Bishop Hill Use and abuse of climate simulations
Dec 12, 2016 Climate: Models Some of you may be interested in Gavin's Schmidt's forthcoming talk at Exeter University. It's hard to deny his expertise in the area.
Climate change is now a constant presence in the media with many stories about the latest records in global heat, Arctic ice loss, sea level rise, or the potential for changes in extreme weather. But many people still have questions about how scientists study the Earth system, where the dramatic predictions of future change come from, and how credible they are.
In this talk Dr Schmidt will discuss the use and abuse of climate simulations, how they are used to attribute changes in the past and what they suggest for the future. He will specifically discuss how global society now has to choose its own adventure and what the implications of these choices will be.
Details here.
Reader Comments (186)
Frank, GHGs do not trap radiation as you claim, I understand what they and Argo floats do and being able to measure radiative imbalance at the sea surface isn't one of them.
Can you please prove that the very insignificant recent warming is not caused by anything other than natural cycles given that it is nothing unusual in historical temperature variations. If you can then I'll unreservedly accept it.
Minty, not so much disinterested as uninterested; big difference – while a judge must not be uninterested in a case, he must show disinterest in the persons involved.
Mr Mason, that is not too far from what I have been trying to say, throughout this thread – what is the difference between today’s unremarkable slight rise in temperatures and all the other changes (rises and falls) that have occurred through all history and pre-history? If all other changes can be explained by “unforced variation”, what is so different about the present change that cannot be explained by “unforced variation”?
Minty, not so much disinterested as uninterested; big difference – while a judge must not be uninterested in a case, he must show disinterest in the persons involved.
Mr Mason, that is not too far from what I have been trying to say, throughout this thread – what is the difference between today’s unremarkable slight rise in temperatures and all the other changes (rises and falls) that have occurred through all history and pre-history? If all other changes can be explained by “unforced variation”, what is so different about the present change that cannot be explained by “unforced variation”?
Minty, not so much disinterested as uninterested; big difference – while a judge must not be uninterested in a case, he must show disinterest in its execution.
Mr Mason, that is not too far from what I have been trying to say, throughout this thread – what is the difference between today’s slight rise in temperatures and all the other changes (rises and falls) that have occurred through all history and pre-history? If all other changes can be explained by “unforced variation”, what is so different about the present change that cannot be explained by “unforced variation”?
Minty, not so much disinterested as uninterested; big difference – while a judge must not be uninterested in a case, he must show disinterest in its execution.
Mr Mason, that is not too far from what I have been trying to say, throughout this thread – what is the difference between today’s slight rise in temperatures and all the other changes (rises and falls) that have occurred through all history and pre-history? If all other changes can be explained by “unforced variation”, what is so different about the present change that cannot be explained by “unforced variation”?
Remember Exeter is home to some thing else , the MET office whose 'expertise ' in using models will always produce the results 'required ' no matter what the data is .
Ravishing Rattie.
I get the point - no need to repeat yourself.
I claim poetic licence.
If you think about it, the BH horde is both uninterested and disinterested in most dorkish onslaughts.
Frank, not sure why you are introducing the Moon at this stage but I do agree with your explanation of Local Thermodynamic Equilibrium. I would put it to you that LTE is the ongoing process which leads to atmospheric steady state once a GE has come into being. However, the energy in the atmosphere arises from work done in the system, not on the system - insolation is red-shifted to LWIR after it has first been thermalised. It follows that measurements made in the LWIR are measurements of the effect of that in a planet with a GE, not measurements of GE cause.
Change in radiative gas concentration will upset steady state and constant change will upset that constantly. The question is though, for each incremental change in concentration, what would be the time for steady state to be re-established. You are right to point out to Martin Mason that Argo floats "have detected a radiative imbalance" and the float data have been used for that. That should be game over for sceptic objection but it is not as it raises the question of why attention has shifted to ocean temperatures (meaningfully measurable or not) when cAGW is ultimately about atmospheric temperatures.
Getting back to the subject of this thread, to my mind the use of climate models is itself an abuse as the unfounded belief in their accurately representing reality destroys our ability to analyse that reality. The whole thing needs to be started again and that idea is gaining ground as fewer and fewer predictions come to pass. Climate science job loss, including the likelihood of Gavin Schmidt's, may just be the thing to get that fully under way.
Ooops. No idea what happened , there, though my connection is presently through a satellite, so submissions can appear to be timed out. Reloading the site led me to believe that they had not been sent (or received). If there are any mods monitoring, if they could delete the first three (and this one), it would be appreciated.
Ssat: my own suspicions as to why attention has now switched to the oceans rather than land is that the oceans conditions are less monitored and less understood, so they can make up any old dross about changing conditions, and calling it the fault of CAGW (as they are doing with the Great Barrier Reef). What they seem to hope is that people will be fooled into thinking that information that is given to 3 decimal places MUST be super-accurate, even though many people will acknowledge that most thermometers in the laboratory are really only acceptably accurate to within 0.2°C; out in the field, though, that accuracy may diminish (or error margin increase) to 1°C.
