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Comments 31601 to 31650:

31601. OSweetMrMath at 12:43 PM on 7 February 2015
       Claims that climate models overestimate warming are 'unfounded', study shows
       

       bjchip,

       I read the paper at Nature, and then I read the climateaudit post until I got bored. It didn't seem to be responsive to the basic claims of the paper, just throwing up a bunch of noise leading to a meaningless dismissal of Marotzke. The substance of the criticism isn't much more than the quote, "The statistical methods used in the paper are so bad as to merit use in a class on how not to do applied statistics." which is a good insult but not an informed criticism. 

       My reason for rejecting climateaudit is that it's inherently untrustworthy, as has been well demonstrated. Nature deserves more credibility a priori than climateaudit ever will.

31602. davidsanger at 11:35 AM on 7 February 2015
       Kevin Cowtan Debunks Christopher Booker's Temperature Conspiracy Theory
       

       If one is going to compare adjusted temperature anomalies to unadjusted temperature anomalies, ought not the unadjsuted temperature anomalies be calculated relative to the unadjusted mean temperature?  Otherwise you are calculating an anomaly by comparing an unadjusted temperature to an adjusted mean.

       Or am I missing something?

31603. daveburton at 09:42 AM on 7 February 2015
       Kevin Cowtan Debunks Christopher Booker's Temperature Conspiracy Theory
       

       This is the Excel-generated plot of adj-unadj (adjusted minus unadjusted temperatures) for the 24 years which I digitized.

       Because I digitized only 20% of the years it's obviously incomplete, and because the years I digitized aren't quite evenly spaced the horizontal spacing of the plotted points isn't quite right, and because it's manually digitized from a screencap of a graph it's not completely accurate, but it's a better reflection of NOAA's global land surface temperature adjustments than "the difference between raw and final USHCN temperatures" (U.S. only) which Tom Curtis posted:
       

       Moderator Response:

       [RH] Adjusted image size. Please try to keep images to 500px width.

31604. One Planet Only Forever at 08:02 AM on 7 February 2015
       Meeting two degree climate target means 80 per cent of world's coal is unburnable, study says
       

       It is important to note that the indicated amount of stuff that can be allowed to be burned was not only based on the dangerously high 2 C temperature increase, it was based on a 50:50 chance of a 2 C increase from the amout of burned stuff.

       Structures are not designed with a 50:50 chance of staying up. And vehicle brake systems are not designed to have a 50:50 chance of working when you push the brake pedal. The discussion should be about what is allowed with a 'higher level of certainty that significant problems will not occur'. That would be something better than a 95% level of certainty, something closer to the certainty that human burning of fossil fuels has to be curtailed rapidly in spite of its potential popularity and profitability.

31605. One Planet Only Forever at 07:55 AM on 7 February 2015
       Meeting two degree climate target means 80 per cent of world's coal is unburnable, study says
       

       One thing that defiintely should be done right now is a global ban on the burning of the petroleum coke waste that is created when poor grade crude like the stuff in the Alberta Oil Sands is upgraded to a refinable material. That stuff is worse than coal and yet wealthy people are able to profit from it being burned.

       And one thing that is seldom mentioned is the potential future value of unburned buried hydrocarbons. There is the possibility that in the future, thousands or millions of years from now, there could be a really beneficial use for these resources.

       The clear problem is the current marketplace cerated by humans which erroneously relies on popularity and profitability. That system clearly has shown no interest in developing a sutainable better future. The required change of human development will require changes to the motivations of the marketplace. That will only happen through responsible leadership.

       Responsible leadership toward a sustainable better future for everyone has clearly been lacking. It has definitely been possible for irresponsible pursuers of what hey want to create popular support for, and increase the profitability of, damaging activity that cannot be sustained.

       One effective challenge to every defender of getting away with benefiting from burning buried non-renewable hydrocarbons is to demand proof from them that the future generations clearly benefit from the activity they want to benefit from. Ask them to show what they have done to ensure the future generations will definitely have a better life and prove it will actually benefit distant future generations. Even just ask them waht they think future generations will have to do when the non-renewable resources they want to benefit from burning up become even difficult to benefit from.

31606. bjchip at 07:51 AM on 7 February 2015
       Claims that climate models overestimate warming are 'unfounded', study shows
       

       I have a need for an answer to the attack on the paper from climateaudit.  

       That relies on SOMEONE someone taking up some defense of the paper from this particular attack and I note that they also attack the peer-review process at Nature.    I do not think that ignoring this is going to help. 

       In calling attention to that attack I  *have*  to consider that it may even be accurate...  any given paper might be in error without throwing any doubt on the overall science.  We all take a false position when we pretend to be perfect.  

       I do NOT not have the tools to determine WTF they are saying and I can't simply "reject" a statistical argument I do not understand.  

