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Klapper at 02:18 AM on 11 April 2014Climate Models Show Remarkable Agreement with Recent Surface Warming
@Tom Curtis #56:
I checked the Hadisst1 dataset for the NINO3.4 region (165 to 120W, +5 to -5 North) instead of getting the NINO3.4 index directly from climate data explorer and got a very slightly different answer for the last 100 years (-0.0047C/decade), but still no warming trend is apparent. I think my point is this: the dataset I used has no gaps and also has no long term trend so I believe it to be a valid proxy for ENSO, although I could detrend HadSSTv3 detrend it and use that too except it's full of temporal holes.
As for your second point I'm not basing my hypothesis the models are running hot on a single trend. Before you had posted your rolling trend graph I had tried to do the same thing but when SKS said I had to "host" I didn't bother. I'm basing my hypothesis on approximately 120 trends since 2004 that show an increasing divergence between CMIP5 model projections and the empirical data. You are right I did my error calculations on only the last trend in this series however.
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Poster9662 at 01:43 AM on 11 April 2014IPCC says adapt and mitigate to tackle climate risks
Dhogaza @10 There is nothing in my comment that indicates anything about my personal beliefs on global warming/climate change and to suggest there is is both michievous and unsubstantiated. With regard to your claim that "deniers" did not discover solar cycles or Milankovich cycles or plate techtonics etc is pure supposition.. When most of the things to which you refer were identified/described, the current divisions on climate change did not exist. How can you be certain that, for example, Milankovich or Schwabe, might not have been "deniers" today?
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P.T. Goodman at 01:39 AM on 11 April 2014IPCC says adapt and mitigate to tackle climate risks
Human adaptation will be necessary in the short and medium time-frames. Mitigation is essential for the long-term. What can adapt or be adapted? I see no evidence that plants and animals as they now exist naturally stand much of a chance in adpating to a drastically altered global climate. Basically, they are toast without mitigation.
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One Planet Only Forever at 00:10 AM on 11 April 2014IPCC says adapt and mitigate to tackle climate risks
Here is another way to make the point I presented in my earlier comment.
Humanity needs to be looking towards the hundreds of millions of years that this planet whould be the amazing home to life that it currently is. Consuming non-renewable resources of this planet is fundamentally unsustainable (absolutely complete recycling of such materials forever would be acceptable). And activity that damages the diversity and profusion of life is also clearly unacceptable.
Justification of the increased damage of current unsustainable and damaging activities and the increased risk of creating more rapid and more difficult adaptation challenges can only be by the creation today of absolutely certain benefits in the future that more than offset those future consequences.
An economic evaluation that pretends there will be economic growth into the future is not a valid justification. There would have to be absolute certainty of the benefit that will exist into the potentially more difficult future.
So the challenge to anyone claiming adaptation is the answer would be: The objective must be to provide a sustainable better future for all life on this amazing planet. Provide proof of the things being done right now with the benefit obtained by these unsustainable and damaging activities that will have real substantial value for future generations facing the resulting consequences. The evaluation must include significant costs for reduced access to non-renewable resources and reduced diversity and profusion of other life. And if there is any uncertainty about the evaluations the future costs must be magnified, and the evaluated future benefit must be reduced absolutely certain (no net-present-value calculation that pretends a future cost has less inherent value than a current day cost).
By that method of evaluation the past 40 to 50 years of global development have been worse than worthless, though they are perceived to be popular and profitable because the ones measuring success have not had to properly consider the future. They haven’t even had to properly consider the current immediate impacts of what they want to benefit from doing. The success of that attitude to gain popularity and be supported by the methods of evaluating the creation of value (the profitability measurement method), is what needs to change, or it is certain that the future for humanity will continue to be worse, because current day activities are worse than worthless in the future.
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dhogaza at 23:38 PM on 10 April 2014IPCC says adapt and mitigate to tackle climate risks
Poster:
"I don't think sceptics dismiss climate change as not happening I think it more that they remain unconvinced that human activity is the sole and root cause."
But apparently they (and you) do believe in this strawman mischaracterization of climate science, which does not clam, and never has claimed, that human activity is the sole and root cause of climate change. Denialists didn't discover Milankovich cycles, after all. Nor solar cycles. Solar dimming? The geological processes which which modulate CO2 concentrations in the atmosphere? Plate tectonics, which move the continents around causing very large climatic side-effects? Any of those discovered by denialists? Nope. All discovered (along with many, many things I'm not mentioning) by mainstream science, and their relationship with the earth's climate discovered by scientists as well.
What have denialists contributed? A lot of blog posts, for the most part.
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ZincKidd at 22:41 PM on 10 April 2014IPCC says adapt and mitigate to tackle climate risks
One big part of "adaptation" is going to have to be a willingness to accept refugees from island nations that have lost their fresh groundwater. Tuvalu comes to mind as one of the first, but I suspect we'll be seeing similar problems in a lot of other places before long, the Bahamas, much of Polynesia, etc. This is a tough problem-- as these people would no doubt like to keep their national identity.
