Guest post by John Kehr from: The Inconvenient skeptic
There are many times when I am putting together articles that I need to compare the results of my research to the models of the theory of Anthropogenic Global Warming (AGW). In this manner I can contrast the results and predictions directly. This way I understand how the different views relate to each other.
Recently I was trying to find the total amount of energy (forcing) that the warmists claim CO2 is responsible for in the atmosphere. The reason I wanted this is because I have recently completed my full analysis of absorption and I wanted to compare my results to the warmist views. While this article is not about my results, it will focus on some interesting results that I found using their models. Because I was searching for the warmist views about energy I was using information from their sites (and citations of course). While that might seem strange, they generally have lots of good information there.
The starting point is the basic equation they use to determine the forcing caused by a change in CO2 concentration.
CO2 Forcing Equation
This equation provides the amount of energy in W/m2 that a difference in two CO2 concentrations should cause.
While looking for the total forcing of CO2 in the atmosphere, I found an interesting article on the Skeptical Science (SkS) site that had an answer to my question (citation). They state that the radiative flux caused by CO2 is 32 W/m2. I will use the information from that article several times. When I compare the energy calculated by the forcing equation using CO2 levels of 1 ppm and 390 ppm I get a result of 31.9 W/m2. So far things are looking consistent for the theory of AGW. Here is a chart of the forcing from 1 ppm to over 1000 ppm.
Proposed Model of CO2 Forcing
The next step is to determine how much warming this energy causes. For this I use the next important equation that the AGW model uses. That is the climate sensitivity.
Climate Sensitivity: Warming caused by Forcing
Again I found lots of discussion and references at the SkS website (Hansen et al. 2006) where they provide their views about climate sensitivity. This equation is straightforward and simple to decipher. They generally calculate it by looking at a period of time with a temperature change and then estimate the change in forcing. For example if increasing CO2 caused a forcing of 2 W/m2 and the observed temperature change was 5 °C, then the climate sensitivity would simply be 2.5 °C /(W/m2).
One thing to be aware of is that the sensitivity is usually not shown directly. Most warmist publications display the results in terms of temperature change that will happen as a result of forcing. For example the most commonly used quantity for climate sensitivity is 3.0 °C for a doubling of CO2. To determine the climate sensitivity they are using it is simply:
λ = (3°C / 3.7 W/m2 ) = 0.81 °C/(W/m2)
I am going to use the direct climate sensitivity instead of the temperature effect that a forcing will cause. This will make my numbers look a little different, but here is the conversion.
Proposed Range of Climate Sensitivity
When comparing climate sensitivity it is very important to know exactly which form is being used. I will be using the actual climate sensitivity instead of the CO2 doubling form. The best way to check is to look at the units being used.
The most common estimate is the 0.81 °C/(W/m2). That is what corresponds to the 3 °C temperature increase for a doubling of CO2. The full range is what I have shown in the table. Some estimates do go a little higher or lower, but the 0.43-1.13 °C/(W/m2) is the most widely accepted range.
SkS puts the climate sensitivity at the 0.81-0.92 °C/(W/m2). I am going to use the 0.81 °C/(W/m2) as the default value for the warmists as it is the most commonly used value.
So far all of this seems perfectly reasonable and hopefully acceptable. This is also where the wheels start to come off.
I decided to look at another method to determine the climate sensitivity. I am troubled by the method normally used because it is very hard to know the exact forcing and cause of the temperature change. So I decided to use what should be a less controversial method, but somehow I doubt it works out that way.
I decided to use the total Greenhouse Effect (as the ΔT) and then the energies involved. The total Greenhouse Effect is perhaps the least controversial aspect of the Global Warming debate. I will use the normally accepted value of the Greenhouse Effect as 30 °C.
Now by using the climate sensitivity value it is possible to compare what portions of the Greenhouse Effect (GHE) are caused by different components. Since the accepted forcing value for CO2 is accepted as 32 W/m2 it is now possible to determine the total impact that CO2 has on the total GHE.