       No matter that I agree with  the conclusion of the original paper,  I can't use it in argument anywhere if that argument on climateaudit stands unanswered.    

       What I am asking is that someone who has the tools to understand, read over that attack and respond appropriately, here or elsewhere.    Please.    

       You know who I am and how to reach me.  If you have any doubt whatsoever, just e-mail me.    

       Moderator Response:

       [JH] The use of "all caps" is akin to shouting and is prohibited by the SkS Comments Policy.

31607. knaugle at 06:51 AM on 7 February 2015
       It hasn't warmed since 1998
       

       May need updating?  2014 now warmest year on record in several temperature databases.

31608. HK at 06:26 AM on 7 February 2015
       Claims that climate models overestimate warming are 'unfounded', study shows
       

       Cooper & Wili:
       I don’t know how deep sea pressure impacts (possibly limits) thermal expansion, but the temperature certainly does. Some time ago I made this graph showing how 1^oC of warming causes more and more expansion as the initial temperature of water rises.

       

       Note how the rate of expansion increases 3-fold from 0^oC to 10^oC and more than 5-fold from 0^oC to 25^oC. It’s also worth noting that the heat capacity of water is close to 4.2 J/g/K all the way from 0^oC and 100^oC, so the energy it takes to heat a certain amount of water by 1^oC doesn’t change much with temperature.

31609. Rob Honeycutt at 06:12 AM on 7 February 2015
       Meeting two degree climate target means 80 per cent of world's coal is unburnable, study says
       

       TomR @4...  Methane contributions certainly have been considered and are thought they will likely not have a major impact this century.

       Peter Sinclair has a very good series of videos with researchers discussing this very issue, called the "Methane Bomb Squad." You should definitely check it out.

31610. TomR at 05:48 AM on 7 February 2015
       Meeting two degree climate target means 80 per cent of world's coal is unburnable, study says
       

       I agree that 2C is way too disastrous. We probably have already crossed it since I don't think the permafrost and methane clathrate contributions have been included although they are virtually certain to have a major impact this century.

       At least some carbon appears likely to stay in the ground with New York, Scotland, Wales, and some European countries banning fracking. Also, there has been a major cut-back in exploration for more carbons. Granted, some of the cut-back is due to low oil prices, but I think some is because of the realization by industry that their reserves will be unsellable. The electric power companies are certainly running scared of PV solar. China may have peaked on coal imports. Improved battery technology with the titanium dioxide anode to the lithium ion battery may dramatically cut the cost and eliminate range anxiety. Fossil fuel cars may soon be fossils. Let's do all we can to make it a reality.

31611. gregcharles at 05:47 AM on 7 February 2015
       Meeting two degree climate target means 80 per cent of world's coal is unburnable, study says
       

       I hear the term carbon budget a lot lately, but I don't fully understand how it's calculated. I assume it would be related to climate sensitivity, or actually the climate sensitivity specifically for the effects of doubling of CO2 in the atmosphere on global mean surface temperatures. This is currently estimated to be 1.5C to 4.5C. So to compute a carbon budget, we'd look at current CO2 levels (~400 ppm) and pre-industrial values (~280 ppm), pick a reasonable climate sensitvity value like 3C, and plug them into a formula?

31612. Alexandre at 04:19 AM on 7 February 2015
       Meeting two degree climate target means 80 per cent of world's coal is unburnable, study says
       

       I haven't seen any believable hint that any carbon will stay underground unexplored. Quite the opposite: new frontiers like fracking, Arctic oil, tar sand oil and deepwater drilling suggest that we'll burn even more than all presently known reserves.

       I would love to be proven wrong. Please someone help me out here.

31613. wili at 04:06 AM on 7 February 2015
       Katharine Hayhoe's climate elevator pitch
       

       I think people are missing her point (as I hear it, at least).

       You can't get people to the science (or Logos and Ethos) if you don't first make some connection on the value/emotional (Pathos) level.

       Once people have a reason to care, or perhaps to not feel as threatened, then and in many cases only then will they be able to pay attention to stats like 97% agreement among climate scientists (Authority) and the absorption spectrum of CO2 (Science).

       It is easy for most of us to overlook just how powerfully our critical abilities in any situation are tied up to our emotional reactions.

31614. wili at 03:56 AM on 7 February 2015
       Claims that climate models overestimate warming are 'unfounded', study shows
       

       Thanks for the insights, Cooper. I do certainly know that thermal expansion isn't the only contributor to slr, but so far it is the largest single contributor (vs glacier melt, GIS, Antarctica and changes in terrestrial storage). I suppose increased evaporation rates and total humidity in the atmosphere (which is increasing) has to be figured in, too--over the long term, but also as a factor in year-to-year varability.