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bjchip at 21:32 PM on 10 April 2014Recursive Fury: Facts and misrepresentations
What I have always found fascinating about the "conspiracy of scientists" theorists is the more likely conspiracy they ignore. Getting scientists to agree on things has a lot in common with herding cats, except that the cats are a lot easier to get moving in the same direction and probably better paid... whereas the financial wizards and CEOs funding entities like CEI and Heartland whence the lies about science emanate, the people who control the WSJ and Forbes where they are most commonly published... THOSE people have given us the LIBOR fraud, the FOREX scandal, the Global Economic Crisis, Billion Dollar Bailouts, "Too-Big-To-Jail", and a list of further scandal and corruption far far longer. They are the professional conspiracists and they pay themselves rather well. As someone pointed out, if scientists were in this to make money they're doing it wrong.
Yet that never quite touches their ideation, and that itself is a bit of a puzzle because as a conpiracy theory goes it has a lot more potential. So why doesn't it take off? Why isn't it a MORE common theory than the one that is espoused about climate scientists? ...or is it merely less vocal even though it is more widely held?There's a semi-relevant question in this because more than one conspiracy theory is available to consider. How is the conspiracy theory chosen by the theorist, why is one more "popular" than the another?
Not going to go into the debate with our visitors.
The difference between the consensus of the climate science and the consensus of the scientist's opinions, is an important one to make, and is missed by many. When one examines the papers to find 97% one is examining the consensus of the science, not the people. It makes the absense of contrary science far far more telling.
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CBDunkerson at 21:12 PM on 10 April 2014IPCC says adapt and mitigate to tackle climate risks
In my experience most 'skeptics' hold multiple beliefs: 'Global Warming isn't happening, but if it were happening it wouldn't be serious, and if it were serious it wouldn't be due to human activity'.
The 'Global Warming isn't happening' and 'Global Warming will not be serious' crowds have been in decline, but claiming that they don't exist is just nonsense. What's funny is that the science establishing human causation is even stronger than that showing that significant GW is happening. They've retreated to the least viable argument.
On adaptation, the problem is that AGW is now causing enough damage that adaptation is clearly needed... but the more effort we devote to adaptation the less severe the immediate consequences will be and thus the more likely we are to hold off mitigation and thereby produce eventual long term consequences that we won't be able to adapt to by any means short of massive population reduction.
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Earthling at 20:01 PM on 10 April 2014IPCC says adapt and mitigate to tackle climate risks
Post #7 should read, only fools could believe.
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Earthling at 19:58 PM on 10 April 2014IPCC says adapt and mitigate to tackle climate risks
Poster @ #6 You are correct, only fools believe could that sceptics claim climate change isn't happening.
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Poster9662 at 18:45 PM on 10 April 2014IPCC says adapt and mitigate to tackle climate risks
Chris Snow @ #2 I don't think sceptics dismiss climate change as not happening I think it more that they remain unconvinced that human activity is the sole and root cause.
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ubrew12 at 17:42 PM on 10 April 2014Fox News climate change coverage is now 28% accurate, up from 7%
The U.S. Supreme Court recently reaffirmed its opinion that Money is Speech and thus subject to First Amendment protections against efforts to limit its influence in elections. If you look at those statistics for Fox News and CNN, it seems plain that, often, Money is the very opposite of Speech. Nobody wants to talk about one of the most important issues of our Age because, frankly, the money is directing them not to talk about it. Money isn't Speech. Money is a bullhorn or a muzzle, depending on how the donor wants it directed.
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One Planet Only Forever at 14:50 PM on 10 April 2014IPCC says adapt and mitigate to tackle climate risks
The real problem is that people claiming it is "best" if "we" just adapt, are people hoping to prolong their enjoyment of the undeserved benefits of creating the rapidly changing climate. And they are pretty certain they will not be the ones facing the consequences.
The warmer the callous disregard for the future consequneces force things to become, the more rapid and signficant and unpredictable the climate will change. And the local changes to be adapted to will become very difficult to predict in a manner that can successfully be adapted to.
Development of a sustainable better future for all life on this amazing planet is the only viable future for humanity. Rapid significant climate change, combined with all the other damaging consequences of the current massive unsustainable human consumption madness, make the future of humanity "less certain".
The current socioeconomic systems with their adoration of popular image creations and profitability clearly are not guaranteed to develop a better future. It seems quite certain that they never willingly lead to the collective effort of the entire population toward the develoment of anything but a series of failed unsustainable pursuits that only benefit a few in their moment.
And proponents of the "adaptation is better" approach know these are the most certain facts of the matter, and they obviously don't care, for the obvious reasons.
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chriskoz at 13:21 PM on 10 April 2014Watch Episode 1 of James Cameron's "Years of Living Dangerously"
My response to John Hartz@3 was deleted (i presume by accident - together with some unrelated driveby trolls - because it is on topic andinformative), so I'm reposting it:
Not just Heidi Cullen needs to be singled out here. I'm really excited to see someone like Tom Friedman involved in the production and speaking on Face the Nation. Tom's book "Hot Flat & Crowded" is simply a phenomenal peice of journalism about global warming & surrounding politics & FF industry. A must read, that I've already resommended elsewhere. If this series' narrative is similar to the Tom's book, then even though I haven't seen it yet, I can only concur with previous commenters: watch it!
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Tom Curtis at 13:07 PM on 10 April 2014Climate Models Show Remarkable Agreement with Recent Surface Warming
Klapper @55:
1) The HadISST1 (not HadSSTi) is an observational dataset with interpolation, not a reanalysis. It is currently based on the HadSST2 dataset, which has been superceded by the HadSST3 dataset, which I used. Dropping the default requirement from the KNMI explorer from 30% valid data points to 5% valid data points, I was able do download an almost continuous annual data series from 1914 onwards. It misses only the year 1946, but many years prior to 1949 have less than four months data, and many months have less than 30% valid data points. However, based on that I then calculated the trend from 1914-2013. It is 0.045 C per decade, with a standard deviation of the trend of 0.022 C per decade. That is, if you ignore the poor quality of the data prior to 1949, the trend is significant. Given that the interpolated data field based on an obsolete dataset does not even preserve the sign on that trend, I would say so much the worse for trusting the interpolation until they update the dataset used.
