Guest post by Bob Irvine
ABSTRACT
The Earth’s feedback response to warming is independent of the nature of the forcing that caused that warming. The question I intend to examine is whether the nature of the forcing will have a significant impact on the initial warming or the response time of the earth’s system. I looked at changes in three different types of forcing and their effect on the earth’s temperature response.
1. Changes in solar forcing caused by variation in solar output at the sun’s surface that may cause changes in Cosmic Ray flux or other solar multiplier effects.
2. Changes in solar forcing caused by changes in the earth’s milankovitch cycles (Last Glacial Maxima, LGM) and volcanic activity that do not affect cosmic ray flux.
3. Changes in Anthropogenic Green House Gas (AGHG) concentrations.
The IPCC and others assume that climate sensitivity derived from #2 (Last Glacial Maxima, or Milankovitch cycles and volcanic activity) also applies to #1 and #3. This paper attempts to show that this is unlikely to be the case when the best available data is compared.
For #1 we found the climate sensitivity to be between 1.0°C and 1.8°C per Watt per Square meter of forcing. For #2 we found climate sensitivity to be approximately between 0.4°C and 1.2°C per W/M2 and for #3 we found climate sensitivity to be between 0.1°C and 0.36°C per W/M2.
INTRODUCTION
Climate sensitivity is the temperature increase at equilibrium for each Watt per square meter of forcing or “X” in the following equation. X°C/WM-2 .
Generally as the planet warms it activates various feedbacks. A negative feedback will decrease the earth’s system response time at the top of the atmosphere and a positive feedback will increase this response time. For example, a decrease in sea ice will slow the return of energy to space and can, therefore, be considered a positive feedback to warming.
Not all feedback’s, however, are a response to warming. For example, if the cosmic ray effect is real then it can be considered a positive feedback to increased solar activity that is not related to warming. Similarly different types of forcing can have different response times at the top of the atmosphere. I intend to show in this paper that changes in long wave GHG forcing have a considerably shorter response time than changes in short wave solar forcing and, therefore, can be expected to have a lower climate sensitivity.
I, therefore, intend to show that the IPCC’s climate sensitivity based on #2 above should not be applied to AGHGs.
I have used the IPCC’s climate sensitivity derived from #2 above to calculate the current equilibrium temperature due to AGHG’s already in the system and compared this with the NOAA actual temperature since 1880 in Fig. 1. The calculations done to produce the graph below are set out in Appendix “1”.
Basically the IPCC’s agreed CO2 concentrations were used to calculate expected equilibrium temperature which was adjusted using the IPCC’s 3rd and 4th assessment reports figures to include all AGHG’s (i.e. NO2, CH4, Halogens etc.). All calculations used to produce this graph (fig. 1) are generally agreed and accepted and used by the IPCC.
The inconsistency of the IPCC central prediction and upper limit with the actual data (blue line) is immediately apparent. It is possible that the lower IPCC limit might be compatible but even this becomes untenable when climate sensitivity to changes in Total Solar Irradiance (TSI) which include any solar multiplier effects, #1, is taken into account. This sensitivity, #1, will be estimated in section “A” below. Section “B” will show how the IPCC derived their climate sensitivity for #2 above.
The IPCC’s position is that industrial aerosols have artificially cooled the planet masking the warming effects of the AGHGs and that equilibrium temperature is approximately 1.5 times transient or current temperature. Section “C” will show that even these are not enough to avoid the conclusion that climate sensitivity due to changes in AGHGs, #3, is considerably smaller than both #1 and #2.
Fig. 1 AGHG Forced equilibrium temperature using the IPCC’s sensitivity based on #2 (LGM and volcanic) and compared to actual temperature as measured by the NOAA since 1880. The upper IPCC limit assumes a climate sensitivity of “X” = 1.2, the IPCC central prediction assumes “X” = 0.8, and the lower IPCC limit assumes “X” = 0.4.
#1. SECTION A We used two methods to match TSI (Total Solar Irradiance) changes as Watts/Square meter at the earth’s surface with the best temperature data available. These TSI changes will affect the cosmic ray flux and possibly have other solar multiplier effects as they are caused by changes in solar activity at the sun’s surface.
If these changes in TSI lead to greater temperature changes per unit forcing than solar changes that do not result in changes in the cosmic ray flux, such as Milankovitch cycles or volcanic activity, then this would lend some credence to theories suggesting that cosmic rays have a significant effect on the earth’s surface temperature.
The two methods we will use are a) compare solar irradiance changes over the last millennium with temperature records, and b) compare temperature and forcing for the 11 year sun cycle.
a) The TSI variations are taken from Swingedouw et al (2011) who used the Bard et al (2000) reconstruction and are the same as those used by Crowley (2000). The scaling used is from Lean et al (1995). Lean et al (2002) and Foukal et al (2004) suggest that long term irradiance changes could be considerably less which would imply a higher temperature sensitivity to a given forcing.
Fig. 2, W/M2 at the earth’s surface due to changes in Solar activity for the last millennium.
Fig. 3, Solar activity for the last 1100 years.
I have used the temperature reconstructions of Mann 2008 EIV, Moberg 2005, Loehle 2008 and Ljungqvist 2010 to represent temperature change over the last millennium. They are, I believe, the best available series at the time of writing. These temperature reconstructions are reproduced in Appendix “2”. An approximation of the range of temperature over this period is then compared with the range in solar forcing at the earth’s surface.
With considerable uncertainties, this comparison will give us an approximation of the climate’s sensitivity to changes in solar forcing at the earth’s surface that include any cosmic ray effect and/or other solar multiplier effects .
Fig. 4, Maximum and minimum temperatures for 4 different temperature reconstructions over the last 1500 years. The warmest three decades and the coolest three decades from each reconstruction are shown.
From fig 2 and fig 3 the range in solar forcing at the earth’s surface over the last 1000 years excluding the 20th century is approximately 0.6 w/m2.
From fig 4 the range in temperature in each of the four reconstructions can be seen. It is then possible to calculate “X” where X is the change in the earth’s surface temperature in degrees Celsius that results from a one w/m2 change in forcing.
From Fig 4 the range in temperature for Mann 2008 EIV is approximately 0.75°C, for Moberg 2005 is approximately 0.9°C, for Loehle 2008 is approximately 1.1°C and for Ljungqvist 2010 is approximately 0.9°C.
Climate sensitivity is described by the equation X°Celcius / wm-2. .