       But I still would have thought that, if more heat has been going into the oceans in the last 15 years than previously, there would be some notable increase in the rate of slr over the same period. I can't imagine that ice sheet loss has been decelerating over the same period in a way that would mask the thermal expansion.

       "the land-ice losses and sea-ice losses relative to their absorbed heat-of-fusion; once this ice is gone, that reservoir for absorbing heat and limiting warming simply disappears"

       I think this is an important point, and I'm sure someone has figured out exactly (or at least approximately) how much energy has been going in to melting all that ice. It makes me wonder just how fast the Arctic Ocean will heat up once it's (mostly) free of ice and recieving solar radiation 24/7 for weeks.

31615. Tom Dayton at 03:17 AM on 7 February 2015
       Claims that climate models overestimate warming are 'unfounded', study shows
       

       Sir Harry, a professional statistician who has published climate science peer reviewed papers goes by the name Tamino on his blog, which is outstanding.

31616. Cooper13 at 03:01 AM on 7 February 2015
       Claims that climate models overestimate warming are 'unfounded', study shows
       

       @wili:

       Actually, the past several decades have indicated sea level rise is substantially faster than the prior 20-30 years. A single decade is difficult to parse out of the data for a longer-term trend, but as I recall, sea levels are going up closer to 3.5mm/yr vs ~2.5mm/yr as the longer-term (early) 20th century trend.

       However, overall rise is a combination of land-ice losses and thermal expansion, so overall sea level increases cannot be naively attributed to only ocean warming.

       There is no 'deep sea pressure' mechanism that limits thermal expansion due to temperature rises I am aware of; I'd have to look up in a CRC handbook or something to see if there is any substantial variation in the coefficient of thermal expansion for water vs. pressure which might imply 'deep water' warming would have a lower or higher rate of expansion with heating. Nonetheless, any warming increases ocean volume.

       That said, one concern I have not seen addressed/discussed is the land-ice losses and sea-ice losses relative to their absorbed heat-of-fusion; once this ice is gone, that reservoir for absorbing heat and limiting warming simply disappears - has anyone calculated how much faster warming might be once a significant portion of this ice warms through that transition temperature?  The ratio of ice heat absorption to water warming is (I think) 80 cal/g-degree C; that means the energy to heat up a gram of water 80 degrees is the same as it takes to melt just 1 g of ice into water (or, the same amount of heat will warm the same mass of water 80x more). Once those ice 'heat absorbing' reservoirs are gone, the basic physics demands that overall warming w/o that phase transition will go somewhat faster. It could be an insignificantly small increment, but I have not seen that calculation/estimation.

31617. wili at 02:27 AM on 7 February 2015
       Meeting two degree climate target means 80 per cent of world's coal is unburnable, study says
       

       But since two degrees is way too high, we really don't have any 'budget.' Our carbon 'budget' is way over drawn. Every extra molecule of carbon put in the atmosphere is a molecule that we'll have to figure out how to get back out of the atmosphere as soon as possible (like, yesterday or last century). And then take many more out thereafter. (All of course without using energy that itself burns carbon...)

31618. wili at 02:20 AM on 7 February 2015
       Claims that climate models overestimate warming are 'unfounded', study shows
       

       I'm surprised there wasn't more about volcanic activity here. Surely, a major volcanic eruption (or many minor ones) could temporarily knock global tempuratures outside of the range of model projections. But that wouldn't invalidate the models.

       Has there been enough volcanic activity recently for this to be part of the slower rise in the last fifteen years? I would think that some of the slowing in the rate of heating has to do with the human made 'volcano' of aerosols especially from China's rapid industrial expansion.

       If the 'missing heat' really all is going into the oceans, shouldn't we have expected a pronounced increase in the rate of sea level rise just from thermal expansion. IIRC, that has not been the case in the last ten years. Or does heating the deep ocean not create as much thermal expansion because of the pressure?

       Thanks ahead of time for any help from any direction (except, of course, from denialists) on any of these points.

31619. Sir Harry Flashman at 02:04 AM on 7 February 2015
       Claims that climate models overestimate warming are 'unfounded', study shows
       

       Honestly, I'd be interested in seeing some comment on the claims of flawed statistical methods coming from denier blogs from someone who knows the topic.  Not looking to cast any shadows, but those blogs have influence with people and I wonder if ignoring them is always the best way to go.

       Moderator Response:

       [JH] Rest assured that members of the SkS comment team and our regular readers monitor what is being posted on the more prominent websites of Deniersville. When a formal rebuttal is needed, we will do so either by updating an existing, or by posting a new SkS article. In many cases, our reuglar readers (e.g. Tom Curtis. KR, MA Rodger, etc. ) will thoroughly debunk a denier analysis in the comment threads of this website. In other cases, we may reprint a critique originated by another pro-science website such as Tamino's Open Mind.

