Last year I posted an analysis of satellite observations of the 2007-08 global cooling event, showing evidence that it was due to a natural increase in low cloud cover. Here I will look at the bigger picture of what how the satellite-observed variations in Earth’s radiative budget compare to that expected from increasing carbon dioxide. Is there something that we can say about the relative roles of nature versus humanity based upon the evidence?
What we will find is evidence consistent with natural cloud variations being the dominant source of climate variability since 2000.
CERES Observations of Global Energy Budget Changes
The following graph shows the variations in the Earth’s global-average radiative energy balance as measured by the CERES instrument on NASA’s Terra satellite. These are variations in the imbalance between absorbed sunlight and emitted infrared radiation, the most fundamental quantity associated with global warming or global cooling. Also show (in red) are theoretically calculated changes in radiative forcing from increasing carbon dioxide as measured at Mauna Loa.
Since there is some uncertainty in the absolute accuracy of the CERES measurements, where one puts the zero line is also somewhat uncertain. Therefore, it’s the variations since 2000 which are believed to be pretty accurate, and the exact dividing line between Earth gaining energy and Earth losing energy is uncertain. Significantly, all of the downward trend is in the reflected sunlight portion, not the infrared portion of the variations. We similarly can not reference where the zero line should be for the CO2 forcing, but the reasons for this are more complex and I will not address them here.
In order to compare the variations in the CO2 forcing (in red) to the satellite observations, we need to account for the fact that the satellite observes forcing and feedback intermingled together. So, let’s remove a couple of estimates of feedback from the satellite measurements to do a more direct comparison.
Inferred Forcing Assuming High Climate Sensitivity (IPCC View)
Conceptually, the variations in the Earth’s radiative imbalance are a mixture of forcing (e.g. increasing CO2; clouds causing temperature changes), and feedback (e.g. temperature changes causing cloud changes). We can estimate the forcing part by subtracting out the feedback part.
First, let’s assume that the IPCC is correct that climate sensitivity is pretty high. In the following chart I have subtracted out an estimate of the feedback portion of the CERES measurements based upon the IPCC 20-model average feedback parameter of 1.4 W m-2 K-1 times the satellite AMSU-measured tropospheric temperature variations
As can be seen, the long-term trend in the CERES measurements is much larger than can be accounted for by increasing carbon dioxide alone, which is presumably buried somewhere in the satellite-measured signal. In fact, the satellite observed trend is in the reflected sunlight portion, not the infrared as we would expect for increasing CO2 (not shown).
Inferred Forcing Assuming Low Climate Sensitivity (”Skeptical” View)
There has been some published evidence (our 2007 GRL paper, Lindzen & Choi’s 2009 paper) to suggest the climate system is quite insensitive. Based upon that evidence, if we assume a net feedback parameter of 6 W m-2 K-1 is operating during this period of time, then removing that feedback signal using AMSU channel 5 yields the following history of radiative forcing:
As can be seen, the relative size of the natural forcings become larger since more forcing is required to cause the same temperature changes when the feedback fighting it is strong. Remember, the NET feedback (including the direct increase in emitted IR) is always acting against the forcing…it is the restoring force for the climate system.
What this Might Mean for Global Warming
The main point I am making here is that, no matter whether you assume the climate system is sensitive or insensitive, our best satellite measurements suggest that the climate system is perfectly capable of causing internally-generated radiative forcing larger than the “external” forcing due to increasing atmospheric carbon dioxide concentrations. Low cloud variations are the most likely source of this internal radiative forcing. It should be remembered that the satellite data are actually measured, whereas the CO2 forcing (red lines in the above graphs) is so small that it can only be computed theoretically.
The satellite observed trend toward less energy loss (or, if you prefer, more energy gain) is interesting since there was no net warming observed during this time. How could this be? Well, the satellite observed trend must be due to forcing only since there was no warming or cooling trend during this period for feedback to act upon. And the lack of warming from this substantial trend in the forcing suggests an insensitive climate system.
If one additionally entertains the possibility that there is still considerable “warming still in the pipeline” left from increasing CO2, as NASA’s Jim Hansen claims, then the need for some natural cooling mechanism to offset and thus produce no net warming becomes even stronger. Either that, or the climate system is so insensitive to increasing CO2 that there is essentially no warming left in the pipeline to be realized. (The less sensitive the climate system, the faster it reaches equilibrium when forced with a radiative imbalance.)
Any way you look at it, the evidence for internally-forced climate change is pretty clear. Based upon this satellite evidence alone, I do not see how the IPCC can continue to ignore internally-forced variations in the climate system. The evidence for its existence is there for all to see, and in my opinion, the IPCC’s lack of diagnostic skill in this matter verges on scientific malpractice.
