Guest post by Ira Glickstein PhD.
We had joy, we had fun, we had Seasons of the Sun.
But the mountains we climbed were but whimsies of our minds.
That song (apologies to Terry Jacks) could well be the theme for the official climate Team as they hike to the airy peak of Mt. Hansen on the supposed 0.8ºC warming since 1880, only to look out at the bleak prospect, for them, of level ground, and the possibility of some cooling over the coming decades.
This is the third of my Tale of the Global Warming Tiger series where I allocate the supposed 0.8ºC warming since 1880 to: (1) Data Bias, (2) Natural Cycles, the subject of this posting, and (3) AGW, which will be the subject of a subsequent posting. Click Tiger’s Tale and Tail :^) to see my allocation and read the original story.
NATURAL PROCESSES AND CYCLES
This posting is about how natural processes and cycles have dominated the global warming experienced since 1880. The base chart for the above graphic is the NASA GISS Global Land-Ocean Temperature Index that indicates the official climate Team estimate of about 0.8ºC net warming, the majority of which they allocate to human activities. In contrast, according to my annotations, the actual net warming is closer to 0.5ºC (0.8ºC – 0.3ºC Data Bias), and most of that, 0.4ºC, is due to natural cycles and processes over which humans have no control or effect.
The violet curve in the graphic is my estimate of the effect of natural cycles from 1880 to the present. There are many natural processes that affect the surface temperature of the Earth, but nearly all of them gain their energy from the Sun which is why I call them Normal Seasons of the Sun. In the following three sections, they are divided into three groups, according to their time scales and effects.
GRADUAL PROCESSES AND CYCLES LESS IMPORTANT ON HUMAN TIME SCALES
Biological life is thought to have existed on Earth for about 3.5 billion years. Over that enormous time period, natural processes and cycles have affected the evolution of life. Absent those processes, we would not be here, or at least not in our current condition. However, some of these processes and cycles operate ponderously slowly, to the point they are barely noticed on the time scale of an individual human life or even on the time scale of ten lives. Therefore, they are of virtually no concern:
(a) Brightening Sun The Sun is about 4.5 billion years old, and about halfway through what is called the main sequence evolution for a star of its type. It has been getting brighter, but very slowly and nearly imperceptibly. In about 5 billion years, the Sun will become a Red Giant, and life as we know it on Earth will no longer be possible. However, the rate of brightening is so small that we may ignore it.
(b) Milankovitch Cycles. The Earth’s orbit around the Sun is affected by slow, cyclic variations in eccentricity (100,000 years), axial tilt (41,000 years), and precesssion (21,000 years). Changes in the Earth’s orbit do not affect the quantity of average yearly solar radiation, but the distribution between equatorial regions and polar regions is affected. This may be the cause of the approximately 100,000 year cycle of ice age glaciations. However, the contribution of these effects over a period as short as that from 1880 to the present is so small we may ignore it.
(c) Heat from Earth’s Core. About 0.01% of the energy responsible for heating the surface of the Earth is due to energy from the decay of radioactive materials in the Earth’s core. This source has a half life measured in billions of years. This is such a tiny fraction of the Earth’s heat budget that we may ignore it.
PROCESSES AND CYCLES OF IMPORTANCE ON HUMAN TIME SCALES
(d) Normal Seasons of the Sun. The nominal 11-year Solar Cycles, during which Sunspot counts vary from low numbers to a peak and then down again, may be as short as 9 years or as long as 14. Magnetic polarity changes for every pair of cycles, so there is an 18 to 28 year magnetic cycle. Often there are series of three or more cycles, spanning periods of 30 to 150 or more years where solar activity may be very low (below 50 spots per month) and series of similar lengths where activity may be very high (above 100 spots per month).
Low Sunspot series are historically associated with decades of unusually cold climate and vice-versa for high Sunspot series. Total Solar Irradiation (TSI) does not change much during a single Sunspot cycle, but, over a series of high (or low) cycles, it may change enough to result in an increase (or decrease) of 0.1ºC. This TSI effect of Solar Cycles accounts for about a quarter of the of 0.4ºC I have allocated for natural cycles.