31620. Tom Curtis at 01:44 AM on 7 February 2015
       Claims that climate models overestimate warming are 'unfounded', study shows
       

       fungelstrumpet @3:

       "Though there are signs of desperation. He seems to be linking climate change to a socialist/communist conspiracy."

       That has been Monckton's line for at least five years now.  Indeed, if anything it represents a toning down of the rhetoric.  In his 2009 blurb for Ian Wishart's propaganda piece, Air Con (very well self named), he wrote:

       "The UN, Mikhail Gorbachev, Jacques Chirac, and other world government wannabes are plotting to establish nothing less than a global, bureaucratic-centralist dictatorship under the pretext that it is necessary to 'Save The Planet'. Ian Wishart's book demonstrates that there is not the slightest scientific reason for the new, quasi-religious belief that The Planet needs Saving. The new religion is merely an excuse for world government. World government will not, repeat not, be democratic government.

       "The 'global warming' debate is not really a debate about climatology - it is a debate about freedom. It is the aim of the growing world-government faction amont the international classe politique to take away our hard-won freedom and democracy forever. I commend [Wishart's] book ... . Those who read it will will help to forestall the new Fascists and so to keep us free."

       So whereas Monckton formerly described all of us as both (and simultaneiously) communists and fascists, he he toned down to calling us communists and totalitarians.  (Don't tell Riddley.  I'm sure he would have a fainting fit to think that such abusive language would be used in the climate debate.  He also would be forced by his logic to concede that AGW is both real and dangerous.)

       I will note as an aside that the way in which large numbers of quite influential members of the anti-climate science brigade take a known conspiracy theorist, and demagogue like Monckton seriously damns their cause far beyond anything I could manage.  If they cannot determine that Monckton's thinking is, quite frankly, nuts; and act accordingly, but rather provide a ready conduit for any rubbish he puts out, they have shown themselves completely incapable of critical thinking on the topic.

31621. alby at 01:01 AM on 7 February 2015
       Claims that climate models overestimate warming are 'unfounded', study shows
       

       I don’t think that self-defining “skeptics” will be disturbed by this study, which indeed is very interesting.

       I suppose they cannot be disturbed by any facts and arguments because imho try to convince these type of thinkers that AGW is a real and dangerous phenomenon using climate science is like to convince pious hindus that cow is not an holy creature with evolutionist biology knowledge.

       Anyhow I have a small question looking at the last graph ("15-years GMST trend..."):

       we can argue that positive Y-axis data on black circles for long period show directly a warming effect (from 1900 to 1935 roughly and from 1965 to now)?

       And also that the patterns for show period going up and down (the longest up from about 1960 to 1985 , the longest down from approx. 1925 to 1940) of the circles in the chain indicates an acceleration (up) or deceleration (down) of the general warming rate (i.e shows in other way the variability)?

31622. funglestrumpet at 00:21 AM on 7 February 2015
       Claims that climate models overestimate warming are 'unfounded', study shows
       

       I have just endured forty-two minutes and twenty-two seconds of the good Lord spouting forth about his new paper. He gets up to all his usual tricks, such as wearing several layers of clothing while indoors because it is cold outside and therefore global warming is all a hoax. Anyone with the stomache to watch it can find it here: https://www.youtube.com/watch?v=fE7r0gk5nmw (USA Watchdog channel).

       He closes with the assertion that if his paper is found to be correct, it will settle the whole issue of whether climate change is real or not. I would like to suggest that the converse is also true. If his paper is found to be incorrect, then by the same token he should accept that such an eventuality proves that it is real and that he should just shut up about the issue. I am not holding my breath! Experience says that no matter how many papers there are like this OP, he will not change his stance. Though there are signs of desperation. He seems to be linking climate change to a socialist/communist conspiracy.

       Moderator Response:

       [JH] For future reference, we discourage commenters from providing direct links to propaganda pieces produced by Monckton and his ilk.

       Warning: Watching a video like the one linked to above can be injurous to your mental health and well-being.  

31623. daveburton at 23:23 PM on 6 February 2015
       Kevin Cowtan Debunks Christopher Booker's Temperature Conspiracy Theory
       

       To address concerns about comparing data only for the endpoints (1900 & 2014), I went back and used WebPlotDigitizer to digitize a number of intermediate points. I digitized all years ending in "0" so that decadal trends could be calculated starting with year 1900, which is the earliest year in Dr. Cowtan's graph. I also digitized years ending in "4" so that decadal trends could be calculated ending with year 2014, which is the latest year for which data exists. (I didn't include the other years because digitizing all that data is very tedious!)

       Using WebPlotDigitizer, I digitized the temperatures for each plot (unadjusted temperatures and adjusted temperatures) for the following years:
       1900, 1904, 1910, 1914, 1920, 1924, 1930, 1934, 1940, 1944, 1950, 1954, 1960, 1964, 1970, 1974, 1980, 1984, 1990, 1994, 2000, 2004, 2010, 2014.