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Re: Invariant (15:40:10)
No need to imagine ocean cycles – cloud cycles are enough.
Pascvaks (15:38:41) :
Clouds are water vapor. Water vapor is a greenhouse gas. Ah… Ummmm…. And… no, ahhh…
depends… if you are in a north temperate zone, and it is summer clouds have a mostly cooling effect during the day because they block more sun energy than they keep in from the earth. But in the winter, the suns rays are very weak so cloud cover reflects more of the earth’s energy than it blocks from the sun.
trust me… when you wake up on the Canadian prairie in mid January to a bright blue sky without a cloud in sight… go back to bed because it’s 30 below. Pray for cloud.
Thank you Dr Spencer for this.
So proof at last that Kevin Trenberth is correct in his travesty email
the energy in is greater than the energy out = warming (not seen!!!)
Kevin Trenberth:
” The fact is that we can’t account for the lack of warming at the moment and it is a travesty that we can’t. The CERES data published in the August BAMS 09 supplement on 2008 shows there should be even more warming: but the data are surely wrong. Our observing system is inadequate.”
….
” We are not close to balancing the energy budget. The fact that we can not account for what is happening in the climate system makes any consideration of geoengineering quite hopeless as we will never be able to tell if it is successful or not! It is a travesty!”
Michael Mann wrote:
” Kevin, that’s an interesting point. As the plot from Gavin I sent shows, we can easily account for the observed surface cooling in terms of the natural variability seen in the CMIP3 ensemble (i.e. the observed cold dip falls well within it). So in that sense, we can “explain” it. But this raises the interesting question, is there something going on here w/ the energy & radiation budget which is inconsistent with the modes of internal variability that leads to similar temporary cooling periods within the models.
I’m not sure that this has been addressed–has it?”
Perhaps an apology to Trenberth is in order?
Spencer attribute the warming to clouds – this does not seem to agree with Svensmark where increased clouds = cooling.
Also clouds should be increasing – causing cooling – due to increased GCRs with quiet sun.
Would it be fair to say it is a travesty?
……….
GCR-climate connection – GCR’s increase low cloud cover via increased CCN production (via increased atmospheric ionization), which acts as a cooling effect on the climate.
IPCC
6.11.2.2 Cosmic rays and clouds
Svensmark and Friis-Christensen (1997) demonstrated a high degree of correlation between total cloud cover, from the ISCCP C2 data set, and cosmic ray flux between 1984 and 1991. Changes in the heliosphere arising from fluctuations in the Sun’s magnetic field mean that galactic cosmic rays (GCRs) are less able to reach the Earth when the Sun is more active so the cosmic ray flux is inversely related to solar activity.
Henry chance (10:32:39) :
“95% of the greenhouse efect is from clouds.
Everytine Joe Romm posts pictures of “dirty coal” plants, he includes “smoke stacks” These are not smoke stacks but steam releasing cooling towers. Evaporation and otjher sources of H2O creat humidity and clouds. More shade and less radiation of heat.”
I work at a Coal fired Power Plant and the stacks release water vapor and carbon dioxide. Coal is about 30% water and maybe 60% carbon with other impurties that generate ash. When the coal burns the water vapor goes out through the stack as does the carbon dioxide that is generated from the exothermic reaction of carbon and oxygen (the heat from this reaction boils water to steam to turn the turbine which then turns the generator to create the electricity). We also have a cooling tower but it only forms the clouds on cold days. In the summer the 7000 gallons per minute of evaporation go into the air as water vapor.
I Hesitate to jump in to this august group but, gentlemen, you are confusing me. According to Lindzen and Choi’s analysis of ERBE data, They seem to come to the exact opposite conclusion. The only way can accept the data is if Steve Sadlov is right and the y coordinates are reversed. I am wide open to be educated on the matter.
[quote TanGeng (10:37:40) :
Seems like some numbers that have a lot of uncertainty. I still don’t understand this conclusion. It seems to suggest that heat is being stored somewhere in some form that isn’t being measured by temperature, either lot of ice is melting, it’s being stored chemically in some form somewhere, or it’s someplace where we aren’t measuring. /quote]
Or that the satellites just don’t work as described and expected. There’s been differences between satellite measurements and ground measurements as high as 6 watts per meter squared.
So I will again ask if the raw data and computer source code used to come up with these satellite numbers is available to the public so the world can take a look at these processes for themselves.
“It should be remembered that the satellite data are actually measured, whereas the CO2 forcing (red lines in the above graphs) is so small that it can only be computed theoretically.”
On RealClimate, I posted an idea that might get a real measurement of the contribution of CO2 to warming but no one responded to the post. I guess I will try here. One should be able to get an actual measurement of adibatic cooling of a mixture of just oxgen and nitrogen. The current rate is about 10 degrees C per 1000 feet.
