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bozzza at 00:50 AM on 9 August 2015Statistics says the long-term global warming trend continues
I'm curious: how do they test for departure from sinusoidality?
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Lloyd Flack at 19:19 PM on 8 August 2015Statistics says the long-term global warming trend continues
The have tested for departures from linearity by fitting change point models and polynmial models. What I wish they had also done was fit a generalized additive model including a smoothing spline or something similar and test its departure from linearity. This gives a smooth curve not of a predetermined form. It is something that I would have tried on such a data set.
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mancan18 at 09:14 AM on 7 August 2015We are the Asteroid - Scientists’ Heighten Concerns About Global Extinctions
Stating that the rate of extinction is 10 times the rate of previous great extinctions may or may not be an exact figure but it certainly indicates that something fairly significant is happening and needs to be taken notice of. It is just another indicator in the many lines of evidence that global warming and climate change is happening. It also seems that the rate of human caused erosion is 10 times the natural erosion rate. When taken with the huge rise in greenhouse gases due to human activity in a relatively short time and the high rate of forest depletion then it should come as no surprise that extinction rates are so high. Unfortunately, no-one seems to have have any idea what that might mean for us as a species. Let alone not completely understanding the Earth as a complete climate system, no-one seems to have a complete understanding of the Earth as a complete ecosystem. We don't know what will happen to us when critical species in the food chain that supports us disappears. Archeology and palaeontology studies all indicate that whenever humans settled an area of the planet without a human presence then the megafauna disappeared in a relatively short time. Also, this extinction was not all necessarily due to hunting but due to the human impact on their existing supporting ecosystem. Now that the impact of our activities is global, so if the past is any indication, rather than give deniers/skeptics comfort, it should give pause to all of us until we completely understand what is going on.
Acting on climate change is the great challenge. It means a change in the technology we use to generate power and it means a change in the fundamental way market economies operate. In the past, technological changes that have had a significant impact on human society and made our lives better, like motor cars, electricity, aircraft, jet airliners personal computers, mobile phones and other technologies now taken for granted, seem to have taken around 20 or 30 years to become fully integrated into mainstream society. This integration was initially driven by the well-off (and the military) choosing to buy the earlier versions of the technology, because it was trendy and something new to investigate. Because the well-off could afford the higher initial prices, it allowed the businesses to further develop the technology and reduce costs so that the technology could be afforded by the rest of society. The technology required to make the U turn needed to alleviate the worst aspects of climate change needs to be implemented in a very short time period. This will not necessarily occur in the needed time by simply waiting for the well-off to generate the necessary demand required to drive down costs and allow the needed technology to penetrate main stream society. I'm sure that if more people could afford it, more would choose renewables as their main source of power and it would become mainstream. Unfortunately, climate change is not necessarily seen as trendy by many of those who can afford to actually do something about it.
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bozzza at 06:31 AM on 7 August 2015Charles Koch gets some climate science right, but economics wrong
Certainly. Trying to look at it logically I would have to say that obfuscation is a necessary skill- whatever the cost- in the business of making money because solid rationale (meaning the numbers) would be needed before any major reinvestment in plant and material or other general major change in plans.
Thus the divestment game is where it's at...
Only solid numbers are going to convince the business community to act. As a greenie I would argue that may be too late of course so the battle is getting the numbers together. In this way business versus science is like iron sharpening iron... there is a solution to all our woes it's just the politics of obfuscation does nuts in, lol!
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Rob Honeycutt at 05:32 AM on 7 August 2015Charles Koch gets some climate science right, but economics wrong
bozzza... I've always had the sense that they've merely surrounded themselves with people who tell them what they want to hear. It's a well-funded form of confirmation bias.
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bozzza at 04:28 AM on 7 August 2015Charles Koch gets some climate science right, but economics wrong
It's all in the use of 'mealy-mouthed' language. People like that will argue black is white if you give them the time to do it. It's called indirect argument and it is employed to confuse...
He's in a psychosis called greed!
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veleroazul at 03:13 AM on 7 August 2015We are the Asteroid - Scientists’ Heighten Concerns About Global Extinctions
The truth is that if the planet warms by 7.2 ° C to 8 ° C, then a mass extinction of all species would occur, including our species.
If the planet warms 2ºC would enter into an irreversible cycle, but in reality we are in an irreversible cycle. I mean, the disappearance of the Arctic and has a huge influence on the destabilization of clathrates located bottom of the Arctic Ocean.
Our impact, I'm not a demagogue or want to be a VIP person, our presence is like the impact of a large meteorite. We are influencing anturales cycles of all components of the Earth and in all components of its atmosphere. It decreases oxygen increases the presence of CO2 and other gases and chemicals that have never existed until humans appeared it shows.
I was fascinated by the space race and the vital support needed by the astronauts in space. Astronauts need complex supports to live in space, are some supports without which it would be impossible to survive.
As the atmosphere of the planet Earth has been generated over millions of years. Its nitrogen is derived from living things, there was nitrogen if no living organisms that generate it, just as there would be no oxygen. Our atmosphere would be much finer.