2) I don't need to quantify the overcooling. The point of this excercise it to determine by how much, if at all, climate models run warm with respect to observations for the underlying trend. I have quantified that by comparing a large number of thirty year trends over different periods so that positive and negative biases on the discrepancy due to ENSO and volcanism will have largely averaged out. The only thing I need to specifically point to the volcanism for is to demonstrate that estimates of the discrepancy based on a single 30 year trend are unreliable.
However, as you are basing your estimate of how warm the models are running based on a single trend, you do need to estimate the volanism induced discrepancy and the ENSO induced discrepancy, (and the differences in forcing induced disrepancy) to make that estimate. Instead you treat the naive estimate as if it were a reasonable indicater. I have shown it is not.
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chriskoz at 13:04 PM on 10 April 2014Watch Episode 1 of James Cameron's "Years of Living Dangerously"
John Hartz@9,
Thanks for pointing that. Indeed, I ignorantly assumed that the indonesian rainforest formation time is comparable to that of an average boreal forrest. But as I'm learning from this link:
The lowland peat swamps of Borneo are mostly geologically recent (<5000 years old), low lying coastal formations above marine muds and sands [10][11] but some of the lakeside peat forests of Kalimantan are up to 11,000 years old.
it is clearly not. Removal of peat swamps is not the ordinary forest removal. If most of the emmisions come from 20 m deep peat, then based on the above numbers, I have to increase my original restoration estimate at least 10 times to some 1Ky or even 100times to few Ky. That's still far shorter than FF restoration but it may change the conclusion of my original post, depending on the definition of "forever". That timespan can be called "essentially forever", on the human life timescale,
As a sidenote, I've learned from the link above, that the peat fires in 1997, could have been largely responsible for a huge spike of emmision rates in 1998, as seen on this NOAA picture, so their contribution of peat destruction is by no means negligible.
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Klapper at 12:08 PM on 10 April 2014Climate Models Show Remarkable Agreement with Recent Surface Warming
@Tom Curtis #53:
The trend in NINO3.4 for the last 100 years (Oct 1914 to Sep. 2013) is -0.002C/decade. There is no long term warming trend in ENSO. The data I'm using are HadSSTi downloaded from KMNI data explorer. I see zero trend in NINO3.4 over the last century so if you are finding trends, then they are likely driven by the PDO, another cycle which the models cannot emulate. The downloaded data show no missing months in the 144 year period available.
You can argue that this must be "re-analysis" data and therefore subject to high error, but the underlying warming trend in the central east Pacific appears to be statistically indistinguisable from zero. Hence I can't agree with your claim that there is an underlying warming trend in the NINO3.4 dataset.
As for your claim my "thoughts don't matter" I would point out you have not quantified your claim the models overcool during major volcanic events so you're doing a lot of hand waving but you haven't backed that claim up. Mind you I actually agree, but until you quantify this overcooling, statements like "potentially by a large margin" have no backup.
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Rob Honeycutt at 08:39 AM on 10 April 2014IPCC says adapt and mitigate to tackle climate risks
LCBozo... I'm not sure I get how all the nuclear proponents always assume their solution is the only truly viable solution to the problem.
What I think you'll find is, most people who are concerned about AGW will say, we need all technologies being applied to the problem.
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LCBozo at 08:31 AM on 10 April 2014IPCC says adapt and mitigate to tackle climate risks
Our evolutionary specialization is adapting the environment, not adapting to the environment. When considering the ability to modify the global environment, doesn't the question become: what kind of global environment is the most conducive for survival — especially for those organisms which need to literally adapt to the environment?
I worked in the construction completion and startup of the sodium cooled Fast Flux Test Facility in WA State, in the late 1970s. This stainless steel reactor was a jewel in the desert, and was to be the forerunner to the Clinch River breeder reactor - which was cancelled due to political hysteria. Since then, I've worked at about a dozen DOE and commercial nuclear facilities.
If people are really serious about greatly reducing greenhouse gasses in the environment, a healthy breeder reactor program is the only truly practical means of seriously reducing GH emissions. In fact, a breeder reactor is virtually a renewable energy source, and has the added benefit of converting nuclear warheads into clean energy (a sizable portion of present light water reactors is doing just that). This would represent a stop-gap measure until practical fusion reactors would provide that ultimate energy source.
I think the nuclear energy industry went off on the wrong track by investing in huge light water reactors. Liquid metal or HTG is a more rational approach to reactor design. You could pull the plug on the FFTF while at full power — it would have simply shut down, with convection cooling.
We need not adapt the concept of adapting to. We are the earth's supreme tool makers — it shouldn't be necessary to adapt to an unhealthy mode of existence.
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Chris Snow at 06:55 AM on 10 April 2014IPCC says adapt and mitigate to tackle climate risks
So the skeptics think we need to adapt to something that they claim isn't happening?