The value of “X” will change, with time from equilibrium, and with any other changes in the earth’s feedback systems etc. For the purposes of this paper, however, “X” will be considered to be linear for a given forcing. This paper is considering the possibility that “X” will change considerably depending on the nature of the forcing that drives any change.
The value of “X” is then derived for each of the four different temperature reconstructions.
For Mann 2008 “X” equals 1.25 (0.75/0.6)
For Moberg 2005 “X” equals 1.5 (0.9/0.6)
For Loehle 2008 “X” equals 1.8 (1.1/0.6)
For Ljungqvist 2010 “X” equals 1.5 (0.9/0.6)
These values of “X” should approximate the equilibrium response since the data is taken over a millennium or more. There are considerable uncertainties in these estimates of climate sensitivity that derive from the max/min method used and the error margins of the various temperature reconstructions used.
It is worth noting that if the max/min method used overstates the temperature response then it is also likely that max/min method also overstates the solar forcing at the earth’s surface causing some of the possible error to be cancelled.
It is beyond the scope of this paper to estimate these uncertainties other than to say that the climate sensitivity, as calculated from current knowledge by this method, probably lies in the range 1.25°C/wm-2 and 1.8°C/wm-2.
b) The 11 year solar cycle will also include changes in cosmic ray flux as it too results from changes in solar output at the sun’s surface.
Camp and Tung (2008) use the 11 year sun cycle to derive transient sensitivity of between 0.69 and 0.97°C/wm-2. They also estimate equilibrium temperature as being 1.5 times higher than this which is consistent with the IPCC’s position in their 4AR.
This gives an “X” value for climate sensitivity calculated by this method of between 1.04°C/wm-2 and 1.46°C/wm-2
Combining a) and b) we get the likelihood that climate sensitivity for TSI changes that include changes in cosmic ray flux and/or any other solar multiplier effect will probably lie between 1.0°C/wm-2 and 1.8°C/wm-2.
#2. SECTION B The second type of forcing is one that causes changes in solar energy reaching the earth without effecting cosmic ray flux. These include the Milankovitch cycles and volcanic activity that occur at the earth’s surface and, therefore, are not due to changes in TSI at the sun’s surface.
Annan and Hargreaves (2006) looks at climate sensitivity derived from observation of volcanic activity and the Last Glacial Maxima (LGM).
They studied the literature and concluded that volcanic activity indicates that climate sensitivity would be between 1.5°C and 6°C for a forcing of 3.7w/m2 at equilibrium with the upper limit constrained to 4.5°C after the 20th century temperature record and evidence from the Maunder minimum are considered.
Volcanic activity, therefore, gives a climate sensitivity of between 0.4(1.5/3.7)°C/wm-2 and 1.2(4.5/3.7)°C/wm-2 to 95% confidence.
A & H (2006), after studying the literature, concluded that LGM measurements support a climate sensitivity between 1.3°C and 4.5°C for a 3.7w/m2 forcing to 95% confidence. The upper limit was constrained for the reasons outlined above.
This gives a value for “X” between 0.4 and 1.2 derived from evidence taken from both volcanic activity and the LGM. This agrees closely with the IPCC’s position outlined in all of their assessment reports.
Fig. 5, IPCCs Forcing’s bar graph from their 2007 4AR. Note the large aerosol cooling effect they expect for 2005. Minimum -0.4w/m2, Likely -1.2w/m2, Maximum -2.4w/m2. Note also the large AGHG Forcing of approximately 2.7 w/m2 which at their central sensitivity of “X” = 0.8 should give an equilibrium temperature increase in 2005 of 2.16°C. This is not consistent with actual temperature rise as seen in Fig. 1.
That Milankovich Cycles are overwhelmingly the main drivers of the ice ages, and more particularly the LGM used by A & H (2006) to estimate their climate sensitivity, is shown convincingly by Roe (2006) “In Defence of Milankovich”.
#3. SECTION C Since 1880 an extremely active sun has added directly, approximately 0.5w/m2 at the earth’s surface (Fig. 2). According to our best historical temperature series as seen in section A and after an adjustment to give transient temperature, this active sun should have increased the earth’s temperature by a minimum of approximately 0.33°C to a maximum of 0.6°C since 1880.
According to the NOAA in Fig. 1 the earth’s temperature has risen by about 0.7°C since 1880.
This leaves between 0.1 and 0.37°C plus any industrial aerosol cooling effect to be explained by increasing AGHGs.
This can be summarised by the following equation;
Equation 1; “Y” plus (0.1 to 0.37) = “Z” Where “Y” is the net aerosol cooling in 2010 and “Z” is the total transient warming due to AGHGs in 2010.
At this point we introduce another check on aerosols to get a second simultaneous equation. According to Stern (2006) industrial aerosol production has fallen by over 30% since 1990, Fig. 6. Mishchenko confirms this with satellite measurements showing a drop in sun blocking aerosols since 1990, Fig. 7. Basically, If an increase in industrial aerosols gives a significant cooling as postulated by the IPCC then a drop in aerosols, as has happened since 1990, should cause a significant warming. Here is a supporting quote from the IPCC’s 4AR. “Global sulphur emissions (and thus sulphate aerosol forcing) appear to have decreased after 1980 (Stern 2005)…”
This drop in industrial aerosols can be explained by cleaner combustion techniques forced on people by acid rain and other undesirable environmental effects.
There are other contributors to the earth’s temperature other than Industrial aerosols, AGHGs, and solar, but they are negligible in the context of this paper.
To form a second simultaneous equation we need an estimate of AGHG forcing and an estimate of temperature change since 1990.
Fig. 6 Estimated global SO2 production. Stern 2006
Fig. 7.
The temperature series, Fig. 8, below gives a temperature rise between 1990 and 2010 of approximately 0.2°C. It is uncertain whether natural forcing’s would have increased or decreased this figure so we have approximated this figure to a rise of between 0.1°C and 0.3°C which is an estimate of the anthropogenic temperature change since 1990. The effect of the Mt. Pinatubo eruption in 1991 has also been removed.
Fig. 8 Earth’s temperature 1990 to 2010 according four main temperature series.
AGHGs added 0.82 w/m2 from 1990 to 2010, based on their increase in concentration, which is 28% of the total forcing, attributed to AGHGs in 2010 by the IPCC.