What tickles me about the GCMs is that, while all are acknowledged to be wrong, the average of them seems to be being presented as being right. Would that have applied to the multiple-choice exams I had in my youth, I could be a far better qualified person, now.
ssat asked: "not sure why you are introducing the Moon"
The Moon is a model for the Earth without an atmosphere of GHGs. It receives the same amount of solar radiation as the Earth, but is not 33 K colder. So, if you quantify the GHE in terms of temperature, there is potential for confusion. If you quantify the GHE in terms of resistance to radiative cooling to space, the Earth has a large GHE (150 W/m2) and the Moon no GHE.
As for climate models, Judith Curry once had a post which discussed "fitness for purpose" of AOGCMs. What they are good for and not good for. If the conventional means of tuning climate models produced one (or a even few) set of parameters that produced a more accurate representation of all aspects of today's climate, then we might have more faith in the output of that model. In reality, climate sensitivity, regional climate change and extreme weather change dramatically in ensembles with perturbed parameters without significantly degrading their ability to reproduce today's climate. Therefore, they aren't much good for forecasting. That doesn't mean that climate models aren't useful for studying things that don't change much with parameterization. Nor does that mean that we don't need better climate models to predict the future. However, we have poured billions into models over the past three decades and don't seem to be getting any closer to a definitive answer. Gavin: What are you going to do differently that will change this situation? Otherwise why should we continue funding your highly-politicized work?
Martin Mason wrote: "Frank, GHGs do not trap radiation as you claim, I understand what they and Argo floats do and being able to measure radiative imbalance at the sea surface isn't one of them."
Martin, the question is whether what you "understand" has anything to do with reality. Social media informed million of people that a child sex ring was being run out of the Comet Ping Pong restaurant in Washington DC. Comments at this website are usually more reliable than that. A reference or more details might add some credibility to your comments.
Connection between Argo floats and the TOA radiative imbalance: The law of conservation of energy says that any difference between incoming and outgoing energy of all types (including radiation) is accounted for as internal energy - a change in temperature. Heat capacity is the factor used to convert an energy imbalance into a temperature change. (Or, if your prefer, a TOA radiative imbalance (POWER per unit area) into a RATE of temperature change.) The "effective" heat capacity of the ocean is so much larger than the heat capacity of the surface and atmosphere that more than 90% of the energy accumulating from rising GHGs ends in the ocean. (The "effective" heat capacity of the ocean depends on the depth of ocean being heated.) The ARGO network was created to accurately measure how much energy is accumulating at the site where most of energy from the current radiative imbalance should be accumulating. Since the network has been operational, the steady rise in temperature has been consistent with a TOA radiative imbalance of about 0.5 W/m2.
Since the deep ocean is so much colder than the surface of the planet and since fluid flow is chaotic, fluctuations in the currents exchanging heat between the surface and deep ocean cause variations in surface temperature that aren't forced by GHGs or changes in incoming SWR. El Nino is associated with such fluctuations. Due to its lower heat capacity, the temperature of the troposphere (as measured from space) fluctuates roughly twice as much as the surface. Along with volcanic and anthropogenic aerosols and changes in solar output (which appear to be small in the satellite era), these fluctuations obscure the slow steady steady surface warming one might otherwise expect to observe from rising GHGs.
Martin continues: Can you please prove that the very insignificant recent warming is not caused by anything other than natural cycles given that it is nothing unusual in historical temperature variations. If you can then I'll unreservedly accept it.
If you were paying attention to the statements from responsible climate scientists (or my previous comments on this post) - rather than the hysteria over CAGW - you would know that real scientists believe that the temperature record ALONE doesn't prove that recent warming is outside the range of normal variation. The consensus believes in CAGW despite AGREEING WITH YOU about the temperature record alone. For example, in response to 2013 Parliamentary inquiries, the Met Office recently wrote (http://www.metoffice.gov.uk/research/news/statistical-models-and-temperature):
"The global mean warming observed since the late 19th century is far outside the range of observational uncertainty in global temperature datasets, and there is therefore no doubt that the world has warmed. A wide range of observed climate indicators continue to show changes that are consistent with a globally warming world, and our understanding of how the climate system responds to rising greenhouse gas levels.
The analysis of the nature and causes of climate change is based on comprehensive observations of the climate system IN COMBINATION with theoretical understanding of its PHYSICS and general circulation models, themselves based on the fundamental laws of physics. Sophisticated statistics are used to demonstrate the significance of recent changes in the climate system."
In other words, you (and Radical Rodent) need to stop babbling about the temperature record alone and learn some physics: Attribution of warming to GHGs depends on AOGCMs (which I don't trust) or to an understanding of the physics of the interactions between radiation and GHGs and about the physics of feedbacks associated with warming.
