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Comments 41301 to 41350:
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Michael.M at 05:11 AM on 21 October 2013Does the global warming 'pause' mean what you think it means?
Vroomi, yes, I also have the problem with the tingly anntennas....
Dean, you may have a problem regarding uncertainty: There is a likelihood, that the equilibrium sensitivity is as low or lower than 1.5 - but you forget that uncertainty is not or friend! Because there ist just (or nearly) the same chance, that the equilibrium sensitivity is as high or higher than 4.5°C. On my part the best message in the whole sensitivity discussion ist that it is very unlikely to be higher than 6 degrees. (Judith Curry once, pushing uncertainties as always, claimed the ES may be up to 10 degrees .... that was the scariest "argument" I ever heard, let alone from a "sceptic")
A discussion to ES, in german: IPCC 5 - Uneinigkeit zur Klimasensitivität
Discussion with AR5 , graphs pages 172(ES) and 173(TS)
PS: Dana, with your Enigo Montoya reference you made my day! :-D -
Dean at 04:41 AM on 21 October 2013Does the global warming 'pause' mean what you think it means?
vrooomie and Matt, I don't think that there is anything particularly wrong with main stream climate science and I respect the IPCC reports as goldmines of scientific information. But I have spent a fair amount of time arguing with "skeptics" and would like to have a consistent understanding of the current state of knowledge.
As I wrote, I cannot reconcile the lowered equilibrium sensitivity (lower end) with Dana's explanations about the "pause", At least one expert has claimed: "The lowering is based on one narrow line of evidence: the slowing of surface warming during the past decade".
But if the "pause" has nothing to do with weaker feedback mechanisms, this a contradiction. Larger natural variations even points to stronger positive feedbacks.
Reading through the report there is quite a lot of mentioning about the period 1998-2012. But there is no systematic scientific reason for this, it is cherry-picking. As a non-expert I don't really want to claim that the IPCC authors are wrong, but lets say I'm rather skeptical against some of their assessments and would like to have confirmation that the lowering wasn't just due to the massmedia/politically driven pressure.
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John Hartz at 02:55 AM on 21 October 2013IPCC model global warming projections have done much better than you think
@VeryTallGuy #112:
Also keep in mind that non-scientists had a hand in crafting the final wording of the WG1 summary report.
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vrooomie at 02:08 AM on 21 October 2013Does the global warming 'pause' mean what you think it means?
"Was he not just asking that, given the ocean's ever-increasing heat content (as per the article) and despite the cool sun/La Nina dominance slowing surface temps very little, how could the IPCC possibly extend the lower bound of projected ECS down to 1.5degC? "
Not sure, and it's why I asked. As a long-time veteran of seeing deniers creep into conversations here and across the Web--and I am NOT asserting Dean is one--I have 'tingly antennae' about curious questions like that, ergo, why I asked, Dean hopefully will lean in and elucidate further on his intent, and I'm happy to hear it out.
Remember that the IPCC bases it reports on the severe side of 'least drama,' given the makeup of its constituent membership: their downgrading CS may or may be a function of that, or, perhaps more likely, is a function of science doing as it always does, and should: consider ALL rational, data-driven conclusions.
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Matt Bennett at 22:09 PM on 20 October 2013Does the global warming 'pause' mean what you think it means?
vrooomie,I'm sure he'll correct me if I'm wrong but I didn't read the second part of Dean's post as questioning the science, as you appear to have potentially identified it?... Was he not just asking that, given the ocean's ever-increasing heat content (as per the article) and despite the cool sun/La Nina dominance slowing surface temps very little, how could the IPCC possibly extend the lower bound of projected ECS down to 1.5degC? Oncologists aside, doesn't he agree with you that this seems an unlikely scenario? -
Doug Bostrom at 05:23 AM on 20 October 20132013 SkS Weekly News Roundup #42B
jyushchyshyn, it's a sad fact that human nature dictates we respond better in aggregate to price signals than common sense. Of course you're technically speaking correct in saying we can solve this problem by ending demand for hydrocarbons as fuel, but in reality we won't do so without encouragement in the form of our wallets deflating more quickly.
Let alone the awesomely nasty nature of Canada's own Mordor, each and every source of petroleum that is removed from our imperfect accounting system helps to contribute a little bit to our price signaling.
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jyushchyshyn at 03:54 AM on 20 October 20132013 SkS Weekly News Roundup #42B
re Canada’s efforts accelerate a global tragedy of the climate commons
Let's stop one pipeline and call the problem of global warming solved, and continue to burn coal, drive SUVs and import OPEC oil.