My idea is that once you get a real measurement of the adibatic cooling of air with no carbon dioxide. Then you can directly measure the actual adiabtic cooling of dry air with a known concentration of carbon dioxide. Since the carbon dixoide is absorbing energy from the ground (via Infrared emission) as the air rises, the warming of this absorbed energy should lower the adibatic cooling rate. It should end up less than 10 degrees per 1000 feet. The differenc between the experiment tested adibatic cooling of just oxygen/nitrogen and with the carbon dioxide added should give a real amount of energy carbon dioxide absorbs. Thanks to any who might answer this.
“Last year I posted an analysis of satellite observations of the 2007-08 global cooling event, showing evidence that it was due to a natural increase in low cloud cover”
So from the chart the Earth has been gaining energy for 8 years, especially from 2007 to 2008, despite increasing cloud cover that allows less energy to reach the surface.
“Significantly, all of the downward trend is in the reflected sunlight portion, not the infrared portion of the variations.”
More energy is being reflected, thus less is being absorbed, IR is constant. Forgive me, but shouldn’t this mean we are cooling (losing energy)? I mean, we are cooling if you go by the thermometer, it’s colder. I live on an Island thats usually 65-75 deg F this time of year and it’s 50, and there is no indoor heating. I know thats just weather, but….I just don’t see where the energy gained is going, the sea ice is recovering from it’s melting which was due mainly to ocean currents and wind patterns.
Don’t really get it, maybe I will reread it and his previous article and see what I missed.
tfp (16:14:03) :
Maybe you need to go back and read what Dr. Spencer referenced in his GRL paper and the first sentence of this article.
Low level Clouds=COOLING
Lack of low level Clouds=WARMING
Not
more low level clouds=Warming
Spencer agrees with Svenmark more clouds, more cooling
Lack of reading comprehension is a travesty.
Also Dr. Spencer has another presentation of this on his website:
http://www.drroyspencer.com/2010/01/a-demonstration-that-global-warming-predictions-are-based-more-on-faith-than-on-science/
pft (16:46:47) :
As I read it there’s less reflected sunlight (trend) which means fewer, not more, clouds. There are ups and downs, of course. And you can detect the 2007/2008 La Nina where the reflected sunlight went up (more clouds).
Looks to me like el Nino/la Nina dominate not only over the itsy bitsy bikini-clad CO2 but the Svensmaark effect as well.
As for the ‘lost’ heat, I think what lgl (14:08:22) said makes sense:
“If the conditions have changed from mostly heating the northern hemisphere to mostly heating the southern the situation will be exactly that because it takes much more energy to heat all that ocean down there.”
Henry chance (14:16:46) :
Joe Romm has just announced this is an anti-science blog
That is quite possibly an overblown claim, but there is a large amount of pseudo-science being peddled.
Am I the only one who can see my posts?
What is so hard to understand about the Moon and Earth sharing a dynamic interaction?
Have you all bought into the idea that the weather is a product of the surface conditions alone?
Then why would you believe the Sun had anything to do with it?
Oh yeah I mentioned the Moon!
“”” Pascvaks (15:38:41) :
Clouds are water vapor. Water vapor is a greenhouse gas. Ah… Ummmm…. And… no, ahhh…
Oh forget it. “””
Clouds may be a lot of things, including volcanic ash or sand or dust; but the one thing they most certainly are NOT is WATER VAPOR.
Water vapor is pretty much quite transparent to visible light, until you get to about 750-760 nm wavelength which is a very deep red; and a whole lot of people can’t see 760 nm red; specially old folks like me.
Water clouds, consist of water droplets or ice crystals, both of which scatter visible light; which is why you can see them.
The big thing to remember about clouds is that AT NIGHT they keep the surface warmer than it would be without them – ever had a frost on a cloudy night? During the DAY they reflect sunlight & keep the surface cooler than it would be in direct sunlight. This tends to bring the maximum & minimum temperatures closer together. Water vapour in the atmosphere does exactly the same thing, even without clouds. Look at the daily temperature range of a place on the coast compared to a point 100km inland – there is much less variation at the coast.
interesting. But would the formation of water clouds not be closely related to the amount of water vapor available to form the droplets and crystals?
As I remember from an atmospheric physics course, the stratosphere is stable (temperature increases with altitude) and therefore no convection like you get in the troposphere. My question is how does convection and redistribution of energy affect the time constant for the earth atmospheric engine? Presumably it takes a while for the engine to respond to a radiative input – just like a capacitor/resistor circuit – you get a delayed response.
How do we know that comparing the radiative balance is meaningful in terms of a system that might be capable of storing energy for decades or centuries and, in which case, what makes Dr Spencer able to make short term suppositions ( cloud cover) from changes in the radiative balance?
boballab (16:49:58) :
Last year I posted an analysis of satellite observations of the 2007-08 global cooling event, showing evidence that it was due to a natural increase in low cloud cover.