Uncontroversial physics says the increasing GHGs slow radiative cooling to space. This is not "trapping" of heat by absorption, because GHGs both absorb and emit radiation. That physics is contained in the Schwarzschild eqn discussed by me above with citations. Learn some physics and I'd be glad to discuss where we and the consensus might disagree.
Frank, the Stephan-Boltzman equation uses T^4 to establish radiatively power. If the moon doesn't validate S-B then we have a problem. 33 degC has a problem. GE has a problem. Climate sensitivity has a problem. Measurement has a problem. Radiative imbalance has a problem...
I'll stick with my layman's temperature metric despite your advice but we do agree that the whole thing is a mess.
Frank, sorry to say but you are waffling. GHG's do not trap radiation as you claim, Argo buoys don't show a sea surface radiative imbalance as you claim and you can't prove that any current warming is not caused by the natural cycles that have caused it before so what credibility do you have? You have drunk the Kool Aid that's all. Why do you come on to boards like this peddling what is no more than propaganda with no scientific basis or at least no basis that you can actually understand?
Martin Mason: "Why do you come on to boards like this peddling what is no more than propaganda with no scientific basis or at least no basis that you can actually understand?"
Why do YOU come on boards like this peddling nonsense about things you finally admit not understanding and which therefore is merely propaganda? The host of this blog is the author of a fairly technical and respected book about the Hockey Stick and other temperature reconstructions. He has hosted guest posts on highly technical subjects from Nic Lewis, Doug Kennan and others.
As for me, I'm definitely not a supporter of the consensus about CAGW. I am a supporter of accurate science and feel strongly that attempts to treat solid science (such as the GHE) as a hoax hurt the credibility of those who believe that CAGW has been vastly oversold by scientists who (as Schneider suggested) "tell the public scary stories, make simplified dramatic statements and make little mention of their doubts". Both the hoaxers and alarmist damage the credibility of science, which is my profession.
ssat wrote: "If the moon doesn't validate S-B then we have a problem. 33 degC has a problem. GE has a problem. Climate sensitivity has a problem. Measurement has a problem. Radiative imbalance has a problem..."
Exactly, life gets complicated when one wants to say that the GHE is 33 degC of warming rather than a 150 W/m2 decrease in upward radiation between the surface and space. You can rely on your intuition to correctly determine that a reduction in radiative cooling will cause an increase in temperature, but there are many complications quantifying the amount of warming one expects from a change in radiative cooling to space. That is why there is so much controversy about climate sensitivity - how much warming will be caused by a 3.7 W/m2 reduction in radiative cooling space.
FWIW, the S-B equation doesn't apply to all situations, but provides the correct answer for emission from the surface of the earth. With its emissivity (e) fudge factor (W = eoT^4), it gives reasonable answers when it is not fully applicable.
The Moon is a problem because its albedo is much lower than the Earth's albedo, so it absorbs more SWR than the Earth, making it warmer. (The Earth's albedo is not independent of temperature and was higher during ice-ages.) Daytime and nighttime last 2 weeks each on the Moon. Unlike the Earth, there is no ocean or atmosphere to transfer heat from equatorial regions to polar regions. Therefore the Moon has much greater temperature extremes than the Earth. The average of T^4 does not equal ^4. So some skeptics draw false conclusions about the GHE by ignoring the substantial differences between the Earth and the Moon. Therefore, you will never be wrong or confused if you say that there is a 150 W/m2 GHE (reduction in OLR between the surface and space) due to GHGs in the Earth's atmosphere and a 0 W/m2 GHE on the Moon because it totally lacks an atmosphere. Clearly the Earth is warmer than it would be if the radiative flux to space weren't reduced while passing through our atmosphere.
Measurement does have problems. The instruments in space that measure incoming SWR (342 W/m2) and outgoing LWR (240 W/m2) and reflected SWR (102 W/m2) from space aren't accurate enough to accurately detect a 0.5 W/m2 difference between the former and the sum of the latter two. That requires an absolute accuracy of about +/-0.2%. That is why we built Argo. Fortunately, these instrument errors are constant, no surprise to the scientists who built the equipment, and don't prevent us for detecting CHANGES of a few tenths of a W/m2.
And don't forget chaos makes it hard to attribute change to GHGs.
One of the biggest problems with the IPCC is that they ignore some aspects of uncertainty in their SPMs, thereby creating the overconfidence in supporters of CAGW. This provides opportunities for even more overconfident skeptics to cry "Hoax".
Frank, are you based in the UK and, if so, will you be attending Gavin's talk?
I do hope that someone like you will be there to ask the 'hard' questions, though I fully expect they will be 'selected' so as not to raise any doubts or uncertainties... and to protect the speaker from any embarrassment :-)
Frank (Jan 1, 2017 at 9:37 PM), you wrote “The ARGO network was created to accurately measure how much energy is accumulating at the site where most of energy from the current radiative imbalance should be accumulating. Since the network has been operational, the steady rise in temperature has been consistent with a TOA radiative imbalance of about 0.5 W/m2”, but I wonder what the uncertainty is on that number?