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localis at 02:11 AM on 10 April 2014IPCC says adapt and mitigate to tackle climate risks
Adaptation will take place whatever happens for that is the very nature of human survival and has been so since we first appeared on the planet. Mitigation is the only sensible avenue that can be taken and the IPCC should remain steadfast in stressing just how dangerous it is to think otherwise.
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Rob Honeycutt at 01:12 AM on 10 April 2014CO2 is not the only driver of climate
roosaw... Here's the RF chart from IPCC AR5 that has them broken out...
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John Hartz at 00:54 AM on 10 April 2014Watch Episode 1 of James Cameron's "Years of Living Dangerously"
chriskoz:
Does your estimate of the length of time it would take to restore a rainforest in Indonesia take into account the full restoration of the peat foundation of the forest?
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roosaw at 23:34 PM on 9 April 2014CO2 is not the only driver of climate
In the rediative forcing graph it shows "well-mixed greenhouse gases". Is there a breakout of CO2, H2O, methane etc to show the relative importanct to the effect?
and a related question, when we burn a fuel we get CO2 and H2O in a 3:4 ratio (typical). Since H2O is a more potent green house gas why all the hupla on CO2 and not the incresed H2O?
Moderator Response:[TD] Water vapor's concentration in the atmosphere is limited by temperature. Putting more water vapor into the air than the air's temperature will support causes the excess water to drop out in about 10 days. Therefore water vapor is a feedback to temperature increase, not a forcing. See the rebuttal to the myth Water Vapor is the Most Powerful Greenhouse Gas.
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chriskoz at 23:31 PM on 9 April 2014Watch Episode 1 of James Cameron's "Years of Living Dangerously"
Having watched this episode, I have to single out one inaccuracy/exaggeration: Ford's reporting on Indonesia's forests cleared for oil palms. The report states that once the trees are removed/burned, the carbon sequestered in them espaces to the atmosphere and is "lost forever".
That's incorrect. There might be other environmental issues with clearing the forests and the local environmental loss may be big. But in terms of global CO2 balance, the indonesian forest removal will be balanced by increased carbon intake by the biosphere. Further, even the restoration of said forests, although hard, is possible in a timeframe of few 10s to 100 years which is much less than "forever". And certainly, those who believe we can mitigate by drawing down CO2, point to planting forests and harvesting their wood then preserving it in form of furniture as the realistic way to achieve it.
By contrast, the main source of emmisions - fossils fuels dug from thte ground - contains carbon 100s My old - and that's indeed "forever". And there are no knwon methods of reduce its most oxydised form (CO2) all the way back to the form it came from (FF), nor any method to put it back to the ground.
So the FF emmsions are litteraly milion times more serious than land clearing. I claim that undoing the damage of FF (properly, without side effects like ocean acidification) is also about the same million times harder than undoing land clearing.
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Tom Curtis at 22:41 PM on 9 April 2014Climate Models Show Remarkable Agreement with Recent Surface Warming
Klapper @53:
1) The data is not detrended, and nor has their been a lack of warming. Rather, the variation in SST in the NINO 3.4 region due to ENSO is very large relative to the warming due to global warming. The result is a large standard deviation of the values, and consequently the small trend due to global warming does not register as statistically significant. None-the-less, it is still there.
2) Re NINO 3.4 vs SOI, here is a direct comparison for the period over which we consistently have values for the SST in the NINO 3.4 region:
As a result of normalizing the values, it is easy to see that both are comparable as to ENSO values, and as to thirty year trends. It also allows a direct comparison of trends in units of standard deviations. Over the interval 1949-2012 inclusive (the period examined), the linear trend in NINO 3.4 is 30% larger than that for the SOI. That is consistent with a global warming trend being incorporated into the NINO 3.4 index (as it must be of necessity due to the nature of that index). Further, the consequences of including that trend are just as I predicted.
So, switching to NINO 3.4 does not significantly help your case; but it does have the disadvantage of incorporating a global warming signal in your ENSO index, thereby confusing the issue.
On a side note, from 1884 to 1949, blocks of up to six years data are missing from NINO 3.4. You may prefer NINO 3.4 for calculating the trend from 1916-1945, but that thirty year trend has ten years data missing from it, in two seperate blocks and is hardly reliable. This contrasts with the effectively complete record for the SOI.
3) Re volcanoes, the logic is very simple. Suppose you think models over state the temperature influence of volcanoes. From that supposition, it follows that the models will understate trends more relative to observations when it has a large number, or very large volcanoes in the last 15 years of the 30 year trend, and overstate them when the volcanoes are in the first 15 years of the 30 year trend. As the current thirty year trend has the influence of two large volcanoes in the first 15 years, that means if the models overstate volanic influence, then part of the discrepancy between models and observations is due to that problem rather than to the models running generally hot. It appears to me that you want to have your cake and eat it - it to state models overstate the influence of volcanoes, but also to interpret the full discrepancy between observed and modelled trends as due to models running hot.
For what it is worth, I am inclined to think that the models run slightly hot (about 15%), and that the models do overstate the cooling influence of volcanoes so that both factors are in play. However, regardless of what we think, you cannot assess how hot the models run in a period with trends significantly influenced by recent volcanism (such as the current period) without examining what effect the volcanoes have on the trend. You can, of course, take an average over periods when the volcanoes inflate model trends, and periods when they deflate the model trends to find the approximate average of how hot the models run with respect to the underlying trend, which brings us back to where we were eight days ago.