If you want to stop new pipelines from being built, cut them off at the source. Switch to the new energy sources and there will be no demand for the oil which new pipelines would deliver.
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vrooomie at 02:31 AM on 20 October 2013Does the global warming 'pause' mean what you think it means?
Dean, not sure how to answer your question at 16, but your post certainly does raise my antennae..suppose a team of *extremely* well-educated experts in a given field--say, oncologists--have studied my files, data, and extensive and comprehensive collection of CT scans and arrives at an opinion--a consensus, if you will--of my having an 83% chance of dying from an aggressive cancer.
How would it be rational, for me, to exclaim, "Well, shootfire, boys! That means I have a fair 17% chance of all of you, being wrong!" I'm asking the question because the final part of your post made me twig at the rest. would it be rational for me to proceed with the experts' 83% estimate of my mortality, or to run with the slim chance that 17% of them felt there was no worry?
I am sure the brainiacs among the SkS team can certainly address the first part of your post, and I am also interested in that, given how bad I am at stats.
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Dikran Marsupial at 00:39 AM on 20 October 2013IPCC model global warming projections have done much better than you think
Conventional statistical regression cannot be used to make reliable caual inferences as they are based on correllations, and correllation is not causation. They can be use to show that X can explain Y, but we cannot say that X does explain Y as there may be some other cause that is not represented in the model, or there may be confounding variables, etc. If this were not the case, we could regress GMSTs on the surface area of ladies undergarments and conclude that CO2 does not cause climate change
Underwear (to some extent) can explain global warming, but that does not mean that to any extend underwear does cause global warming. Likewise, the fact that including ENSO in a regression model add explanatory power, that does not mean that ENSO is the cause of the variability it explains.
The use of models similarly shows that ENSO can explain the variability in GMSTs, but it doesn't establish that it actually has caused the hiatus. The reason it does not is because we cannot be absolutely sure that it explains it for the right reason (note constraining SSTs means that the transfer of energy between the air and ocean does not obey the laws of physics correctly).
Now the fact that we cannot obtain certain knowledge from observations means that in practice we need to use other criterion, such as theory, to arrive at the best explanation of the data. Thus I have no problem at all if someone finds the regression models sufficiently convincing to be sure that ENSO is the cause of the hiatus (which is actually fairly close to my position - I'm pretty confident that it is just ENSO), but the regression model itself does not establish a causal link.
VeryTallGuy - generally the IPCCs comments are well thought through, provided they are interpreted as clear statements of the scientific position, expressed by scientists who know the issues well, intended as statements for the record. They are not however generally well worded as statements intended to resolve misunderstandings in the blog debate on climate, nor are they expressed in terms that prevent any possibly (even willfull) misunderstanding. I think the IPCC are doing the right thing in expressing the science in a manner designed for a primarily scientific audience.
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Paul Pukite at 00:02 AM on 20 October 2013Why Curry, McIntyre, and Co. are Still Wrong about IPCC Climate Model Accuracy
Tom Curtis,
Healthy skepticism is warranted. I have more info here on the general approach:
http://contextearth.com/2013/10/04/climate-variability-and-inferring-global-warming/
The October 1943 spike is the single anthro effect I added apart from CO2. You can turn that off by checking off anthro aerosols. I added that because since the overall agreement is so good, one can really start to look at particular points in time for further evaluation.
All the lags can be modified by the user. You can turn all of them off by setting the lags to zero. The agreement is still good.
The application of the LOD (length of day) is crucial as a proxy for multidecadal oscillations. This ensures conservation of energy and conservation of momentum according to work by Dickey et al at NASA JPL [1]. The fluctuations in kinetic energy have to go somewhere and of course changes in temperature are one place for this dissipation.
As far as volcanic disturbances, I took the significant ones from the BEST spreadsheet of Muller. If you can point me to the volcanic fording data from GISS, I can use that instead. Thanks !
[1] J. O. Dickey, S. L. Marcus, and O. de Viron, “Air Temperature and Anthropogenic Forcing: Insights from the Solid Earth,” Journal of Climate, vol. 24, no. 2, pp. 569–574, 2011.
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Dean at 22:57 PM on 19 October 2013Does the global warming 'pause' mean what you think it means?