A quick google search found this paper…
http://www.ocean-sci.net/10/547/2014/os-10-547-2014.pdf
… that used Argo data to derive a value of 0.5 ± 0.1 Wm2, while another paper from 2012…
http://www.nature.com/ngeo/journal/v5/n2/abs/ngeo1375.html
…used Argo and satellite data to derive a value of 0.50 ± 0.43 Wm2.
Though such variations in uncertainty are likely due to differences in analysis method, they do suggest that the measurement of radiative imbalance is still a work in progress.
When it became obvious, a few years ago, that CAGW was an ongoing hoax, many sceptics wondered how the self-styled "consensus" would get out of the hole it had evidently dug for itself. We even expressed concern that science itself was becoming "post-truth". What would happen?
Few could have anticipated that the "consensus" solution was to re-write history and claim that they had never lined up in support of the CAGW theory in the first place. Indeed some supporters of the (still self-styled) "consensus" now contend that CAGW is a just a "snarl" word used only by "deniers" to discredit "the science".
Despite these "consensus" denials of CAGW, the entire UK politico-industrial complex (and I understand those of other countries too) is driven by the fear of future man made climate catastrophe that can (supposedly) be "tackled" by drastically eliminating CO2 emissions created by burning natural (sorry, "fossil") fuels. So whatever Frank says, CAGW is alive and well in the corridors of power.
I'm reformatting my Dork of Cork Comment Generator for the new year. Can you all help? I need sixteen of his most used words/phrases to put in a 4x4 grid, ready for random sentence generation. Ta.
Dave Salt wrote: "Since the network has been operational, the steady rise in temperature has been consistent with a TOA radiative imbalance of about 0.5 W/m2”, but I wonder what the uncertainty is on that number?"
I have a lot of questions about this subject that I have not tried to answer before. I have calculated that an imbalance of 1 W/m2 is capable of warming the mixed layer of the ocean (top 50 m) at a rate of 0.2 K/yr. (A useful number to remember.) So, 0.5 W/m2 warming a 100 m layer would be 0.5 K/decade/100 m. Usually accumulation of heat into several layers is reported: 0-100 m, 100-300 m, 300-700 m, and 700-2000 m. IIRC, the top layer lost heat during and 1/3 of the heat accumulation has been in the 700-2000 m layer. If I have calculated this correctly and if 1/3 of the heat went into the 700-2000 m layer, that would be a warming rate of 0.013 K/decade, small enough to raise questions in my mind. Looking, I find that the temperature measurements are supposed to be stable within 0.005 K and we have 3000 floats making measurements every 10? days. Absent systematic errors, even 0.01 K/decade seems like it could be meaningful despite the small numbers. Furthermore, the ARGO system was designed to provide useful answer to the radiation imbalance issue and therefore wouldn't have been deployed without the technical capability to do so.
https://www.researchgate.net/publication/226297545_Stability_of_Temperature_and_Conductivity_Sensors_of_Argo_Profiling_Floats
http://www.ocean-sci.net/7/783/2011/os-7-783-2011.pdf
The paper with 0.5+/-0.1 W/m2 is 2005-2012 and uses only ARGO data. The paper with 0.50+/-0.43 W/m2 is from 2000-2010, before the ARGO network was complete and relied on data from XBT data, which underwent major correction. IMO, the sudden slowing of warming during transition period from XBT to ARGO data seemed dubious. (Before ARGO, ocean heat content was often average over 5 years, because the year to year changes could be unrealistically large.)
BTW, although I have bowed out of this discussion, for the sake of the record, it was climate science that stated that the Greenhouse Effect was 33degC/K, not me.
Frank, sorry but as I said you are waffling. Was it the actual data from the Argo buoys or the adjusted data?
Frank, do Argo buoys measure a radiative imbalance at the sea surface?
Can you prove unequivocally that the recent fairly insignificant warming was caused by man made CO2 rather than natural variation?
Where can we see the radiation imbalances that are causing catastrophic warming or any warming? Where is the equatorial tropospheric hot spot?
Where is any proof that MM CO2 emissions are causing anything but a benefit for the world?
Best wishes
"What tickles me about the GCMs is that, while all are acknowledged to be wrong, the average of them seems to be being presented as being right." --√🐁
As has been oft said before, the thinking there is akin to saying, "If you put enough garbage in one pile, it becomes caviar." Yet another example of how far Science has fallen.
"I'm reformatting my Dork of Cork Comment Generator for the new year. Can you all help? I need sixteen of his most used words/phrases to put in a 4x4 grid, ready for random sentence generation. Ta." --Shindig
#1. "That would be an ecumenical matter." Oh. Wait. Wrong Irishman.