4) What your thoughts are do not matter. You have not provided evidence or reasoning to justify those thoughts. Indeed, your current position seems to be no different from that nine days ago when you though models ran 40-50% to hot based only on the most recent 30 year trend, and without regard to the influence of ENSO and volcanoes on that trend. Since then we have seen that:
1) Averaged accross many thirty year trends, models are on average 13-18% to hot;
2) ENSO has a substantial influence on thirty year trends, which is not reflected in the models;
3) Volcanism has a substantial influence on thirty year trends, which may differ between models and observations; and
4) If models overstate the cooling effect of volcanoes, then both ENSO and volcanic influences on the most recent thirty year trend tend to exagerate the discrepancy between models and observations - potentially by a large margin.
And you still show no willingness to revise down your estimate of how hot models run relative to observations!
Is there any point in continuing at this stage?
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Klapper at 18:56 PM on 9 April 2014Climate Models Show Remarkable Agreement with Recent Surface Warming
@Tom Curtis #52:
There is no significant long term trend in the NINO3.4 data so either the data have been detrended by the originater or there is no warming in the east central Pacific over the last 100 years. Either way, it seems it's an OK metric to use as a proxy for ENSO. I do agree the pre-satellite era Nino3.4 data are suspect since they no doubt rely on Re-analysis to fill what are probably large holes in the data.
As for the disruption volcanoes pose to the CMIP5 vs SAT trend analysis, I'm having hard time discerning your logic. Do you think the CMIP5 models do a good or poor job of emulating the radiative forcing from large volcanoes? If you believe the former, then volcanoes can't be a significant reason for the CMIP5 to SAT 30 year trend error.
I can agree the recent 30 year trend in SAT has been suppressed by an ENSO bias, which the CMIP5 models don't emulate, but I'm surprised that you think volcanoes are also part of the discrepancy. In theory the models and empirical data are both influenced by these major volcanic events equally.
Summarizing my thoughts, the current discrepancy between model and empirical data 30 year trends is partially due to the models inability to emulate ENSO, and possibly some problems with the emulation of volcanic forcing, but most of the problem is that the models run too hot, that is they have some error in the feedbacks to GHG forcing, in addition to whatever problems they have with ENSO or volcanic aerosol forcing.
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Russell at 16:31 PM on 9 April 2014Recursive Fury: Facts and misrepresentations
The 'skeptics' have subscribed to, and serially rejected, so many alternative explanations of global warming that their rejection of the flat earth hypothesis ranks as a statistical outlier.
It is unfortunate that Frontier did not conduct enough legal diligence to realize the wannabe plaintiffs would be laughed out of court.
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Tom Curtis at 13:43 PM on 9 April 2014Climate Models Show Remarkable Agreement with Recent Surface Warming
Klapper @51, IMO Nino 3.4 is clearly inferior to SOI as an ENSO index because it incorporates any global warming signal as a positive ENSO signal. That is, over time it will progressively inflate El Nino values and deflate La Nina values simply because the central Pacific SST are increasing in temperature due to global warming. If you are going to use a temperature based index, you should at least use the ratio of NINO 3.4 to the average of all tropical Pacific SST from + to - 15 degrees Latitude, and from the west coast of the Americas to the West tip of Sumatra so that any uniform warming across the Pacific is eliminated from the signal. Failure to do so renders any argument about the relative effect of ENSO and an underlying global warming trend futile in that you have incorporated the underlying trend in your ENSO signal. You will also have incorporated some part of the volcanic signal in your ENSO signal - again rendering discussion of relative influences futile.
I am not wedded to the SOI per se. An index based directly on the strength of the Walker circulation, or even better on relative Sea Levels in the Western and Eastern Pacific would also be good indices. However, we do not have accurate indices of those values extending back in time, wheras we do for the SOI.
Further, the volcanic trends are relevant to this discussion because:
a) It is quite possible that the model mean does not capture the actual temperature response to volcanoes; and certainly the observed temperature does not because there are confounding factors that cannot be eliminated (primarilly, but not exclusively, ENSO).
b) The large difference in thirty year trends between AR4 and AR5 are at least in part a simple consequence of the impact of volcanoes on the trend. As the impact of one of those volcanoes, and the one having the most influence on the trend for the last few years in the models, was scrubbed out by a concurrent El Nino in the observed record, any simplistic comparison between observed and model mean trends which does not factor in the effects of ENSO and volcanoes will come to mistaken conclusions.
c) Failure to recognize the impact of volcanism on the model mean trends will lead you to project any current inaccuracy into the future. However, that inaccuracy may be due to inadequate handling of volcanoes, but a correct determination of the underlying trend. In the later case, the underlying trend shown for the rest of the century will still be accurate.
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Klapper at 12:19 PM on 9 April 2014Climate Models Show Remarkable Agreement with Recent Surface Warming
@Tom Curtis #50:
I use NINO3.4 as my proxy for ENSO, not inverted SOI. Certainly this is a better metric in the satellite era since the SSTs are a direct forcing as opposed to SOI which is indirect. The Nino3.4 trend is in fact close to zero for the period 1916 to 1946 (my spreadsheets do use 30 year trends, i.e. Jan. 1917 to Dec. 1946, not 31, but I use the years only for shorthand). Anyway, I don't think I've made a mistake; the period in question is ENSO neutral by the NINO3.4 metric.