We can now create a second simultaneous equation;
Equation 2; 0.3 x “Y” Plus 0.28 X “Z” = 0.1 to 0.3
Solving for the simultaneous equations 1 and 2 gives total aerosol cooling of between 0.12°C and 0.34°C in 2010 (“Y”). This implies total AGHG forced transient warming in 2010 (“Z”) of between 0.22°C and 0.69°C.
If we assume equilibrium temperature is approximately 1.5 times transient temperature and use the IPCC’s total forcing of 2.9 w/m2 we arrive at an AGHG climate sensitivity of;
“X” = 0.11°C/wm-2 to “X” = 0.36°C/wm-2.
CONCLUSION
To my mind the IPCC’s upper limit and central prediction are not consistent with the NOAA actual temperatures in Fig. 1. If our best temperature series over the last 1000 years are to be believed then the IPCC lower limit in Fig. 1 can also not be reconciled with the actual measured temperatures as has been demonstrated in section A, B and C above.
The IPCC would put 4 possible arguments to explain the discrepancies apparent in Fig. 1.
1. That equilibrium temperature is considerably more than 1.5 times transient temperature which would overturn nearly all the literature on the subject and be inconsistent with all the IPCC’s model assumptions.
2. That industrial aerosols have a massive cooling affect which would be inconsistent with evidence since 1990 (see section C above). They would also need to explain the fact that industrial aerosols generally remain local and are overwhelmingly produced in the northern hemisphere. The northern hemisphere has experienced more warming over the last century than the southern hemisphere.
3. That AGHG sensitivity is not linear. It is initially lower and increases to their published sensitivity at doubling. It is therefore unlikely but possible that the IPCC’s lower limit of “X” = 0.4 could be consistent with the upper limit for AGHGs of “X” = 0.36. This would imply a much larger cosmic ray or other solar multiplier effect (minimum “X” = 1.0, see section A above) than is generally accepted.
4. That temperature measurements over the last millennium are so uncertain that no conclusions can be drawn from them. These are the best series (see appendix 2) that we have. The existence of the medieval warm period and the little ice age have been confirmed by many studies around the world and are not seriously challenged anymore. It can be safely stated that the IPCC’s estimated climate sensitivity range can be falsified by the best evidence that we have at the time of writing.
The IPCC’s position is that climate sensitivity measurements deduced from the LGM and volcanic activity that do not include any solar multiplier effect and are based on short wave solar radiation can be assumed to apply to Long Wave Radiation from AGHGs and changes in TSI at the sun’s surface that include possible solar multiplier effects.
This paper proposes that the IPCC’s position is not consistent with our best millennial temperature records nor is it consistent with Green House Gas Forcing and temperature rise in the 20th century (Fig. 1) without unrealistically large aerosol cooling. The IPCC’s position is particularly inconsistent when it is noted that aerosol levels have fallen over the last 20 years at a time when temperature rise has abated.
All the available data is neatly reconciled and consistent if we are prepared to accept that the earth’s climate sensitivity is different for long wave greenhouse gas forcing than it is for short wave solar forcing. It is, in fact, unlikely that these two would have the same sensitivity and there are good physical reasons why they wouldn’t.
PHYSICAL EVIDENCE
1. The existence of a cosmic ray effect on temperature has been debated for some time now and would explain the different sensitivities described in section “A” and section “B”. This is discussed in Shaviv 2005, “On Climate Response to Change in Cosmic Ray Flux and Radiative Budget.” Certainly the existence of some form of solar multiplier is supported by the evidence of the last millennium (section “A”) when it is compared with the IPCC’s sensitivity (section “B”). The IPCC’s climate sensitivity is derived from LGM and volcanic measurements that don’t include any solar multiplier effects as they are caused by changes at the earth’s surface as opposed to changes at the sun’s surface.
2. The climate response time is the time it takes for the atmosphere to respond to a change in forcing and is dependent on sensitivity and the amount of ocean mixing. Hansen, Sato and Kharecha, “Earth’s Energy Imbalance and Implications”, say “On a planet with no ocean or only a mixed layer ocean, the climate response time is proportional to climate sensitivity. ………..Hansen et al (1985) show analytically, with ocean mixing approximated as a diffusive process, that the response time increases as the square of climate sensitivity.”
If it can be shown that a change in the Long Wave Radiation from AGHGs has a shorter response time than a change in Short Wave Solar Radiation, then this would imply a lower climate sensitivity for changes in AGHGs than you would expect from changes in solar forcing.
It is well known and accepted physics that Long wave radiation from GHGs only penetrates the oceans to a depth of a fraction of a millimetre. Water is almost totally opaque to these wavelengths. Short wave solar radiation, on the other hand, penetrates water to a depth of 10 meters or more and is, therefore, readily involved in ocean heating.
There is clearly a significant difference in response times between Long wave radiation from AGHGs and the Short wave solar radiation used by the IPCC to calculate their sensitivity. Long wave radiation is returned almost immediately to the atmosphere while Short wave solar radiation is largely absorbed by the ocean and takes much longer to find its way back to the atmosphere on average.
It is entirely logical that shorter response times would equate to lower temperature sensitivities at equilibrium. There would quite obviously be less energy in the pipeline as the oceans are not warmed significantly by AGHG’s.
The IPCC and others argue that the warming of the top fraction of a millimetre by AGHGs prevents energy from escaping from the deeper ocean and, therefore, effectively has the same response time as solar radiation. This position is shown to be not correct by the simple experiment outlined in Appendix 3.
3. As you would expect the IPCC’s models and predictions are already starting to fail as a result of them using the wrong wavelength to estimate AGHG forced climate sensitivity. James Hansen’s catastrophic predictions to the USA congress in 1988 are compared with actual temperature in Fig. 9. They clearly don’t correlate.
Fig. 9 James Hansen’s 1988 predictions to the USA congress compared with actual temperature.
Here is a quote from the IPCC’s 2001 TAR, “..anthropogenic warming is likely to lie in the range of 0.1°C to 0.2°C per decade over the next few decades”, and another from the IPCC’s 2007 4AR “For the next 2 decades, a warming of about 0.2°C per decade is projected”. The earth’s temperature has remained level or fallen since both of these predictions were made.
APPENDIX 1
Fig. 1 AGHG Forced equilibrium temperature using the IPCC’s sensitivity based on #2 (LGM and volcanic) and compared to actual temperature as measured by the NOAA since 1880. The upper IPCC limit assumes a climate sensitivity of “X” = 1.2, the IPCC central prediction assumes “X” = 0.8, and the lower IPCC limit assumes “X” = 0.4.