"If you think about it, the BH horde is both uninterested and disinterested in most dorkish onslaughts." --Supertroll
Yes, most. I rather enjoy their panache, their sound and fury, and I suspect they signify something, but I can only wish I knew what. Blessings be upon the D of C. And a Happy New Year to him and to all.
Frank (Jan 2, 2017 at 8:21 PM) said “…the ARGO system was designed to provide useful answer to the radiation imbalance issue and therefore wouldn't have been deployed without the technical capability to do so.”
I don’t doubt the accuracy to measure temperatures under controlled laboratory conditions, which the Argo FAQ says is ± 0.002°C. However, an instrument’s measurement accuracy is very different from its ability to measure the bulk temperature of its surroundings, especially when the temperature variations of those surroundings is rather dynamic. I therefore assume that the key to solving this problem lies in the statistical analysis of the data history. However, I’ll note that some discrepancies have already been identified…
http://onlinelibrary.wiley.com/doi/10.1029/2006JC003825/epdf
…but again assume that this has been noted and corrected for within later analysis.
I guess my point is that the evidence for radiative imbalance still seems to have some big question marks against it, which means that our degree (pardon the pun :-) of certainty about the anthropogenic contribution to global warming still remains insufficient to justify draconian measures to combat it.
Martin asked the following questions:
1) Was it the actual data from the Argo buoys or the adjusted data?
All data undergoes some processing to produce a "data product". Monthly averages are calculated from all of the data collected from a grid cell. Quality control discards outliers (<1% of the data). Unlike land and SST records, there are no corrections for equipment changes, TOB, breakpoint homogenization, wooden buckets, canvas buckets, engine intake, buoys etc. As best I can tell, there is far less processing of the ARGO record (which measure temperature directly) than the UAH/RSS tropospheric records (which measure radiance, merge data from different satellites, correct for satellite drift, etc) and than for any other temperature records. I haven't heard any complaints about ARGO from professional climate scientists who are skeptics. When ARGO was getting started, skeptic Roger Pielke Sr was a big advocate of this approach to measuring the planet's radiative imbalance.
There is an ocean heat uptake record that goes back to the 1960s and used XBT in the 1990s (which were highly adjusted). Most people only cite only the pure ARGO data now that it is about a decade long. IMO, you have good reasons to be suspicious of anything before ARGO. Above Dave cited a paper with a rate of 0.50+/-0.43 W/m2 for 2001-2010, a period with both XBT and ARGO data. Given the uncertainty and corrections, this isn't meaningful.
2) Frank, do Argo buoys measure a radiative imbalance at the sea surface?
They measure the change in ocean temperature down to 2000 m and convert temperature change in a vertical column of water to the power flux needed to produce that change in temperature.
The heat capacity of the atmosphere is 7% of the heat capacity of the top 50 m of the ocean - the mixed layer which is stirred by surface winds and has a temperature rises and falls with the seasons. More than half the heat entering the ocean goes below the mixed layer. For practical purposes, ARGO is measuring the radiative imbalance at the TOA as well as at the ocean surface.
3) Can you prove unequivocally that the recent fairly insignificant warming was caused by man made CO2 rather than natural variation?
That depends on your definition of "unequivocal". Climate scientists do NOT claim that they can attribute warming to CO2 using the temperature record ALONE. Unforced and natural variability are too big. Using AOGCMs to estimate unforced and natural variability, the IPCC attributes at least 50% of warming to CO2 (and other anthropogenic effects) and believes 100% is the best estimate. I disagree - AOGCMs can probably be tuned to assign all or any desored amount warming to man. And their ability to represent unforced variability is suspect.
I can unequivocally prove that rising GHGs slow radiative cooling to space and therefore must warm the planet in the long run. Based on what I know about no-feedbacks climate sensitivity and feedbacks, I'm confident ECS and TCR are not much lower than 1 K/doubling and that therefore at least 50% of warming is due to GHGs. Reasonably confident isn't unequivocal.
4a) Where can we see the radiation imbalances that are causing catastrophic warming or any warming?
ARGO. And in the calculated reduction in radiative cooling to space from increasing CO2. These calculations are based on solid numbers and theory verified in reproducible, controlled laboratory experiments. Our planet is a lousy place to do experiments: Small changes takes decades. Nothing is reproducible or well-controlled. Climate behaves chaotically.
(If temperature fell 0.4 K over the next two decades, my conclusion wouldn't change - but my estimate of unforced variability would go up.)
4b) Where is the equatorial tropospheric hot spot?
It is present during major El Ninos, when it is easiest to detect. It is clearly missing from almost all analyses of multi-decade warming (where its detection is more challenging).
