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Tom Curtis at 15:05 PM on 24 October 2013Why climate change contrarians owe us a (scientific) explanation
KR @100, I agree with everything you say. I just think that when discussion of increased warming was easy (as it was till 2007), in an attempt to keep it simple we (meaning the defenders of climate science in general, not any particular person, nor SkS specifically) have helped establish the strawman the deniers are now arguing. Shame on them, as you say, for they should know better. But we (see above) have helped prepare the fertile ground for their lies.
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Tom Curtis at 15:01 PM on 24 October 2013Why climate change contrarians owe us a (scientific) explanation
DSL @97, by AGW I mean the theory that:
1) Human's have caused a rapid increase in well mixed greenhouse gases over the last 150 odd years;
2) That this increase has lead to a rapid rise in GMST, and more specifically, is responsible for at least half of the rise in GMST since 1950; and
3) That unrestrained, a continuation of the rapid increase in well mixed greenhouse gases will lead to net effects which are bad, and possibly disasterous for humans and ecosystems.
I think clause (1) is so well established as to be unassailable under and plausible analysis of the data. It is technically up for grabs in the face of recalcitrant data, but only in the trivial and uninteresting way that the oblate spheroid shape of the Earth is also up for grabs.
I think that (2) would be falsified for all practical purposes should we have a rapid decline in temperature in the next five years despite strong El Ninos and no volcanism. Such a circumstance would only be compatible with the theory with a most unusual concurrence of other data - so unusual as to not be worth considering in hypotheticals. It would demonstrate both that climate sensitivity to greenhouse gases was very low (< 1 C per doubling of CO2) and that there was a strong and large internal mode of variation in surface heat content that explained most of the increase in temperature over the twentieth century. It would also demonstrate that climate sensitivity with respect to internal modes of variation was very different from that due to external forcings, which would be odd to say the least. Needless to say, I consider such a prospect very unlikely under current evidence.
This definition of AGW, which I believe to be close to that which is generally assumed, may explain one difference between me and doug-bostrom. He may include the theory of the atmospheric greenhouse effect in the theory of AGW itself, whereas I do not. It contributes to our understanding of AGW, but is a separate theory just as the theory of black body radiation is a seperate theory, and the ideal gas laws are a separate theory, and the theory of universal gravitation is a separate theory (all of which are distinct from, but contribute to the theory of the atmospheric greenhouse effect). Thus, a five year rapid decine in temperatures as specified above would not call into question the theory of the atmospheric greenhouse effect, which is sufficiently well established as to be practically unassailable. It would call into question the nature and sign of the feedback response to warming by the atmospheric greenhouse effect, which is a different matter.
I find your background on this issue from discussions with the general public interesting. It certainly helps understand the tack you take. Never-the-less I believe it is always better to ensure your presentation is accurate and balanced with respect to the theory rather than with respect to what your interlocuter needs to learn. That requires some skill in discussion, but the alternative is that you replace one strawman view with the theory with another strawman view of the theory.
A part of the attraction of climate change denial is (IMO) simply the fact that the greenhouse effect is most often explained in terms of the unphysical grey slab model. Bright people apply themselves to the physics of that model and realize it is unphysical, and reject the greenhouse effect as a result. They do not pause to remember (if they were ever told) that that model was just a teaching tool, not the theory itself.
In a similar manner, public and media focus on rising temperatures have set us up for the rhetoric of the "pause". The theory of AGW was explained and justified in too simplistic a manner. Our own educators have established the strawman which the deniers now argue. I would hate for our response to that predicament to establish yet another strawman view of AGW.
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dana1981 at 14:44 PM on 24 October 2013Fox News defends global warming false balance by denying the 97% consensus
Terranova - the Cook et al. (2013) study included papers researching the impacts of climate change. When I say "climate scientists", I'm referring to anyone actively researching some aspect of the climate, including impacts. Hence I have to disagree with you.
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Doug Bostrom at 14:34 PM on 24 October 2013Fox News defends global warming false balance by denying the 97% consensus
Sorry folks but I'm stuck at Terranova's "The 97% consensus you refer to is among climate scientists only."
A cursory glance at abstracts tested in the paper shows that there are a plethora of researchers authoring tested papers who cannot by the farthest stretch of imagination be characterized as "climate scientists." I didn't bother to check but I'll stick my neck out and hazard a guess that it's possible most of the authors surveyed in the work are not climate scientists.
That is, unless by "climate scientist" we're rebadging forestry agronomists, botanists specializing in gymnosperms and a host of other people working in numerous disciplines that happen to be touched by climate change as "climate scientists." These are all included in results leading to the 97% figure, are not included in the "not climate related" categorization.
So whatever other quibbles we may have with Terranova or Dana, Terranova's characterization of the paper is incorrect.
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Tom Curtis at 13:57 PM on 24 October 2013Fox News defends global warming false balance by denying the 97% consensus
Terranova @8, again would you clarrify, by AGW do you mean the theory that states (among other things) that anthropogenic factors caused most (>50%) of the increase in GMST since 1950? Or are you using "AGW" incorrectly to refer to the theory that CO2 is a greenhouse gas?