       (Note: I started over, so some digitized values are very slightly different from the values I previously obtained.)

       I loaded all the data into a spreadsheet in Excel, with these column headers:

       year   unadj_temp   adj_temp

       I then added ten calculated columns:

       adj-unadj = the difference between adjusted and unadjusted temperature.

       50yr_unadj_diff = the difference in unadjusted temperatures between the designated year and fifty years earlier. If positive, it indicates warming compared to fifty years earlier; if negative, it indicates cooling.

       50yr_adj_diff = the difference in adjusted temperatures between the designated year and fifty years earlier.

       50yr_%warm_from_adj = the percentage of the warming which is due to the adjustments, over 50-year intervals, starting with 1900-1950, and ending with 1964-2014. (Percentage is shown as "100%" if the unadjusted data indicated cooling.) The results were:
       100.0%, 22.2%, 39.6%, 100.0%, 54.4%, 100.0%, 48.1%, 96.8%, 21.6%, 30.9%, 20.7%, 17.0%, 7.7%, 7.5%.
       Note that, over the last 50 years (1964-2014), only 7.5% of the warming is due to adjustments (i.e., the adjustments increased warming by 8.1%). However, of all the 50-year intervals, that interval shows the lowest percentage of warming due to adjustments.

       70yr_unadj_diff = the difference in unadjusted temperatures between the designated year and seventy years earlier.

       70yr_adj_diff = the difference in adjusted temperatures between the designated year and seventy years earlier.

       70yr_%war_from_adj = the percentage of the warming which is due to the adjustments, over 70-year intervals, starting with 1900-1970, and ending with 1944-2014:
       89.0%, 43.0%, 28.6%, 75.8%, 23.7%, 27.4%, 35.6%, 27.2%, 16.2%, 15.9%.

       114yr_unadj_diff = the difference in unadjusted temperatures between 2014 and 1900 (0.86 °C).

       114yr_adj_diff = the difference in adjusted temperatures between 2014 and 1900 (1.16 °C).

       114yr_%war_from_adj = the percentage of the warming which is due to the adjustments (26%).

       114yr_increase_by_adj = the percentage by which the adjustments increased the reported warming (35%).

       I added all these files to my little web page about this argument between Booker and Cowtan:
       http://tinyurl.com/cowtan-v-booker
       
       The screenshot files (with and without digitization points added), digitized data files, spreadsheet, WebPlotDigitizer calibration & data file, and notes are all available in a convenient .zip archive, in case you want to check my work or do additional calculations.

       One last note: to address Tom Curtis's concern, based on the USHCN adjustments, that the endpoints migh have anomolous adjustments, I used Excel to plot adj-unadj for the 24 years which I digitized. If you download the spreadsheet and load it into Excel, you'll see that it looks like it's almost linearly increasing, though because I digitized only 20% of the years it's obviously incomplete.

31624. bjchip at 22:51 PM on 6 February 2015
       Claims that climate models overestimate warming are 'unfounded', study shows
       

       This may or may not have been hasty.   

       I see that there is some information on climateaudit that the statistical methods used are flawed.    I do not have the background to double check that.   I hope the authors can check it out and act appropriately.... quickly.     

       Moderator Response:

       [JH] Your comment appears to be a thinly-disguised attempt to castr a shadow on the information presented in the OP. If so, please cease and desist playing such a game on this website. 

       Upon further review, this comment is retracted.

31625. shoyemore at 18:15 PM on 6 February 2015
       Katharine Hayhoe's climate elevator pitch
       

       There are said to be three ways to persuade people rhetorically:

       • Logos (or Logic)
       • Ethos (or Authority)
       • Pathos (or Emotion)

       The least effective is Ethos, the most effective is Pathos. However, it is a bit short-term. We can be swayed by a powerful, plausible sales pitch (e.g. Monckton!), and change our minds on reflection.

       So Logos, which science uses, is the most effective in the long term for those willing to engage with it. Since Logos is demanding and tiring, it is difficult.

       But for an "elevator pitch", Logos is pretty much long, slow thinking, so for a quick impression, go for Pathos every time.

31626. Tom Curtis at 15:30 PM on 6 February 2015
       Kevin Cowtan Debunks Christopher Booker's Temperature Conspiracy Theory
       

       daveburton @20, first and most importantly, your comments about the phrase "dishonest adjustments" are entirely beside the point.  You completely fail to adress the substantive points I made in my comment @17, failing in particular to adress the clear evidence that there is substantial year to year variability in adjusted data, particularly in the early twentieth century.  You further fail to adress the fact that the adjustments to land data, and to SST data in the early twentieth century have opposite effects on the trend.  Your failure to adress these and other issues makes your comments about the phrase "dishonest adjustments" look like a simple, and deliberate distraction from the fact that your points have been refuted in detail, and that (apparently), you have no substantive response.