The critical question is what does the absence of a hot spot imply? Answer: The lapse rate is not changing as expected with surface warming. The lapse rate is not directly changed by GHGs; it is changed by rising absolute humidity. So it is the combined WV-LR feedback that is not behaving as expected - and surface warming is less than models project. The idea that rising GHGs cause warming isn't being challenged by the missing hotspot - despite the IPCC's ludicrous claims of at "fingerprint" for GHG-mediated warming. Stratospheric cooling is useful, but destruction of ozone also causes cooling there.
5) Where is any proof that MM CO2 emissions are causing anything but a benefit for the world?
I don't claim any expertise in this area. My understanding is that essentially all economists think 20th century warming was net-beneficial, but that future warming will start being net harmful with 0-1 K more warming. The goal of limiting warming to 1.5 or 2.0 K is a purely political and not supported by economists or cost benefit analysis - and insane given the benefit of past warming and the uncertainty about when harm will begin. Supposedly the costs of mitigation will be mostly borne by people in the 21st-century, but the benefits mostly won't accrue until the 22nd-century. If we don't ruin our economy, the 22nd century should be far wealthier than today and better able to bear the cost of adaptation than the developing world and the less-affluent can bear the cost of mitigation today. Without a binding international treaty (:)), countries, that reduce emissions won't be guaranteed to receiving any benefits in the future. (The US calculation of the social cost of carbon by counting the total benefits from global reductions against the costs paid by Americans - if you even think such calculations are meaningful.) Finally, US Social Security will be insolvent in about 15 years - beyond any doubt - but our government hasn't take the action needed now to avoid this catastrophe. No one in their right mind should expect such a government to spend money effectively to address a poorly-understood problem a half-century or more in the future, when it isn't doing anything to avoid the SS train wreck. Nevertheless, the Dems scream about the ill-defined problem and ignore the unambiguous problem.
Unambiguous Harm #1: Rising temperature increase transpiration by crops and other plants. Drought is therefore caused by lack of rainfall AND heat. In areas where water is a limiting factor, yields will drop without increased irrigation. In northern China, the Western US and elsewhere, we are already using most of the surface runoff and are depleting aquifers. (Elsewhere CO2 will make crops grow faster, but they will probably contain few nutrients (which require nitrogen and phosphorus.) Genetic engineering may help.
Unambiguous Harm #2: As the last ice age ended and GMST rose about 5 K, sea level rose 120 m or 24 m/K. It took 10 millennia, but the rate was 1 m/century. Sea level was at least 5 m higher during the last interglacial, which was perhaps as warm as it is today. So the potential for SLR is tremendous. The question is: How long will it take? There is absolutely no evidence today for the acceleration of SLR needed to produce even 1 m of rise this century and we survived 9" of rise last century without noticing. The Holocene Climate Optimum doesn't appear to have hurt Greenland's ice cap.
I haven't studied this issue much: a) Rising temperature certainly causes more evaporation from the leaves of crops (transpiration) and this will certainly reduce crop yields in regions where water limits growth. Essentially all of the water flowing in major northern Chinese and Western US rivers is being used for agriculture and people. Where water is plentiful, rising CO2 will increase crop growth.
Best wishes
Frank (Jan 3, 2017 at 10:43 AM), you wrote ”…Dave cited a paper with a rate of 0.50+/-0.43 W/m2 for 2001-2010, a period with both XBT and ARGO data”.
Just to be clear on this, the paper also stated that the “…combined XBT and Argo data show a warming of 0.64 ± 0.11 Wm2 in the upper ocean between 1993 and 2008”, which was a value referenced from a previous paper. So this paper's aim was to reassess this value, based upon an improved understanding of all the associated errors and uncertainties.
Given that the error in the subsequent ‘Argo only’ estimates (i.e. 0.5 ± 0.1 Wm2) is so close to the 1993-2008 values quoted in the paper (i.e. 0.64 ± 0.11 Wm2), I don’t understand why you say “Given the uncertainty and corrections, this isn't meaningful “. Can I assume this relates to what you said in your previous post that “ IMO, the sudden slowing of warming during transition period from XBT to ARGO data seemed dubious”?
Nice exposition, Frank, but neither harms #1 nor #2 are unambiguous. Droughts are unpredictable enough that increased transpiration may not cause the harm. Also, warmer and enriched CO2 will help a lot. Sea level rise is highly unlikely to occur beyond our ability to adapt with relative ease.
All in all, though, you've got the problem well in hand, even on the economics from which you shy.
=============
Dave: I made my skeptical comments when asked whether ARGO was trustworthy. IMO, the answer is yes, but there are complications when the ARGO record is combined with earlier data that has problems. When the first ARGO data came out the rate of ocean warming dropped by about 2/3rds. After a lot of processing, the junction looks more reasonable.