But now, we are destroying our life support in the only planet where we can live. No other planet. Nitrogen decreases, increase the CO2 and decreases oxygen and increased concentrations around and diminish the other, to the extent reach us poison.
The reality is that if we ourselves disappear.
If the planet warms 2 ° C, then the entire surface of Greenland would enter into merger. 7ºC if heated, all the ice on the planet would enter into merger. Over time the oceanic conveyor belt will stop and the ocean is stratified.
We will see major changes in the Gulf Stream, of course. Warming already affecting the depths of the Arctic Ocean in the area and as methane clathrates lso that area is issued. Also they are increasing methane emissions in Antarctica, but not much.
And most troubling of this is that as we hope biblical migrations, we believe that much dessestabilizaran governments to deal with a chaotic situaicones aprte by overcrowding in itself, and by climate changeModerator Response:[RH] Starting at the point where I've struck as warning, you need to support your claims with citations to actual research.
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ubrew12 at 02:12 AM on 7 August 2015Charles Koch gets some climate science right, but economics wrong
Charles Koch: "There’s a big debate on that"
You would know. You paid for it.
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Tristan at 01:12 AM on 7 August 20152015 SkS Weekly Digest #31
Granted it's unlikely to see the light of day, but would a plane releasing emissions from even higher in the atmosphere than the typical airliner be even worse than it is at 30,000ft?
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Raenrfm at 00:50 AM on 7 August 2015Human CO2 is a tiny % of CO2 emissions
Tom Curtis @ 273, in order to accurately determine whether the co2 leads or lags temperature, should you not be taking the fourier transform of each data set to accurately determine the phase relationship? It just seems to me looking at your graph (casually eyeballing it), looks like there is a slight phase shift with co2 lagging temp.
Moderator Response:[PS] Please do not let this discussion of CO2 lags/leads relationships wander off onto topics discussed in detail on "CO2 lags temperature" or "CO2 increase is natural, not human caused". It is very important to note that Tom has detrended the series because he is looking for change in CO2 in response to a temperature change. Ie Co2 is both a forcing and a feedback. As feedback it does of course lag temperature. Note also that the feedback CO2 is small (8ppm) cf forcing (~100ppm). Please take further discussion to a more appropriate place.
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One Planet Only Forever at 00:33 AM on 7 August 2015We are the Asteroid - Scientists’ Heighten Concerns About Global Extinctions
ryland@3,
As I implied, the most unacceptable way of succeeding that can be gotten away with is the most successful in the current socio-economic system because it inappropriately values the easily manipulated popularity of things and uses a fatally flawed limited and distorted monetary measure to determine the value of things.
That system can clearly encourage some people to develop an unacceptable desire to do the least acceptable thing they can get away with. And it has developed a lot of unsustainable perceptions of prosperity. Many people actually are not as well off as they think. They are only able to enjoy things more for a short while by getting away with less acceptable unsustainable ways of behaving.
And as you point out the popularity of getting away with benefiting from unacceptable things is difficult to overcome.
So I agree with you regarding what the problem is. But I am not sure you recognise it as the problem that it is, as the thing that "must be changed". You seem to believe that the perceptions of prosperity among the current more fortunate are deserved and must be allowed until a cheaper better way is developed. I disagree.
The developed cheaper less acceptable ways of benefiting need to be curtailed even if it means that some already fortunate people actually become less fortunate. If the leaders of the moment of a specific nation will not lead toward that required change then global leadership will have to impose measures to induce such leadership to "change their mind and disappoint some of the people in their nation and disappoint the unacceptable ones among the global wealthy and powerful people." Mind you, as others have noted a good life for everyone could develop if the ones who try to get away with less accceptable ways of benefiting are kept from succeeding.
That is actually what is happening. At the highest levels the battle is being fought between those who recognise the problem and recognise who the trouble-makers are, and the trouble-makers (those who want to prolong the support and power they get from the trouble-makers). And there clearly is no future for the successes of the second group. They can only benefit for a short time while they support the creation of more problems that the people they are fighting against will have to deal with.
And the better understanding of developing climate science and all the other developing better understanding of the unacceptability of the trouble-makers will eventually win. But the longer it takes because of the ease with which manipulative marketing can succeed the more damage that is done by those who are not interested in understanding the unacceptability of their perceived prosperity.
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howardlee at 00:25 AM on 7 August 2015We are the Asteroid - Scientists’ Heighten Concerns About Global Extinctions
ryland @3 Your question about quantifying species loss is a good one. We can subdivide the question into 3 issues: the rates of species loss, calculating that from fossil evidence, and estimating the total number of species inhabiting the planet.
To take the last point first, the idea that we still have not identified all the species that exist today, Bill Bryson addressed this eloquently in his book "A short history of nearly everything" when he described scientists finding new species of bacteria just by scooping soil from their back yard. Basically, the vast majority of those unknown species will be microbes of one kind or another. To compare modern rates of extinction with those of the past scientists use what is preserved in the fossil record, from microscopic plankton to large animals, and compare the species loss rates today with those of the past.