ΔT = (0.81°C/(W/m2)) * 32 (W/m2) = 25.9 °C
While that might not immediately seem unreasonable. The entire stated effect of the GHE is 30 °C. So according to the accepted climate sensitivity and CO2 forcing equations, CO2 accounts for 86% of the total GHE.
So all other factors in the Earth’s climate account for 14% of the GHE and CO2 by itself accounts for the other 86%. This can also be compared to the number of CO2 doublings that take place from 1 ppm to 390 ppm. That is roughly 8.6 CO2 doublings (1,2,4,8,16,32,64,128,256,390 ppm). Using 8.6 doublings from 1 ppm gives 25.8 °C. So their model is coherent, but saying that CO2 causes 86% of the GHE is extremely incorrect.
This means that the methods being used for determining temperature change based on forcing and climate sensitivity are flawed. Any result that puts CO2 at 86% of the GHE is wrong. Earlier I showed that the forcing model and the accepted total forcing have a good match. That would indicate that the problem is with (at least partially) the estimated climate sensitivity.
So I worked backwards. Assuming that the total temperature change caused by the GHE is 30 °C and then the total energy inputs are the total forcing. The total GHE is not very controversial. Very few people will argue that the Earth is not warmer as a result of the atmosphere. Without the atmosphere the Earth would be around -15 °C and with the atmosphere it is currently about 15 °C. That 30 °C difference is caused by the insulative effect caused by the atmosphere.
That leaves forcing as the problem in determining the correct climate sensitivity. The same article that stated CO2 as 32 W/m2 also stated that water vapor causes a forcing of 75 W/m2. If I assume that water vapor and CO2 are the ONLY factors I get a total forcing of 107 W/m2. This would indicate:
λ(30%) = (30°C /107W/m2) = 0.28 °C/(W/m2)
Already using very poor assumptions the climate sensitivity is already much lower (by almost 3x) than the accepted value. This still puts CO2 at 30% of the total GHE, so even this estimate for climate sensitivity is still too high.
The normally discussed range of CO2 effect on the GHE is 9-26%. Assuming that the 32 W/m2 remains accurate for the forcing magnitude of CO2 results in climate sensitivities of:
λ (9%) = (30°C / 356 W/m2 ) = 0.08 °C / (W/m2 )
λ (26%) = (30°C / 123 W/m2 ) = 0.24 °C / (W/m2 )
At 9% of the GHE the climate sensitivity must be 10x lower than what is currently accepted. There is one more possible scenario that I want to cover.
If I look at the Radiation Budget (Kiehl, Trenberth 1997) I get a total forcing from the surface to the atmosphere of 452 W/m2. That would include the energy from evaporation, convection and radiative transfer and subtracting out the open window of 40 W/m2. If I use the 32 W/m2 for CO2 with that total energy then CO2 accounts for 7% of the total GHE. Then the climate sensitivity is:
λ (total energy) = (30°C / 452 W/m2 ) = 0.066 °C / (W/m2 )
That is what the real lower limit of the climate sensitivity is. The flaw in the estimates for climate sensitivity is the assumption that all temperature change is caused by the greenhouse gas forcing. If the climate was as sensitive as the much higher estimates currently in use are, the Earth would be a very unstable place as small changes in energy would cause large changes in temperature.
Using the total GHE determined climate sensitivities, here are the CO2 doubling effects on the climate.
GHE Determined Climate Sensitivities
What this shows is that trying to determine the climate sensitivity from a change in measured temperature and then assuming it was caused by a particular forcing is incompatible from the determination of climate sensitivity from the actual GHE. In choosing between methods it is the GHE that is a known quantity. Since the measurements have been done to determine the individual parts of the GHE, that seems to be a much more reliable method than “assuming” that a particular forcing caused a certain change in temperature.
The IPCC and the general AGW method of determining climate sensitivity is about an order of magnitude different than the method of using the total GHE and then calculating the components. This is a significant scientific disparity.