(e) Henrick Svensmark’s Global Cosmic Ray (GCR) Theory. GCRs have a positive role in the formation of clouds. Low-lying daytime clouds tend to cool the surface of the Earth. Therefore, all else being equal, the more GCRs, the more clouds, and the cooler the surface of the Earth. Increased solar magnetic activity, which coincides with higher Sunspot numbers, may divert some portion of GCRs from reaching the Earth, thereby reducing cloud formation and thus lessening their cooling effects.
Via this mechanism, a series of high Sunspot cycles may indirectly cause surface temperatures to rise, and a series of low cycles may cause them to fall, which is consistent with the historical record. Svensmark’s theory, if correct, could account for some of the 0.4ºC I have allocated to natural cycles and processes.
(f) Multi-Decadal Ocean Oscillations. There are a number of ocean oscillations, with periods of from less than a decade to multiple decades, that affect sea surface temperatures and therefore have climate impacts worldwide. These include the Pacific Decadal Oscillation (PDO), the El-Niño Southern Oscillation (ENSO), North Atlantic Oscillation (NAO), and others. The ENSO, for example, has a warm phase, called El Niño, Spanish for “the boy”, and a cool phase, called La Niña, “the girl”. The El Niño that started in 1998 caused global warming of 0.1ºC to 0.4ºC for a couple years.
While the net effect of any cycle on temperature anomalies is zero, they have significant effects during their high and low durations. Given the existence of several, somewhat independent ocean oscillations, their high and low times may tend to reinforce or cancel each other out, and that may explain multi-decadal episodes of positive and negative anomalies. There may be some correlation of these cycles with solar activity, which is, of course, the main source of their energy. Thus, ocean cycles could account for some of the 0.4ºC I have allocated to natural cycles and processes.
POSITIVE AND NEGATIVE FEEDBACKS OF IMPORTANCE ON HUMAN TIME SCALES
(g) ATMOSPHERIC GASES (net positive feedback). Long-wave radiation from the Earth extends from about 4 to 25 microns, with maximum energy around 10 microns. See the absorption spectrum for “greenhouse” gases. Note that the absorption spectra for water vapor (H2O) in the range of interest extends from about 5 to 8 microns and from around 12 to 25 microns. Note also that the absorption spectra for other atmospheric gases, such as methane (CH4), carbon dioxide (CO2), nitrous oxide (NO2), and oxygen/ozone (O2/O3), partially overlap H2O such that the atmosphere absorbs (and re-emits) nearly 100% of 4 to 25 micron radiation, except for two nearly transparent windows in the 8 to 9 and 10 to 12 micron regions.
Nearly all the carbon gases in the atmosphere are from natural sources, mostly respiration and digestive gasses of living animals and the decay of dead plants and animals. (The small proportion of carbon gases due to human activity, mainly burning of previously sequestered coal, oil, and natural gas, will be discussed in a future topic here on WUWT. For the purposes of this posting, only natural carbon gases are considered.)
When an atmospheric gas absorbs longwave radiation in its spectrum, that radiative energy is re-emitted in a broader spectrum and in all directions, about half towards the Earth and the other half out towards space.
When atmospheric CO2 absorbs 4 to 5 micron radiation from the Earth, or CH4 absorbs 7 to 8 micron radiation, and that energy is re-emitted, some will fall into the nearly transparent windows and head out to space nearly unimpeded. About half of the remaining energy will be re-emitted back towards the Earth’s surface and will add to warming.
The same is true for H2O, NO2, O2, and O3. Thus, increases in any of these gases will tend to increase warming of the Earth, all else being equal. That means, should the surface of the Earth experience a temperature increase, due to natural solar effects or any other cause, and if that increases emission of carbon gases from equatorial and summer temperate oceans, and reduces absorption of carbon gases by the polar and the winter temperate oceans, that will consititute a positive feedback. The inverse is also true. Should surface temperatures decrease, and if this reduces the amount of CO2, CH4, or H2O gases in the atmosphere, that will reduce the “greenhouse” effect, and tend to further cool the surface. Thus carbon gases and water vapor represent a positive feedback to surface warming.