       Second, you claim to "have said nothing about 'dishonest adjustments'".  Never-the-less you are commenting on a critique of Booker's article, and Booker definitely suggests the adjustments are dishonest, calling them "scary chicanery".  You, yourself summarize Booker's article by saying:

       "Christopher Booker thinks NOAA is distorting global land temperature data to inflate reported global warming, and fan the flames of climate alarmism."

       That is, according to you Booker is saying the adjustments were made with the intent to "... inflate the reported global warming, and fan the flames of climate alarmism", ie, that it was done from dishonest motives.  As I did not indicate that it was your theory, my language was entirely justified and your attempted distraction is itself ungrounded.

31627. Tom Dayton at 14:12 PM on 6 February 2015
       Kevin Cowtan Debunks Christopher Booker's Temperature Conspiracy Theory
       

       Dave Burton, you have revealed NOAA to be profoundly incompetent indeed, because their sinister attempt to hide the explanation of homogenization was so poor that a quick internet search revealed it in several place such as the CDIAC site.  Congratulations.

31628. daveburton at 13:25 PM on 6 February 2015
       Kevin Cowtan Debunks Christopher Booker's Temperature Conspiracy Theory
       

       Tom Curtis, just to be perfectly clear, I said nothing about "dishonest adjustments."

       It is very possible to to make incorrect adjustments without conscious dishonesty, though simple error, or unrecognized bias. There's a very human tendancy for scientists to scrutinize data more critically if it is contrary to their preconceptions, than if it confirms them. That tendency can easily introduce bias in the reported results, despite everyone involved having the very best of intentions.

       NOAA used to have, on their web site, a description of how they adjusted measured temperature data based on what seemed to me like a very crude proxy for urban heat island effect: satellite observations of nighttime illumination. That material is gone from their site, now, and they've blocked archive.org from archiving such materials, and I didn't save a copy (at least I don't think so), so I don't have the details. But the procedure seemed highly dubious, to me, when I read about it a few years ago.

       That doesn't mean that those adjustments were dishonest, however.

       My point wasn't about motives. I was simply addressing the misconception that NOAA's adjustments made a negligible difference in the reported result. They don't. They make a big difference.

31629. Stephen Leahy at 13:00 PM on 6 February 2015
       Water is far more valuable and useful than oil
       

       denisaf: There is misunderstanding about water as renewable. Water does recycle but does it return to where it's needed and in an acceptable time frame? Not always. Drain a lake and it may not refill in your lifetime — where will you get your water in the meantime? The Aral Sea disaster offers an example. 

       Water scarcity is about time and place.

       Treesong2: Only a small fraction of the water in Lake Erie is renewable - the rest is the gift of the last ice age. Lake levels have been falling in recent years mainly due to warmer winters. While your toilet water may be recycled, some of it is lost through leaks and contamination (sewage sludge). 

       Toilet use is a very small part of our daily water use which is the point of the article. 

       OPOF: The article doesn't get into the impacts of climate change  - the book does.

       CBDunkerson: Desal is likely to be out of reach for most people suffering from water scarcity. 1.2 billion people today do not have access to clean water. Half the world cannot turn a tap in their home to get drinking water. Let's hope there are break throughs in desal energy/cost requirements. 

       JH: Good links. 90% of water use is to grow food. Climate change is going to make feeding ourselves much harder. 

31630. daveburton at 12:57 PM on 6 February 2015
       Kevin Cowtan Debunks Christopher Booker's Temperature Conspiracy Theory
       

       Tom Dayton, (re #15) the 900% example was intended as an illustration of the problem with using a cherry-picked subset of the full time series. It is an example of what not to do. But it is computed accurately. Seriously. It really is >900%.

       However, (re #16) I did not say that the temperature anomalies do not exhibit much short-term variability. I said that NOAA's adjustments do not exhibit much short term variability. Which is right.

       I concede, however, that when the adjustments are compared to the unadjusted temperature trend, e.g. by computing the adjustment amount as a percentage of the trend, the result is senstitive to both numbers. However, I did not pick an anomolously low right-hand endpoint to minimize the early 20th century warming. 1970 actually represented a minor peak in temperature: it was warmer than 1967, 1968, 1969, 1971 & 1972.

31631. Tom Curtis at 12:53 PM on 6 February 2015
       Kevin Cowtan Debunks Christopher Booker's Temperature Conspiracy Theory
       

       Tom Dayton @16, daveburton was incorrect (see my point 2 @17 above), but neither he nor I were talking about the simple anomaly on that point.  Rather, we are talking about the adjustments, the difference between raw and homogenized data, which also shows substantial short term variability.  Just not as much as the actual anomaly, and much less over the last 50 years.