There is one thing that I don't understand. It said that the IPCC lowered their likely equilibrium sensitivity interval from 2-4.5 to 1.5-4.5 due to the "pause" (or rather due to simplified models that were very sensible to this kind of short term variability). Independent paleo data, GCM:s and observations of feedbacks does not support any (likely) values <2.
But if the climate system even accumulated more heat during the "pause", as claimed in the blog post, despite weaker sun and (probably) stronger negative aeorosol forcing, how can this be consistent with the IPCC assessment update, including a fair chance (17%) of sensitivity being even <1.5?
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VeryTallGuy at 17:29 PM on 19 October 2013IPCC model global warming projections have done much better than you think
Dikran, Tom,
thanks for the perspectives, very interesting and appreciated. I must admit, compared to much of the IPCC output the bit on the "hiatus" comes across as not particularly well thought through. -
Doug Bostrom at 14:39 PM on 19 October 20132013 SkS Weekly News Roundup #42B
Re the mess caused by the shutdown, I'd like to see a clearinghouse set up for researchers to describe the impact on their work.
I know of a major meeting here in Seattle to do with earthquake resilience that was thrown into chaos thanks to the GOP's psychotic clown posse. Researchers coming in from New Zealand and other places at great expense arrived to find that their USGS counterparts could technically face fine and imprisonment* for meeting as agreed, ages ago. Not only were we wasting our own time but that of others. We're also destroying our credibility as reliable partners.
Other people I know faced similar absurd problems. Seeing all of this waste summarized in one place would be helpful and instructive.
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bwilson4web at 13:53 PM on 19 October 2013Does the global warming 'pause' mean what you think it means?
Maybe I missed it but claiming something about a change in the slope of global warming is nonsense. Now if the sign of the slope changed, I'd be interested but to quibble about the value of the slope?
The honorable global warming deniers are face with some hard, undenible facts. Arctic shipping through the NorthEast and NorthWest passage exceeded 1 million tons in 2013. It was 1.2 million tons in 2012 and similar numbers of ships, tonnage unknown, in 2011. The practical effect, the business effect, is Arctic shipping is open for the third year in a row.
So if this is just a slope problem and not a sign, hammer them away with "Is it cooling now?"
Bob Wilson
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Manwichstick at 12:54 PM on 19 October 2013Does the global warming 'pause' mean what you think it means?
I just rebutted a piece by a local TV meteorologist here in Toronto, and I used an "office building analogy" to explain the pause in global warming.
See what you think of it. I'm wondering if I subconciously "borrowed" it from someone here at SKS...
The scientists understand how “temperature” is not the same thing as “heat”. They have a good understanding of how surface temperatures are coupled to global heat content and how ocean currents affect surface temperatures. Farnell’s point is false because surface temperatures can drop while the Earth still warms (over short time periods). The folly of point 1) can be illustrated with this example:
Imagine an office building with 10 floors. Now picture yourself sitting on the 10th floor of the building and making this claim,
“No one must be entering this building since the number of people on the 10th floor has not gone up.”
Imagine making that statement above while simultaneously looking out the window and noticing the number of people entering the building is greater than the number of people leaving the building. Point 1) is like that. Its conclusion does not follow from its premise, and it is observably wrong. -
gws at 09:07 AM on 19 October 2013Does the global warming 'pause' mean what you think it means?
caroza @12
hmmh, an analogy may be a bedroom: the person in bed is the heat source, the blanket the top layer of the ocean, the air in the room all deeper layers; the bedroom is thermally well insolated. Findings, with heat source constant:
- the blanket heats up quickly but then stays at equilibrium Temp., the air in the room will heat up more slowly over time although the blanket does not change Temp. any more
- if you shake out the blanket regularly (ENSO), then put it back in place, it will cool a little temporarily while the room keeps heating
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Tom Curtis at 07:26 AM on 19 October 2013IPCC model global warming projections have done much better than you think
VeryTallGuy, first (and with all respect), Dikran Marsupial has misinterpreted me. I do say that ENSO is the dominant cause of the "hiatus" (better, slowdown), not that it could explain it. Of course, it is always possible that I am over interpreting the evidence, and that Dikran's claim is more accurate given the evidence. That would be the case if global warming would have accelerated absent all factors contributing to the slowdown. In that case, the contribution of ENSO could be sufficient to almost completely explain the reduction in short term observed trend relative to the long term observed trend, but changes of forcings could likewise explain a similar amount. In that case, temperatures without these short term influences would have accelerated to an approx 0.25 C per decade warming trend.