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Tom Curtis at 13:51 PM on 24 October 2013Fox News defends global warming false balance by denying the 97% consensus
Terranova @4, could you state clearly for the record whether or not you agree that the expected climate response to a doubling of CO2 is approximately 3 degrees C? I just wish to confirm that your disagreement is with Dana really is "...in the overall effects of the temperature increase." More specifically, I wish to confirm that you are not actually diverging with unrealistically low estimates of climate sensitivity as well.
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Tom Curtis at 13:47 PM on 24 October 2013Fox News defends global warming false balance by denying the 97% consensus
doug bostrom @7, the concensus paper does not test the level of concensus among non-climate scientists. Rather, it tests the level of concensus among non-climate scientists who write papers on the impacts or methods of mitigation of climate science, ie, a biases sub-sample of non climate scientists. Based on Doran 2009, only around 76% of non-climate scientists not actively publishing on climate science accept the consensus, possibly a little less as Doran's question 2 is weaker than the position tested in the concensus paper.
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John Hartz at 13:28 PM on 24 October 2013Fox News defends global warming false balance by denying the 97% consensus
@ Terranova #8:
You state:
I really don't know any sane academician with any sort of science background who disagrees with AGW. They do, however, disagree with the catastrophic predictions.
Is this staatement based on your personal inteactions with "sane academicians"?
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Rob Honeycutt at 12:06 PM on 24 October 2013Fox News defends global warming false balance by denying the 97% consensus
Terranova... Here you are making a number of assumptions that I would suggest are erroneous.
One would be that Dana thinks that those who aren't climate scientists (per se) can't comment or have an opinion. Voices are clearly not being silenced, but the research and the people who are actively doing research are probably the best informed regarding their areas of expertise. Where people get in trouble is when someone without specific expertise is trying to claim the those who do have expertise are wrong. And this happens quite a lot in climate science.
Another would be that the 97% only counts climate scientists. The 97% in Cook 2013 refers to research papers, not scientists. Oreskes and Cook refer to papers on global warming. Doran and Anderegg refer to climate scientists.
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barry1487 at 12:02 PM on 24 October 2013Fox News defends global warming false balance by denying the 97% consensus
Terranova,
"other science disciplines... have a say in the matter of the complicated geosphere, hydrosphere, biosphere, etc"
The Consensus Project list of papers was compiled under the search terms "global warming" and "global climate change." No discipline that has published on the topic was filtered out.
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chriskoz at 11:54 AM on 24 October 2013Fox News defends global warming false balance by denying the 97% consensus
Terranova@6,
As doug_bostrom explained to you, what Dana meant with the "less than 3 percent of climate scientists" sentence you're nit-picking so persistently, is "less than 3 percent of scientists publishing in the peer reviewed climate journals". I agree, that your nit-pick makes sense (i.e. Dana should have been more careful in his wording) but, unlike yourself, I don't conclude unsupported & demostrably wrong claims out of it.
Your nit-pick would make sense if it contributed to the improvement of the article or to our understanding of related scientific facts. But it does not: it is actually meant to confuse the facts, so I suggest you stop doing it.
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Terranova at 11:50 AM on 24 October 2013Fox News defends global warming false balance by denying the 97% consensus
Doug,
I am directly referring to Dana's quote in the first paragraph of this post. I am not referring to the paper he mentions later in the article which is separate. I really don't know any sane academician with any sort of science background who disagrees with AGW. They do, however, disagree with the catastrophic predictions. And, that disagreement should not be referred to as denialism and contrarianism. Just as I refrain from using words like alarmism.
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Doug Bostrom at 11:29 AM on 24 October 2013Fox News defends global warming false balance by denying the 97% consensus
Terranova, what you said was "the 97% consensus you refer to is among climate scientists only." You go on to say "That percentage moves downward as you move away from strictly climate scientists."
Tested against the fact of the paper, the reason we're speaking of "97%," those statements are plainly wrong. Thus you are mischaracterizing the paper Dana is talking about.
This is an extremely easy conversation to end. No loss of face is involved. You can easily search the abstracts used in the paper and demonstrate how your assumption was incorrect.
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Terranova at 11:20 AM on 24 October 2013Fox News defends global warming false balance by denying the 97% consensus
Doug,
You are correct about the paper you referred to, but that is not what Dana referred to. Reference Dana's second sentence in the first paragraph: "This is in large part a result of disproportionate representation of the less than 3 percent of climate scientists who are 'skeptical' of human-caused global warming,..." Emphasis mine.
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Doug Bostrom at 11:15 AM on 24 October 2013Fox News defends global warming false balance by denying the 97% consensus
Terranova, if you look at the paper in question you'll see that the 97% figure does not pertain only to climate scientists.