As for your ongoing comments about volcanoes; if you are saying they are some part of the reason for the discrepancy between CMIP5 and SAT, I can agree, but not the way you would like. Volcanoes are in fact modeled by CMIP5 so if you want to claim the models do a good job of modelling the volcanoes, then they are not part of this argument. Unlike ENSO, vulcanism affects both the models and the empirical data, supposedly equally, so they don't belong in this discussion. Either the major volcanoes are modeled well, meaning they are not part of the CMIP5/SAT discrepancy, or they are not modeled well in which case I would agree.
As for the 1969 to 1998 trend, the differences are modest compared to the current discrepancy which you accrue to ENSO error. Look at your own graph. The error just keeps getting bigger but the trend in NINO3.4 now is less in magnitude than 1998.
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citizenschallenge at 05:49 AM on 9 April 2014Watch Episode 1 of James Cameron's "Years of Living Dangerously"
Thanks for posting this. I hope the video get's around.
FWIW: "Years of Living Dangerously - facing what's happening"
http://whatsupwiththatwatts.blogspot.com/2014/04/years-of-living-dangerously-facing.html
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Tom Curtis at 04:27 AM on 9 April 2014Climate Models Show Remarkable Agreement with Recent Surface Warming
Klapper @46, sorry for the delayed response.
1) Here are the running thirty year trends on annual inverted SOI:
To determine the trend by start and end year, subtract 15 for the start year, and and 14 for the end year. Thus for the trend shown for 1931 in the graph, it has a start year of 1916 and an end year of 1945. You will notice that it has a 30 year trend of 0.213 per annum, a trend you mistakenly describe as "ENSO ... neutral". Rather than being ENSO neutral, it is the highest thirty year trend up to that date. It is just exceeded the following year, but not again exceeded till the trend of 1954-1983 (1969).
2) Here are the successive, inverted 360 month trends in stratospheric aerosol forcing as a proxy for the impact of volcanoes:
First, I apologize for the lack of dates. My spreadsheet did not want to put them in, and as I am only posting at the moment due to insomnia, I am disinclined to push the issue. The dates given on the graph are for the first initial month, and the last terminal month of the trends. It should be noted that actual volcanic response will be both slower, and more dispersed due to thermal inertia. The trends have been inverted so that positive trends on the graph will correlate with positive trends in temperature, all else being equal.
That brings us to the key point. You point to the strongly positive thirty year trend in ENSO from 1969-1998 as being a point where we would expect divergence between models and observed temperature trends. That period, however, coincides with a period with a significant negative trend in temperatures due to volcanism, as seen above. The actual negative trend for the Jan 1969-Dec 1998 is about half that at the trough indicated, but that strongest negative trend would have been delayed due to thermal inertia. Therefore it would have coincided very closely to the period you point to, suggesting that ENSO and volcanic influences are appreciably mutually cancelling effects in that period so that the observed temperature trend will be close to that due to the underlying forcing.
It should be noted that the volcanic influence becomes positive about terminal year 2002 and becomes strongly positive thereafter - an effect felt strongly in models, but cancelled by the strongly negative ENSO trend in observations.
3) Finally, here are the RCP4.5 vs Observed trends:
You will notice that in the year 1984 on the graph (initial year Jan 1969, terminal year Dec 1998), the observed trend is greater than the model trend. The precise values are: Modelled trend - 0.148 C/decade
Observed trend - 0.162 C/decade
This is despite the fact that on average observations run cooler than the models. In fact, the baseline trend for the period is about 0.2 C /decade for models, but 0.17 C/decade for observations, showing the modelled trend to have been reduced by approximately 25% due the the effects of volcanism (and a cooling sun), whereas the observed trend is scarcely reduced at all (due the the counteracting effect from ENSO).
You will also notice the clear pattern from the exaggerated model trend due to the effects of volcanism as discussed in my prior post.
To summarize, you presented two counter examples to my claims about the interactions of volcanism and ENSO in influencing the observed and modelled thirty year trends in Global Mean Surface Temperature. One of those counter examples is shown to be invalid because, whereas you describe it as ENSO neutral, it in fact shows a strong ENSO trend, and presumed ENSO influence on temperatures. The second counter example raises a valid point, ie, that we should expect the observed trend to be exagerated relative to modelled trend for the period 1969-1998. However, that fails as a counter example because the observed trend is exagerated relative to the modelled trend over that period, and even more so once we allow for the generally slightly (15%) lower observed relative to modelled trends. Detailed examination of the data, therefore, shows your "counter examples" to be in fact "supporting instances" - and shows the general validity of the account I have laid out here.
It should be noted that I do not presume that ENSO plus the standard forcings (including volcanic and solar) are the only influences on GMST. They are not - but they are the dominant influences. So much so that accounting for them plus thermal inertia results in a predicted temperature that correlate with observed temperatures with an r squared greater than 0.92
(Note, you in fact quoted 31 year trends rather than 30 year trends. I have therefore used the nearest relevant 30 year trends in discussing your points.)
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One Planet Only Forever at 23:20 PM on 8 April 2014The climate change uncertainty monster – more uncertainty means more urgency to tackle global warming
Poster @ 11:
I'm not sure I follow the basis for your comment that I ignore the burning of fossil fuels in the internal combustion engine. My third point is the catchall of the unacceptability of any burning of fossil fuels. That activity is not just fundamentally unsustainable, putting at risk the future of any economy or society that relies on it, but it creates many harmful unsustainable results in addition to the excess CO2.
