingly tell untruths) or simply negligently dishonest (ie, they tell untruths because the cannot be bothered to make the effort of telling truths) is purely academic. They are enemies of truth regardless and have no place in public discourse.

    ( -Snip- )
    0 0
    Response:

    [DB] A-step-too-far snipped.

  34. Tom: Re #181 Just briefly, then I must get on with business matters for 2 weeks: please read my #180 then note ..
    ( -Snip- )
    0 0
    Response:

    [DB] Please note that posting comments here at SkS is a privilege, not a right.  This privilege can and will be rescinded if the posting individual continues to treat adherence to the Comments Policy as optional, rather than the mandatory condition of participating in this online forum.

    Moderating this site is a tiresome chore, particularly when commentators repeatedly submit offensive, off-topic posts or intentionally misleading comments and graphics or simply make things up. We really appreciate people's cooperation in abiding by the Comments Policy, which is largely responsible for the quality of this site.
     
    Finally, please understand that moderation policies are not open for discussion.  If you find yourself incapable of abiding by these common set of rules that everyone else observes, then a change of venues is in the offing.

    Please take the time to review the policy and ensure future comments are in full compliance with it.  Thanks for your understanding and compliance in this matter, as no further warnings shall be given.

  35. Sigh - so know we have argument from Personal Incredibility? You have been pointed to papers, articles, had question patiently explained but no, it appears you prefer ignorance to actually finding the answer. You can "suggest" whatever, but I will stick to strong mathematical theory, rigorously tested against empirical data thanks.
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  36. ( -Snip- )
    0 0
    Response:

    [DB] Please note my replies to you upthread in 180 and 184.  Tom has already expressed his frustration in dealing with your disingenuousness.

    Either follow the direction given or give it a rest.

  37. #179 Muon:

    (a) There is as yet no scientifically proven theory (out of at least half a dozen suggested by various scientists and academics) which explains the natural variations in climate which are part of the historic record. Hence I carefully chose the words "for whatever reason."

    (b) It is irrelevant what you or anyone calls what I call the "break out" temperature. It is derived by extrapolating the linear trend of the downward temperature gradient from the core to the surface, and so it is the intercept of that trend line at the surface.

    (c) Physics tells us that the rate of terrestrial heat flow is not what is important - yes it is slow, simply because the rate of conduction of rock and clay etc is slow. So too is the rate of conduction of the heat through the glass in the room. It doesn't matter. There has been plenty of time in the life of the Earth.

    (d) If you or anyone is trying to tell me that the heat in the oceans is going to affect the heat under the whole of the Earth's surface including the core, rather than vice versa (as Physics dictates) then you are not correct.
    0 0
    Response:

    [DB] Mr. Cotton, I simply cannot tell if you are being intentionally obtuse and evasive or merely relying upon natural ability and giftedness.

    In any event, you are completely and utterly wrong here.  I suggest starting at square one and grabbing a physics textbook for starters.  You are many years of study from being able to get a good handle on climate science.

  38. DC#187: "I carefully chose the words "for whatever reason.""

    Yes, and empty words they are.

    "Physics tells us "

    You are using no physics. You are making things up on the fly to suit your preconceived notions. Your analogies are bogus. In other lines of work, that would be called 'fraud' (but not here, because of the Comments Policy).
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  39. One more try. Doug, we've referred to Science of Doom a few times.

    This page is helpfully titled "Confusion over the basics". It refers to just one of the sections on back-radiation and several other nice expositions on various topics.

    I've been through most of these myself. You may be like me and sign up for the "skip the equations" club. It makes my life easier - but - it does mean that I'm obliged to take experts at their word on the content and meaning of those equations. (and sometimes just sit back and watch admiringly when they argue about arcane minutiae I've decided not to expend effort on myself.)

    Either way, you're in for a fair amount of reading. And if you really want to be fully involved in technical discussions, you're in for a lot of detailed note taking and serious brain work.
    0 0
  40. ( -Snip- )
    0 0
    Response:

    [DB] Mr. Cotton, as you have previously stated that you wouldn't be back and then rescinded that offer, and have continued (despite able advice to the contrary) to avoid supporting your position with actual physics-based mechanisms with roots in the literature, and since you have expressed being away for 2 weeks on business anyway, it is time for a break.

    I'll leave this up for a bit, then your SkS account posting privileges will be suspended until September.  You may then resume participating here, but you will still be held to the mandate of basing your comments on scientifically supported basis' and also to "not make stuff up".

  41. Doug#190:

    No one said anything of the kind; please try to read carefully. You, on the other hand, have denied the role of solar radiation in the energy balance of the earth. Good luck selling that!