Abstract:
"We analyze the evolution of the scientific consensus on anthropogenic global warming (AGW) in the peer-reviewed scientific literature, examining 11 944 climate abstracts from 1991–2011 matching the topics ‘global climate change’ or ‘global warming’. We find that 66.4% of abstracts expressed no position on AGW, 32.6% endorsed AGW, 0.7% rejected AGW and 0.3% were uncertain about the cause of global warming. Among abstracts expressing a position on AGW, 97.1% endorsed the consensus position that humans are causing global warming. In a second phase of this study, we invited authors to rate their own papers. Compared to abstract ratings, a smaller percentage of self-rated papers expressed no position on AGW (35.5%). Among self-rated papers expressing a position on AGW, 97.2% endorsed the consensus. For both abstract ratings and authors’ self-ratings, the percentage of endorsements among papers expressing a position on AGW marginally increased over time. Our analysis indicates that the number of papers rejecting the consensus on AGW is a vanishingly small proportion of the published research.
Notice that the papers selected were not filtered by author discipline, which means that your hypothesis "the 97% consensus you refer to is among climate scientists only" is plainly incorrect.
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Terranova at 10:46 AM on 24 October 2013Fox News defends global warming false balance by denying the 97% consensus
Dana,
You and I have a very similar background in risk management for large consulting firms. I am older than you and have since moved on and entered the field of academia. I hold a B.S. in Biology and an M.S in Fisheries and Wildlife. I am working on an M.S. in Biological Sciences which I plan on following with a PhD. I still consult with various companies pertaining to risk management, and EHS managment.
The 97% consensus you refer to is among climate scientists only. That percentage moves downward as you move away from strictly climate scientists. I would argue that there are a myriad of other science disciplines that have a say in the matter of the complicated geosphere, hydrosphere, biosphere, etc... that we live on and in. As I am sure you know, all the spheres are interconnected and have reciprocal interactions.Let me clearly state that CO2 is a GHG, and anthropogenic releases of this GHG along with land use changes contribute to an increase in overall global temperature. Where we diverge is in the overall effects of the temperature increase.
Scientists are trained to be logical and to process data. If only "climate scientists" are capable of intellectually commenting on global warming, then that silences a lot of voices. Including mine and yours...Moderator Response:[JH] Dana is on vacation and may not be able to respond to you for a couple of weeks.
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Jubble at 08:08 AM on 24 October 2013Fox News defends global warming false balance by denying the 97% consensus
Help needed. I'm hoping this comment is relevant to the topic, as an example of denial in the media. I'm trying out the UK Press Complaints Commission process to see how it goes. I wrote a complaint about the following article (my complaint is at the bottom of this post):
http://www.telegraph.co.uk/earth/environment/climatechange/10310712/Top-climate-scientists-admit-global-warming-forecasts-were-wrong.html
And got the following response from the Telegraph via the PCC:
http://john-bell.com/?attachment_id=415
I'm away next week so will need to respond to this on Friday - any thoughts on how I should respond very welcome.
Complaint:
The overall complaint is that the article misleads by highlighting any differences between climate forecasts and observations and claiming as a result that the forecasts have been “wrong”. Given these were forecasts decades in length, for the word “wrong” to be justified a large discrepancy between the forecast for a large part of the globe would need to be observed. In fact the differences have been relatively small and not widespread. The forecasts have in fact been very accurate.
The title is misleading, stating that “global warming” forecasts were wrong. In the article, it admits that the forecasts were for 0.13 degrees Celsius warming per decade, where it has actually been 0.12 degrees Celsius. I understand that originally the article stated that the forecast was for 0.2 degrees Celsius per decade, but has since been corrected. The headline made more sense with the original figure but now misleads.
The second sentence repeats the claim in more stark terms “world is not heating at the rate they claimed it was in a key report”. This is again misleading given the difference between forecasts and actual warming. The context of this line below the headline links the statement that forecasts were wrong with the rate of heating.The second paragraph states that the IPCC report “is understood to concede that the computer predictions for global warming and the effects of carbon emissions have been proved to be inaccurate”. The words “computer”, “prediction” and “predictions” do not appear in the report at all. There is no direct statement in the report to say that previous forecasts have been inaccurate.
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scaddenp at 08:08 AM on 24 October 2013It's waste heat
Can we recast these figures in watts?
Talking about change since 1750...
Waste heat would be 14E12 W (based on Flanner which does the full accounts)
I can't see how lightning isnt accounted for TOA loss, but is 2E10 W (total rather than change)
Since the top of atmosphere is cooling not heating due to increase in GHG, I cant see why losses from mass ejection would increase (OS thinks they would), but with an escape velocity of 10.8 km/s and about 3kg/s lost, total losses (not change since 1750) is of order E11 W
Change in energy at surface however since 1750 dues to increase in GHG is
1.4E15 W
No way to avoid the conclusion that waste heat is insignificant by comparison.
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Doug Bostrom at 04:45 AM on 24 October 2013Hurricane Sandy: Neither weather nor tide nor sea level can be legislated
A distant followup to this post. Here's a fine article in the New York Times describing how the New York City subway system was largely preserved during Sandy's passage and discussing future scenarios.
Could New York City Subways Survive Another Hurricane?
If you're not a NYT subscriber you can still read a limited number of articles per month. This article is worth the expenditure of a token.