The method used to plot this graph;
1. A preindustrial CO2 concentration of 280 ppm was assumed. CO2 concentrations since 1880 were taken from the IPCC pre 1960 and from Mauna Loa after 1960.
2. CO2 Forcing was calculated using the widely accepted formula ;
rF = 5.35 x ln(C/C0) wm-2
Where “C” is the current CO2 concentration and “Co” is the initial CO2 concentration. This formula is the basis for the IPCC’s position that a doubling of CO2 concentration will produce a Forcing of 3.71 wm-2. i.e. rF = 5.35 x ln (2) = 3.71 wm-2.
3. Based on the IPCC’s TAR and 4AR reports, the CO2 forcing was then multiplied by 1.66 to give the total forcing of all the AGHGs (NO2, CH4, Halogens etc.) See Fig. 5.
4. The IPCC’s equilibrium temperatures were then calculated using the IPCC’s sensitivity factors, 0.4 (lower), 0.8 (central), and 1.2 (upper). i.e. The IPCC’s central predicted equilibrium temperature for a doubling of CO2 is, therefore, 0.8 x 3.71 wm-2 or approximately 3.0°C.
5. All graphs were then zeroed at 1880, the time when relatively accurate thermometer temperature measurements commenced.
APPENDIX 2
The four main millennial temperature series summarised in Fig. 4.
Fig.10 Temperature series for the last 1000 years. Ljungqvist 2010 (Black Line), Loehle 2008 (Blue Line)
Fig 11. Moberg 2005 1000 year temperature record including more recent instrumental records.
Fig. 12 Mann 2008 EIV 1000 year temperature series.
APPENDIX 3
The simple experiment, attributed to Tallbloke, that proves that GHG increases do not significantly warm the oceans.
Konrad: Empirical test of ocean cooling and back radiation theory
Posted: August 25, 2011 by Tallbloke in atmosphere, climate, Energy, Ocean dynamics 68
Some background –
Willis Eschenbach had a guest posting over at WUWT in which he claimed that LWIR could heat Earth’s oceans. Myself and several others on the thread contended that this LWIR was likely to be stopped by the evaporative skin layer and would not slow the exit of heat from the oceans. Numerous requests for empirical evidence to support Willis’s claim only resulted in one inapplicable study used by the “Hockey Team” to support such claims. After several hundred comments without empirical evidence being offered, I gave up reading and designed and conducted an empirical experiment that shows that any effect of backscattered LWIR on the cooling rate of water would be negligible.
What follows is an edited version of the experiment design and results as posted on the WUWT thread. I would encourage others to conduct similar experiments to check my results. The equipment required is not overly expensive and the results can be observed in minutes. The results appear to show the measurable difference between reflecting LWIR back to warm water when it is free to evaporatively cool and when it can only cool through conduction and radiation.
What is required –
– Two identical probe type digital thermometers with 0.1 degree resolution
– Two identical insulated water containers. I used rectangular 200ml Tupperware style containers, insulated on their base and sides with foil and Styrofoam. I cut away the clip on rim from each lid to create a frame to clip down cling film for Test B of the experiment.
– One IR reflector. I used an A4 sheet of 10mm Styrofoam with aluminum foil attached with spray adhesive.
– One IR window. I built an A4 size “picture frame” of 10mm square balsa wood strips and stretched cling film over it.
– One 1 litre measuring jug
– Two small identical computer fans. I used Suron 50mm centrifugal blowers powered by a 6v gel cell battery
– Extra cling film
– Optional extras – kitchen timer, an A4 ”dark cool sky” panel of matt black aluminum with peltier cooling, glamorous lab assistant of choice.
What to do –
– Position probe thermometers in identical positions in both water containers. I placed the tips 10mm below the water line by drilling force fit holes in the sides of the containers.
– Position IR reflector and IR window 50mm above either water container. You may need to build two Styrofoam side walls, but air must be free to move over the surface of the water. (The use of the IR window is to ensure that air flow is similar over each water container.)
– Position the computer fans to blow across the water surface of each container, but do not turn on.
– Fill jug with warm water, stir, then fill each water container from the bucket. I used water around 40C as the ceiling was around 18C not a 3k sky.
– When and equal amount of water is in each container, turn on the computer fans.
– Observe the temperature change over time for each tank. Less than half an hour is required for such a small amount of water. You should observe that both tanks cool at the same rate (TEST A).
– Now the important bit – Repeat the experiment, but this time lay a small sheet of cling wrap on the surface of the water in each water tank. This allows cooling through radiation and conduction but prevents evaporation. You do not need the computer fans on in this test. You should be able to observe that while both containers cool slower than before, water under the IR reflector cools slowest (TEST B).
Interpretation –
In TEST A the water cools more quickly, however the two water containers temperatures remain very close to each other over time. This indicates that backscattered LWIR has a very limited effect on the rate of cooling for water when it is free to evaporatively cool.
In TEST B both water containers cool more slowly than Test A, but a divergence in temperature between the two water containers is readily detectable. The container under the foil sky cools more slowly than that under the cling wrap sky. This indicates that backscattered LWIR from a warm material can slow the rate at which that material cools, if radiation and conduction are the only methods for cooling.
Test A represents the evaporative cooling conditions in the real oceans. Test B represents how the climate scientists have modeled the oceans with regard to backscattered LWIR. From what I have observed, backscattered LWIR can slow the rate at which substances cool. However in the case of liquid water that is free to cool evaporatively this effect is dramatically reduced. It would appear that including the oceans in the percentage of Earth’s surface that could be affected by backscattered LWIR may be a serious error. Earth’s oceans cover 71% of the planet’s surface. If backscattered LWIR cannot measurably affect liquid water, then CO2 cannot cause dangerous or catastrophic global warming.
I have conducted further tests using a “cold sky” panel cooled with ice water over the top of the cling film IR window. While the temperature divergence in the evaporation restricted test B does not appear faster, it does appear to diverge for longer.
I would encourage others to conduct similar empirical experiments and share their observations. I would be interested in comments in further experimental design, or empirical evidence related to the LWIR question.