My fundamental position is that the only future for humanity is for all human activity to be 'restricted' to truly sustainable activity as part of a robust diverse web of life on this amazing planet.
So my view not only includes the need to curtail any burning of fossil fuels, it includes the need to ciurtail any consumption of non-renewable resources. The only acceptable use of a non-renewable resource should be no accumulating damage done getting the resource and converting it into a useful product and absolutely full recycling of the material...forever...
Humanity has several hundred million years to enjoy on this planet. They can't consume it along the way. The same applies to any thoughts of spreading life beyond this planet. If what we spread is the current attitude we spread a damaging disease, not sustainable life.
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Poster9662 at 17:35 PM on 8 April 2014The climate change uncertainty monster – more uncertainty means more urgency to tackle global warming
Comment@10. You,apparently, blithely ignore the burnign of fossil fules by the internal combustion engine. This aspect of the "West's" profligacy is rarely mentioned as too many in the "profligate West" rely on this to maintain their lifestyle, Rather than focus on "solar and wind" more Draconian actions on use of the ICE would be appropriate
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One Planet Only Forever at 13:03 PM on 8 April 2014The climate change uncertainty monster – more uncertainty means more urgency to tackle global warming
A few points:
1. I am pretty sure that the scientific global average surface temperature increase of concern has been, and continues to be, 1.5 decgrees C. That is the temperature beyond which climate changes are likely to become less predictable combined with being more signficant. The 2 degree C limit is the result of global leaders in Copenhagen acknowledging that the failure of the most fortunate to significantly reduce the impacts of their lifestyles, including exporting larger amounts of their impacts to nations like China and India, has made it very unlikely that impacts can be limited to a 1.5 degree C increase.
2. The economic evaluations ignore one critical aspect. The people expecting to benefit most from failing to reduce the burning of fossil fuels is not the group that is expected to suffer the consequences of their irresponsible unsustainable and damaging activities.
3. The economic evaluations also typically ignore the fundamental unsustainability of burning fossil fuels. And they ignore far more unsustainable and damaging consequences than the results fo the excess CO2 that is produced.
4. Many economic evaluations actually discount the future costs, claiming a future cost is not as important as a current benefit. Though this is a valid way of evaluating alternative investment opportunities, it is a totally inappropriate way of evaluting the merits of current day activities. The only legitimate value of a current day activity is the benefit obtained into the future. By that measure it is clear that the current burning of fossil fuels is essentially a worthless activity.
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KR at 12:21 PM on 8 April 2014Climate Models Show Remarkable Agreement with Recent Surface Warming
Matzdj - My apologies, I overlooked part of your question.
"How are these effects [ENSO, volcanic action, solar changes, etc] removed?"
The scale for the effects of these variations are derived from statistical models, namely by the use of multiple linear regression of the time signatures of those variations against the time signature of temperature. See Foster and Rahmstorf 2011 and Lean and Rind 2008 for details. And in anticipation of one of your potential questions, F&R 2011 in particular examined these variations against various lag times, which means that nonlinear responses of the climate to those forcings average out to zero in the long term - any mismatch between linear/nonlinear response cancels out.
There are other methods for these scale estimates which are in general agreement - see John Nielsen-Gammons estimates of ENSO effects, or any of the many papers on the climate effects of Pinatubo.
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KR at 12:03 PM on 8 April 2014Climate Models Show Remarkable Agreement with Recent Surface Warming
Matzdj - Your first question was answered quite succinctly by Kevin C above; there are parameterizations for physics below model resolution, which are driven only by the match to observed behavior at those small scales - local physics only. There are, however, no statistically fitted parameters for global temperature response - that is an emergent result of the large scale physics, and certainly not (as you implied in your first post on this thread) a result of tuning the global model to provide a certain answer.
As to the second question, running a GCM takes quite a bit of time and effort, note the amount of computation - they are not something you want to (or can) run every afternoon, even if you have a supercomputer cluster just hanging around. The CMIP3 and CMIP5 model runs started with a specified set of forcings, including projections through the present, and were run on those common forcings for model comparison. If the set of forcings used in those sets of model runs were constantly changing, there would never be a time when all the various modellers were working from the same set of data, no way to compare models or to look at their spread.
But as to what happens when forcings don't match the projections of a few years ago, read the opening post and look at figure one.
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Matzdj10109 at 11:29 AM on 8 April 2014Climate Models Show Remarkable Agreement with Recent Surface Warming
Thanks to all who responded to my questions above. I have two follow-ups:
1. I believe I am hearing that climate models have no constants in the models whose values are determined by fit to the actual data? is that true? I am very surprised because I have been led to believe that in some cases, for instance cloud formation, that we do not understand the physics well enough to precisely put them into the model ? Can you give me a reference to review one of these models that have no constants that need to be multiple-variable-regression-fit to actual data before they can be used for forecast?
2. I also am hearing that when you remove the effects of El Ninos, La Ninas, volcanic eruptions, etc. that what's left fits the observed data really well. How are these effects removed? How is the effect of a strong El Nino removed differently than the effect of a weak El Nino, or the effect of a big volcanic eruption versus the effect of small one?
If we understand how to remove these from the models at the correct intensity of effect, based only on physics, when they occur, then we should be able to put them into the model as zero effect when they are not occurring and then add their effect each time one does occur with the effect that was predetermined for that intensity of event.
These are major short term forcings. Why aren't they included in the models to incorporate their effect each time they occur?