The difference the climate sensitivity makes to the temperature projections based on increasing CO2 concentrations are significant. Assuming the same CO2 forcing while using the different climate sensitivity values results in the following effects of CO2 on the global temperatures.
Red: The AGW accepted climate sensitivity of 0.81 (3C for doubling) Green: Climate sensitivity of 0.28 (1C for doubling) Blue: Climate sensitivity of 0.066 (0.24C for doubling)
The total GHE of 30 °C is incompatible with the currently accepted IPCC values of climate sensitivity and CO2 forcing. In order for the GHE to be compatible, the total effect of the greenhouse would have to be closer to 100 °C which would result in a global temperature of ~85 °C. This strong overstatement of the climate sensitivity substantially weakens the idea that CO2 could cause measurable change in the Earth’s climate, much less the type of danger that is often being stated.
This does not mean that CO2 is not a significant portion of the Earth’s greenhouse, but it does limit the role that it plays in the total GHE. The climate sensitivity is what prevents the sum of the parts from being greater than the whole and the sum of the parts cannot be greater than the total observed GHE. If the current estimates of CO2 forcing and climate sensitivity do not fit within the parameters of the total GHE effect, those estimates must be incorrect.
How much of CAGW theory is based on the “T” factor of energy in the atmosphere?
I see it basically like a freeway. If the incoming traffic (TSI) is constant, but the speed of certain cars reduced by the cops (GHG) the total traffic, (energy/ temperature) increases.
In the above the atmosphere is the freeway, and the TSI is incoming traffic. GHG are the cops that slow down certain red sports cars, (LW radiation) thus increasing the energy or density of traffic on the freeway. However, our earth has more then just freeways. We have many side streets that reduce the speed (residence time of incoming radiation) of traffic more then anything on the freeways. (atmosphere),
These slower streets are the land and Ocean, and what happens here effects the residence time (speed) of vehicles more then what happens on the freeways. A photon of SW radiation entering and penetrating the ocean slows down dramatically compared to the freeway of the atmosphere. So the total traffic flow (earths energy budget) depends on the time spent on all streets, not just the freeways, or atmosphere.
If water vapor and clouds increases in the atmosphere, (more cops enter the freeways)
less traffic enters the side streets, the oceans, and even though freeway traffic increases due to more freeway cops, side street traffic is more sparse (cooling) and total time in the traffic system is reduced even though the freeway traffic is temporarily increased.
I am just s trying to wrap my non science educated brain around this so any thoughts helping me see if I am driving in the right direction here are appreciated.
The author doesn’t even understand the first thing about what a doubling of CO2 actually means. Tom Kehr says in the original post:
So all other factors in the Earth’s climate account for 14% of the GHE and CO2 by itself accounts for the other 86%. This can also be compared to the number of CO2 doublings that take place from 1 ppm to 390 ppm. That is roughly 8.6 CO2 doublings (1,2,4,8,16,32,64,128,256,390 ppm). Using 8.6 doublings from 1 ppm gives 25.8 °C. So their model is coherent, but saying that CO2 causes 86% of the GHE is extremely incorrect.
To say that CO2 ‘doubled’ when it went from 1ppm to 2ppm is a fine demonstration of his complete ignorance on the subject. When scientists refer to a doubling of CO2, they mean from the pre-industrial (ca. 1750) value of 280ppm to 560ppm (which, if we keep going the way we are now regarding the use of fossil fuels, will happen sometime around 2050). Anything below that value of 280ppm is essentially meaningless to us going forward. In fact, if you look at the CO2 levels derived from Vostok ice cores, the CO2 level has never been below 180ppm for the past 400,000 years, even during ice ages.
As Ammonite alludes to above, Tim Folkerts was spot on in his post that explains why you can’t consider CO2 in isolation. It (currently) contributes less than 20% to the greenhouse effect, but it is a very important effect in that it is one that mankind is primarily causing. And mankind is causing it because those ice core samples show that CO2 levels have never been above 280ppm for the past 400,000 years. A value of 390ppm is *unprecedented* in Earth’s recent history.