With respect to my actual claim, however, it is not inconsistent with that in the IPCC. To be specific, my claim is that, when compared to all other individual factors influencing the slow down in global temperature rise, ENSO has a significantly larger influence than any other individual factor; and that the influence of ENSO is not much smaller (if smaller at all) then the sum of all other factors. That is what is mean by "dominant". In contrast, the IPCC claims that the sum of the influence of natural variability is not much different from the sum of the influence of changes in forcing. Thus, there may exist natural variability of opposite sign to the ENSO influence, reducing the net impact of natural variability relative to the net impact of changes of forcings. Or the influence of ENSO based natural variability may be greater than the combined influence of changes in forcing, with the two individual factors contributing to change in forcing each individually being significantly smaller than the ENSO influence. In both these cases, both my claim and that of the IPCC would be correct.
A third possibility is that the IPCC understates the influence of natural variability. Given that the IPCC did not have access to Kosaka and Xie (published online in late Aug 2013, and not included in the IPCC references), that is plausible. Equally plausibly, a new study may come out showing Kosaka and Xie's result to not be reproducible, or to have overstated the influence of ENSO (in which case my opinion would revise back towards that of Dikran Marsupial and the IPCC).
So, to summarize:
1) My claim, which assumes a linear base trend in global temperatures, may be incorrect and the IPCC's correct because global temperatures would have shown an accelerating trend absent both the ENSO influence and the reduced forcings;
2) We could both be correct, with the ENSO influence on the lower end of what I expect based on the evidence but still the dominant influence (ie, greater than 50% and >> than any other individual influence);
3) Either I or the IPCC could be wrong, they because they present a snapshot of the science as it existed 6 months ago; or I because the most recent evidence (on which I rely) is overstated in some way.
Finally, I note that the IPCC discuss the influence of the PDO rather than ENSO. That is not a difference between us in that the two are closely related, with PDO states causing dominant influences of La Nina or El Nino (depending on whether the PDO is +ve or -ve) in ENSO; or because the PDO is just a filtered effect of ENSO on the north Pacific. (SFAIK, it is not as yet clear which of these is the case.)
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Tom Curtis at 06:38 AM on 19 October 2013Why Curry, McIntyre, and Co. are Still Wrong about IPCC Climate Model Accuracy
WebHubTelescope @190, can you direct me to documentation justifying the SALT model method, because on a casual perusal I am far from impressed.
My initial concerns were raised by the tunable, and different lags for different forcings. If you allow yourself to tune lags, I am sure you can get some very good fits between models and observations, but a physical explanation as to why solar forcings should have half the lag of anthropogenic forcings, and nearly one sixth that of volcanic forcings is decidedly lacking.
On closer inspection, I am even more perplexed. The "fluctuation components" show a very large, unexplained "linear" adjustment peaking at 0.396 in Nov 1943, and apart for its rapid fall off, is essentially zero at all other times. That is by far the largest single fluctuation value on the chart, and has no apparent physical basis. The lod adjustment is also unexplained (what does lod stand for?) and is certainly not a component of the GISS model forcings. Further, the volcanic "fluctuation component" does not match the GISS model forcings from the 1920s to 1940s.
Without documentation, it appears from the "fluctuation components" chart that arbitrary "fluctuations" are added as necessary to ensure a fit between model and observations. If so, we should be less than impressed that a fit is then found.
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caroza at 05:41 AM on 19 October 2013Does the global warming 'pause' mean what you think it means?
dana @ #5, would it make sense that as the oceans warm overall, upper layers might cool? I remember reading years ago (can't remember where, sorry) that as the ocean warms it mixes better and becomes less stratified. I assume that's still true although I don't know what sort of temperature increment results in what sort of degree of mixing. But it occurred to me at the time that as the deeper ocean warmed, if it mixed better with the layer above 2000m then that might cool the upper layer (for a while), given that the volume of water below 2000m is so huge by comparison to the thin upper layer, and relatively cold, so a tendency in the direction of thermal equilibrium might reduce upper layer temperatures.. Is that a possibility? Sort of analogous to the weakening jet stream resulting in weather which is warm by Arctic standards but very cold by British or European standards dumping snow and ice all over Britain and Scotland and making the deniers happy because of the snow in their back garden.
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Doug Bostrom at 05:38 AM on 19 October 2013Does the global warming 'pause' mean what you think it means?