To take the first 2 points, these have been examined and rexamined by science over time. The best recent summary of this that I am aware of is by Norman Macleod of London's Natural History Museum here (sorry full paper is behind a paywall). His paper summarizes the history of scientists' identification of several episodes when the rate of extinction (as indicated by fossils large and small, in the sea and on land) was much larger than the intervening times, notably work by Norman Newell in 1963. You can plot the extinctions by biological Family, Genus, or species and get slightly different results, but they consistently show several extraordinary eipisodes of biodiversity loss. The "big 5" of these mass extinctions are the end-Ordovician, late-Devonian, end-Permian, end-Triassic, and end-Cretaceous. But there are other less extreme extinction episodes in the fossil record, such as in the Capitanian, Aptian and Cenomanian time periods.
With the exception of the end-Ordovician event, all have been linked to Large Igneous Province events and associate global warming episodes.
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howardlee at 23:53 PM on 6 August 2015We are the Asteroid - Scientists’ Heighten Concerns About Global Extinctions
ryland @3 - to address your last question: In most past mass extinctions volcanic emission of greenhouse gasses drove climate change and ocean acidification, as well as other environmental destruction, leading to mass extinctions.
More detailed explanations can be found here, here and here.
The "volcanic" phenomenon that triggered those catastrophes should not be confused with the kind of volcanic eruptions we see in the modern era or even since humans first evolved. The events associated with abrupt global warming and mass extinctions are known as "Large Igneous Provinces." The most recent LIP was the Columbia River Basalts 16 million years ago - a baby compared to the end-Permian or end-Triassic versions, but still associated with a kick in global warming (although not linked to a mass extinction).
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tmbtx at 23:48 PM on 6 August 2015We are the Asteroid - Scientists’ Heighten Concerns About Global Extinctions
Ryland,
1. There need not necessarily be a drop in standard of living. Investment in R&D could even enhance it while still addressing the climate. Is it a sure thing? Of course not, but the likely drop in standard of living coming due to our impact on the planet is going to be worse.
2. Not knowing everything about every species is entirely different from doing "pure guesswork". True many of these numbers are estimates but they are well informed estimates.
3. Volcanoes or climate change? Not sure what you mean. Volcanic activity like the Siberian or Deccan traps released lots of CO2, as are we. It's not either/or. But "We are a large igneous province" doesn't make as catchy a statement as "We are the asteroid."
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jgnfld at 23:44 PM on 6 August 2015We are the Asteroid - Scientists’ Heighten Concerns About Global Extinctions
Re. Ryland...
A rather extraordinary hypothesis.
What, exactly, is your hypothesis for positing differential extinction rates between characterized and uncharacterized species? That is a rather extraordinary claim and extraordinary claims usually require extraordinary evidence. What is it that you posit listing a species does that makes it more susceptible to extinction?
For my part, I think all water in the abyssal oceans that has yet to be observed acts differently from water everywhere else. As you say: "Who can definitively say one way or another?" -
ryland at 21:21 PM on 6 August 2015We are the Asteroid - Scientists’ Heighten Concerns About Global Extinctions
One Planet Only Forever @2. Your exposition, enhanced by your MBA training and life experience, doesn't address the crucial question. How will any government persuade its citizens to give up their aspirations for themselves and their families and accept a reduction in their standard of living and in their prospects for the future? You state "Appealing to emotion is far more powerful than appealing to reason" and a very strong emotional appeal to humans is their current and future personal economic well being. Serious attempts to reduce either are likely to be met with equally serious opposition.
On another topic. In the piece from Yale Climate Connections it is stated "the rate of species loss the world is experiencing is “much much higher” than the rate at which species naturally originate, with the inevitable result that global diversity is being reduced. Kump of Penn State says the current rate of species extinction is 10 times that of massive extinction events that have occurred previously, and he points to climate change and the high incidence of volcanoes as a “common threat” in those extinctions"
However it is also stated that "And Ceballos says an under-appreciated concern is that there are countless species of plants, animals, and microbes on Earth that humans do not even know about: so many species not having a scientific name that “we don’t even know” the extent of the losses".So if humans don't know about "countless species" how can we possibly know the current extinction rate is greater than 10 times that of previous massive extinctions? How can we possibly know the extinction rate is greater than the the rate at which species naturally originate? If you don’t know what you’re dealing with any comparisons are purely guess work. Realistically any comparisons can only be based on known species but perhaps the unknown species aren't being affected. Who can definitively say one way or another? And for that matter how can the true magnitude of the previous extinctions be assessed as again there would have been many unknown species?
