By Dr. Roger Pielke Sr.
Andy Lacis has posted two guest contributions on my weblog;
Guest Post “CO2: The Thermostat That Controls Earth’s Temperature” By Andy Lacis
Further Comment By Andy Lacis On CO2 As A Climate Thermostat
I very much appreciate this collegial interaction.
Today, I want to comment on his conclusions.
First, I agree with Andy’s conclusion that if CO2 were removed from the Earth’s atmosphere, the climate system would rapidly cool. I also concur that CO2 is a first order climate forcing and is a non-condensing greenhouse gas forcing.
The more interesting question, however, is how this applies both to how the Earth’s climate system actually evolved, and how incremental increases in CO2 above what was present in pre-industral times alter the climate.
With respect to the early Earth atmosphere, CO2 was emitted from volcanic eruptions but so was water vapor. The two acted together to warm the climate. Indeed, this is one explanation proposed to explain the warm, wet period in the earlier atmosphere of Mars and Venus. While, the model experiment presented by Andy and colleagues is quite interesting, it does not reflect the real climate system.
The second issue is, of course, directly relevant to our future climate. As I posted in
we have examined the effect of incremental increases in CO2 (and water vapor) as described in detail in
Relative Roles of CO2 and Water Vapor in Radiative Forcing
Further Analysis Of Radiative Forcing By Norm Woods
In regards to the effect of an incremental effect on radiative flux of an increase in the atmospheric concentration of CO2, there is an informative figure at Watts Up With That in a post by David Archibald titled The Logarithmic Effect of Carbon Dioxide. The figure is from 2006 by Willis Eschenbach which was posted on Climate Audit.
What is of importance to our future climate is the added downwelling radiative fluxes as given by the green and black lines. The Lacis and colleagues study examined the effect of the radiative forcing from red line.
The issue with respect to our future climate is how will it be altered in response to these incremental increases, part of which (particularly in the humid parts of the world) overlaps with water vapor absorption).
In terms of how environmentally and societally important resources are altered, as I have often posted on (e.g. see), in terms of climate, this involves how droughts, floods, tropical cyclones, heat waves, etc are altered. This means the focus should be on alterations in regional ocean and atmospheric circulations, mesoscale weather patterns, and so forth rather than on trends in the global average surface temperatures. The addition of CO2 is one factor (both radiatively and biogeochemically) but is not the single ”control” of these climate metrics.
The equilibrium temperature of Earth is just one of these metrics, and, indeed is not adequate to explain how regional and local climate could change. In fact, even with respect to global warming and cooling, the use of ocean heat content is a much more robust way to diagnose these climate system heat changes than a global average surface temperature trend, as discussed most recently in
Pielke Sr., R.A., 2008: A broader view of the role of humans in the climate system. Physics Today, 61, Vol. 11, 54-55.
Andy’s posts (and paper) do clearly show that
“ there is a clear demonstration that without the radiative forcing provided by the non-condensing GHGs, the terrestrial greenhouse effect collapses because there is no structural temperature support to restrain the current climate water vapor from condensing and precipitating.”
However, there needs to be a recognition that the human influence on the climate system, including global warming and cooling, involves much more than the non-condensing greenhouse gases, and that the role of natural climate forcings and variability remain incompletely understood. We have discussed this in our paper
Pielke Sr., R., K. Beven, G. Brasseur, J. Calvert, M. Chahine, R. Dickerson, D. Entekhabi, E. Foufoula-Georgiou, H. Gupta, V. Gupta, W. Krajewski, E. Philip Krider, W. K.M. Lau, J. McDonnell, W. Rossow, J. Schaake, J. Smith, S. Sorooshian, and E. Wood, 2009: Climate change: The need to consider human forcings besides greenhouse gases. Eos, Vol. 90, No. 45, 10 November 2009, 413. Copyright (2009) American Geophysical Union.
I invite Andy to discuss where he agrees, and where he disagrees, with our conclusions and recommendations in the above paper.
“where Gerard’s paper shows a remarkable correlation between 65 deg north summer insolation & global ice-volume changes. Right there is earth’s “thermostat” direct from empirical data.”