The extra warming caused by the additional CO2 allows the atmosphere to hold more water vapour, which leads to even more warming, etc. Then when (not if, but when) large areas of the permafrost start to melt as a result, this will release trapped methane into the atmosphere. And methane is an even more potent GHG than CO2 :-\
As Ammonite alludes to above, Tim Folkerts was spot on in his post that explains why you can’t consider CO2 in isolation. It (currently) contributes less than 20% to the greenhouse effect, but it is a very important effect in that it is one that mankind is primarily causing.
False.
Mankind’s CO2 emissions are only a small part of the total CO2. Completely stopping all increases will NOT change the world’s temperatures, but will directly and immediately harm many billions of innocents. Temperature change effect of trying to keep CO2 emissions at today’s levels? Less than 1/10 of one degree.
The past three year’s global recession is directly traceable to the democrat’s and liberal’s CO2 programs and energy policies.
No global model can work without assuming the massive multiplier effect of water vapor.
No global model can work without assuming – with no basis in measured global values! – a sulfur particle/aerosol limit between 1960 and 1980 to sunlight.
No global model has predicted the past 15 years of static temperature while CO2 has risen steadily.
No global model can account for the 60 year short term climate cycle.
No global model can account for the 800 year long-term cycle of the Roman Warming period, the Dark Ages, the Medieval Warming period, and the little Ice Age.
No global warming model is, therefore, correct in predicting anything about the year 2050, 2100, or 2150.
wayne says:
October 25, 2010 at 1:01 pm
“I am curious where you got the 4ºC average temperature for the oceans.”
I didn’t get it from here:
http://chalk.richmond.edu/education/projects/webunits/biomes/oclimate.html
but its calculation of 3.8C awfully close to my estimated 4C. Mine was just a back of the envelope calculation. Not sure where I got my starting numbers but I think it was here:
http://www.windows2universe.org/earth/Water/temp.html
90% of the water in the global ocean is below the thermocline and the temperature is a pretty consistent 3C. For the surface layer I used 16C and solved for the average ((9*3C)+16C)/10 = 4.3C and rounded down to 4C which I figured should be accurate enough since 16C is on the high side for the portion of the global ocean above the thermocline as it’s the average temperature at the air/water interface and declines from there as you go deeper.
“Jeff L says: October 25, 2010 at 11:56 am
“I would love see a warmist post on here an analysis of why this is not a correct analysis.””
If I have time, I would like to write one. I just doubt I will: this article is horrendously flawed, mainly because it confuses forcings and feedbacks and assumes linearity over a range where it is not justified e.g. the 3 C is because climate sensitivity is considered to be approximately linear pretty close to today’s temperature. This includes things like water vapour and cloud feedback.
If the Earth were at -100 C, there would be negligible water vapour/cloud feedback and the climate sensitivity calculated there is completely irrelevant to today.
By looking at total heating and dividing temperature by total heating, you confuse forcing and feedback. Without CO2, there would be effectively no atmospheric water vapour because by removing the CO2 you cause cooling. Water condenses out and Earth cools more – so the heating is actually a feedback to the CO2, not a separate radiative forcing.
If you add excess water vapour, it condenses out within weeks and can’t sustain warmer temperatures so it doesn’t act as a forcing.
Ian H says:
October 25, 2010 at 2:33 pm
“There is a problem in the argument here that should be pointed out. The forcing due to CO_2 cannot be exactly logarithmic, only approximately so in the region of concentrations not too different from now.”
Quite right. John Tyndall demonstrated it experimentally 150 years ago. At very low concentrations longwave absorption increases in a linear fashion. Basically the first longwave absorption is like picking the low hanging fruit – it gets progressively more difficult to capture and due to the nature of absorption and re-emission you’ll never capture all of it as some portion of the energy at the far end of your absorption column will be re-emission at the primary absorption frequency.