This post (and the preceding one) discuss the problems with measuring ocean heat content with XBTs (the main source of data before ARGO) and some of the divergent analyses of that data.
https://scienceofdoom.com/2010/03/07/the-real-measure-of-global-warming-and-the-sad-case-of-the-expendable-bathythermographs/
I'm sure that the ocean has warmed since 1970 as the surface has warmed. However, when you have confidence intervals as big as the central estimate, when the corrections that are being made have a major impact on the final result, when sampling of the deeper ocean is inadequate, and when five year averages are plotted because annual averages have unrealistically large changes, IMO it doesn't make any sense to pay attention to the QUANTITATIVE results. Not when I have ARGO available. Nevertheless, professional oceanographers have tried their best to abstract meaningful results from the flawed data we possess. We can't go back in time and collect more.
Kim wrote: "Droughts are unpredictable enough that increased transpiration may not cause the harm."
I used to think that drought meant lack of rainfall and rainfall is highly variable. AGW should produce more rainfall, so why should drought increase? Rising temperature and transpiration turns out to be more important than the expected total increase in global rainfall (2%/K according to AOGCMs). It is a difficult field to understand.
Congratulations in getting a mention, nay recommendation, for your book The Hockey Stick Illusion in this interview of 'Climate Heretic' the Cyrus Fogg Brackett Professor of Physics, Emeritus, in the Department of Physics at Princeton University William Happer:
http://www.thebestschools.org/special/karoly-happer-dialogue-global-warming/william-happer-interview/
Frank, yes, I've read the warmist handbook but you are talking about unproven theories not data supported facts, minor theoretical forcings that are swamped by our ignorance of the systems and their massive uncertainties. Please unequivocally, or beyond any reasonable doubt prove that any warming that is happening now is not caused by natural cycles including any at the sea surface. The science is settled and we're destroying economies by acting on it so this should be easy.
Can you explain why there is no tropical tropospheric hot spot when that is the signature of MMGW. How about no increase in DWLR radiation despite increasing CO2 or how we have had warmer periods previously with far less CO2? Can you perhaps explain why the predicted increase in extreme weather events have not happened but exactly the opposite. Do you assume that because we are in a warming period and CO2 is increasing that there now has to be a causal relationship when none has ever existed?
I would take an hour out and watch the John Christy video on WUWT and perhaps start to think about reasons why the predictions from climate models are so abysmal and the claims of the MMCC industry so absurd. One real possibility is that is that the basic theory on CO2 as a significant climate changer is incorrect? Seems to me now that the consensus science becomes more and more discredited and that the political side is fast unravelling.
Martin: The theory of how thermal infrared radiation interacts with GHGs is called quantum mechanics. It is hardly unproven. It guarantees that rising CO2 will slow down the rate at which radiation escapes to space. That will produce some warming. About 1 K of warming per doubling of CO2 if the Earth behaved like a blackbody (ie has no feedbacks). This is the only part of AGW that can be characterized as "settled science", but it is settled.
I don't have to prove that recent warming is natural or unforced. It doesn't make ANY difference! Natural variability and unforced variability both raise and lower temperature. Rising CO2 only causes warming. If CO2 rises high enough, the warming it causes will eventually rise above the noise from natural and unforced variability! Even if you hypothesize that natural and unforced variability can cause 1 K of warming (RWP) or cooling (LIA), the signal from rising CO2 will overwhelm them - IF climate sensitivity is high. IF climate sensitivity is high, 1 K of cooling from whatever caused the LIA won't help much with 2X or 3XCO2 in the atmosphere.
The alarmists use the precautionary principle to place the burden of proof on us: Skeptics (including me) "MUST" stop using fossil fuels unless they can PROVE that climate sensitivity is NOT high. "We only have one planet".
I've always had a lot of respect for Christy, but much of that disappeared with his recent submission to the EPA attempting to show by linear regression that CO2 doesn't cause warming. Cumulative MEI and time cause warming, but CO2 does not?
As Roger Pielke says, the predicted increase in extreme weather events will take about a half-century to be detected with confidence against the background of natural climate variability. An increase in short intense rainfall (the type that causes flash floods) has supposedly been detected.
Frank, I know what quantum mechanics says but it is still theory and though it may happen under controlled laboratory conditions in a vacuum it doesn’t necessarily follow on that it applies under chaotic atmospheric conditions which can react to forcings in many ways. The reality is that there has never been a causal relationship other than CO2 rise lagging temperature rise as I believe it is still doing.
It is very easy to confuse theory and opinion as fact but the situation is vastly more complex and uncertain than the simple analysis would suggest. It is an unproven theory that DLW radiation from additional CO2 heats the atmosphere and a theory that seems to be ever more falsified by observable data. Is there any quantifiable data which actually supports the theory?
Warmists in general don't understand the precautionary principle is. To apply it you need the probability and cost of specific future events (neither is known) and to compare these with the cost of either investing now to prevent the event or to adapt as time goes on. Reducing carbon emissions now is the lunatic solution.