And one fnal question. Was it volcanoes or climate change that had the greater impact on previous extinctions? If volcanoes then current attempts to reduce global temperatures may not be as productive as is believed in reducing species extinctions
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One Planet Only Forever at 13:03 PM on 6 August 2015We are the Asteroid - Scientists’ Heighten Concerns About Global Extinctions
My interpretation of the thoughts of Naomi Klein and many others is that the awarness of the unacceptable things going on in human societies and economies being raised by climate science, and other developing better understanding of the unacceptability of what has been developed, must lead to a significant change of what is valued and how its value is determined.
Humanity developing to be a sustainable part of a robust diversity of life on this amazing planet has always been the only viable future for humanity, regardless of the impressions of prosperity that can temporarily be created by pursuits based on profitability and popularity.
My MBA training and life experience help me understand that economically it is possible to have an advanatage if you are willing to try to get away with doing something you know is unacceptable. It will always be cheaper (and therefore more profitable and more likely to be popular), to do something less safely or more wastefully or to create more harm "if you can get away with it".
Some major changes are needed so that the climate, and so many other things, do not continue rapidly changing due to the pace and rapaciousness of human pursuits. The current rules made up by humans have led to unacceptable developments at an unacceptable pace. Those rules based on the supremacy of profitability and popularity are clearly a failed experiment producing a reaction that is difficult to curtail or even slow down.
That perpective raises serious questions about the legitimacy of the wealth and power of many of the currently wealthy and powerful. That is why attempts to better understand what is going on and raise awareness of that better understanding face attacks that are based on the rigorous science of manipulative misleading marketing. Appealing to emotion is far more powerful than appealing to reason.
Unlike the hard work of science striving to better understand something and then sharing that an understanding that may be contrary to what many people prefer to believe, misleading marketing just requires appealing stuff to be made up as much as can be gotten away with for as long as it can be gotten away with. After all, there is lots of perceived, but likely unjustified, wealth and power at stake.
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denisaf at 11:27 AM on 6 August 2015The most influential climate change papers of all time
This is an interesting review of the progress in the view of scientists of the nature of climate change. However, the important issue is how much understanding do the leaders of society have of the irreversibility of the rapid climate change and ocean acidifcation that is underway. They need better understanding so they wiil promote both policies to reduce greenhous gas emeissions as rapidly as possible as well as measures to cope with the consequences, such as sea level rise and increased storms, floods and wild fires.
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Rob Honeycutt at 09:43 AM on 6 August 2015We are the Asteroid - Scientists’ Heighten Concerns About Global Extinctions
I had never before made the connection that a loss of a species is a loss of genetic information accumulated over billions of years.
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bozzza at 13:08 PM on 5 August 2015It's methane
So, you are saying why Carbon-Soil Initiatives will never be an accepted method to combat climate change?!!?
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Tom Dayton at 05:56 AM on 5 August 2015Statistics says the long-term global warming trend continues
A good source of links to explanations of issues with satellite temperature measurements is a comment by Christopher Hogan on RealClimate.
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One Planet Only Forever at 05:29 AM on 5 August 2015Statistics says the long-term global warming trend continues
knaugle,
The main point about the UAH and RSS history is that neither of them represent to surface temperature. They represent the temperature higher in the atmosphere where there is less effect of increased CO2, hence a smaller trend.
Mind you, the higher elevation values have shown much more response to a strong El Nino such as the 1997/98 one. If the current El Nino builds to a similar level then the sattelite data may cease to be a favorite denier reference, at least until several years after this inconvenient event when they can once again claim "there has been no warming since 2016 so all of the science is wrong".
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knaugle at 02:22 AM on 5 August 2015Statistics says the long-term global warming trend continues
You get a slightly smaller warming trend with the RSS satellite data, but there it is a lot easier to "cherrypick" and claim no warming at all the past 20 years. I do think any article like this needs to at least address the difference, because I know a lot of deniers definitely point to it.
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bartverheggen at 01:02 AM on 5 August 20152015 SkS Weekly News Roundup #31C
I wrote a detailed reply to the claims made by Fabius Maximus regarding our PBL survey. It comes down to the first question having an effective plateau value at 78% if you include all respondents, since so many answered "don't know", "unknown", or "other". We have good reasons to believe that this was because the question was difficult to answer to the level of precision required by the answer options. Talking that into account, and looking at responses from both Q1 and Q3 leads to the conclusion that indeed there is a strong consensus.
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deathtokoalas at 18:46 PM on 4 August 2015It's methane
the more important point is that agriculture itself (minus land-use issues, transportation, pesticides, etc) should be carbon neutral, in the long run. the methane only takes a few years to decay back into c02, and then it gets recycled. if you ignore the transportation, and you take the pesticides out, and you offset the land-use with new planting, there isn't a net increase - it's just a redistribution from the soil to the trees, which can then be pulled back to the soil.
this argument is still floating around. that's the key point in combatting it: the only net source of carbon into the atmosphere is from underground, that is fossil fuels. organic farming with proper offsets for clearing is (excluding transportation issues) actually carbon neutral in the long run. -
bozzza at 12:55 PM on 4 August 2015Statistics says the long-term global warming trend continues
I think the Arctic sea ice looks like it's disintegrating. My rationale is that stagnation is close to death and sinusoidal waves seem to be forming around the lower 2-standard-deviation boundary in the Arctic sea-ice extent graphs.