Typical TEST A
| Time | Cling Wrap Screen | Foil screen |
| 0 | 37.1 | 37.1 |
| 5 | 33.2 | 33.2 |
| 10 | 29.4 | 29.4 |
| 15 | 27 | 26.9 |
| 20 | 25.5 | 25.5 |
| 25 | 24.5 | 24.5 |
Typical TEST B
| Time | Cling Wrap Screen | Foil screen |
| 0 | 38.2 | 38.2 |
| 5 | 36.3 | 36.6 |
| 10 | 34.8 | 35.3 |
| 15 | 33.5 | 34.2 |
| 20 | 32.6 | 33.4 |
| 25 | 31.5 | 32.6 |
Fascinating post. Thanks. Wish I had time to comment.
I’m industrial boiler designer. I just wonder what absorption factor they use for CO2 or water vapor in atmospheric temperatures. When we design boilers and measure them we can’ t get any ir-radiation from clean fluegases (a little from hot particles) if temprature is below 600C. There is approx 12% CO2 in fluegases. Max absorption factor from this is 0,2 at 1500C, partial pressure 0,12 atm. When paritial pressure is 0,0035atm we can’t calculate any absorption factor for CO2 in 130C. Atmosphere is much colder in all places on earth than this. Gases don’t absorb IR-radiation in these temperatures nor CO2, if they don’t absorb then they can’t emit it, so what the hell is backradioation or radiative forcing? There might some misunderstanding what means absorption spectrum, that is definately not same as energy transfer.
Jim Cripwell says:
April 6, 2013 at 3:52 am
From the paper I read “The IPCC’s position is that climate sensitivity measurements” Assuming this is referring to the climate sensitivity of CO2, please note that, res ipsa loquitur, the climate sensitivity of CO2, however defined, has NEVER been measured, so this statement is nonsense. There are NO climate sensitivity of CO2 measurements; none whatsoever. Warmists will not admit that the CS of CO2 has never been measured, and as a result, the important implications of thsi fact cannot be properly discussed.
############################
Yes it has Jim.
“””””…..ABSTRACT
The Earth’s feedback response to warming is independent of the nature of the forcing that caused that warming………””””””””””
Well I would reject this premise, as baseless and unsupportable.
For starters, we have absolutely no idea, what: “The Earth’s feedback response to warming” even is.
How many highly touted climate models are there? 13 or so isn’t it. And they don’t even agree with each other, and none of them agree with observed experimental data.
Having said that, I have to thank Bob, for the effort he must have put into this presentation, and all the reported “information” he has assembled.
I can’t agree with much of what is stated in the presentation. This for starters makes my flesh creep:
“””””……
Climate sensitivity is the temperature increase at equilibrium for each Watt per square meter of forcing or “X” in the following equation. X°C/WM-2 ……”””””
The earth is never at equilibrium; any kind of equilibrium, and certainly not thermal equilibrium.
The earth rotates once every 24 hours, and as a result, most spots on the surface or in the atmosphere undergo wild thermal changes every day.
Bob says “Climate Sensitivity” Is “Temperature increase” per “increment of forcing”
What Temperature ? and where is the increment of irradiance measured ?
So what happened to the oft stated definition of “climate sensitivity”, apparently due to the late Stephen Schneider of Stanford,, that climate sensitivity is the slope of the straight line graph of earth surface Temperature, versus the logarithm of the (well mixed) atmospheric CO2 abundance ??
Well either one is somewhat nonsensical.
But how about that demonstration of LWIR slowing of water cooling. In the real world, that LWIR radiation comes from an atmosphere that is unrestricted and free to move around due to thermal influences. So how do you compare that to a setup, that prevents the air close to the cooling surface ( that is warmed by it), from freely moving to somewhere else, as happens in the real world.
That LWIR from the surface warms the atmosphere, is not a controversial claim. The laws of conduction and convection, do not seem to encourage any non-radiative thermal processes, to transport heat from that warmed atmosphere back to the surface.
That leaves only EM radiation as an energy (not heat) transport mechanism to try slowing the cooling rate. And the appropriate spectrum of EM radiation, and the appropriate spectral radiance, would be similar to that emitted from a bottle of cooled drinking water; certainly not what a 100 Watt light bulb, or common “heat lamps”, often used in other demonstrations. These sources emit about 10,000 times the total radiance, of thw water bottle.
So I don’t agree with the premise Bob laid out at the start; nor with much of what is later asserted.
I still do applaud the effort, and all the work.
Nick Stokes says: April 6, 2013 at 2:40 am
AND
Nick Stokes says: April 6, 2013 at 5:05 am
AND
Nick Stokes says: April 6, 2013 at 7:10 am
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Nick
There is a problem here.
The absorption characteristics of LWIR in water are governed by the optical physics. I do not understand there to be any dispute that about 50% of all LWIR is fully absorbed within just 3 microns of water.
As I explain above (April 6, 2013 at 7:35 am ), due to the omni-directional nature of DWLWIR, approximately 50% is fully absorbed within just 2 microns.. But nothing really turns on that refinement. I am quite happy to consider the 50% within 3 micron absorption.
I recall (it was probably about a year ago) that YOU, in response to one of my comments, calculated that if about 160 W m^-2 is absorbed within the first 3 microns of the ocean (this is 50% of the figure used by Willis for average DWLWIR) it would mean that the first 3 microns would absorb so much energy that it would give rise to about 15 to 16 metres of rainfall. You did not dispute the absorption characteristics of LWIR and I do not significantly join issue with your math calculation.
This, is of course, underlined my very point when I was pointing out that there is a problem with DWLWIR. The problem is this, if DWLWIR exists in the quantity claimed, and if it is capable of performing sensible work in the ocean environ, why are we not seeing copious amounts of evaporation and hence rainfall? This would be the inevitable result unless the DWLWIR can be sequested to depth at a rate faster than the rate at which it is absorbed in the first few microns and at a rate faster than the evaporation which would thereby resuult.
I thnk that you accept that the energy absorbed cannot be sequested to depth by conduction since you accept that the energy flux operates in an upward direction in the first few millimeters of the ocean.
So the question is this, can the slow mechanical process of rolling waves, and/or ocean overturning sequester the energy being absorbed in the first few microns at a rate faster than it is being absorbed?
If it cannot sequester to depth at a faster rate than the rate of absortion then the inevitable consequence is evaporation. The amount of evaporation would be substantial because of the amount of energy (160 W m^-2) being absorbed.