Nah. Think of it at that scale like the cooling system in water-cooled automobile engine. The poles are the radiators. Water is circulated between engine and radiator by a pump in a car where the pump’s power is a small portion taken from engine. In the earth’s case the sun is the engine and most of its energy is transferred by absorption in the tropical oceans. The pump in this case is convective and, like the car, is driven by a portion of the power from the sun.
That’s pretty basic physics but it’s a good starting point to understanding how excess heat from the tropics is radiated out at the poles. Greatly complicating this over geologic timeframes is continental drift. When continents drift over poles it must greatly reduce the efficiency of the radiator because it blocks ocean currents from reaching the sweet spot for radiative performance where insolation is the weakest and water vapor is almost absent due to extreme cold. That’s why the south pole is much colder than the north – it’s a less efficient radiator.
Additionally sea ice cover will impede the performance of the radiator. Ice is a pretty good insulator so the warm water coming from the engine can’t radiate nearly as well. As the north polar ice diminishes the radiator becomes increasingly better at radiating. Everything appears to be working just as it should. The so-called “missing heat” is leaving the system through improved performance of the cooling system.
Bill Illis says:
November 13, 2010 at 9:57 am
My sediments exactly. Position of the continents critically changes the performance of the cooling system. Right now we’ve got a blocked up radiator at the south pole and and water flow restrictions at the north pole. When the radiators get blocked if everything else remains equal the poles will get colder and the tropics get warmer just as you’d expect when your car’s cooling system becomes impaired.
Angle of inclination will also have a potential effect because that causes the sweet spot for radiative performance to drift around which effectively moves the sweet spot in relation to the continents which drift much slower than the axis of inclination.
@jim D says:
November 13, 2010 at 10:13 am
Ulric Lyons says:
November 13, 2010 at 9:46 am
“And at c.450-438 million yrs ago ?”
There are natural processes that lead to a slow decline in CO2 (maybe 5-10 ppm per million years). These gradual declines are punctuated by rapid increases that are harder to explain (except the recent ones).
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But they are going in opposite directions, twice;
http://ff.org/centers/csspp/library/co2weekly/2005-08-18/dioxide_files/image002.gif
Ulric Lyons:
November 13, 2010 at 11:31 am
Do you rule out volcanic activity and meteor strikes as possible causes for cooling?
Anyway, I prefer this temperature plot which doesn’t have the crazy dips, rises and flat parts.
http://en.wikipedia.org/wiki/File:All_palaeotemps.png
Re: tokyoboy
Thank you very much for sharing this link:
http://www.data.kishou.go.jp/shindan/a_1/sl_trend/sl_trend_graph.png
Please also provide links to the data, related articles/materials, etc. – thank you.
Exercise for those interested:
Compare with:
1) AIR (All-India Rainfall)
2) Nutation in obliquity residuals.
3) LNC (lunar nodal cycle).
4) solar cycle acceleration.
Are EOP (Earth orientation parameters) not a part of standard climate science schooling? Perhaps therein lies one of the more fundamental problems. What is the value of a model that cannot reproduce EOP?
In general there’s too much focus on temperature without (sufficiently) mentioning pressure, volume, spatiotemporal heterogeneity (e.g. lapse rate variations), & tides [both gravitational & thermal].
These authors took a few wrong turns and haven’t finished what they’ve started, but the paper might help modelers considering upgrades from untenable assumptions:
Sonechkin, D.M.; & Brojewski, R. (2003). ENSO: A quasiperiodic forced dynamical system.
http://forum.decvar.org/presentations/ENSO_WORKSHOP/documents/presentations/posters/Sonechkin-poster.pdf
[Note the reference to strange nonchaotic attractors. More on this at a later date…]
The convention of basing climate studies on temperature anomalies rather than absolutes also appears to be causing some climate scientists to crucially fail to evade Simpson’s Paradox. Example of a possibly-emerging exception:
“Fig. 6 Correlations between monthly mean anomalies of surface temperature and precipitation, grouped into the 893 months of November to March and May to September, for 1979 to 2002, adapted from Trenberth and Shea (2005).”
Trenberth, K.E. (2010). Changes in precipitation with climate change.
http://www.cgd.ucar.edu/cas/Trenberth/trenberth.papers/ClimateChangeWaterCycle-rev.pdf
Dave Springer comments, “Only ocean and air currents driven by convection from lower unfrozen latitudes can remove the sea ice once it forms.”