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chriskoz at 12:24 PM on 4 August 2015Statistics says the long-term global warming trend continues
Tamino's blog post is much richer in details rather than this Guardian article. The original blog is dated 30 Apr, so 2 months before the paper by Foster & Abraham. Essentially the paper is the "polished out" version of the blog. I enjoyed reading the blog not only for Tamino's expert teachings but also for his juicy comments re those who deny the science
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ubrew12 at 06:33 AM on 4 August 20152015 SkS Weekly News Roundup #31D
For anyone interested: here's another set of climate info and links for this week from Mary Ellen Harte at Huffington Post.
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michael sweet at 03:53 AM on 4 August 2015Statistics says the long-term global warming trend continues
Grant Foster (Tamino) is the coauthor on this paper. Much of the data in the paper have been posted on Open Mind, Tamino's blog.
It is interesting to see how the other papers presented address the question of what a "haitus" is and how it can be measured. Hopefully after 2015 the haitus will be resolved in the popular press, but the "skeptics" will probably keep it going as long as they get traction.
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jgnfld at 01:23 AM on 4 August 2015Statistics says the long-term global warming trend continues
H'mmm. Competently done statistics never suggested otherwise. Tamino, among others, has pointed this out on many occasions.
Cherrypicking is always incompetent whether done by deniers or physicists not well trained in statistical inference. -
makiem at 13:18 PM on 3 August 2015Climate Data for Citizen Scientists
Climate agencies provide a great service by putting their data files online, however, the organization and format of these files often makes it challenging for citizen scientists to compare series.
Moderator Response:[PS] Commercial link deleted. If this account is used for spam, then it and all associated posts will be deleted. One and only warning.
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Tom Curtis at 09:58 AM on 3 August 20152015 SkS Weekly News Roundup #31C
If anyone is interested, "The editor of Fabius Maximus" has participated in a discussion of this topic at And Then There's Physics. As part of his participation, he tried to indicate why he thought his mathematical prestidigitation was significant. I responded:
"Editor of the Fabius Maximus website:
“Yes, I agree with this formulation. I believe that’s what I said. The dimensions of climate scientists’ consensus is a vital input to the public policy process. These surveys provide a valuable check on the IPCC.
….
I don’t see much value in examining these things under a microscope. The headline result (combining 1a and 1b) is what it is, providing a direct comparison to the keynote finding of WG1 of AR4 and AR5 — and for comparison with the many other similar surveys (which this improves upon).”Complete nonsense.
The IPCC result is the work of specialists in attribution studies surveying the relevant literature over a 12 month period, and distilling the results of that literature into a report. It is not, and is not intended to be a survey of the consensus opinion of all ‘climate scientists’, where the later is so loosely defined that a geologist being a coauthor of a single paper discussing paleoclimate counts as a “climate scientist”, ie, the effective definition for the Verheegen survey (once the “unconvinced”, ie, those invited to respond solely because of their expression of a political opinion on the web, and without regard to actual study of, or publication in regard to climate science).
If you wanted a double check on the IPCC on attribution, the proper method is an independent literature survey on attribution. As an approximate alternative, you could survey the opinion of climate scientists who specialize in attribution studies asking them as to:
1) Central estimate of the percentage contribution of anthropogenic (and/or GHG) to recent warming;
2) Their upper and lower bounds at 90 and 95% confidence on the attribution;
3) Their estimate as to the proportion of attribution experts whose central estimate lies within the IPCC value; and
4) Their estimate of robustness of the evidence in favour of their opinion (ie, how likely they think it is that their view of the central estimate will have changed significantly with 10 more years of information).A general survey of climate scientists and deniers without regard their expertise in attribution is not a check on the IPCC.
What the Verheggen survey is a check on is not the literature surveys such as Cook et al, but on the misinterpretation of the literature surveys which treats them as surveys of scientists rather than of papers. It is also an update and check on Doran et al 2009, which found that:
“Results show that overall, 90% of participants answered “risen” to question1 and 82% answered yes to question 2.In general, as the level of active research and specialization in climate science increases, so does agreement with the two primary questions (Figure1). In our survey, the most specialized and knowledge-able respondents (with regard to climate change) are those who listed climate science as their area of expertise and who also have published more than 50% of their recent peer- reviewed papers on the subject of climate change (79individuals in total). Of these specialists, 96.2% (76 of 79) answered “risen” to question1 and 97.4% (75 of 77) answered yes to question2.”
Note that the finding of Doran et al that agreement with the consensus rise with both specialist knowledge of climate science and with increased publication (as a proxy of greater expertise). The appropriately corrected percentage of agreement (74% among climate scientists; 84.5% among those having published 30 or more papers) are less than the nearest corresponding result from Doran et al. That may be because of the more precise nature of the questions, or may be due to a decline in certainty. The first is almost certainly the case, but the second cannot be excluded from the data available."