Sou at Hot Whopper has posted a pleasingly concise explanation of the major fallacy of Bob Tisdale's attempt to reply to Dana:
Bob Tisdale rejects the greenhouse effect
The seemingly rude title of the piece is unavoidable due to Tisdale's conclusions; the title is not impolite but is neutrally descriptive of the logical box Tisdale has constructed around himself.
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ajki at 04:17 AM on 19 October 2013IPCC model global warming projections have done much better than you think
Perhaps the best way of showing the effect of removing *some* of the more or less known "internal variables" is... well, show it:
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Paul Pukite at 04:11 AM on 19 October 2013Why Curry, McIntyre, and Co. are Still Wrong about IPCC Climate Model Accuracy
For SteathGuy, I would recommend looking at energy balance models first. Go over to this web site that generates model-based fits to various temperature series and intereract with the graphs:
http://entroplet.com/context_salt_model/navigate
I spend too much time at Curry's site tryin to reason with the skeptics and I at least give you credit for trying to construct a somewhat methodical argument. I just suggest that instead of looking at the GCMs at first, that you try to pull apart the possible independent factors that give rise to subdecadal and decadal climate variability. The snaphot below is a view of an interface that you can play with and see how the various lags have an effect on volcanic disturbances, TSI, etc.
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Alpinist at 02:03 AM on 19 October 2013Does the global warming 'pause' mean what you think it means?
Here's Tamino's take on one of Tisdale's recent posts:
http://tamino.wordpress.com/2013/10/05/bob-tisdale-pisses-on-leg-claims-its-raining/
Moderator Response:[Sph] This is a borderline violation of the Comments Policy (no links without context). As it clearly relates directly to an analysis of Tisdale it is applicable (although, too, the whole Tisdale thing is in in danger of wandering off-topic), but in the future, please provide your own (better clarified) context around such a link.
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Does the global warming 'pause' mean what you think it means?
garethman - That's a very good point, rhetorically "plausible" often has little connection with "likely" or "reasonable". Folks like Monckton make it a way of life, sounding entirely plausible while under closer examination what they are saying is utter nonsense. (Sounds great - just don't think about it...)
General items that jumped out at me in Tisdale's piece, which I've come to associate with unsupportable 'skeptic' nonsense:
- Short time frames, focus on small regions of the oceans/world (cherry-picking)
- No statistical analysis of trend(s) versus variation (i.e., math), just rhetoric that any statistical analysis would show invalid
- Claims that 'models fail', ignoring the physics basis
- Red herrings - for example, going on about models when the article under discussion is about observations
- Claims that the variable of interest isn't measureable (when that actually invalidates their own argument(s) as well)
- And "Buy my book", when said book has no peer-reviewed support
I may have have missed a few bits of nonsense - I didn't bother to check every assertion. But when there are so many red flags, I consider it safe to conclude that the article containing those errors isn't saying much worth reading.
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garethman at 01:01 AM on 19 October 2013Does the global warming 'pause' mean what you think it means?
Thanks KR, I did indeed write that, but that is from a lay persons perspective. I wanted to check how accurate his essay was and a useful way of doing that is to get the experts here to dig a bit deeper and explain any mistakes in a way that I, as a lay person will be able to make sense of. The word interesting by the way can be applied to many things, they do not have to be correct! In some ways it is really difficult and long winded to check out all the facts in any essay item by item on both sides, thats why it is really helpful to have critical appraisals in this way by people who have previous experience.
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Dikran Marsupial at 00:48 AM on 19 October 2013IPCC model global warming projections have done much better than you think
VeryTallGuy, I would say Tom's arguments show that most if not all of the hiatus can be explained by ENSO, but cannot show that it is caused by ENSO. Thus both Tom and the IPCC are right AFAICS, looking for other causes of the hiatus is just part of normal science (keeping an open mind), however Tom is right in suggesting that there is no pressing need for an alternative explanation as it is already quite well explained by ENSO. This sort of thing is a limitation of science, it is very difficult to show that X caused Y, only that Y can be explained by X.
The way science works is that if you can't show that the existing explanation doesn't explain the observations, or that your hypothesis provides a better explanation, then you probably shouldn't put much confidence in it. At the moment ENSO (i.e. internal variability) is a sensible null hypothesis, and it explains the observations pretty well, without ruling out alternatives.