(h) CLOUDS (net negative feedback). Short-wave radiation from the Sun extends from about 0.2 microns (ultraviolet light) to 2 microns (near infrared light), with maximum energy around 0.5 microns (green light in the visible spectrum). Moderate warming of the surface has a net effect of increasing the extent of cloud cover. Daytime clouds reflect much of the short-wave radiation back out to space, which is a powerful negative feedback. However, both day- and nightime clouds also absorb long-wave radiation from the Earth and re-emit about half of it back down, further warming the surface, a positive feedback. There is disagreement over whether the net effect of clouds is warming or cooling. Most of the official climate Team models assume the net effect is positive, others, including me, assume it nets out as negative.
(i) SURFACE ICE (net positive feedback). Ice, having a high albedo (reflective quality of white or light-colored surfaces), reflects much of the short-wave radiation from the Sun back out to space, which has a cooling effect. Warming of the Earth’s surface may thin and ultimately melt the ice and expose the underlying sea water or land. Water and land are less reflective. Thus, warming that causes melting has a net positive feedback.
(j) THUNDERSTORMS, HURRICANES, ETC. (net negative feedback). These tend to mix the atmosphere and, since the surface is generally warmer than the lower air masses, storms and other disturbances of the atmosphere tend to be a cooling influence. Thunderstorms, in particular, tend to lift warmer air from the surface to higher elevations where the heat energy may more readily radiate out to space.
Thus, if warming of the surface causes more water vapor in the atmosphere, and if this causes more thunderstorms and hurricanes, or makes them more intense, they have a negative feedback effect.
(k) PRECIPITATION (net negative feedback). Water vapor in the atmosphere cools by radiation of its heat energy in all directions, including out to space. The vapor condenses, forming liquid (rain) and solid (snow) water precipitates. Since the radiating tends to take place high in the atmosphere, where the heat energy may more readily radiate out to space, this precipitation constitutes a net cooling effect. Rain and snow tend to be cooler than the surface, and that is also a net cooling effect. Thus, if warming of the surface causes more water vapor in the atmosphere, and if this causes more precipitation, that is a negative feedback effect.
(l) VOLCANIC ERUPTIONS. These spew hot gases, liquids, and solids from the bowels of the Earth onto the surface and into the atmosphere. In the short-term, this tends to heat the surface. However, the aerosols from the volcano, basically sulphur and other mineral compounds, are driven high into the air and tend to remain for years, which tends to reflect Sunlight back into space, which, in the longer-term, tends to cool the surface. The net effect is cooling. For example, the eruption at Mt. Pinatubo in 1991 cooled global temperatures 0.1ºC to 0.3ºC for a few years thereafter.
CONCLUSIONS AND REQUESTS
I believe I have hit on and briefly described all the major natural processes and cycles that affect average global temperatures. However, if readers have additional information or corrections to what I said about any of them, or if there are some I missed, I would appreciate detailed comments to improve my summary.
It seems to me that my estimate of 0.4ºC for Normal Seasons of the Sun is fully justified, but I am open to hearing the opinions of WUWT readers who may think I have over- (or under-) estimated this component of the supposed 0.8ºC rise in global temperatures since 1880.
In my first and second postings in this Tale of the Global Warming Tiger series, I asked for comments on my allocations: to: (1) Data Bias 0.3ºC, (2) Natural Cycles 0.4ºC, and (3) AGW 0.1ºC.
Quite a few readers were kind enough to comment, either expressing general agreement or offering their own estimates.
Some commenters claim that the actual Data Bias is larger than my estimate of 0.3ºC. Some think Data Bias may be responsible for the entire amount of the supposed 0.8ºC rise in global temperatures since 1880, meaning that net warming over that period is ZERO. I accept that Data Bias may be 50% more (or less) than my estimate, which would put it between 0.15ºC and 0.45ºC, but I doubt it could be as large as 0.8ºC.