Everyone should really read the longwave absorption section on gases in Tyndal’s 1859 “Heat – A Mode of Motion” which is freely available in its entirety on books.google.com. Tyndal conducted thousands of experiments using different gases at different pressures with an ingenius experimental setup – for example he read the dial on his galvonometer using a telescope so that body heat didn’t muck up the energy being received by it. Another thing he did was use a second adjustable longwave energy source on the back-side of the galvonometer to keep the instrument its most sensitive linear range despite widely varying inputs on the front side of it. Just reading about his experimental setup with rock salt windows (rock salt, unlike glass, transmits longwave radiation with very little attenuation). It took a long time just to find a big enough monolithic rock salt crystal from which to cut and polish the column windows.
Effects of a total solar eclipse (George E. Smith says:
October 25, 2010 at 9:22 am ):
I made a very short study for what happened during the total eclipse in 11 August 1999 in Luxembourg: you may look here: Impact of Solar Eclipse
Concerning impact of total solar eclipse:
sorry: link was bad: here it is:
http://meteo.lcd.lu/papers/eclipse99/eclipse99.html
Tim Folkerts says:
October 25, 2010 at 2:05 pm
“4 C would be the average temperature thru the whole depth of the ocean.”
Correct.
“The surface itself would still be around 15 C.”
That depends on a whole bunch of factors. It’s 15C on average 15 thousand years into an interglacial period. During the peak of the glaciation cycle the surface is going to be largely ice with an average temperature well below freezing.
“And that 15 C surface temperature is all that matters for IR radiation to the atmosphere. (Kinda like rocks deeper down are much hotter, but that doesn’t affect the IR radiation either.)”
This is really really wrong. The ocean is fluid and although it mixes much slower than the atmosphere it does still mix through convection and it conducts reasonably well compared to rocks too. Rocks are nearly solid in comparison so you get no conduction and unlike water they are excellent insulators. There is no comparison in this regard between the earth’s crust and the global ocean.
The last comment should read “rocks are nearly solid in comparison so you get no convection“
What happens if we use the period 1940 to 1970 to determine forcing and sensitivity?
I thought so.
George E. Smith says:
October 25, 2010 at 3:46 pm
“By the way, I wish people would stop assigning significant albedo contribution to snow and ice cover (mostly in te polar regions) rather than to cloud cover which averages about 61% on earth (cloud cover, not albedo)”
Snow and ice cover is mostly near the poles, except for NH winter when it extends down quite a bit farther over the land surface. But that wasn’t my point. Interglacial periods during the last few millions years are roughly 1/10 the duration of the glacial periods. During the glacial periods snow and ice are not confined to near the poles. During that time a large fraction of the earth’s surface is covered year-round by glaciers and sea ice and there are very few clouds. At times in the earth’s history the coverage was 100% and these episodes are called “snowball earth”. Nobody quite knows what works to melt a snowball earth yet something does. My pet theory is that with most of the green plants gone and the ocean covered with ice there is no CO2 sink for the atmosphere so it remains constant. But underwater volcanoes keep right on chugging along belching CO2 into the ocean. Over the course of millions of years the pressure builds up under the ice like CO2 builds up in a bottle of homemade beer. If you put too much sugar in the bottle before you cap it the bottle will eventually explode. I think it might work like that with a snowball earth. Dissolved CO2 builds up in the ice-capped global ocean from volcanic emission until something, maybe an asteroid, comes along to break the seal then all of a sudden atmospheric CO2 level shoots up through the roof to 4000+ ppm and the greenhouse effect kicks into high gear melting the ice particularly near the equator. Green plants then recover quickly gluttonously feeding on the CO2 feast with little competition and lowering the albedo from snow level (85% reflectivity) to plant level (12% reflectivity) wherever they grow in a rapidly expanding range. And as sea ice melts that’s also a positive feedback as the ocean has single digit % reflectivity in most circumstances (high incidence angle and/or even a small amount of wave action).