I also included a summary of my post above, for those who want a shorter version.
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Tom Dayton at 09:43 AM on 3 August 2015Climate models are even more accurate than you thought
Is there a CMIP-5 model output dataset that is narrowly targeted at layers of troposphere above “surface,” against which the RSS and UAH variety of indices properly should be compared?
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Phil at 08:22 AM on 3 August 2015Climate models are even more accurate than you thought
A question this post and Kevin's comment @3 prompts is this.
GCM's provide global temperature projections, whereas the observed records have limited coverage. Kevin has used infilling, using the kriging technique to make the observations more global (As it were). But presumably the reverse could also be done - namely taking the subset of grid cell output from the models that match the coverage of a given temperature record (say HadCrut4).
This would obviously only be of use in making model-observation comparisons, not for future projections, but I wonder whether anyone has tried this, or conversely whether there is a flaw in my idea?
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bozzza at 01:49 AM on 3 August 20152015 SkS Weekly News Roundup #31C
..this, in turn, will lead to a convergence in the form of nomenclature, will it not!??!
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PhilippeChantreau at 01:26 AM on 3 August 20152015 SkS Weekly News Roundup #31C
Jenna, if Tom Curtis' answer is too much detail for your friends, you can ask them why they're so intent on denying the existence of a consensus, while at same time arguing that science is not done "by consensus." Most deniers have forgotten by now that it was originally their myth that the science was ambiguous. As Tom points out above, the consensus really is a convergence of research results in published papers. There is no doubt as to where the weight of the evidence is pointing
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Tom Curtis at 15:42 PM on 2 August 20152015 SkS Weekly News Roundup #31C
jenna @2, the claim echoes those made by Fabius Maximus, and echoed by Joanne Codling three days ago. They relate to the release of additional data from Verhenger et al (2014). (Note, the PDF document is a data release, not a new paper - contrary to the misrepresentation by Codling.)
A couple of things are worth knowing about the data.
First, the authors invited responses from a number of groups chosen for their having authored scientific papers on climate change plus a small group invited because they had signed "... public statements disapproving of mainstream climate science". That group represented just 2.4% of invitees, but 4.7% of respondents. We are told that "about half of [the respondents only invited because of public political statements against climate science] only published in the gray literature on climate change"; ie, that they are not climate scientists at all. Further, even for the "about half" who are climate scientists, it is unlikely that that many of them would have been invited from a random sample of climate scientists. Indeed, we know that they would not because there is not a 50% overlap between the "unconvinced" and those invited on their merits.
Fairly obviously, because the rest of the respondents were invited based on their names appearing of authors on climate science related papers in the scientific literature, that introduces another bias into the group. Those who have published fewer papers are less likely to have been invited. Ergo, even ignoring the deliberately introduced bias in favour of the "unconvinced", the sample is also biased in favour of frequent publishers. Ergo the the sample does not represent a random sample of climate scientists, and therefore it is impossible to infer from the sample frequencies the frequencies of particular beliefs among climate scientists in general. The results are merely indicative, and when we look at patterns among subsamples, informative.
Second, the survey explicity asked about the respondents breadth of knowledge in climate science. That is very important because "climate science" is a multidisciplenary subject with a very complex field. As a result, many climate scientists are very expert in a particular issue relating to climate science without therefore being expert in all, or even many aspects of climate science. In fact, among respondents only 34% indicated that their "general knowledge of physical climate science" was "broad" or "quite broad", with another 31% indicating that their knowledge was only "slightly broad", or that it was "not broad" at all (Question 8a).
A similar question was asked about depth of knowledge of even one aspect of climate science ("one or more aspects of physical climate science"), with only 38% indicating it was "very deep" or "quite deep" on even one aspect, while 35% indicated it was only "slightly deep", or "not deep" on even one aspect of climate science. The low level of stated depth of knowledge would be a function of two factors. One is the level of comparison. Scientists would compare their depth of knowledge to the acknowledged experts in the specialist field (aspect), so that even "slightly deep" knowledge may well represent at least an undergraduate level of understanding of the topic. Further, because climate science is multidisciplenary, coauthors of climate sciense papers may be authors because of their specialist knowledge in a related field, but not in how it applies to climate science. A paper on dendroclimatology (determing past climates from tree rings) may include as an author an expert in tree rings who has not studied any aspect of climate science beyond the effects of temperature and precipitation on treering density and width.
Given these stated limits on the knowledge of climate science by the respondents, it is absurd to argue (as Joanna Codling does) that:
"Fabius Maximus suggests we exclude the “I don’t knows” which brings up the number to 47%. Since these are “climate scientists” I don’t see why those responses should be excluded. An expert saying “I don’t know” on the certainty question is an emphatic disagreement with the IPCC 95% certainty."
Climate scientist is not the same as "expert on attribution of temperature increases", the latter being a distinct and very small subset of the former. Therefore when a climate scientist says about an attribution question that "I don't know", it is safe to assume that is because attribution is not their area of expertise, and that they should not be included among the experts in that area.