31632. Tom Curtis at 12:51 PM on 6 February 2015
       Kevin Cowtan Debunks Christopher Booker's Temperature Conspiracy Theory
       

       daveburton @14:

       1)

       "You are correct, Tom, but his graph was for the last 114 years, and his conclusion ("why would they [bother to] do that") only makes sense if the sum of NOAA's adjustments were inconsequential. It doesn't make sense if NOAA's adjustments were only inconsequential for one cherry-picked time interval, and very consequential for the whole record."

       I indicated a couple of very substantial reasons as to why we should concentrate on the period since 1950.  Because there are substantive reasons for the choice of time period, it is not a cherry pick.  Suggesting that it is without adressing those reasons amounts to simple name calling as an argument.  However, leave that aside.

       The simple fact of the matter is that the majority of early twentieth century warming is natural in origin.  Anthropogenic factors account for approximately a third of that warming, or according to one recent analysis, effectively none of it.  This can be seen by the relative slopes of temperature and CO2 concentration in the early, and late twentieth century:

       

       More substantively, comparing model retrodictions with global temperatures shows the models substantially underpredict the global trend in the early twentieth century:

       

       (Note, the pink shaded area is the model prediction for anthropogenic plus natural forcings.)

       That discrepancy can be accounted for almost completely by reference to short term variability not included in model forcings, primarilly ENSO, although the unusual warmth in the 1940s is still not accounted for.

       So, with this knowledge in hand, your argument then becomes that the people at NOAA increased temperature trends in the early twentieth century when such increases run contrary to the AGW narative, but did not significantly increase trends in the late twentieth century where such increases would have supported the narrative.

       Expanding the analysis beyond the late twentieth century does not make the theory of dishonest adjustments any more plausible.  It just means you need to understand more background information to understand the relevance of what is happening.

       2)

       "You're right about the temperatures, Tom, but that's not what's being compared (by Dr. Cowtan, and by me). What's being compared is the temperature adjustments (i.e., the difference between adjusted and unadjusted temperatures), and they do not exhibit much short-term variability."

       Here are the difference between raw and final USHCN temperatures:

       

       Very clearly, you are wrong to claim "...they do not exhibit much short-term variability".  There is substantial short term variablity, particularly in the early twentieth century, and particularly for 1900 itself.  That is, of course, for the contiguous United States.  Unfortunately I do not know of a similar chart for the global land record, but there is no reason to think it would also lack variability from year to year in adjustments.  So while the adjustments show less short term variability than do the actual temperatures, never-the-less, they show substantial short term variability and comparisons of differences should be made using trend values.

       3)

       "SST is not air temperature, and, unfortunately, the SST data quality through most of the 20th century is even sketchier and subject to more adjustments than the land air temperatures."

       First, it would be nice if there was a more or less continuous, global record of air surface temperatures at 2 meters above sea level.  Unfortunately no such record exists, so you make use of the records you in fact have rather than pretend to complete ignorance.  Those records are, however, strongly relevant.  As anybody knows, who has lived both inland and near the sea, the thermal mass of the surface waters mean they absolutely dominate the variability in nearby air masses.  That is so even 50 km inland, let alone a mere 2 meters above the surface of the water.  Although there will be some difference in the actual values between SST and 2 meter air temperature immediately above the surface, they will not be large and they will be consistent so that trends in the former would have been reflected in trends in the later.

       Given this, I regard your exclusion of SST from the record of interest as a mere cop out.  It is particularly the case given that all Global Mean Surface Temperature records use SST data over oceans, for want of any better record to use.

       Second, the SST temperature data is in fact very extensive, although it does show some coverage lapses (as does the land record), particularly in the Southern Ocean.

       Third, while the SST data is also subject to adjustments, they are not subject to "the same adjustments":

        

       (Source)

       As you can see, while the net effect of adjustments on land has been to cool the early twentieth century relative to the late twentieth century, the net effect on SST has been the opposite.  That is, it warms the early twentieth century relative to the late twentieth century.  That is, it reduces the twentieth century temperature trend.

       So, if we look at the actual data, it does not support your dismissal, which is shown to be glib, and misleading.  Contrary to the impression you convey, combining land and SST data will reduce the global trend from 1900 more than would be the case by simply diluting the 30% land coverage with data with no trend adjustment.

       4)

       "You can't do that, Tom. It's mathematically incorrect. The percentage difference isn't a sum that you can divide by 11.5 to get the per-decade adjustment-generated percentage difference in warming, it's an average."

       Then it is a good thing that that is not what I did.  Rather, I projected the difference in adjustment over the last 50 years back over the record to 1900.  That, of course, only gives a ball park figure, and given the additional data noted at point three above, underestimates the reduction in the difference for global figures.  It is near enough, however, for this discussion.