How about persistent warm rains? It will be interesting to see what graphs vukcevic posts once he starts looking at arctic precipitation…
Jim D says:
November 13, 2010 at 12:15 pm
Ulric Lyons:
November 13, 2010 at 11:31 am
Do you rule out volcanic activity and meteor strikes as possible causes for cooling?
Anyway, I prefer this temperature plot which doesn’t have the crazy dips, rises and flat parts.
http://en.wikipedia.org/wiki/File:All_palaeotemps.png
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I have the actual data from this chart and can post a version which has timeline scale on the same basis throughout and then it can be compared to the CO2 levels (there are some problems with this data, mostly they used a smoothing function which was too long, taking out too much of the variation and it also put the timelines off quite a bit).
http://img703.imageshack.us/img703/6161/tempco2570myaroyerberne.png
This is my preferred and it is based on the same original data source but leaves more variation in and has the timelines in the proper place.
http://img213.imageshack.us/img213/1074/tempco2570mya.png
@jim D says:
November 13, 2010 at 12:15 pm
“Do you rule out volcanic activity and meteor strikes as possible causes for cooling?”
Well, it cannot be meteor strikes making a regular 150 million year cycles, and as far as I can see, volcanic activity peaks on temperature uplifts.
Ulric Lyons:
November 13, 2010 at 4:07 pm
OK, let’s take the most recent 150 million years of cooling. Is your suggestion that it is all caused by increased cloud cover that cools the earth so much that the CO2 was absorbed by the cooler ocean? Or could the more conventional idea related to sequestering CO2 by geological and biological processes have accounted for it? This makes a difference as to where the CO2 went, into the ocean or into the sediments and ground. If it is in the ocean, the current warming is worse than we thought, because that would be easily released to add to fossil carbon, but that is clearly not what is happening because the net flux is still into the ocean.
The view of the anthropogenic thermostat whips seems to be that mountainous natural variations are unimportant because the obedient CO2 highway crew bypasses such nuisances-of-nature by building gently-graded high bridges over deep valleys and by blasting gently-graded tunnels through hills. The view appears based on naive miscategorization of key factors into “internal” & “feedback” slots.
Anyone following R. de Haan’s link may (after a google search) arrives here:
Labitzke, K. (2005). On the solar cycle-QBO-relationship: a summary. Journal of Atmospheric and Solar-Terrestrial Physics 67, 45-54.
http://strat-www.met.fu-berlin.de/labitzke/summary/JASTP-Labitzke-2005.pdf
Free versions of some of Labitzke’s papers are here:
http://strat-www.met.fu-berlin.de/labitzke/
The stratosphere is relatively regular. Due to the turbulence in the troposphere, acceptance of the involvement of the sun in tropospheric dynamics appears unlikely to precede clarification of nonrandomly shared interannual lunisolar patterns that evade detection by standard methods of linear statistical inference. Methodological advances may be necessary to reach some audiences.
In the meantime, nevermind statistical inference based on untenable assumptions. Skip straight to meaningful exploratory data analysis when investigating complex systems about which you have little information (for example terrestrial climate). For a good primer on mapping conditional dependencies, see W.S. Cleveland’s book “Visualizing Data”.
http://cm.bell-labs.com/cm/ms/departments/sia/project/trellis/
There is really only one climate change event / extinction event associated with an asteroid strike, Chicxulub and the dinosaurs, 65 million years ago.
The only confirmed impact structures which are bigger than this one were 1.3 billion years ago (Sudbury Canada) and 2.0 billion years ago (Vredefort South Africa) which were both before complex life developed.
It looks like the next biggest event(s) would have been 35.5 million years when there three 5 km stikes (causing 90 and 100 km-wide craters) within a few 100,000 years of each other. No change in the climate can be ascertained at this time but there were higher than normal extinctions. There was also a 5 km strike at 214 million years ago (Manicouagan Quebec Canada) with no associated extinctions.