Others commenters claim that AGW is ZERO. In other words, they believe that rising CO2 and land use changes due to human activities have no effect on temperatures or climate. They believe the lack of effect is due to the negative feedback from cloud albedo and other natural negative feedback processes. I agree clouds have a net negative feedback (most official models assume a net positive feedback) but I do not believe this cancels out all the effects of CO2 on the Earth’s surface absorption of Solar radiation nor of albedo changes due to land use. I accept that AGW may be 50% less (or more) than my estimate, which would put it between 0.05ºC and 0.2ºC, but I doubt it could be as large as 0.8ºC.
What do you think? I have been keeping a spreadsheet record of WUWT reader’s opinions, which I appreciate and value greatly, along with their screen names, and I plan to report the results later in this series.
This is what you may look forward to:
Some People Claim There’s a Human to Blame – Yes, human actions, mainly burning of fossil fuels and changes in land use, are responsible for some small amount of Global Warming.
Is the Global Warming Tiger a Pussy Cat? – If, as many of us expect, natural processes lead to stabilization of global temperatures over the coming decades, and perhaps a bit of cooling, we will realize the whole Global Warming uproar was like the boy who saw a pussy cat and cried tiger.
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Dr. Glickstein — now wait just a minute …. you say
“When atmospheric CO2 absorbs 4 to 5 micron radiation from the Earth, or CH4 absorbs 7 to 8 micron radiation, and that energy is re-emitted, some will fall into the nearly transparent windows and head out to space nearly unimpeded. About half of the remaining energy will be re-emitted back towards the Earth’s surface and will add to warming.”
That is not possible. That radiation you are speaking of just cooled the surface by the same amount when it radiated into the atmosphere and was absorbed. You must mean “the cooling of the surface was cancelled” by the same amount. Now that would be a true statement.
This is AGW proponents douuble speak, they forget or hide the fact the same radiation they are saying warms the surface just got through cooling the surface when it left. You can’t have it one sided, true physics will not left that occur.
Nice graph but we do not know what all the natural cycles are so this will be wrong possibly by a large margin. Remember both the Medieval and Roman warm periods were warmer than today and they were driven by natural cycles. This makes the guessed gap between natural and AGW warming on the graph just that- a total guess.
The latest research is showing a greater input from solar physics that was ever thought possible and according to Peter Taylor’s book Chill these were enough to cause what was considered to be the CO2 warming. This warming, based on a false premiss, assumes that CO2 levels have been level at 285ppmv. A simple internet search proves that this figure is total rubbish. The actual action of atmospheric CO2 levels varied by a considerable amount from this guessed figure of 285. Over 450ppmv was apparently the norm back in the 19th cent, as measured across Europe at the time. See:- Beck 2007 ‘180 Years of Atmospheric CO2 Gas Analysis by Chemical Methods. 25 pages of interesting research and an easy read.
Often there are series of three or more cycles, spanning periods of 30 to 150 or more years where solar activity may be very low Grand minima.
http://www.vukcevic.talktalk.net/MagAn.gif
Very nice summary of a number of other processes that have been willfully ignored by the AGW machine. And I would agree with the authors view that many of these may likely have been influential on the temperature record. However, the quantification is a strawman – which serves to make a good discussion – but without observational evidence and without falsifiable theory, the strawman is no better that the AGW story. As much as I also think it is ‘more likely’ and forms a much more well rounded story, care needs to be taken with presenting numbers like this.
Please replace above link with:
http://www.vukcevic.talktalk.net/MagAn.htm
[Perhaps you might like to do that]
What, imho, seems most relevant is the compounded uncertainty. Very little of the information leading to even the range of temperatures attributed to a specific cause is “iffy” along with what one might call compounded gradients. Suppose, for example, you measure a discrete area and 100% resolve accuracy of temperature impact for that one area. You have a specific gradient, high and low, for a specific time. There’s little, if any, serious analysis of how one contributing factor’s gradient interacts with another other than a series of assumptions and all based upon further assumptions based upon even further assumptions. Of the lot, only Svensmark’s theory is specific enough to be provable, in the human time scale, and, even then, it’s impact will be debated until all these gradients are resolved. In short, unlikely in my personal human time scale.