Personally as a statistician, I am still waiting for statistically significant evidence that there actually has been a hiatus (i.e. a change in the underlying rate of warming). It is possible that there is actually nothing that needs to be explained in the first place! ;o)
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kmalpede at 00:41 AM on 19 October 2013Science of Climate Change online class starting next week on Coursera
I'm teaching a section on climate change and the censoring of science in my Theater and Justice Class at John College of Criminal Justice: dramatic readings An Enemy of the People, my play Extreme Whether about climate change scientists and deniers, and Euripides The Bacchae. I've gathered some basic readings about climate change, but wonder if you have suggestions. I would also hope to see climate change and global warming integrated more broadly into (what is left of) The Humanities.
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Paul D at 00:40 AM on 19 October 2013Science of Climate Change online class starting next week on Coursera
I have watched David Archers original videos of his lectures based on his book.
I found them very useful in understanding the basics, so I imagine the new course will be just as good with the new materials and additional learning facilities that Coursera enables. -
Does the global warming 'pause' mean what you think it means?
Tisdale also dismisses peer-review, claiming his data is from peer-reviewed sources (although certainly not his statistically unsupportable conclusions), and that the post here isn't peer-reviewed.
The SkS post isn't peer-reviewed, of course - but it's reporting peer-reviewed conclusions (IPCC AR5, not to mention a more direct reference to Nuccitelli et al 2012). And that's the major difference - the conclusions regarding OHC described in the IPCC are supported by science and good practice, while Tisdale's conclusions are based on cherry-picking, misunderstandings of statistics, and confirmation bias towards his personal "it's all ENSO and climate shifts" framework.
garethman - Over on WUWT you wrote "I suppose Dana’s essay and Bob’s both seem pretty plausible...". I would have to disagree.
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VeryTallGuy at 00:30 AM on 19 October 2013IPCC model global warming projections have done much better than you think
KR, I think you misunderstand me. I wasn't trying to suggest that ENSO isn't part of natural variability.
Tom presents a view that ENSO explains most if not all of the hiatus (using IPCC terminology)
AR5 seems to focus on volcanoes and solar, and does not split out natural variability at all.
So I wonder if I'm missing something, and Tom seems well informed to comment.
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numerobis at 00:28 AM on 19 October 2013Does the global warming 'pause' mean what you think it means?
I'm confused how Tisdale's response could possibly be qualified as "interesting" -- he has already written the same before, Nuccitelli here is pointing out Tisdale (among others) is wrong in several ways, Tisdale responds by ... making exactly the mistakes that Nuccitelli is pointing out in this article?!
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dana1981 at 00:27 AM on 19 October 2013Does the global warming 'pause' mean what you think it means?
As usual Tisdsale is still focusing on surface temperatures and ignoring ocean temperatures. He does have a valid point that 0-700m ocean warming has slowed a bit, but only because 700-2000m ocean warming has accelerated. He's guilty of the same type of cherry picking I discussed above, just regarding surface ocean temps in addition to surface air temps.
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garethman at 00:08 AM on 19 October 2013Does the global warming 'pause' mean what you think it means?
Many Thanks for your response KR.
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IPCC model global warming projections have done much better than you think
VeryTallGuy - "...from internal variability..." includes the ENSO, one of the primary and in fact easily identified internal variations of the climate. It's hardly unattributable.
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Does the global warming 'pause' mean what you think it means?
garethman - "Interesting", in the Bob Tisdale sense. Or nonsense, really.
Tisdale, as usual, focuses on extremely short time periods (2005-2013 for ocean temps, 2000-2013 for air temps, neither of which has statistical significance), on small regions of the world oceans rather than the globe as a whole (cherry-picking), on surface sea temps only while seemingly dismissing the energy accumulation in the volume (2D vs. 3D cherry-picking), disses the satellite temps while ignoring their agreement with surface temperature data sets, tosses out the old 'can't trust the models' myth, etc.
He even attempts to toss all of the ocean heat content data by inappropriate scale comparisons - yes, the energy throughput of the climate is very large, but no, that doesn't block our ability to measure changes in temperatures.
Quite frankly, having looked at Tisdale's writings before, I would consider this one more (and rather boring) Gish Gallop of myths and misunderstandings.
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garethman at 23:44 PM on 18 October 2013Does the global warming 'pause' mean what you think it means?
Bob Tisdale has written an interesting response to this as published in the Guardian. http://wattsupwiththat.com/2013/10/18/dana-nuccitelli-cant-come-to-terms-with-the-death-of-the-agw-hypothesis/#comment-1452081 I would be really interested to see how Dana views this response and whether he feels it is valid.