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Doug Bostrom at 04:27 AM on 24 October 2013It's waste heat
Despite lightning's insignificance as an escape mechanism for energy, Tom's back of the envelope calculation for energy lost from Earth due to lightning is still fascinating.
One of the few consolations for ceasely stirring the AGW pot is seeing such interesting appreciations for the flow of eye-popping amounts of energy hither and thither. Yes, lightning isn't a big loss contributor but still the amount of power there is awesome.
Thanks, Tom.
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Tom Curtis at 03:43 AM on 24 October 2013It's waste heat
Despite the (as John Hart notes) excessive repetition in Old Sage's post that resulted in its being deleted, he does raise the interesting question of how much energy escapes to space due to lighting. I am unfamiliar with the literature on lightning, so the following estimate should be taken with a grain of salt. Never-the-less, the frequency of lightning strikes has been well surveyed (Christian et al, (2003) "Global distribution and frequency of lightning as observed from space by the optical transient detector"), with an upper limit of 50 flashes per second. That is significantly below traditional estimates if 100 flashes per second because (as it turns out) lightning is infrequent over oceans relative to its frequency over land, leading to ground based estimates being biased. The average energy release per lightning strike is 4 x 10^8 Joules. I believe much of that release is in terms of electrical transfer, and in the ionization of the air, rather than actual electromagnetic radiation. Further, most of the electromagnetic radiation will be absorbed on the Earth's surface or in the atmosphere. Never-the-less, I will use that value.
With the two values combined, it is easy to determine that the total global energy release by lightning averages 2 x 10^10 Joules per second, or 3.9 x 10^-5 W/m^2 averaged over the entire global surface. That represents just 0.14% of global waste heat from human use of energy, and hardly counts as a significant factor in the global energy balance.
Briefly, Old Sage also referred to radiation at very low frequency and ultralow frequency wave lengths. That radiation (except for that from lightning) is thermal radiation, and included in the energy calculations of the black body radiation of the Earth already.
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Doug Bostrom at 02:52 AM on 24 October 2013Fox News defends global warming false balance by denying the 97% consensus
I'd add another couple of characteristics to scientific denialism, if we consider Marlo Lewis as a phenotype of the denier in its natural environment:
-- Fabrication. Dana Nuccitelli is quite obviously not a "government-appointed expert" but Lewis is nonetheless completely uninhibited from embroidering truth with fiction.
-- Inability to distinguish science from public policy. "I disagree with policy so the science informing the policy must be wrong."
Regarding the latter, it's notionally a matter of personal choice whether to fasten one's safety belt, but the physics of plunging through a windshield remain a completely separate matter. Choice might be constrained by law which might be cause for resentment, but the physics of mass times velocity, conservation of energy, facial lacerations and skull fractures are still not public policy. This distinction seems entirely lost or absent in the minds of people such as Marlo Lewis.
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kanspaugh at 02:50 AM on 24 October 2013Fox News defends global warming false balance by denying the 97% consensus
Lewis probably used Deithelm and McKee's list of the five denialist characteristics in composing his opinion piece. "Hey, that's good stuff!"
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John Hartz at 02:36 AM on 24 October 2013It's waste heat
Old Sage: Your two most recent posts have been deleted for violating three prohibitions of the SkS Comment Policy, i.e., moderation complaint, sloganeering, and excessive repitition.
If you continue to violate the SKS Comment Policy, you will forfeit your ability to post comments on SkS articles.
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grindupBaker at 20:03 PM on 23 October 2013Why climate change contrarians owe us a (scientific) explanation
Tom #96: I disagree that "It will not with a dominant focus on OHC". I think any other way is a reverse description. I see it as: Radiative imbalance moves heat into oceans over long term. All the while it moves around the land & sea surface with complexity due to atmosphere and water in it. Land & sea surface must reach a higher temperature to balance and stop warming, it tries but the oceans keep stymying its efforts in rather jittery ways because ocean mixing isn't a smooth process. One day if the imbalance remains steady for long enough then the oceans will be ~85% sated and at ~85% and the surface temperature will finally rise to its new level (until the next big change in radiative balance).
Land surface flora & fauna will be battered by the surface temperature rise that is trying to stop the warming, but that's irrelevant to the Group I climate science. ENSO is currently the big repetitous example of "oceans keep stymying its efforts in rather jittery ways".
I contend that is the logical way to picture the physical processes. Incidental to it, I think the science is going to need the nuclear "half life" equivalent for ocean heat balance because I doubt the oceans have ever been 100% at balance with whatever is the surface temperature and never will be. I stand to be corrected but I see graphs depicting Greenland surface temperature shooting up & down during the glaciation. I've suggested above 85% of the balance point of the oceans with the surface temperature.
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Why climate change contrarians owe us a (scientific) explanation
When surface temperatures follow the forcing trend, they are in and of themselves a signicant part of the conversation, sufficient to carry the discussion. (Based, of course, on a reasonable view of the statistical uncertainty of short trends in the the presence of short term variations)
The rest of the climate has, of course, also followed the forcings including anthropogenic greenhouse gases, and warmed as well over the last 50 years or so. Currently, however, given a (short term) variation in surface temperatures, as well as quite likely some variations in the forcings - those variations are being used as rhetorical ammo by 'skeptics' who are less concerned with facts than with winning debating points.