Dear Ira. Excellent summation which could double as an executive summary. As long as you have no objection, I’ll be sending this to my MP for his consideration.
Ira
Interesting in terms of the numbers but there are far too many assumptions and not enough proofs.
Als, correct me if I’m wrong, but you say ‘max energy at 0.5µ (green light) but is that true? E = h . mu in joules where mu is wavelength.
“(i) SURFACE ICE (net positive feedback). Ice, having a high albedo (reflective quality of white or light-colored surfaces), reflects much of the short-wave radiation from the Sun back out to space, which has a cooling effect. Warming of the Earth’s surface may thin and ultimately melt the ice and expose the underlying sea water or land. Water and land are less reflective. Thus, warming that causes melting has a net positive feedback”
Open water loses more heat than ice-covered water. It’s not as simple as albedo, especially since a lot of the places where ice exists are at latitudes that don’t receive sunlight when ice is at its highest extent.
I don’t think negative feedback could cancel out a forcing entirely. That would require infinite negative feedback. For example, if a forcing changed a variable by 1 unit, then negative feedback of -1/9 would reduce the change by 0.1 of a unit to 0.9 of a unit, since -1/9 * 0.9 = 0.1 Negative feedback of 1 would reduce the change by 0.5 to 0.5, since -1 * 0.5 = 0.5 Negative feedback of -999,999 would reduce the feedback by 0.999999 to 0.000001, since -999,999 * 0.000001 = 0.999999.
Another way to think of it is that the feedback needs some of the original change to be left for the feedback to work on.
My guess is that negative feedback of -2 reduces the change in temperature to 1/3 of what it would be without feedback. So if doubling CO2 would raise the temperature by 1.2 Celsius, then that’s 0.4 degrees after negative feedback.
Ira,
Good presentation!
The Global Warming hype is all natural from Ice Age to Ice Age slow warming.
Climate science missed watching the precipitation and evaporation patterns as they are not temperature numbers.
So now the ocean currents have shifted the ocean heat and changed the weather on climate science.
Hi Ira!
I think you covered most of it, but you did forget a few.
1) There is also cooling caused by the gases in the atmosphere due to the re-radiation of sunshine 0-5 um coming from the sun e.g. see here:
http://www.iop.org/EJ/article/0004-637X/644/1/551/64090.web.pdf?request-id=76e1a830-4451-4c80-aa58-4728c1d646ec
they measured this radiation as it bounced back to earth from the moon. So this radiation was : sun-earth – moon /. Clearly, as it must have left earth it must have caused cooling. For the CO2, follow the green line in fig. 6, bottom. Note that it already starts at 1.2 um, then one peak at 1.4 um, then various peaks at 1.6 um and 3 big peaks at 2 um. You will find it back in fig 6 top.
2) There is also cooling caused by CO2 due to its participation in photo synthesis.
I noted that in the early mornings here, if you enter a forest, it is cool from the bottom up. You can feel that the trees and foliage drains energy from its surroundings. This is obviously also the reason why there is no forests growing at higher- altitudes and latitudes. So note that all the green you see, even that in the sea, extracts this energy from earth and without the CO2, this would not happen.
By not acknowledging this oversight of these two cooling factors, you would be making the same mistake as Svante Arrhenius and a whole herd of people who kept following his theories.
As for me, I think I have proven that the net effect of the cooling and warming of the carbon dioxide is probably close to zero, or possibly,
if I look at my own results in this report:
http://www.letterdash.com/HenryP/assessment-of-global-warming-and-global-warming-caused-by-greenhouse-forcings-in-pretoria-south-africa
it could even be that the net effect of more CO2 is (very, very) slight cooling.
Please remember you all that carbon dioxide is good for life. Pity global warming has stalled because that is not bad for more greenery and better crops either.
Sorry Ira,
may be you should also read what I wrote here,
http://www.letterdash.com/HenryP/more-carbon-dioxide-is-ok-ok
because it seems you are a bit confused about what causes radiative cooling and what causes radiative warming.