So what eveidence is there that the top micron of the ocean can be overturned? Indeed, what is the minimum thickness of water required not to break the over-turning process? What is the rate of overturning compared to the joule second rate of absorption and evaporation? What is the difference in daytime rate and nighttime rate?
Finally, the idea that one cannot do a useful experiment does not carry weight. There are very large model tanks used for ship design. These can replicate waves and swell. The atmosphere can be made windy with wind generation machines. It would not be difficult to replicate the tropical ocean (water at about 29degC with air temp at about 29 deg, to which 255K LWIR can be bombarded and then the temperature profile of the water measured.
Your argument about the ocean freezing is circuitous and does not shed light on the real life energy budget of the ocean. It does not answer whether the energy budget for the oceans is that they are receiving: 170 W m^-2 (solar) + 320 W m^-2 (DWLWIR), and are losing 390 W m^-2 (surface radiation) and 100 W m^-2 (sensible heat/convective/evaporative losses), thereby balancing at 490 W m^-2, or whether it is the null hypothesis energy flux position that the oceans receive: 170 W m^-2 (solar), and are losing 70 W m^-2 (radiation loss) and 100 W m^-2 (sensible heat/convective/evaporative losses), thereby balancing at 170 W m^-2, The oceans do not freeze irrespective of which energy budget is correct.
Rud Istvan:
In your post at April 6, 2013 at 7:58 am – much of which I agree – you say
Allow me to correct your statements which I have quoted.
The derived value for GHG sensitivity is even below that of Lindzen and Choi (2011), which demonstrates the Large size of the existing negative feedback, and confirms the finding of low GHG sensitivity Idso obtained from his ‘8 natural experiments’
http://www.warwickhughes.com/papers/Idso_CR_1998.pdf
What is known from observation (even though much of it is ignored by the IPCC including in the AR4) is that the water vapor feedback is obviously negative or we would not exist. The empirically determined climate sensitivity to GHGs is much less than the variety of values used as fudge factors in the models and are reported by Kiehl as shown in his Figure 2.
http://img36.imageshack.us/img36/8167/kiehl2007figure2.pngb
(ref. Kiehl JT,Twentieth century climate model response and climate sensitivity. GRL vol.. 34, L22710, doi:10.1029/2007GL031383, 2007).
Richard
About the experiment presented above (http://wattsupwiththat.files.wordpress.com/2013/04/image14.png). I do not see the conclusion about back radiation effect as justified. The covers above the containers are different and it is easy to assume, that the cover on the right is a worse heat conductor then the one on the left, and therefore the air under the right one would be a little bit warmer, thus making the cooling of water slower. This effect is similar to the one in the R.W.Wood experiment (1909), where the glass lid did produce a slight difference in temperature (under 1C), but was also a worse heat conductor, than the rock salt lid.
Oh cripes, not this BS again. I don’t care how much back radiation you have, YOU CANNOT HEAT A WARM OBJECT WITH A COOLER ONE! … You can not do so in this UNIVERSE!…
SHEEESH….
It is often not sufficiently appreciated that the air over land is very different to the air over oceans. The air over land is often significantly cooler than the land temperature (especially in daytime) but the air over the ocean is at nearly the same temperature as the ocean underneath.
It is the ocean that warms (and keeps warm) the air above.. Because of this, there is little diurnal range.
If GHGs lead to DWLWIR then one would expect far more DWLWIR over oceans (than over land at the same latitude) since ocean air is humid containing high levels of water vapour (the ocean evaporate).
I would suggest that this casts doubt on the relevance and accuracy of the average energy budget put forward by Willis, ie., the oceans are receiving: 170 W m^-2 (solar) + 320 W m^-2 (DWLWIR), and are losing 390 W m^-2 (surface radiation) and 100 W m^-2 (sensible heat/convective/evaporative losses), thereby balancing at 490 W m^-2.
Surely, the position must be that due to the high level of water vapour immediately above the oceans and the GHE of that water vapour, the oceans must be subject to more than the average 320 W m^-2 (DWLWIR), used by Willis, and if so, this begs the question, why are the oceans not heating up?
If DWLWIR has sensible energy capable of performing sensible work, why does morning dew not evaporate. we must have all seen in winter, a hollow half of which is in the shade most of the day. Within 1/2 an hour or so of sun up, dew in the hollow is burnt off whereas dew on the shady side side of the hollow can linger for most of the day. This is so, notwithstanding that morning winter sunlight is weak and if you compare the total energy imparted onto the dew from say 1 hours worth of low solar power + DWLWIR with say 3 hours worth of just DWLWIR, the dew on the shady side of the hollow would have received more energy than was received by the dew on the sunny side of the hollow by the time the dew on the sunny side evaporated, and yet the dew on the shady side does not evaporate. Why is this? It is something which is frequently seen in the late autumn through to early Spring months, and is something with which we are all familiar.
Just a couple of points to ponder on for those that are interested.
CO2 Climate Sensitivity Vs. Reality
Arguments about climate sensitivity, on the part of “lukewarmers” opposed to the alarmists, are like arguments over who can use the least number of epicycles to explain the apparent paths of the planets in the night sky over time, assuming they really travel in perfect circular orbits: It is all in vain (not to mention out of date by more than 20 years, with respect to provably incompetent climate science).
Leonard Weinstein says:
April 6, 2013 at 7:45 am
“However, back radiation SLOWS the radiation cooling from the ocean, resulting in a higher equilibrium temperature than without it.”
I have a question about this assertion. I have seen it stated in several different places that a non-zero lapse rate is necessary in order to have a greenhouse effect. On the Science of Doom website, there is a post titled “Understanding Atmospheric Radiation and the ‘Greenhouse’ Effect – Part Four”. Figure 4 of that post shows how, in an atmosphere containing GHGs, the lapse rate affects the TOA radiative flux and also how the lapse rate affects DLR. (I am assuming that “DLR” is an equivalent term to “back radiation”.) When the lapse rate is 0 K/km, with all else being equal the DLR is at a maximum. At the same lapse rate of 0 K/km, the TOA flux is calculated as equal to the flux at the Earth’s surface, implying no greenhouse effect.
So as I understand it, SoD is saying that, under a zero lapse rate condition, a strong presence of back radiation does _NOT_ result in a higher equilibrium temperature. My conclusion would then be that back radiation has nothing to do with the greenhouse effect.
Do you see any flaw in this logic?