And therefore those with a more global view are pointing out the rest of the climate, warming as it always has, to demonstrate that the short term variations in surface temperatures are indeed not evidence against the physics of the last 150 years. That doesn't mean the 'skeptic' tactic of cherry-picking short term variations makes sense.
If the 'skeptics' actually understood or valued measures of statistical certainty regarding air temperatures, it wouldn't be necessary to point to the rest of the climate. Meaning that their own lack of math is being used as another debating point. Shame on them.
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One Planet Only Forever at 13:25 PM on 23 October 2013Why trust climate models? It’s a matter of simple science
This is a nice capsule summary of modeling and why models are useful.
An added reason for the development of models is short-term forecasting to help decision makers understand their likely conditions for near-term things like farming, shipping, off-shore operations, and weather related disaster relief planning.
It is important to note that climate models cannot reliable forecast the significant but random or irregular impacts like major volcanic eruptions and the ENSO changes. The models can have these items as input from past history and reasonably produce the historic results, but the models cannot reasonably forecast these impacts. However, these impacts are not "drivers" of long term change. So the models can reliably forecast the "norm" into the future with the understanding that random factors like major volcanic eruptions and ENSO changes will create departures from the norm.
The models are reliable even when they do not predict the long-term ENSO influence, because they are not able to predict the ENSO far into the future so they don't try to. However, as more is learned about the intricate behaviour of the ocean currents the models will be able to include reasonable long-term predictions of ENSO.
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Doug Bostrom at 09:44 AM on 23 October 2013Why climate change contrarians owe us a (scientific) explanation
I should add that if we really do think we're seeing a slowdown in warming that is not caused by ocean dynamics then we can all kick our heels for joy and stop discussing anthropogenic global warming right now.
The alternative explanation to the ocean would seem to presuppose that radiative imbalances can come and go according to principles that entirely elude us. That doesn't seem likely, not at this juncture.
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Doug Bostrom at 09:39 AM on 23 October 2013Why climate change contrarians owe us a (scientific) explanation
It doesn't count for much (anything, actually) in the grand scheme of things but some of us (me, for instance) have always been bothered about our myopic focus on surface warming. Well, I say "always" but by that I mean since the moment the massively-obvious-in-hindsight disparity between ocean thermal capacity and that of the air was pointed out to me. I became interested in the climate change topic somewhere around 2005 and it was shortly thereafter that it became apparent most of the action was going to be in the watery part of the Earth, indeed that most of the dynamics even in the air were going to involve water and phase transitions of various kinds.
The gaseous atmosphere is like a cartoon character grappling onto the wheel of a wagon, battered and pummeled by something much more energetic. The faster the wagon goes, the worse the beating, punctuated by coincidental moments of relative peace. The wheel is the surface of the ocean and wagon it's attached to is the bulk of the water.
Tom's right that a really extended period of not much happening in the wee gassy part of Earth would be a cause to reexamine assumptions. Though Tom is much more scrupulously connected to the details and thus better able to say, for my part I'm not sure even then we'd be looking at a fundamental collapse of the concept of AGW. The system we're in is being shocked in a novel way; how the dynamics of this thing unfold is something we can roughly predict but it's clear that some biggish details elude us, as evidenced by the (sorry to mention it yet again) Arctic sea ice scenario.
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DSL at 07:46 AM on 23 October 2013Why climate change contrarians owe us a (scientific) explanation
Tom, I see what you're saying. I get it, and perhaps I'm pulling an "if by whiskey," but when I say "AGW," I mean the greenhouse effect enhanced by humans digging up carbon and burning it, and by humans directly altering the biosphere. I don't mean "a positive trend in GMST." I mean a trend above what we would expect from natural forcings. If you had that 50 year plunge, how high on the list of things to check would the enhanced greenhouse effect be?
When I discuss this issue with the general public, and especially with doubters, it's clear that in their minds, "global warming" means a positive trend in GMST, and that if there is no trend in GMST, climate scientists are 1) engaged in fraud and/or 2) don't know what they're talking about. Of course, neither condition is true, even if GMST is flat over the short term. In other words, I'm not working this over for the sake of being absolutely precise; I'm working it over in order to find the best way to start a productive engagement with members of the general public. One of the ideas I want to de-bunk is the idea that GMST != "global warming." Even if it's technically true, it's not a healthy place to work from. Svante Arrhenius expected the enhanced greenhouse effect to play out in GMST, but he didn't use GMST as a starting point for the theory.
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vrooomie at 07:06 AM on 23 October 20132013 SkS Weekly Digest #42
Doug, I second John's suggestion...a spiffy blog post is in the making, with what you've posted, and your considerable gift of elucidation.