They talk about climate change as if it’s a bad thing.
Thank God for climate change.
Otherwise it would be really boring, decade in and decade out.
Excellent analysis, Ira. I think an AGW effect of 0.1C is probably too generous, but in any case it’s small enough to be of not much consequence, and that consequence would be primarily a positive one anyway. The issue of land use change is a bit of a red herring, because while there certainly are environmental effects to consider, whatever warming it causes would be primarily local, and its contribution to overall warming miniscule.
Ira: You wrote, “The El Niño that started in 1998 caused global warming of 0.1ºC to 0.4ºC for a couple years.”
The 1997/98 El Nino actually started in 1997 and it shifted global temperatures up for more than a couple of years.
A few more notes.
The North Atlantic SST-based dataset that best describes the impact of the natural variations in the North Atlantic on global temperatures is the Atlantic Multidecadal Oscillation (AMO). The North Atlantic Oscillation is a sea level pressure-based natural mode of variablility. Since Sea Level Pressure and Sea Surface Temperature are closely coupled, there are North Atlantic Oscillation datasets that are based on SST anomaly data at two different locations; in other words those datasets use SST data as proxies for sea level pressure.
The PDO, as calculated and presented by JISAO, in and of itself, cannot be used directly as a proxy for the impact of the North Pacific (north of 20N) SST anomalies on global temperatures. In fact, the PDO data and the North Pacific SST anomalies are inversely related on decadal timescales:
http://bobtisdale.blogspot.com/2010/09/inverse-relationship-between-pdo-and.html
For those new to natural sea surface temperature variations, the following series of posts are introductions to the El Nino-Southern Oscillation (ENSO):
http://bobtisdale.blogspot.com/2010/08/introduction-to-enso-amo-and-pdo-part-1.html
And the Atlantic Multidecadal Oscillation (AMO):
http://bobtisdale.blogspot.com/2010/08/introduction-to-enso-amo-and-pdo-part-2.html
And the Pacific Decadal Oscillation (PDO):
http://bobtisdale.blogspot.com/2010/09/introduction-to-enso-amo-and-pdo-part-3.html
I see climate change as genus.
It pushes the human race forward.
I guess I just see things different.
Think Different
Ira,
First I want to respond to the distribution of causes. I think data bias is about 0.1 C. I think natural cause is about 0.4 C. Thus human cause is about 0.3 C, of which farming, deforestation, and building (cities and roads) are about 0.1 C, and burning of fossil fuels and cement manufacturing (CO2 production) are about 0.2 C.
I like most of your write up, but have a few disagreements.
1) Biological and other causes are short term contributors that make the CO2 level go up and down fairly rapidly, but the average natural CO2 level is caused by volcanoes emitting and rock weathering and long term biological trapping. Ocean absorption or out gassing of CO2 becomes a major cause if the average temperature shifts.
2) Back radiation does not cause heating of the Earth. Back radiation is a consequence of the fact that greenhouse gases caused the Earth to be warmer than otherwise. The mechanism is that the absorption of much of the long wave radiation, and eventual transport of that energy by radiation is combined with the transport of energy from the ground by evaporation and convection. The energy eventually is transported to an altitude high enough to radiate to space. The altitude of radiation to space (it is actually spread out) is the average location where outgoing radiation to space matches the Earths absorbed solar radiation, and thus determines the effective temperature of the air at that average location. The convective mixing of the atmosphere cause an adiabatic lapse rate to form and be maintained, with a wet lapse rate when the water vapor condenses, and a dry lapse rate otherwise. The lapse rate, combined with the effective altitude of radiation to space, determine the lower atmosphere and ground temperature. For a couple of more complete descriptions, see:
http://climateclash.com/2010/11/25/g1-the-atmospheric-greenhouse-effect-and-its-effect-on-agw/
and also:
http://climateclash.com/2010/11/28/g2-greenhouse-gas-effect/
At absolute zero (0*K) nothing moves. Temperature does not reflect the total energy in a system as complex as our little issolated piece of the Universe (at least not the simple way ‘temperature’ is currently measured). Is it getting warmer or cooler? Nobody knows, we haven’t really measured the actual temperature once, much less twice to compare.