@george (con’t)
There’s a big fundmental difference in the way clouds works as opposed to ice. Clouds form as the sunlight drives evaporation at the surface, convection makes it rise, adiabatic lapse rate makes it cool below the dewpoint. When the cloud forms it reflects 85% of the very energy source which creates clouds straight back out into space. So it has a really convenient negative feedback. If clouds as a net effect made the surface warmer, which would in turn evaporate even more water and make even more clouds, there’d be no such thing as clear sky!
Snow and ice doesn’t have a negative feedback to stop any run-away effect of increasing cold. It has a positive feedback. The colder it gets at the surface the more snow and ice form. This is the dangerous side of potential climate change. For most of the last several million years Washington, D.C. was under a mile of ice. I don’t think we can pump enough CO2 into the atmosphere to stop that from happening again although one might understandably and fervently wish it were so. A repeat of the Eocene Climate Optimum would be nice – earth green from pole to pole, average temperature 6-8C higher than today, CO2 level 2000ppm and persisting in that general warm regime for hundreds of millions of years. That’s like a golden ages for the biosphere although taken in whole over the last 500 million years its the rule not the exception. Conditions like that are what laid down fossil fuels in the first place. In comparison we’re in a biologically deprived stunted freezing world perched on the brink of a 100,000 year long glacial epic. We should be trying to defeat the ice age not help it along.
that limits how great the cloud cover can be for how long before it’s self-defeating. Snow and ice on the other hand have positive
R. Craigen says:
October 26, 2010 at 7:25 am
“What happens if we use the period 1940 to 1970 to determine forcing and sensitivity?”
Anthropogenic aerosols get blamed for temporarily overcoming the warming effect of CO2.
If that’s true then the easy solution to global warming would then be to stop filtering the aerosols from our emissions. The worst consequence (other than global cooling) is acid rain as I recall and that was very regional nearest the biggest sources. All we’d have to do is carefully distribute sulfate emissions to avoid regional acid rains and there you go. It would also lower the cost of industrial processes and transportation (filtering costs $$$) so it would have a positive economic impact.
I say go it for it. It’s plausible, fast acting, and worth a try since cost is less than nothing. I grew up in rural western New York 50 miles SSE from Bethlehem Steel which was supposed to be one of the worst places on earth for acid rain at the time and I didn’t notice a difference in any vegetation, wildlife, or agriculture after it largely shut down. The forest and farms and fields and river are all pretty much the same. Winters have been milder for sure which only lends more credence to the aerosol cooling hypothesis.
http://en.wikipedia.org/wiki/Bethlehem_Steel
*******
Willis says:
I decided to use the total Greenhouse Effect (as the ΔT) and then the energies involved. The total Greenhouse Effect is perhaps the least controversial aspect of the Global Warming debate. I will use the normally accepted value of the Greenhouse Effect as 30 °C.
*******
Willis, Dr Spencer says the total GHG effect is 60C, not 30C.
http://www.drroyspencer.com/2010/09/why-33-deg-c-for-the-earths-greenhouse-effect-is-misleading/#comments
This would make the fractional CO2 effect less (and more reasonable),but still too high IMO. Dr Spencer speculates that since water evaporation reduces the total GHG by about half, so increased evaporation reduces a given increase in forcing’s effect by 50%.
Not being a real expert, i.e. I wasn’t around then to do real measurements, I suspect that not only the underwater volcanism played a role in the recovery to non-snowball status. Volcanos around the PacRim as well as across Europe and Africa wouldn’t have necessarily been idle. I wonder what the weight of the ice did to the stresses on the plate boundaries? I can imagine that there were some interesting tremors, if you were a seismologist.
So much that we don’t know, or can’t know, but just try to deduce. Life is interesting if you’re really curious.
George E. Smith says:
October 25, 2010 at 3:46 pm
“By the way, I wish people would stop assigning significant albedo contribution to snow and ice cover (mostly in te polar regions) rather than to cloud cover which averages about 61% on earth (cloud cover, not albedo)”
—————————–
One has to also factor in the optical depth of the clouds (the actual amount of sunlight reflected back out) which averages only 28%. It gets darker under a cloud but it does not become pitch black.