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Dikran Marsupial at 21:46 PM on 18 October 2013CO2 lags temperature
dvaytw, yes the rate of warming per unit CO2 does indeed decrease with increasing CO2 concentration, which is why equilibrium climate sensitivity is usually presented as the temperature rise for a doubling of CO2, rather than for a fixed increment.
CO2 solubility in the oceans is sensitive to both temperature and the difference in partial pressure of CO2 between surface ocean and atmosphere (Henry's law). Fortunately the difference in partial pressure is currently a stronger influence than temperature, which is largely why atmospheric CO2 has only been rising at half the rate of anthropogenic emissions.
David Archer is a top scientist working on the carbon cycle, and has some lectures etc. on his website that are well worth watching. He has also written a nice primer on the carbon cycle (see also his papers via google scholar).
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dvaytw at 21:41 PM on 18 October 2013Temp record is unreliable
Thanks guys for all the tips. My initial tactic was to point out to him that there are so many temperature records showing the same basic pattern; if the measurement system were flawed, errors would be in all directions and there wouldn't be such obvious similarity between them. I also pointed him to a very useful pair of charts: on Wikipedia, 'temperature records by countries'. A quick glance of the 'hottest temperature records' vs. 'coldest temperature records' shows that the former outnumber the latter by a large margin in the last couple decades. So even just looking at that, the trend is pretty obvious.
I have another question, but I don't want to keep bothering y'all for answers, so maybe you could just direct me to the most pertinent article, in response to this point of his:// ...if anyone wants to claim that CO2 levels in the upper atmosphere are causing ground level increases in temperature, there would need to be much greater warming there, which is demonstrably not happening. //
PS - Moderator, please feel free to delete any of my "please help me with debate" questions to the forum if you feel they are off-topic or don't contribute to the discussion! Thanks in advance! -
dvaytw at 21:00 PM on 18 October 2013CO2 lags temperature
Dikran, thanks... that was exactly what I needed. Can you point me to a good online source to read more about this particular topic?
Also, a couple clarifications, please. When you say "temperature only rises logarithmically with CO2", does that mean that the rate of warming per CO2 concentration actually decreases as concentration increases? (I know this is a dumb question... sorry!)
About ocean solubility increasing with atmospheric concentration, is that also affected by temperature?
Finally, to JH: I apologize if I appear lazy in not using the search engine; however the problem I often find is in properly wording the inquiry and in searching through extraneous links. People are often better at pinpointing what you want and getting you the answer with minimum hassle. I spend a lot of time in these debates, and I try to minimize the time I spend on research as much as possible for obvious reasons (IE, no one's paying me!) That said, I feel I've learned so much about the topic in recent years maybe I should start working towards a degree!
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garethman at 20:43 PM on 18 October 2013Time to change how the IPCC reports?
The infrequent release of IPCC reports does not really bother me, with such a comprehensive and complex document it takes me a long time to read and understand it in any detail.
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Dikran Marsupial at 19:06 PM on 18 October 2013Why Curry, McIntyre, and Co. are Still Wrong about IPCC Climate Model Accuracy
SASM If you want to learn about models, then there are some very good books that are well worth reading on the subject. I have "A Climate Modelling Primer" by McGuffie and Henderson-Sellers, Wiley (there appears to be a new edition available shortly), which I would recommend. I would also recommend "Principles of Planetary Climate" by Raymond Pierrehumber (Cambridge University Press), although that is generally more concerned with basic physics and more basic models than GCMs. I have used GCMs for my research, and it took a lot of background reading before I had a good grasp of the essentials.
The IPCC have made all the data from the model runs publically available, including information about the forcings, so if you want to know how this is done, there is nothing to stop you from getting the data and finding out the answers to your questions. You appear to have a suitable background for this kind of work, but you just need to learn the basics of climate modelling first, before reaching judgements.
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VeryTallGuy at 18:58 PM on 18 October 2013IPCC model global warming projections have done much better than you think
Tom Curtis @79
Your analysis of the hiatus vs ENSO is interesting and IMHO convincing. However, it doesn't seem to be the view of IPCC AR5 who don't mention ENSO specifically but say
The observed recent warming hiatus, defined as the reduction in GMST trend during 1998–2012 as compared to the trend during 1951–2012, is attributable in roughly equal measure to a cooling contribution from internal variability and a reduced trend in external forcing
and on which external forcings
primarily due to a negative forcing trend from both volcanic eruptions and the downward phase of the solar cycle.
Which basically reads as "mainly volcanoes and the sun, plus unattributable variability"
Your perspective on the AR5 conclusions would be interesing.