Climate Sensitivity:
Terry Oldberg says: April 5, 2013 at 11:25 pm
“…The notion that [there] is a “climate sensitivity” is scientifically nonsensical as this sensitivity is defined in terms of an equilibrium temperature but this temperature is not an observable….”
To this I would add that logic suggests that it is impossible to determine climate sensitivity from observational data until one knows and fully understands natural variation, and its bounds.
The reason for this is that until one knows the precise nature of natural variation, how it is acting and what its bounds are, it is possible that each and every variation in the temperature record is fully explained solely by natural variation and changes therein. At this stage, we cannot conclude that all the post 1850 warming was due to natural variation, the post 1880 cooling was due to natural varaition, the post 1920 warming was due to natural variation, the post 1940 cooling was due to natural variation, the post 1975 warming was due to natural variation etc.
It is even possible that climate sensitivity to CO2 is negative. This cannot be conclusively ruled out. For example, since we do not know enough about natural variation, it is possible that between 1940 and late 1970s its effect was entirely neutral and the post 1940 cooling is actually explained predominantly by the increasing CO2 levels and part by aerosol emiisions from power plants etc. Then post 1970s, natural variation was stronly positive so that it off-set the cooling effect of increasing CO2 emissions, the reduction in aerosols from cleaing up power plant emission also acted in a positve fashion, such that we then saw a net warming. Now as from the late 1990s. natural variation is slightly positive but with the negative effect of increased CO2 we are seeing neutral to possibly slightly falling temperatures.
I am not suggesting that the above properly explains the thermometer record, but it could do, and we cannot rule out such an explanation until such time as we can fully identify each and every forcing encompassed in the expression natural variation and whether they are positive or negative and the upper and lower bounds of each and every such forcing.
In conclusion, climate sensitivity will never be anything more than a guess untill we have a full understanding of natural variation and its bounds simply because until we have such knowledge, it is impossible to extract the signal (ie., climate sensitivity) from the noise (ie., changes in temperature brought about by natural variation)
Lead sentence of article:
“The Earth’s feedback response to warming is independent of the nature of the forcing that caused that warming.”
Ferdinand Engelbeen (April 6, 2013 at 2:04 am) commented on this:
“That is the basic rule of what the IPCC says […] But that can’t be true”
Agree. Ignorance &/or deception about the role of spatiotemporal pattern in flow. The usual trick.
“‘I’d like a martinus.’ ‘You mean a martini.’ ‘If I want two I’ll ask for them.'” (don’t know the skit author) LGM = Last Glacial Maximum–maxima is plural. –AGF
There is no doubt that an enormous amount of down IR (=to SI) goes to the ocean but it goes no deeper than the “black” skin. If the atmosphere were warming, its thermal mass would decrease the heat loss from the surface and warm the ocean, but the atmosphere has not been warming.
If well mixed GHG’s were warming the oceans such warming should be even, but all ocean warming in the instrumental period can be accounted for the Indian, the North Atlantic, and the Arctic Oceans.
squid2112:
At April 6, 2013 at 9:25 am you write in total
You have caught my interest because 10 minutes ago I heated the bacon for my sandwich in a microwave oven. Thus, I heated an object with a cooler one.
Until now I have not had a conversation with a being in another universe that operates under different laws of physics. I am fascinated by your universe, and there is much I would like to know about it. For example, do you have gravity there?
Richard
Paul Vaughan says:
April 6, 2013 at 10:29 am
=============================================================================
For example, although TSI due to orbital forcing varies only slightly when averaged globally, when the edge of the ice sheet gets an extra 80W/m^2 and local albedo changes from near 1 to near 0, the ice melts faster than it snows. The more we average, the more we ignore the pertinent processes. –AGF
Probably nobody wants to know but there are other effects that the sun does to the atmosphere, according to NASA, it makes it vary in size, that is volume. Now if the volume of the atmosphere varies with solar variations does this not reflect on both weather and climate?
http://www.nasa.gov/topics/earth/features/AGU-SABER.html
and
http://science.nasa.gov/science-news/science-at-nasa/2010/15jul_thermosphere/
or do all those computer models take this into consideration?
tckev says:
April 6, 2013 at 11:12 am
Probably nobody wants to know but there are other effects that the sun does to the atmosphere, according to NASA, it makes it vary in size, that is volume.
Not only that but a solar cycle also shifts the jet streams poleward at high solar activity and reverse together with the accompanying cloud and rain patterns (cause: more UV – more ozone – higher temperature in the equatorial lower stratosphere – more temperature difference between equator and poles at that height). The impact on regional climate in general is huge and may influence global climate. The influence of GHGs on the jet stream position is probably zero, despite recent claims (in Europe) that the sea ice melting of the Arctic influenced the jet stream position too and was the cause of the long winters here…
Several links:
http://onlinelibrary.wiley.com/doi/10.1029/2005GL024393/abstract
http://onlinelibrary.wiley.com/doi/10.1029/2005GL023787/abstract
http://ks.water.usgs.gov/pubs/reports/paclim99.html
http://nzclimatescience.net/images/PDFs/alexander2707.pdf
richard verney says:April 6, 2013 at 9:12 am/i
Richard, there is no need for the heat from LW to be sequestered. The overall heat flux is upward. In fact at each water level, on time average, the hat flux up balances the SW energy flux downward. There’s a balance to be achieved at the surface; without down IR the loss from the warm water would be more than insolation could supply. With down IR, there’s enough to cover evaporation too.
Regurgitation? I have a distasteful problem with references to “forcing function” and “feedback’, and particularly with “positive feedback”. These terms evoke some bad (although few) memories of my stint at the U.S. Submarine base on Midway Island until the war ended in 1945.
The entire western island (there were two of them within the reef) was covered with nesting gooney birds when I got there. Only the airstrip was kept clear of them (for obvious reasons.) They were also kept clear of a small patch of green grass that grew on imported black dirt around the old transpacific cable station, because it provided fodder for the single milk cow that provided fresh milk for the sick-bay residents, and sometimes as a special fresh-food treat for west going submariners.
The baby goonies provided an endless variety of entertainment, as they exercised their wings on the surface before learning to fly, then as they returned from their first flights, folded up their big wings and tried to land (er.. is-land?).
But the problem I am homing in on is that as the gooney babies were growing up in their nests on the sand,. their parents kept feeding them by regurgitating the glop from fish they had caught while out fishing for sustenance, swallowed, and had partially digested. It looked like ugly stuff while being regurgitated into the wide-open beaks of their babies.