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Tom Curtis at 06:45 AM on 23 October 2013Why climate change contrarians owe us a (scientific) explanation
DSL @95, climate scientists have used rising GMST as evidence of global warming. An example is Meehl's analysis of temperature record ratios, and multiple other examples could be found. Further, if the temperatures were to plunge for long enough it would falsify AGW. IF, for example, temperatures were to plunge (trend less than -0.1 C per decade) for the next five years despite a series of strong El Ninos, a lack of volcanoes, and strongly rising anthropogenic forcings, I think AGW would be falsified for practical purposes. No theory is ever completely falsified, in that new data and new understandings of old data can rescue the most moribund theory in principle; but in the above scenario the likilihood of AGW being rescued would be small IMO.
Given the reliance of climate scientists onincreased global temperatures as evidence of AGW, there is some justice in claims that defenders of climate science have shifted the goal posts in response to the so-called "hiatus". As a result, I do not like discussions of the "hiatus" that focus exclusively, or almost exclusively on OHC. Of course, the shift of focus is not an ad hoc response to criticism. It is justified by the theory, and partly driven by the availability of better OHC data. Further, the climate scientists never relied solely, or even mostly, on rising GMST as evidence of AGW. The so-called "hiatus" has forced climate scientists (and defenders of climate science) to provide a better, more nuanced account of AGW - or at least it should. (It will not with a dominant focus on OHC.) That is a good thing. However, reasonable observers will note that the shift in focus merely results in defenders of climate science discussing in more detail features of the theory that have existed all along.
I have some concerns about SkS coverage of the "hiatus" on the basis of an excessive focus on OHC, and an insufficient focus factors which would have caused a decrease in GMST absent AGW. That is, I would like to see a little more focus on ENSO, and declines in forcings from other sources, and slightly less focus on OHC. Such a shift would, IMO, give a more balanced opinion.
Your post @90, however, goes to far in leaving temperatures out of the equation. I plunging global temperature for 50 years not falsifying AGW? Really? Not without the most extraordinary circumstances. Given that a grand solar minimum equivalent to the Maunder Minimum would only cause an (from memory) 15 year hiatus in temperature increases, the extent of volcanism, asteroid impact, or decreased solar activity required for falling GMST for 50 years and AGW being true will constitute a catastrophist nightmare in its own right.
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scaddenp at 06:22 AM on 23 October 2013It's waste heat
I'll try and be more specific. If you take a textbook example and say ask how much will body increase in temperature if you add x extra joules to it, then looking at heat capacity is certainly the way to go. But that is not the relevant equation, because you are ignoring energy transfer out of the system. The text book is fine but you have to read all the chapters. You appear to have read the chapters on conductive heat transfer and missed the one on radiative transfer.
Perhaps
Principles of Heat Transfer, Kreith (1965) or
Fundamentals of Heat and Mass Transfer, Incropera and DeWitt (2007) for more modern.
Or if you are more my age, then
Heat and Mass Transfer, by Eckert and Drake (1959)
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Bob Lacatena at 01:49 AM on 23 October 2013Does the global warming 'pause' mean what you think it means?
Dean @16,
But if the climate system even accumulated more heat during the "pause"... how can this be consistent with the IPCC assessment update, including a fair chance (17%) of sensitivity being even <1.5?
The simple answer is that if the deep ocean is, in effect, able to act as a bottomless sink for at least some of the heat, then the system is able to absorb more energy with less change in atmospheric temperatures, thus effectively reducing climate sensitivity (same forcing, less actual temperature change).
The more complex answer is that the basic, accepted equation for computing Effective Climate Sensitivity based on short term observations is:
ECS = F2x•∆T / [ ∆F – ∆Q ] : Forster and Gregory, 2006
where ECS is the Effective Climate Sensitivity, F2x is the forcing due to a doubling of CO2, ∆T is the observed change in temperature of the period, ∆F is the observed or estimated/computed change in forcing over the period, and ∆Q is the observed change in heat content of the entire system (atmosphere plus oceans plus land plus ice melt).
When applying a reduced observed temperature of the past 30 years with a monotonic heat gain over the same time period, the net result is a lower sensitivity.
Of course, all of this assumes that the short tail of the pause is significant, i.e. that it is reflective of the longer term trend, so that the 30 year period of observations is indicative of what is to come.
Alternately, we might see a "rebound" effect from the deep ocean warming, much as we saw following the Pinatubo eruption, where temperatures climb dramatically. We could also see a double-rebound effect if that is combined with a less-quiet sun, a reduction in dimming aerosols, and less preponderance of La Niña events. In that event temperatures, and a newer, revised estimate of climate sensitivity, would sky rocket.
But for now, when considered with the full body of evidence and the variety of methods of computing climate sensitivity, the observational method points to at least a lowering of the lower bound of the expected range of climate sensitivity.
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DSL at 01:08 AM on 23 October 2013Why climate change contrarians owe us a (scientific) explanation
Tom, have "climate scientists used GMST as evidence of global warming"? You're pointing out that surface temp is critical to understanding the results of the initial forcing, but an increase in GMST is not evidence for the existence of the initial forcing (the human-enhanced greenhouse effect). Again, if surface temp were plunging, would it falsify AGW? No. But claiming that GMST is evidence of global warming allows a plunging surface temp to be read as a falsification of AGW.