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garethman at 18:37 PM on 18 October 2013Does the global warming 'pause' mean what you think it means?
The fairly simple point that occurs to me is the temperatures overall have not fallen, if they have not fallen the trend is still for warming, even if this slowdown in rate lasted a thousand years.
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chriskoz at 17:07 PM on 18 October 20132013 SkS Weekly News Roundup #42A
'Australia to see worse ElNino drought'
You bet. No need to mention the record fires in NSW thanks to that drought, everybody's heard the news.
However, I want to mention the other part of the story: the wetter than usual ElNino conditions shall be predicted in the NE Pacific (or Pacific NW in US-centric nomenclature). Accordingly, we're seen just that: torrential rains and even rare tornado in Seattle as reported here. So, many pieces of evidence align for that case.
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scaddenp at 17:05 PM on 18 October 2013Why Curry, McIntyre, and Co. are Still Wrong about IPCC Climate Model Accuracy
"The devil is always in the details." Agreed - which are not going to get in blog comments. If you are ready for that, then you should be moving on the primary literature and WG1 works pretty well as an "index" to that.
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StealthAircraftSoftwareModeler at 13:33 PM on 18 October 2013Why Curry, McIntyre, and Co. are Still Wrong about IPCC Climate Model Accuracy
Moderator JH @183: Okay, fair enough. I’ll take the blame for starting the pissing contest. I do want good communication. Honestly! It is very easy to miscommunicate in email and upset people, and that is when they know who you are. Blog posts greatly amplify this effect because people will shoot off because of the anonymity. But I’m sure I’m not telling you anything new as a moderator.
Moderator Response:[JH} Been there. Done that. Let's all move forward in a civil manner.
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StealthAircraftSoftwareModeler at 13:30 PM on 18 October 2013Why Curry, McIntyre, and Co. are Still Wrong about IPCC Climate Model Accuracy
John Hartz @184: Oh, I would. I wouldn’t do anything like contact GISS. Why would they waste their time talking to me? I understand that.
Your link to CM101 is broken, by the way, but I found it with Google. In looking at #2 “Understanding Computer Models” – I have some experience with every one listed, and enormous experience with some (i.e. flight simulators). The 101 video was extremely simple; I’m sure it is aimed at the masses, but remember I am a software modeler with a computer science and physic degree and 30+ years of experience. I’m looking for a lot more meat and the details. The devil is always in the details.
I’ve got Chapter 9 printed out. Hate that I nearly killed a tree, but I skipped all the references in the middle, and printed two pages per page, so that saved a bunch of paper.
Moderator Response:[JH] The most prominent feature of the Climate Modeling 101 website is the National Acadamy of Scinces report,
I highly recommend that you study this report if you are sincere in your stated goal of better understanding how global climate models work.
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scaddenp at 12:58 PM on 18 October 2013Why Curry, McIntyre, and Co. are Still Wrong about IPCC Climate Model Accuracy
"There has to be a way of telling the model about..." well of couse there is. Forcings are input into the model. The CMIP experiment is about getting the different modelling communities to run the same forcing experiments and comparing results. The forcings to use are on the site but I see it is still down due the goverment shutdown.
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John Hartz at 12:41 PM on 18 October 2013Why Curry, McIntyre, and Co. are Still Wrong about IPCC Climate Model Accuracy
SASM @ 179:
I highly recommend that you do more homework about GCMs before you begin to correspond with various modeling groups.
In addition to reading Chapter 9 of ARM 5, you should careful go through the Climate Modeling 101 website created by the National Academy of Sciences. [Link fixed - I hope.]
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StealthAircraftSoftwareModeler at 12:35 PM on 18 October 2013Why Curry, McIntyre, and Co. are Still Wrong about IPCC Climate Model Accuracy
Moderator PW @179: So it is okay for Dikran to accuse me of Dunning Kruger syndrome, and state I haven’t bothered to find out about models – which is EXACTLY why I’m on this site. Then he states I think my field is better than climate modeling, when I’ve said no such thing at all! He can kick me all over, tell me to read up climatrology, which has nothing to do with anything in this thread and try to send me on wild goose chases. That isn’t obfuscation? C’mon.
BTW, what question have I failed to answer and is being noted and tracked? I apologize if I missed one, but trying to discuss things with an angry mob can be confusing.
Moderator Response:[JH] You came to this website with a chip on your shoulder. If you lose that, people will respond to you with civility.
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