Low level Clouds=COOLING
Lack of low level Clouds=WARMING
Not
more low level clouds=Warming
Spencer agrees with Svenmark more clouds, more cooling
Low solar activity = high gcrs
high gcr=more low cloud=cooling = svensmark
as solar minimum was approached (=high gcrs=cooling=svensmark) the plots above show earth gaining excess energy.
I do not, I admit, understand how more energy = cooling
The plots show CO2 line doing the correct thing more co2=earth gaining excess energy so the plots are named correctly.
To me svensmark does not equal spencer
but trenberth = honest:
The fact is that we can’t account for the lack of warming at the moment and it is a travesty that we can’t. The CERES data published in the August BAMS 09 supplement on 2008 shows there should be even more warming: but the data are surely wrong. Our observing system is inadequate”
svensmark says -ve
spencer says +ve
trenberth says our observing system is inadequate.
Who is being honest here?
I’ve always thought that modeling against an RLC circuit per jeremy made sense. As I understand it, IPCC is claiming 3.7 watts/m2 from CO2 doubling, but the rise so far is only 38%. So for easy figuring, call it 1 watt to date. As I also understand, most heat storage is in the oceans, so lets put aside the atmosphere and the land mass and just heat up the ocean. Here’s the math (I think)
It takes 4 watts to heat up 1 cc of water 1 degree in 1 second. A square meter is 100 cm by 100 cm, so 10,000 cm2. So we need 40,000 seconds to heat 1 square meter to a depth of 1 cm. Lest the numbers get too large fast, that’s 11 hours. To get to 1 meter we would need 1100 hours, or around 46 days. To get to 100 meters, would take 12 years to transfer enough energy to make a 1 degree rise happen. 300 meters would take 36 years.
BUT – that assumes the capacitor doesn’t leak. Since a warming body increases the amount of energy it radiates back at its surroundings, it does in fact leak. My math skills have just been exhausted, but yeah, there should be serious latency between an energy increase and final temp.
boballab (14:55:24) :
Thank you for the reply. I wasn’t aware that Dr Pielke, Sr had problems with the concept of ‘global’ temperatures. And the Imperial Valley example you provided reminded me of something closer to home… my former home.
I am originally from the Kurdish South Eastern region of Turkey. I know that from 1970s onward the Turkish government began to implement a series of major dam construction projects on the Euphrates and the Tigris rivers for hydroelectricity generation as well as irrigation. The project is very controversial for many reasons and is still not finished. But in the last thirty years the geography has altered substantially and there are no many huge reservoirs that weren’t there thirty years ago. Several years back when I heard someone mentioning how the winters had become milder over several decades, I automatically attributed the reason to global warming. It is now more reasonable to assume that the winters had become milder simply because of the vast nearby water reservoirs. Similarly, most of the draught witnessed downstream -in Syria and Iraq- is more likely because less water is available to those places for irrigation and other purposes.
So one may easily conclude that the change in weather patterns (climate?) around and across the length of the Euphrates and Tigris has more to do with those dams than global warming. I haven’t read any report regarding the climatic impacts of the projects in the region. It would make an interesting case study, I think.
The important missing piece to this puzzle is the ability to accurately measure low level cloud cover.
If we go by the ISCCP who appear to be part of “the Team” they are telling us low level cloud has been on the decrease for the past decade. Perhaps this is another area of ClimateGate that needs to be investigated?
One explanation of the lack of current warming is the pipeline. Perhaps these guys that propose the pipeline should come up with the pipeline and how it can hold surplus energy and then some how miraculously scorch the earth in the future.
Sounds like trying to prove a negative to me.
Leif Svalgaard (17:26:56) :
Henry chance (14:16:46) :
Joe Romm has just announced this is an anti-science blog
That is quite possibly an overblown claim, but there is a large amount of pseudo-science being peddled.
Leif, broadly characterizing people wins you no points. Maybe you could be a little more charitable with your thoughts?
I am lost:
“If one additionally entertains the possibility that there is still considerable “warming still in the pipeline” left from increasing CO2, as NASA’s Jim Hansen claims, then the need for some natural cooling mechanism to offset and thus produce no net warming becomes even stronger.”
I can think of several possibilities. Assuming the satellite data is correct, energy stored in the oceans, increased vegetation mass or melting ice, for example, could reduce warming for a period of time. None of these natural “cooling mechanisms” however, could be effective indefinitely. What did I miss as I don’t seem to come to the same conclusion as Roy Spencer?
TerryBixler (10:35:51) :
Only a change in politics will change the position an AGW.
Which could start next Tuesday in Massachusetts.