So that is why I would prefer the use of the word “reaction,” as in Newton’s third law, instead of pejorative words such as “positive feedback” or “forcing function” — they just evoke an ugly memory of gooney-birds regurgitating dead, partially decomposed fish.
richardscourtney @April 6, 2013 at 10:52 am
“You have caught my interest because 10 minutes ago I heated the bacon for my sandwich in a microwave oven. Thus, I heated an object with a cooler one.”
uhmmm…
Hey guy your microwave oven doesn’t heated your your beacon at all, it was the electromagnetic field produced by its magnetron which being tuned up at the resonant frequency of the water molecular dipole heated your beacon.
Do you want a proof of what I say?
Well, put a piece of good insulating ceramic such as alumina or a good insulating plastic into you microwave oven, turn it on at the maximum power and wait all the time you want, but when you’ll open the oven the insulating material is still at the environment temperature.
squid2112 was quite right in his statement, except that he missed to tell that there is an overall condition: without external work/energy applied to the system.
Massimo PORZIO:
Your post top me at April 6, 2013 at 2:10 pm concludes saying
No! He was completely wrong as the example of my microwave oven demonstrated.
As you say, the energy transfer used by my microwave oven is conducted by electromagnetism. Similarly, the back-radiation to the Earth’s surface is conducted by electromagnetism.
In both cases there is an external source of energy: unless, of course, you want to claim the Sun is not a source of energy?
Richard
If the Earth’s surface is lumped as a simple swampy thermal model (and I know there are people who object to this), then from the discussion above solar radiation is 170 W/m2, LWIR is 320 W/m2, outgoing LW is 390 W/m2, and evaporation is 100 W/m2. This represents one point on our sensitivity curve. The problem is working out how these figures vary given changes in conditions.
The extra CO2 will increase the LWIR by 2 W/m2 or something like that. I suppose I have a bit of a problem with saying that this would not be absorbed by the swamps, because clearly the existing incoming LWIR of 320 W/m2 is absorbed, and there is no difference qualitatively between these 320 W/m2 and the extra 2 W/m2. If this 320 W/m2 was not absorbed, there would be a massive imbalance in the (170 + 320) = (390 + 100) energy flux budget.
Pretend the atmosphere is a perfect transmitter of long wave, and there is no greenhouse effect. Thermal equilibrium would be about 30 degrees (C or K) lower. So the effect of the extra 390 W/m2 back radiation is to raise the temperature by 30K. So a straight line fit suggests a sensitivity of something like 30K divided by 390 W/m2 gives 0.077 Km2/W odd, which is far lower than anything suggested by the IPCC.
Of course a straight line fit is unsupportable. Convection kicks in to make the curve non-linear. However the effect of this added non-linearity is to move even more heat away from the surface as a function of temperature, so the sensitivity is far lower even than 0.077.
“””””….. richard verney says:
April 6, 2013 at 9:12 am
Nick Stokes says: April 6, 2013 at 2:40 am
AND
Nick Stokes says: April 6, 2013 at 5:05 am
AND
Nick Stokes says: April 6, 2013 at 7:10 am
//////////////////////////////////////////////////////
Nick
There is a problem here.
The absorption characteristics of LWIR in water are governed by the optical physics. I do not understand there to be any dispute that about 50% of all LWIR is fully absorbed within just 3 microns of water.
As I explain above (April 6, 2013 at 7:35 am ), due to the omni-directional nature of DWLWIR, approximately 50% is fully absorbed within just 2 microns.. But nothing really turns on that refinement. I am quite happy to consider the 50% within 3 micron absorption……”””””
Well I’d like to see your references to papers asserting that result, over which you assert there is no dispute.
I would suggest that just one peer reviewed paper asserting something different, would constitute a dispute. Remember Eienstein said only one contrary result overrides a thousand supporting ones. ( or words to that effect.
So I offer G.C. Ewing (ed.), “Oceanography from Space.” Woods Hole Oceanographic Institution, Woods Hole, MA. WHOI Ref. No. 65-10, April 1965.
This is ref 3-91 , and fig 3-113 in chapter 3 of “The Infra-Red Handbook, published by theInfrared Information Analysis Center of the Environmental Research Institute of Michigan, for the Office of Naval Research, Department of The Navy.
So what does fig 3-113 say ?
Well for starters, it shows that sea water has its maximum absorption of EM radiation at 3.0 micons wavelength; not exactly LWIR, but probably not near IR either.
at 3.0 microns, sea water has an absorption coefficient of about 8,000 cm^-1 (hard to read, but 7-9 range) So that means that the 1/e (37%residual) absorption depth is 1.25 microns.
So the 1/2 power point is 70% of that (0.6931) , or about 0.866 microns. Now that is a peak absorptance. There are local minima at about 4.0 microns; 40 times lower absorption coefficient,(200cm^-1) and at about 2.3-2.4 microns, maybe 8-10 times lower than that (20 cm^-1)
So that’s the highest absorptance pak, and barely long wave.
The second highest peak comes at about 6.0 microns wavelength, now real LW, but only 1% of atmospheric sourced LWIR occurs shorter than about 5.0 microns. So that second peak is about 2,000 cm^-1, so now a 5 micron 1/e depth, and again a narrow peak..
From 7-10 microns, about where the atmosphere window is, we get about 900 cm^-1, so about 11 microns 1/e depth. From that 900 low, at 7 microns, it climbs slowly to about 3,000 cm^-1, and then drops about monotonically , reaching 100 cm ^-1 which they call a 0.1 mm “optical depth” at about 600 microns wavelength. So optical depth, is what they call the 1/e residual depth, and over the 5-80 micron wavelength range of atmospheric LWIR, the optical depth, is much more like 10 microns plus, than 2.0 or 3.0 microns.
Three times the optical depth, gives 95% absorption; 5% transmission, so 30 microns, and five times optical depth or 50 microns depth, gives 99% absorption, 1% residual transmission.
Yes atmospheric LWIR is trongly absorbed in sea water, but that 2-3 micron figure for 50% loss, is more like the maximum for the whole 3 micron wavelength line, than for the whole LWIR spectrum.
This data, which is of great importance to seafarers, and Naval folks, is not recent news, it has been well known for about a half century.
So nyet on the 2-3 micron “skin”.
But hey! I agree completely on the basic concept; just let’s not exaggerate, what in reality, is already dramatic enough.