I could also point out that the increase in RF via enhanced GHE did not occur in a vacuum. It developed dynamically with existing ocean energy conditions. Surface temp is also a function of OHC and ocean circulation, and vice versa.
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Phil L at 00:44 AM on 23 October 20132013 SkS Weekly News Roundup #42B
Meanwhile more and more petroleum products are being shipped by rail. Another derailment in Alberta is burning out of control. Luckily this most recent derailment one wasn't in an urban area like the recent disastrous derailment in Lac-Mégantic, Quebec. The energy spent railing against this pipeline would be better spent pushing for a fee and divadend on carbon.
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John Hartz at 00:38 AM on 23 October 2013It's waste heat
Old Sage:
Please note that posting comments here at SkS is a privilege, not a right. This privilege can be rescinded if the posting individual treats adherence to the Comments Policy as optional, rather than the mandatory condition of participating in this online forum.
Please take the time to review the policy and ensure future comments are in full compliance with it. Thanks for your understanding and compliance in this matter.
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Dikran Marsupial at 00:19 AM on 23 October 2013It's waste heat
Old Sage wrote "I am puzzled by the fact that I am not aware of anyone who says that 250ppm or 450 ppm of CO2 is the cause of warming has put it in the context of the concentration required to render the atmosphere totally opaque."
AFAICS, you appear to be labouring over a fundamental misunderstanding of the mechanism underpinning the enhanced greenhouse effect. The absoption of IR emitted from the surface by CO2 is a red-herring; what matters is the temperature of the layer in the atmosphere from which IR can escape without being absorbed by the CO2. See this RealClimate article by Spencer Weart and Raymond Pierrehumbert.
"The only reason I can see for pinning warming on CO2 is that it is increasing and is a useful parameter for sticking in a model, well"
Well perhaps you should read up on the basic mechanism of the EGHE before making pronouncements. The basic mechansim was set out quite clearly by Gilbert Plass in the 1950s. You are unlikely to convince anybody with your theories until you can show that you have at least read up on the basics of the mainstream scientific understanding of climate change.
Moderator Response:[JH] I deleteed Old Sage's most recent post because it was sloganeering. I am letting this comment stand because it accurately quotes statements made by Old Sage in his post. Other repsonses to Old Sage's post will be deleted.
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John Hartz at 23:20 PM on 22 October 20132013 SkS Weekly Digest #42
Doug:
Perhaps you could channel your musings into a blog post article. As fate would have it, Dana is on a two week vacation in Australia. We therefore need other authors to step up to the plate and knock it our of the park. (World Series time in the US.)
I'm watching CNN. It just reported on the wildfires. Quoted an offical who said, "As bad as it gets!"
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chriskoz at 17:15 PM on 22 October 20132013 SkS Weekly Digest #42
doug_bostrom,
I chipin to your conversation.
The factors that contribute bushfires in AU are not only the record high temperatures (as proven in your last post) but also:
- large amout of burnable biomass in scherophyl forests
- dry conditions
- wind
The last factor is unpredictable (weather) but the first two are changing with changing climate. In particular, recent studies concluded the intensification of LaNina/ElNino cycles on E coast; means more intense LaNina floods and drier/hotter ElNino. This is exactly what we've experienced in last few years: remember record floods of 2010-2011 which even contributed to the unusual sea level negative departure from the satellite treands by 7mm? I've been watching the rainfall data in the fire affected area (Blackheath NSW where I own the house which is now under threat to burn) during that time. The rainfall anomally was high (some twice as much fell) and summers mild, contributing to the high understory growth. Then came the record dry spring - the driest in my memory - only some 70mm fell in 3 and half mounts to date. Did ElNino return? To my feeling it did! But if the ENSO index is globally neutral yet, what would happen if the index becomes truly positive?
I saw some comments "bushfires have always been part of AU life and cliame change has nothing to do with it" (ala "climate has always been changing" argument) but the silly commenters don't understand that ENSO fluctiations are driving the bushfire conditions and that said fluctuations are predicted to intensify. And what we're seing today is the result of such intensification. And remember, this is just the pre-season (the begin of official suthern summer is still 2 month away), it can only become worse next time, if such conditions align in the middle of summer...
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Doug Bostrom at 16:16 PM on 22 October 20132013 SkS Weekly Digest #42
Carrying on my conversation with myself, it strikes me that this year's early and large fire situation in Australia is roughly akin to what hurricane Sandy was to the US, except perhaps more so. We have:
-- Historically hottest September on record for Australia, following...
-- Australia's warmest winter on record, which came after...
-- Australia's hottest summer on record, as part of...
-- Australia's warmest 12 months on record, which contained...
-- Australia's warmest day, week and month on record, appearing likely to lead to...
-- Australia's warmest calendar year on record.
Yet when I look at comments attached to the Figueres article above, I see familiar, confidently expressed opinions that this year's fire situation in Australia is quite normal, nothing out of the ordinary, to be expected, and most of all definitely not connected with climate.