So, clouds are only about 17 percentage points of the global Albedo of 29.8%. Land and Ocean Albedo is about 14 percentage points. During the ice ages, Land and Ocean Albedo may increase to about 17 percentage points so it does take alot of glacier and sea ice to move this number. But every percentage point is 3.4 Watts/m2 so every percentage point has a big impact on the climate.
Regarding Bill Illis says: October 26, 2010 at 10:00 am
Thanks for the post, now a question. So about 72% of the energy continues through the cloud cover to reach the surface. How has its wave length been affected? Is any more of it long wave?
Thanks
racookpe1978 says:
The past three year’s global recession is directly traceable to the democrat’s and liberal’s CO2 programs and energy policies.
I thought we were trying to have a grown-up discussion here about the science. That doesn’t seem possible on this site.
Regarding Tim Folkerts says:
October 25, 2010 at 5:15 pm
Ouote “I can’t see any way to escape the logic that more water vapor (and more GHG’s in general) should and do have a net affect of warming the planet.”
Tim, if I am following this correctly it is the residence time of the full spectrum of TSI in the earth system that matters. Your statement sounds true to me in regard to the atmosphere, but twenty percent less energy goes into the oceans due to the increase in water vapor. The short term effect is to heat the atmosphere, the long term is to cool the oceans.
I don’t have any dispute with your numbers Bill; different people give different values for Albedo (total) and I don’t think that is a big problem since I don’t think it can be measured with great precision anyway.
And of course although “cloud cover” may be described as 61% or some other number; that doesn’t mean that all of that is highly reflective. I have now several hundred photos of cloud tops taken from 36,000 ft on a daylight round trip to Oahu; from which I expect to be able to extract some range of variation in cloud brightness; bearing in mind the pixel numbers will likely be gerrymandered by my camera “stupidity”.
I think the answer to David’s question is that the sunlight will likely undergo some spectral selectivity in navigating through the cloud; but other than that is not significantly altered. However the portion of the sunlight that gets absorbed in water or ice crystals or water vapor in the cloud; will of course become thermalized and result in downward LWIR emission. But that should always be kept separate from albedo considerations which are always sunlight spectra, wiht as I said the possibility of some spectral selectivity.
And although the net reflectance may be 28% some deeper clouds will have a considerably higher reflectance, and some a lot less. I was quite surprised by the range of visible brightness of different clouds, in virtually the same position and sunlight; based on cloud morphology.
“”” Steve Metzler says:
October 26, 2010 at 10:47 am
racookpe1978 says:
The past three year’s global recession is directly traceable to the democrat’s and liberal’s CO2 programs and energy policies.
I thought we were trying to have a grown-up discussion here about the science. That doesn’t seem possible on this site. “””
Try over at c-r for a real adult debate. It is so easy to just ignore posts; there’s so many to read. That’s why they have libraries; people like to read different books too.
Tim, here is another look att he same comment:
Much of CAGW theory is based on the “T” factor of energy in the atmosphere?
I see it basically like a freeway. If the incoming traffic (TSI) is constant, but the speed of certain cars reduced (residence time increased) by the cops (GHG) the total traffic, (energy/ temperature) increases.
In the above the atmosphere is the freeway, and the TSI is incoming traffic. GHG are the cops that slow down certain red sports cars, (LW radiation) thus increasing the energy or density of traffic on the freeway. However, our earth has more then just freeways. We have many side streets that reduce the speed (residence time of incoming radiation) of traffic more then anything on the freeways. (atmosphere),
These slower streets are the land and Ocean, and what happens here effects the residence time (speed) of vehicles more then what happens on the freeways. A photon of SW radiation entering and penetrating the ocean slows down dramatically compared to the freeway of the atmosphere. So the total traffic flow (earths energy budget) depends on the time spent on all streets, not just the freeways, or atmosphere.