We know really that there is no unequivocal proof from theory or from observable historic and current data that shows that CO2 is causing any significant warming or climate change and it isn’t only JC that is pointing out this Elephant in the room. “Supposedly?”, “will happen in the future?” Yes, we've been getting this for many years now.
Martin wrote: "I know what quantum mechanics says but it is still theory and though it may happen under controlled laboratory conditions in a vacuum it doesn’t necessarily follow on that it applies under chaotic atmospheric conditions which can react to forcings in many ways."
The nice thing about laboratory experiments is that they can be and have been run under well-controlled and reproducible conditions that can be systematically varied to explore all of the conditions that will be encountered in the atmosphere. Pressure and temperature have a significant influence on the strength of the interaction between radiation and GHGs, so the spectra of major GHGs have been studied under ALL conditions that are encountered in the atmosphere, including mixtures. (For studying molecules at very low pressure, one laboratory created a spectrometer with a path length of almost 0.2 kilometers.) Water vapor forms dimers and other aggregates near saturation at atmospheric pressure, so their behavior has been studied unusually carefully.
Then scientists have shown that the predictions from laboratory experiments agree with observations of the real atmosphere. They've sent up radiosondes to sample the temperature and humidity of all levels of the atmosphere overhead and shown that the spectrum of DLR arriving at the surface agrees with the values calculated from laboratory experiments. And observed the spectrum of OLR rising through the atmosphere to a spectrometer in space. The slight change in this spectrum due to rising CO2 since the early space age has been detected (which is tough since the total change is only 1% of OLR and is spread over many wave lengths. It is lunacy to suggest that the theory of radiative forcing hasn't been thoroughly tested.
Finally, even if the theory of QM dies, a new theory will still need to make the same predictions about radiation and GHGs; because we have experimental evidence for how they behave. Relativity and QM didn't make radically different prediction about gravity or thermodynamics in areas where careful experimentation had validated theories that are now somewhat obsolete. These new theories made surprising predictions about areas BEYOND previous experiments, but not within the scope of previous validation. If QM dies, radiative forcing should live on.
To paraphrase Feynman, if you don't like the way radiation and GHGs behave, go to another universe ... where the rules are more appealing. https://www.youtube.com/watch?v=iMDTcMD6pOw
Skeptics (in their own universe) ignore radiative forcing and whine about the lack of apparent warming during the Pause and excessive warming from 1920-1940. Relying on the temperature record of a system that behaves chaotically and has shown large fluctuations in the past! Citing discrepancies of a few tenths of a degC in records mostly collected by amateurs using technology never intended to produce a record accurate to a few tenths of a degC! The satellite record (UAH/RSS) was designed to measure global temperature change in the troposphere accurately, but tropospheric temperature is highly variable (see the peaks due to El Nino). Nevertheless, it shows statistically significant warming over the past 35 years. ARGO was designed to accurately measure temperature change in the ocean. Its record shows much less noise and statistically significant warming. It is lunacy to ignore the unambiguous evidence for warming over the period when radiative forcing grown significantly (315 ppm 1960 to 400+ ppm today).
ATTRIBUTION of ALL warming to rising CO2 is an area of legitimate controversy. I think the IPCC is overconfident in attribution for many of the reasons you cite. And the projections of warming from AOGCMs are dubious at best. And even if CAGW were real, I'm skeptical that my government can deal with it in a cost-effective manner and obtain the essential international cooperation. Adaptation could be the best strategy.
I presume that Christy (like essentially all professional scientists who question the IPCC consensus) accepts the theory of radiative forcing; he is questioning climate sensitivity (and therefore feedbacks): The amount of warming one should expect from a given forcing. (Please tell me when in the video he rejects radiative forcing.) And there is plenty of room for debate about this subject. I think the activists have exaggerated the possibility that climate sensitivity is high to encourage governments to act. As Schneider infamously said: Tell scary stories, make simplified dramatic statements and hide doubts. I suspect we agree on this.
Above, you were discussing cost-benefit analysis, not the precautionary principle. From Wikipedia, "The 1998 Wingspread Statement on the Precautionary Principle summarises the principle this way: "When an activity raises threats of harm to human health or the environment, precautionary measures should be taken even if some cause and effect relationships are not fully established scientifically." And today's environmentalists and the Left use an extreme version of this principle to strangle technological progress. Nothing man-made can be proven "safe"; it's "unnatural". Despite the fact that Nature has been practicing chemical and biological warfare and survival of the fittest for millions of years, only unnatural things are dangerous. Idiocy. So, all but a few million elites should return to subsistence farming or perhaps hunter-gathering, because we are a plague on a benevolent Nature.
Data is often a series of numbers and is totally useless. Converting data to information is a skill and is clearly open to abuse. There is a need for a high level of trust in the people doing this conversion work, they need to be squeaky clean. I am a trained business analyst and I can tell you, let any bias through and you are finished.
p.s. The example we were given (in the pre PC world) was data =362836. information was 36,28,36