Really not climate, for sure? But the climate -has- changed:
So how can people say with such certainty that this year's unusually large, early and dynamic fires have no relationship with climate? Last year's fires occurred in the context of warm and dry conditions, something everybody agrees encourages fires. This year's fires are happening in similar context. If we see year-on-year increases in fire activity and those years are accompanied by atmospheric changes that are larger than weather and these changes tend to encourage fires, then what's a reasonable, consistent explanation for how these fires are unconnected with climate?
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Tom Curtis at 16:15 PM on 22 October 2013Why climate change contrarians owe us a (scientific) explanation
DSL @90, of the theory of the greenhouse effect can be summed up in a single equation, that equation is:
ΔT=(ΔF-ΔQ)/λ
where ΔT is the change in Global Mean Surface Temperature, ΔF is the change in forcing, ΔQ is the change in global surface heat content (of which approx 90% is OHC), and λ is the climate sensitivity factor.
Consequently GMST is integral to understanding the greenhouse effect, and to predicting the consequences of a change in greenhouse gas concentration. That does not mean GMST can be understood in isolation. ΔQ is also essential to understanding the theory, and any body claiming the so-called "hiatus" disproves AGW has forgotten that; but we should not go overboard and ignore the central role of surface temperature in the theory. Afterall, the upward IR flux is a function of surface temperature, not of OHC.
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grindupBaker at 15:48 PM on 22 October 2013Why climate change contrarians owe us a (scientific) explanation
@Andrew7x8 #89 I agree with your point but there's no progress without change so suggest you attempt to explain that GMST is a pretty good proxy for climate warming & cooling when comparing blocks of at least 30 years with other ones and it's all we have for comparison from 650,000,000 until ~100 years ago, but we are finally starting to get the real deal, ocean heat, measured well and we can increasingly expect that to be the quantity measure this century because it's going to be a true measure even from one year to the next. Point out that it makes the topic interesting because if GMST were to soar +0.5C next year with no identified cause from insolation, albedo, aerosols or greenhouse gas change then people could correctly say "well, it's hotter than hell but at least global warming has completely stopped for now" right ? If Arctic icebergs discharged into the Atlantic increased, they'd cool some Atlantic surface water, reduce surface temperature and increase global warming. Fascinating.
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scaddenp at 14:08 PM on 22 October 2013Why climate change contrarians owe us a (scientific) explanation
Well I think Andrew does have point. GMST is where we live so that is what we notice. However, if you are going to have people claiming climate science is wrong because GMST is rising more slowly, then you do need to look at bit further afield than just the very noisy GMST. However, until we got Argo in 2002, ocean temperatures estimates had large error bands especially below 700m.
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DSL at 13:18 PM on 22 October 2013Why climate change contrarians owe us a (scientific) explanation
Andrew, further, and again, 90%+ of the effective thermal capacity of the climate system is wrapped up in the oceans. Another 2-3% is in global ice mass loss. Using surface temperature to assess global warming is like writing a review of a restaurant based on drinking a glass of water and eating one appetizer. Can doing that tell you something about the restaurant? Absolutely, but you'd never actually write the review based on just the appetizer.
I hope.
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DSL at 13:14 PM on 22 October 2013Why climate change contrarians owe us a (scientific) explanation
No, Andrew. The theory of anthropogenic global warming (AGW) is not based on any surface temp record. It is simply the greenhouse effect plus the proposition that humans are responsible for the recent rapid rise in atmospheric CO2.
Even if the surface temp were plunging negative for 50 years, the theory would still be in evidence. It would simply be colder without AGW.
You need to make a distinction between the theory of anthropogenic global warming and modeling of future elements of climate. That distinction has always existed in the science. AGW is not based on the output of general circulation modeling.
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michael sweet at 12:10 PM on 22 October 2013It's waste heat
Ols "Sage" has yet to supply a single reference supporting his absurd claims about heat in the atmosphere. He is sloganeering and should be required to support his position to continue posting. He is completely ignorant about heat transfer and he refuses to read the informed posts that Tom has, again, made for him.
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Andrew7x8 at 12:04 PM on 22 October 2013Why climate change contrarians owe us a (scientific) explanation
I read "The history of climate science" and "The Big Picture", as scaddenp suggested.
I noticed that the first sentence of "The Earth is Warming" in "The Big Picture" is:
The Earth is Warming
We know the planet is warming from surface temperature stations and satellites measuring the temperature of the Earth's surface and lower atmosphere.Surely the public and mainstream media are focused on GMST, because climate scientists used GMST as evidence of global warming. It is unfair to blame the public and mainstream media if the "goalposts" are moved.
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scaddenp at 09:15 AM on 22 October 2013It's waste heat
And a further note - in addition to an atmosphere that doesnt radiate, old sage's calculation requires that somehow waste heat cant warm the ocean (the upper 2.5m having same heat capacity as entire atmosphere).
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Doug Bostrom at 08:29 AM on 22 October 20132013 SkS Weekly Digest #42
Chief UN climate herder Figueres makes a radical proposition: yes, climate politics, climate policy and climate outcomes are connected.
UN climate chief Christiana Figueres calls for global action amid NSW bushfires
Of course she'll be denounced as rude and insensitive. It's sort of the global equivalent of the 2nd Amendment discussion.
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