    Now say goodbye for real.
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  42. Doug, as others have said, you're clearly making up an alternative universe here, and ignoring the physics and mathematics, and most crucially the evidence along the way. You should be aware that a major in physics and maths does not automatically confer an understanding about earth science or climate science, just as the reverse is true. You have been directed to a number of excellent initial sources of information by the patient commenters above. Have a read of them, and you can begin your journey into the world of real climate science.

    I admire the patience of people here dealing with you, but I am also disappointed that you have been allowed to totally derail a thread in which Kevin Trenberth at #68 took the time to answer queries regarding his opening article. It's kudos to SkSci that he did this as you don't often get a chance to exchange views with the most active climate scientists in the world, but a shame the discussion could not have continued from there. Up until that point I was learning quite a lot. I presume he's no longer reading this thread, but I appreciated both the article and his reply to some of the first 67 posts.

    Perhaps this is another example where a RC-like 'bore hole' or 'climastrology' thread into which to drop these kinds of persistently made up and irrelevant posts by DougCotton would be a good addition to Skeptical Science? The fish can be shot in the barrel in a place where they do not detract from interesting topics!
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  43. Trenberth's curved trend line for sea surface temperatures can now be extended with NASA data available to the end of August 2011. The trend passed a maximum a few years ago and has been declining since. That is why NASA data currently shows virtually all of 2011 below 2003 - the year 2003 was on the way up and 2011 on the way down. This is just one piece of empirical data which is in accordance with my group's theory that it is crust temperatures (themselves controlled by core temperatures) which are forcing climate, not solar insolation.

    Over the last two weeks I have been doing calculations on borehole data and this very convincingly supports the theory. We see different underground temperatures which are related to latitude, thus confirming that frictional heat (due to the moon) is being generated in the core, more at the equator than at the poles.

    There is further empirical support in the fact that, on the days when the sun is directly overhead in the tropics, whether 23 deg latitude or at the equator, the temperature varies with latitude. This would not be the case if solar insolation were the only factor. The variations with latitude correlate with the underground temperatures. Associated variations in the angle of the sun at different latitudes are not sufficient in themselves to explain the empirical data.

    In effect, the empirical data debunks the concept that climate is forced by factors involving solar insolation and atmospheric gases.

    Yes, indeed, it is the sun's heat which causes what is only temporary warming each day. Solar heat flows into the surface and back out again. The net flow is small, but the absolute flow each way is quite significant as you should know if you've ever burnt your feet on hot sand. Because that flow in and out is far greater than the net flow, equilibrium can be and is achieved between the surface and the first 1mm or so of the atmosphere. From there up, convection takes over. So, whilst core heat has helped build up the temperature of the atmosphere over billions of years, it now plays a supporting role, making it easier for the sun to warm the air when the surface is warmer, and harder when it is cooler. Some heat is retained in the surface, and especially the oceans, from local summer to winter.

    Our group's theory explains all the physical observations, including the extending of the day's warmth into the early evening and the warmer ocean in local summer.

    It takes only a very small percentage change in the temperature of the liquid core (~5700 deg.K) to give rise to the kind of variation we have seen since the Little Ice Age. And that is perfectly possible (and probable) due to the variation in total gravitational force from the moon plus the major nearby planets.

    Our theory is supported by the physically observed facts. The "consensus" theory is not supported by Trenberth's trend, nor by the magnitude of the variation in temperatures with latitude, nor by the very significant correlation between the extrapolation of underground temperatures (using only data from 200 metres or deeper - beyond the influence of solar insolation) to the surface and the local above surface stable base temperatures.
    0 0
    Response:

    [DB] I'm not going to even begin to address all the nonsense presented here, but just some of the egregious:

    1. Provide a link to the specific NASA data which you claim supports your Sea Surface Temperature (SST) claim
    2. Provide a link to a reputable source showing that your use of the word "theory" instead of "hypothesis" can be supported
    3. As for latitudinal variations in the angles of the suns rays being insufficient to explains measured temps: get a grip.  The Earth has a large, moving body of water with a gaseous envelope surrounding that called the atmosphere.  They do stuff like rearrange heat within the system.  Get used to it.  Or prove that they don't.  The empirical data strongly supports the radiative properties of the atmosphere powered by the sun as being the thermostat regulating global temps.  It's just physics.
    4. Global borehole data, like SST data, does not support you:


    Global surface temperature change over the last five centuries from boreholes (thick red line). Shading represents uncertainty. Blue line is a five year running average of HadCRUT global surface air temperature (Huang 2000).