Ira, I think when the dust finally settles, man will have been responsible for much less than 0.01C.
“Climate change” is the main driver of evolution. It’s a natural process and the planet is programmed to do every bit of it “naturally”. If it wasn’t for “climate change” we would not be here.
I do not see where evaporation of water, which is temperature neutral as far as heating the atmosphere, the convection of warm humid air to altitude, the release of the heat of condensation, and the loss of this high altitude heat to space is included in this discussion. This also leads to the clouds that are discussed.
Convection has been estimated to account for 92% of energy transfer to altitude, while most people like to only talk about radiation fluxes. The water cycle is ignored nearly totally b the IPCC and handles the missing heat that Trenberth agonizes over in his e-mail.
Shouldn’t it be included?
Wow Ira it doesn’t seem you have a lot of support from the skeptic crowd. Most think you should massage your figures to give greenhouse gases a zero effect.
A couple of points from the AGW side.
Isn’t the total solar irradience at a minimum stage at the moment? Would that not mean that we should be cooling? http://www.usnews.com/science/articles/2011/01/19/improved-measurements-of-sun-to-advance-understanding-of-climate-change
You say nearly all the carbon in the atmosphere is from natural sources, and I do not disagree, but then isn’t all the natural CO2 emitted balanced by the Earths take up of the CO2 and that burning from fossil fuels pushes it into the area of imbalance causing slight warming, which causes evaporation of water vapor etc, which causes warming that causes etc. you can see where I am going with this.
Wayne Says: “That is not possible. That radiation you are speaking of just cooled the surface by the same amount when it radiated into the atmosphere and was absorbed. You must mean “the cooling of the surface was cancelled” by the same amount. Now that would be a true statement.”
This is a typical skeptic mistake and misunderstanding. Is it not true that Earth is not a closed system, the sun is adding heat all the time, if the heat coming in heats the surface and is radiated into the atmosphere but then half of it is bounced back then you have increased the heat in the system by the amount bounced back. Your understanding of ‘True Physics” is seriously flawed.
Other than that I do not see where the 0.4 of natural heating comes from? Most seems fairly balanced and if anything we should be cooling, so then why are we still heating up?
“Carl Chapman says:
January 23, 2011 at 4:55 am
I don’t think negative feedback could cancel out a forcing entirely. That would require infinite negative feedback. For example, if a forcing changed a variable by 1 unit, then negative feedback of -1/9 would reduce the change by 0.1 of a unit to 0.9 of a unit, since -1/9 * 0.9 = 0.1 Negative feedback of 1 would reduce the change by 0.5 to 0.5, since -1 * 0.5 = 0.5 Negative feedback of -999,999 would reduce the feedback by 0.999999 to 0.000001, since -999,999 * 0.000001 = 0.999999.
Another way to think of it is that the feedback needs some of the original change to be left for the feedback to work on.
My guess is that negative feedback of -2 reduces the change in temperature to 1/3 of what it would be without feedback. So if doubling CO2 would raise the temperature by 1.2 Celsius, then that’s 0.4 degrees after negative feedback.”
Reference the last paragraph; my recollection is that a lot of socalled “sceptics” including Dr Spencer and Prof. Lintzen are of the opinion that the net forcing of man made CO2 is probably in the region of 20-25% of the warming recorded since 1880 so that is not a mile away from the above estimate of 33%. Such individuals also seem to agree that gross temperature forcing of a doubling of CO2 is 1C which is also close to Chapman’s 1.2C.
I know that “weather is not climate”, however as a golfer residing in the Atlanta area, I want the warming back. December ’09 ran 3 – 4 degrees F below “normal” and December ’10 around 7 below. January 10 ran several degrees below “normal” and preliminary data for Jan. ’11 and the forecasts for the remainder indicate it will follow the same trend. This has cut into my golf by at least 50 percent and I find this very disconcerting. It really is too bad we couldn’t put enough CO2 into the atomosphere to change this trend even if we wanted to.