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gws at 08:28 AM on 8 April 2014Watch Episode 1 of James Cameron's "Years of Living Dangerously"
Note that the project comes with an educator resource linked through the main page, http://www.climateclassroom.org/. It is sparsely populated yet, but since movies generally make a good entry point for discussion, reinforcement, and motivation, it may become a useful resource, including for house (watching) parties.
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John Hartz at 07:34 AM on 8 April 2014Watch Episode 1 of James Cameron's "Years of Living Dangerously"
The Tipping Points series cited by Jim Eager premiered on the U.S. Weather Channel in October of last year. An informative article about the series, Weather Channel series takes journey to Earth's tipping points, was posted on the Mother Nature Network website on Oct 10, 2013.
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Jim Eager at 06:58 AM on 8 April 2014Watch Episode 1 of James Cameron's "Years of Living Dangerously"
Another good series is The Tipping Points,
currently showing on TVOntario
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John Hartz at 06:41 AM on 8 April 2014Watch Episode 1 of James Cameron's "Years of Living Dangerously"
Another prominent U.S. female climate scientist is Heidi Cullen, who together with Joe Romm functioned as the science advisors to the production of Showtime's ‘Years of Living Dangerously’
Climate Central has posted a video of Cullen's appearnce on yesterday's NBC News Sunday show, Face the Nation. The post is Heidi Cullen Talks IPCC on Face the Nation. Cullen also discusses her role on the Showtime series.
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gws at 03:46 AM on 8 April 2014The climate change uncertainty monster – more uncertainty means more urgency to tackle global warming
good post, giving context to the risk management nature of climate change
minor detail: IMHO, the text stating
"... the accelerating nature of climate damage costs with more warming would still mean that greater climate uncertainty translates into more climate damages."
should better be
"... the accelerating nature of expected climate damage costs with more warming would still mean that greater climate uncertainty translates into higher risks of climate damages."
since uncertainty does not directly translate to higher costs, by higher risks. The change keeps it more consistent with the remaining text, I think.
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Rob Honeycutt at 03:34 AM on 8 April 2014Watch Episode 1 of James Cameron's "Years of Living Dangerously"
I watched it just this morning. All I can say is: Fantastic!!
I'm just floored by the important work that Katherine Hayhoe is doing. She's just amazing.
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Rob Honeycutt at 03:30 AM on 8 April 2014The climate change uncertainty monster – more uncertainty means more urgency to tackle global warming
Poster... Just to add a good visual for what KR is saying about asymmetry:
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vrooomie at 03:05 AM on 8 April 2014The climate change uncertainty monster – more uncertainty means more urgency to tackle global warming
Re: KR's mention of the 'long tail:' here's but one good explication of why this is a critical, but oft-overlooked aspect of what turns out to be a widespread and poor understanding of risk analysis.
http://earlywarn.blogspot.com/2010/05/explaining-long-tail-climate-risk.html
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vrooomie at 03:00 AM on 8 April 2014Watch Episode 1 of James Cameron's "Years of Living Dangerously"
I viewed this as soon as I saw a link to do so: it's *great* to see this level of attention paid to this critical and very real issue. Along with this, and NBC's program of last night, I expect a howl of protest from the denialati, which I will listen to with great relish. The louder the scientific community makes them howl, the loonier they will appear, and the sooner we can get down to the brass tacks of doing what we *all* need to do, to mitigate the oncoming damage.
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KR at 00:19 AM on 8 April 2014The climate change uncertainty monster – more uncertainty means more urgency to tackle global warming
Poster - This is tendency, for uncertainties to increase the cost risks, is exacerbated by the near lognormal distribution of sensitivity estimates. The high tail of sensitivity estimates is much longer than the low tail, meaning that for equal probability estimates the weighted high end will increase the total risk cost far more than the equal probability weighted low end will decrease total risk cost.
Add the asymmetric sensitivity estimate to the rise in risk cost due to larger uncertainty spreads, and the financial risk is considerably higher than if we had a highly constrained estimate of climate sensitivity. Uncertainty is not our friend.
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Kevin C at 23:28 PM on 7 April 2014The climate change uncertainty monster – more uncertainty means more urgency to tackle global warming
Poster:
The conclusion is based on how financial risk is calculated. If there are multiple possible outcoomes, you have to take into account the cost of all possible outcomes, weighted by the probability of each of those outcomes.
Increasing uncertainty increases the probability of both high and low cost outcomes. However the shape of the cost curve is such that the finacial risk, calculated using the above method, increases.
This is the standard approach used by insurers, investors and gamblers for decades or centuries, however the issue is clearly confusing to a lot of people.
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Poster9662 at 22:38 PM on 7 April 2014The climate change uncertainty monster – more uncertainty means more urgency to tackle global warming
Reading the summary from the University of Bristol I am puzzled by this comment " Scientists have shown that as uncertainty in the temperature increase expected with a doubling of carbon dioxide from pre-industrial levels rises, so do the economic damages of increased climate change. Greater uncertainty also increases the likelihood of exceeding ‘safe’ temperature limits and the probability of failing to reach mitigation targets" Why is the uncertainty focussed only on increases in temperature (and on sea level rises)? Surely if the uncertainty in rises is increasing, isn't the uncertainty of stabiity or even falls in temperatures (and falls in sea levels) also increasing. Why does greater uncertainty also not increase the likelihood of not exceeding "safe trmperatures'? Why is ths aspect not considered worth a mention?
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