    Mr. Cotton, playing make-believe is all well and good when writing stories.  But for things in climate science the accepted practice is to use physics.  And here at Skeptical Science participants use the language of science and physics to explain climate science. 

    And it is those selfsame physics, based on more than 150 years of study and research (upon which our civilization is built) that says that your pet hypothesis (which is all that it is, not a theory) which you ignore.

    So by all means, play a 21st Century Don Quixote and tilt at windmills.  But unless you can express your points in cogent scientific fashion, which involves using physics to explain why those processes and metrics we can empirically see and measure work so well for everything our civilization depends upon, but do not apply to controlling global temps.  And the onus is on you to do it in step-by-step fashion on appropriate threads, or those comments deemed off-topic will be deleted.

    Until then the participants here will rightfully ignore you.

  44. DougCotton @193, the frictional heat generated by lunar tides has been well quantified. The energy dissipated by the M2 tide is approximately 2.4 Terrawatts. Assuming energy dissipation scales with the magnitude of the tide, that means the total energy dissipated by all tides is around 6 to 6.5 Terrawatts at most. In other words, the energy dissipated by tides averaged over the Earth's surface is at most 0.013 W/m^2.

    From there, a quick calculation with the Stefan-Boltzmann Law shows that at most, tidal energy could raise the Earth's temperature by only 22 degrees K above absolute zero, or raise the temperature by 0.0025 degrees K above the current Mean Global Surface Temperature of 288 degrees K.

    Of course, anyone who gave this casual thought already knew that the combined energy from tides and radioactive decay cannot significantly contribute to the Earth's surface temperature. If they did, it would be impossible for -89.2 degrees C (as it has in an Antarctic winter). Indeed, as the heat from the core is conducted equally in all directions, the necessary consequence of its being the major source of surface warmth would be that the surface would be nearly equally warm at all locations - ie, the tropics and poles would have similarly balmy (or frigid) conditions.

    But by all means, go ahead and believe the 0.013 W/m^2 of tidal energy is far more important than the (average) 240 W/m^2 of solar energy. Please do not let any fact checking disturb you from the fantasy land you are so keen on inhabiting.
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  45. Fourier already knew of the internal heat of the earth and noticed it was negligible. Two centuries ago.
    0 0
  46. To both:

    I assumed you knew where to find NASA data at http://discover.itsc.uah.edu/amsutemps/ where you can select "Sea Surface," then tick 2003 and 2011 and 'redraw."

    The above borehole plot over hundreds of years is irrelevant because it was probably at shallow depths where solar insolation had an effect. Note the yellow linear trend line on this, the deepest (9,000 metre) borehole, and note the intercept at the surface around 10 to 12 deg.C.



    Now you can see similar plots for hundreds of other boreholes using the link in (d) at (-link snipped due to antivirus security threats-)

    Suppose (-Off topic Gish Gallop snipped-)
    0 0
    Response:

    [DB] Last warning about being off-topic.

    BTW:  Borehole data is at depth to avoid surface temp contamination of the data.  Which you would know if you had bothered to actually look at data that might confound your perambulations and not just cherry-pick the little data which may through happenstance support you.

  47. Again, a Climastrology button is needed for Mr. Cotton.
    0 0
  48. DougC#193: "There is further empirical support ... empirical data debunks the concept that climate is forced by factors involving solar insolation"

    Your conclusions based on this very limited empirical exercise were shown to be completely incorrect the last time around on this very thread. On further inspection of #193, your earth-heat-lunar-tides idea is utterly unsubstantiated as well (and in my opinion, patently absurd).

    The challenge made there still stands: show data and research from credible sources - peer reviewed whenever possible - that support your 'diffusion will prevail' model. Until you can meet that challenge, your ideas remain merely your personal opinion. Until you can meet that challenge, all of your pronouncements must be read with the preface, 'in my opinion.'
    0 0
  49. Cotton: "In effect, the empirical data debunks the concept that climate is forced by factors involving solar insolation and atmospheric gases."

    Long-term orbital cycles, then, should have very little effect on temps, and certainly not the effects shown in the established long-term temperature record. Low-latitude glacial deposits should be impossible, despite the historical evidence. And stratospheric cooling with tropospheric heating -- well, it must just be a long-term cycle with some other explanation.

    Locked in, this one.
    0 0
  50. Wow. As I read #193 I found myself wondering what part Pyramid Power and Hagbard Celine had to play in this hypothesis.

    Doug, you are attempting to overturn 100+ years of science without showing a single equation or data point. That might get you a special on the (now ruined) History Channel following Ancient Aliens but the scientific community is not going to take you seriously.
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