If water vapor and clouds increases in the atmosphere, (more cops enter the freeways) less traffic enters the side streets, the oceans, and even though freeway traffic increases due to more freeway cops, side street traffic is more sparse (cooling) and TOTAL TIME in the traffic system is reduced even though the freeway traffic is temporarily increased.
“””” Steve Metzler says:
October 26, 2010 at 4:57 am
The author doesn’t even understand the first thing about what a doubling of CO2 actually means. Tom Kehr says in the original post:
So all other factors in the Earth’s climate account for 14% of the GHE and CO2 by itself accounts for the other 86%. This can also be compared to the number of CO2 doublings that take place from 1 ppm to 390 ppm. That is roughly 8.6 CO2 doublings (1,2,4,8,16,32,64,128,256,390 ppm). Using 8.6 doublings from 1 ppm gives 25.8 °C. So their model is coherent, but saying that CO2 causes 86% of the GHE is extremely incorrect.
To say that CO2 ‘doubled’ when it went from 1ppm to 2ppm is a fine demonstration of his complete ignorance on the subject. When scientists refer to a doubling of CO2, they mean from the pre-industrial (ca. 1750) value of 280ppm to 560ppm (which, if we keep going the way we are now regarding the use of fossil fuels, will happen sometime around 2050). Anything below that value of 280ppm is essentially meaningless to us going forward. In fact, if you look at the CO2 levels derived from Vostok ice cores, the CO2 level has never been below 180ppm for the past 400,000 years, even during ice ages. “””””
Well how about a little consistency. either the global mean surface Temperature is a linear function of the log of the CO2 abundance, or it isn’t. Climatism 101 says it is; and if we accept that, then John’s numbers are correct.
Your post is the very first time I have ever seen anybody refer to Climate Sensitivity as the rise in mean global surface temperature for an increase in CO2 from 280 ppm to 560 ppm. It is almost universal to refer to the Temperature rise per doubling; and that specifies a log function; which isn’t some arbitrary non linearity.
We get these weasel words about , for very low values the change is linear with CO2, and then it gets harder to absorb more so it becomes logarithmic. It may become non-linear; but not logarithmic. Phil adds that at even higher concentrations it goes as square root of CO2 (I hope I’m not misstating what Phil has said.). The point is that in order to establish or solidify any sort of cause and effect relationship it is mandatory to be able to home in on a plausible mathematical relationship; that is traceable to basic physical laws (eventually)
Steve Metzler says:
October 26, 2010 at 10:47 am (Edit)
racookpe1978 says:
The past three year’s global recession is directly traceable to the democrat’s and liberal’s CO2 programs and energy policies.
I thought we were trying to have a grown-up discussion here about the science. That doesn’t seem possible on this site.
The CAGW “science” is being (deliberately) used by the “scientists” to generate their power, their funding, their influence, and their recognition. It is being used for their “feel good” sense of “doing something for society/Gaia/the environment.
The so-called CAGW “science” is being used by the liberal and extremist politicians for THEIR power, their control of the world’s power, its future, and its economy. Same for the universities and the national labs – the funding and the sense of power is overwhelming.
Pelosi’s restructuring of the oil exploration rules, of the funding for EPA/NOAA/NASA/GISS/ERDC etc, of her control of the energy and gas committees, of the tax and environmental legislation that was passed between her and the liberal-controlled Senate in 2007 and 2008 – in the specific name of fighting CAGW and funding alternate energy schemes – led to the destruction of the automobile, airline, housing, farming, and travel industries because they depend heavily on energy prices. Manufacturing, shipping, and heavy development immediately followed those losses into shutdown mode, and the recession was off into its course. The financial problems of Sept and Oct 2008 – just before the election of 2008 – came FROM the previous problems in the core industries. Those problems in finance, housing, securities, and insurance came BECAUSE the foundations of the economy (energy and production) were destroyed in the name of CAGW tactics.
“Science” ? The so-called CAGW “science” is being used just as it is intended to be used.