So, where does the 43% come from? Essentially, Maximus takes the percentage of respondents who agreed that 50% or more of "global warming since the mid-twentieth century can be attributed to human induced changes in atmospheric greenhouse gas (GHG) concentrations" (question 1a), which is 65.9%. He multiplied that by the percentage that agreed that the certainty was "extremely likely" or "virtually certain" (65.2%), thereby obtaining a percentage that agreed with the IPCC AR5 both with respect to the attribution level and certainty (43%).
So, even on face value, the claim becomes that only 43% of a non-representative group of climate scientists and skeptics without necessarilly having detailed knowledge on attribution agree with experts in attribution who have spent more than a year in a detailed review of all the relevant data on attribution both on amount and certainty. To that, I think, the appropriate response is, "so what". Without a detailed study of attribution, climate scientists have no independent knowledge of the level of attribution, let alone the certainty of the attribution. Do Maximus and Codling realy expect detailed study of (for example) ENSO, will magically confer the knowledge of not just the best estimate of the attribution percentage, but also the certainty of the estimate? Perhaps they do. Codling at least certainly seems to believe it is possible to make detailed and exact attribution statements by studying just the Sun - and may well carry a similar magical view of science across to other areas. But just because they live in a fantasy land is no reason for us to take them seriously.
Of course, many, including many who don't have an investment in "anything but CO2" being the cause of recent warming may find such a reponse unsatisfying. For them it may be necessary to examine the numbers.
If we do that, the first thing to notice is that the IPCC AR5 says that:
"More than half of the observed increase in global mean surface temperature (GMST) from 1951 to 2010 is very likely due to the observed anthropogenic increase in greenhouse gas (GHG) concentrations."
But that:
"It is extremely likely that human activities caused more than
half of the observed increase in GMST from 1951 to 2010."(My emphasis in both quotes)
As the survey question relates to the effect of greenhouse gases, it is the first statement, not the second that is the relevant comparison. That being the case, if you want to compare those who agree with both the attribution level and the certainty, it is the certainty of the first statement (not the second) that should be used. That immediately lifts the percentage to 65.9% (attribution) * 89.3% (certainty), or 59%. Puting it simply, Maximus fudged the issue by using an incorrect comparison. Without that fudge he could not have claimed a minority of scientists agreed with the IPCC.
The second thing to notice is that the percentage increases significantly if we eliminate the non-climate scientists and the overrepresented "skeptics" from the sample. This is a necessary step if we want to interpret the result as anything meaningful with relation to climate scientists.
As it happens, 14 (15.9%) of those "unconvinced" respondents agreed with the concensus that more than 50% of recent warming is due to changes in GHG concentration. Removing those 14 from those agreeing on attribution, and the other 74 "unconvinced" from those 'disagreeing' lifts the attribution percentage to 68.4%, and hence the total agreeing on both attribution and certainty is lifted to 61%.
The third thing is that not only the "I don't knows" but also the "others" should be excluded from the response. The first because (as note above) "climate scientist" is not the same as "expert on attribution" so that when they say that they do not know, that response should be taken as a statement of personal ignorance, not (as Maximus and Codling would have it) just a variant formulation of "it is unknown". That is, a statement of personal ignorance is not a conclusion that the experts are wrong in stating that they know something.
The "other" category needs to be excluded because it is logically incoherent. The available responses allowed you to respond that there was "no warming", or that the cause of the warming was "unknown". It also allowed you to respond that GHG was responsible for "less than 0%" of the warming. That is, it covered all logical bases. For something to be "other" you have to agree that warming was greater than zero (to exclude the "no warming response"). You further have to agree that the answer to the attribution question is known (to exclude the "unknown" response), known by you (to exclude the "I don't know" response, and that GHG caused neither less than nor more than 0% of the warming (to exclude all other possible responses). Having done that, you are at least a sixth of the way to dining at Milliways. Put simply, the "other" responses are inchorent and therefore should be excluded.
Excluding these two cagegories excludes 222 responses from all responses, and 7 responses from the "unconvinced". That means excluding them raises the attribution level to 74%, and the 66%.
To summarize, if we did a valid comparison with the IPCC AR5, and did not pad out the survey numbers with known "skeptics" and by including explicity statements of ignorance and incoherent results to pad out the denominator, the proportion we would obtain would be, not 43%, but 66% agreeing on attribution and certainty, and 74% agreeing on attribution. That is, Maximus has deflated the agreement to fit his narrative by 35% at minimum. (Given that the survey is of climate scientists in general, not of researchers into attribution in particular, I would say he has deflated it by 58%.