There are, however, at least four major extinction events associated with climate change – Ordovician extinction (major ice age and probably the coldest temperature in the last 600 million years) – the Permian extinction which was almost certainly caused by the Siberian Traps volcanic events and when temperatures fell considerably – the Devonian extinction when temperatures rose rapidly – the Triassic extinction at 200 million years ago which was likely caused by a strong cooling event as Eurasia transited the North Pole (the isotope data put the coldest part at 160 million years ago but the largest part of the landmass was over the north pole at 200 million years ago).
Paul Vaughan says:
November 13, 2010 at 12:47 pm
re; persistent warm rains melting sea ice
I wrote:
“Only ocean and air currents driven by convection from lower unfrozen latitudes can remove the sea ice once it forms.”
Isn’t rain implicit with convective air currents? The point being the water vapor forming the rain didn’t evaporate from a frozen surface. It had to come from a warmer surface. Somewhere warmer, as a general rule, would be a lower unfrozen latitude where evaporation is happening.
@jim D says:
November 13, 2010 at 4:47 pm
“OK, let’s take the most recent 150 million years of cooling. Is your suggestion that it is all caused by increased cloud cover that cools the earth so much that the CO2 was absorbed by the cooler ocean?”
150 million years of cooling ?
http://img213.imageshack.us/img213/1074/tempco2570mya.png
Read: November 12, 2010 at 6:54 pm. The suggestion was less solar activity = less water vapour = cooling (as in; Dryas). After looking particularly at 420 to 460 million years ago, we were not at all convinced the co2 mattered anyway.
Ulric Lyons,
I would base whether CO2 matters on more recent data, like satellites, and actual physics, than 450 My ago when we have incomplete information to say the least. Obviously it is possible that previous cold periods were also a result of orbital effects and continental configurations in polar areas like the recent ice ages seem to be certainly due to, but when CO2 values are elevated (which I don’t think the data is certain on), you need to find other mechanisms for cooling the earth for it to happen. In the recent Ice Ages we have low CO2 which certainly helped.
Over the weekend, I purchased a Blue Ray Video called “Mother Earth” or words to that effect. It is a home edition of an original Imax film.
One of the segments is on Antarctica; and it points out that Antarctica is the coldest (by far) and dryest; drier than any tropical desert; and also the highest Continent. I believe they said that the average altitide of Antarctica is three times whoever it is that is second. The segment included photographs from the Amundsen and Scott expeditions.
The notable thing about those photographs; and the whole film itself, was how much lcoud there is all the time over Antarctica.
So central Antarctica is PERMANENTLY below the 255 K earth orbit black body equilibrium Temperature that is usually cited for 30% albedo. And even under those conditions there is plenty of water vapor and clouds in the atmosphere.
So to argue that CO2 can get the earth started from a waterless atmosphere; but the oceans can’t at the present earth orbit location; is just plain silly. Water can start the whole system up by itself with no other GHGs of any kind.
Can I repeat just one more time; that the solar constant is 1366 W/m^2; not 341.5 W/m^2; and when that shines on a part of the earth, the Temperature does not head monotonically for a limit temperature of 255 K that it can never reach; it heads for something more like 396 K (for that sunlit portion); and that is why you cannot simply treat the earth as an isothermal body at an equilibrium temperature of 288 K all over the surface, even at the depth of the Antarctic winter midnight.
Andy Lacis just said this on Judith Curry’s blog:
Nature operates according to the laws of physics, and that is the only sensible approach to be studying the global warming problem. Opinions that are not in accord with the laws of physics, are just that – opinions, for whatever else they may be worth.
This is upside down. The laws of physics more or less reflect the way Nature operates, though every now and then they turn out to be inadequate to the task when newly observed natural phenomena defy them. Often too, it turns out we have misappplied the laws of physics, or failed to take account of not so obvious variables.
The hubris is breathtaking. This is why we get Kevin Trenberth saying:
“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.”
Notice the order of assumptions here: The data must be wrong, therefore our observing system must be inadequate. I’m sure our observing system is less than perfect, but did it really not occur to Kevin that maybe, just maybe, the empirical results were showing him that the current co2 global warming theory is up the spout?
In science, “experimentum summas judex” as Einstein said. You can have many observations which support a theory, but just one conflicting observation can falsify it. But in climate science, it appears that theory trumps experiment, and reality itself.
Climate scientists could clearly benefit from some historical perspective and a course in philosophy of science.