Having said that, I would still not call 74%, let alone 66% a consensus. It is a supermajority. This should bring some caution in the over interpretation of studies like Cook et al (2013), which showed a 97% concensus in published literature - not among climate scientists. That however, has been evident for a while. What is known, however, is that the more expert climate scientists are on the topic, the more likely it is that climate scientists will agree with the IPCC consensus. The same is shown with Verheggen et al, with 84.5% of respondents having published 30 papers or more (and exlcuding those who express personal ignorance or have an incoherent response) agree with the IPCC on attribution. Only 8.5% think GHG concentrations are reponsible for less than 50% of warming, or think there has been no warming; and only 7% think the answer unknown. (Percentages calculated by pixel count, and are only accurate withing approx 0.5%). No doubt the percentage would be even greater among climate scientists with experience in attribution studies.
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Rob Honeycutt at 15:29 PM on 2 August 20152015 SkS Weekly News Roundup #31C
Jenna... I believe that comes from JoNova. I would suggest locating the original research she's quoting and see if it agrees with what she's saying.
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rkrolph at 14:16 PM on 2 August 20152015 SkS Weekly News Roundup #31C
jenna,
You don't need to keep debunking something that has already been debunked. See #4 of "most used climate myths" listed on this site. If you really want to, just ask them to provide the evidence for their claim and then it will be easy to show that it is nonsense.
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jenna at 11:07 AM on 2 August 20152015 SkS Weekly News Roundup #31C
Please, can someone from this website write a debunking of the latest denier scam saying "the 97% Consensus is now 43%" ?
That's all my denialist friends have been talking about lately, it's driving me nuts!
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wili at 09:35 AM on 2 August 20152015 SkS Weekly News Roundup #31C
"Earth now halfway to UN global warming limit"
Glad someone who could publish had the same idea I did a couple weeks ago here.
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bwilson4web at 03:53 AM on 2 August 2015Water vapor in the stratosphere stopped global warming
Hi,
I was surprised to see this chestnut arise again in a PriusChat forum. Thanks to the search function here I quickly found this article that identified 'Solomon 2010' as the source. Google quickly snatched a copy of the paper and quickly revealed one of their sources, the Microwave Limb Sounder (MLS) is still operating and the data publicly available.
It turns out, MLS shows the 'Solomon 2010' claim that humidity in the stratosphere going down did not remain the case. At least one subsequent paper which can be identified at the MLS as well as the site itself says stratospheric humidity is rising. It looks like the 'Solomon 2010' paper was premature.
Bob Wilson, Huntsville, AL
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Rob Honeycutt at 01:55 AM on 2 August 2015Climate models are even more accurate than you thought
knaugle... I think pretty much every climate scientist everywhere would say that.
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knaugle at 00:26 AM on 2 August 2015Climate models are even more accurate than you thought
Who is the New Zealand scientist SS SkS quoted who said something like:
"Even without the computer models, we would still be very concerned about the effects of warming"?
Moderator Response:[JH] Please adhere to our protocol in your future posts.
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Climate models are even more accurate than you thought
It's all adding up which is good - measurements matching models gives more confidence to all. I have two comments though. Firstly after seeing these adjustments I can't help thinking that they are pretty obvious - why hasn't someone done this ages ago. Congratulations to those who did do it though.
Secondly on the Denial 101 course there was reference to a paper which analysed where on the planet the main differences between the models and measurements were occurring over the last period of years. The answer was something like North East America and North/central Asia during winter were the main time and place where the measurements were cooler than the models. The paper concluded by saying something like that this needed to be further investigated/understood to improve modelling. So there's a small niggle that the recent paper discussed in this post has legitimately bought the models closer to measurements, but not by addressing where the main difference is occurring?
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Kevin C at 16:54 PM on 1 August 2015Climate models are even more accurate than you thought
Rolf: Whether the first author of the paper is a climate scientist or a critic of climate scientists is a question on which some climate scientists are equivocal.
We didn't adjust the observations. We simply tried to use the same methods to get a temperature from the models which are used to get the temperature of the real world.
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denisaf at 13:23 PM on 1 August 201510 Things We Learnt From Reddit About Understanding Climate Change
Climate change and ocean acidification have been instigated primarily by fossil fuel usage. That is the stark reality. Decisions that society makes about the future operation of the technological systems of industrialized civilization can do no more than slow down climate change and ocean acidification. The greatest need is for society at all levels to understand that. With that understanding, measures could be implemented to deal with the problems stemming from this response of nature to the unintended consequnces of using fossil fuels to supply energy.
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bozzza at 12:34 PM on 1 August 2015Climate pledge puts China on course to peak emissions as early as 2027
@4, don't worry about the 'trouble-makers': they are allowed to exist only under condition.
Markets are meant to be robust, thus the existence of said 'trouble-makers' is for mutual benefit and when it isn't they have nothing to hide behind. Saying all that means they won't disappear of course: it's called synergy! Thus things take time is all.
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bozzza at 12:22 PM on 1 August 2015Climate models are even more accurate than you thought
Scientific method relies on critique: as does any method, else it would cease to be called method.
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Rolf Jander at 11:26 AM on 1 August 2015Climate models are even more accurate than you thought
Unfortunatly a study by climate scientists that says their models are good will only be met with derision. Any talk of adjusting data, no matter how nessesary will be called "fudging the data"
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