31633. Tom Dayton at 11:05 AM on 6 February 2015
       Kevin Cowtan Debunks Christopher Booker's Temperature Conspiracy Theory
       

       Dave Burton, you are incorrect that the temperature anomalies do not exhibit much short-term variability.  For example, see the escalator graph.

31634. Tom Dayton at 10:18 AM on 6 February 2015
       Kevin Cowtan Debunks Christopher Booker's Temperature Conspiracy Theory
       

       No, Dave Burton, it is not okay to compute trends by merely connecting end points.  You need to compute a regression line.  Seriously, a 900% change?!

31635. daveburton at 09:50 AM on 6 February 2015
       Kevin Cowtan Debunks Christopher Booker's Temperature Conspiracy Theory
       

       michael sweet wrote,  You have mislabeled your graph. In the video the graph is clearly labeled NOAA Paraguay data. You have changed the label to Globally averaged Land Surface data."

       No, Michael, that graph is global. Listen to Dr. Cowtan describe it, at 3:30:
       https://www.youtube.com/watch?v=qRFz8merXEA#t=210
       He says, "We can calculate a global land temperature record using..."
       
       

       Tom Curtis wrote, "in the video Kevin Cowtan says (3:55) that "... the NOAA adjustments make only about a 3% difference to the amount of warming over the last 50 years" (my emphasis)."

       You are correct, Tom, but his graph was for the last 114 years, and his conclusion ("why would they [bother to] do that") only makes sense if the sum of NOAA's adjustments were inconsequential. It doesn't make sense if NOAA's adjustments were only inconsequential for one cherry-picked time interval, and very consequential for the whole record.

       For instance, if you compare the adjusted to unadjusted warming for the first 70 years of the graph (1900 to 1970), instead of the last 50 years, you'll find that the adjustments increased the net warming by more than 900% (from 0.025 °C to 0.257 °C).

       Of course, you're probably saying to yourself, "but that's cherry-picking!" — and you're right. But no more so than just examining the last 50 years is cherry-picking.

       Tom continued, "you have made your determination simply by comparing end points. Because of the high short term variability of temperatures, such comparisons can easilly mislead by showing atypical values."

       You're right about the temperatures, Tom, but that's not what's being compared (by Dr. Cowtan, and by me). What's being compared is the temperature adjustments (i.e., the difference between adjusted and unadjusted temperatures), and they do not exhibit much short-term variability.

       Tom continued, "it is the land only data, of which Kevin Cowtan indicates their is a 10% difference after adjustments."

       But that's only for the cherry-picked last 50 years.

       Tom continued, "That 10% is reduced to 3% by the inclusion of SST data."

       SST is not air temperature, and, unfortunately, the SST data quality through most of the 20th century is even sketchier and subject to more adjustments than the land air temperatures.

       Tom continued, [if you multiply by 30% because only 30% of the globe is land] "your 35% would reduce to approximatly 11% difference over a 115 year interval, or less than 1% difference per decade."

       You can't do that, Tom. It's mathematically incorrect. The percentage difference isn't a sum that you can divide by 11.5 to get the per-decade adjustment-generated percentage difference in warming, it's an average.

31636. John Cook at 08:39 AM on 6 February 2015
       Scott Mandia on teaching students to debunk climate misinformation
       

       Thanks for your comment - I'll be in touch, would be interesting to hear more about your course and you may be interested in our upcoming MOOC, Making Sense of Climate Science Denial, which will include a great deal of creative commons material available for educators and communicators.

31637. Tom Dayton at 08:09 AM on 6 February 2015
       Kevin Cowtan Debunks Christopher Booker's Temperature Conspiracy Theory
       

       Zeke Hausfather has an excellent post on adjustments to temperature, though at an unfortunate site.

31638. Runrig at 06:26 AM on 6 February 2015
       Lessons from Past Climate Predictions: IPCC FAR
       

       Folks,

       Further to posting my/your input over at Phys.org, Mr bell posted up this (whilst not acceding defeat).

       "Thank you Tony for your honest analysis and discussing the content of my claims. I'll pursue this at the discussion thread you provided.

       It's too bad there aren't more people on this thread with intellectual honesty, but I do appreciate yours."

       So you may well be able to take him in in person.

       PS: he has been generally polite (and always with me), except when when goaded.

       Tony

31639. Maggnum at 06:14 AM on 6 February 2015
       Lessons from Past Climate Predictions: IPCC FAR
       

       I just want to comment on the well thought out answers on this thread, with thanks. I should have thought to have brought the problem here, and thanks Tony for doing so. 

       Mr. Bell is somewhat less objective than he holds himeslf out to be. Tom. your review seems to hit the crux of the issues - Mr. Bell is using a deceptive and incomplete "analysis" as a means to call the IPCC as a whole deceptive or incompetant. I think that, in and of iteself, is enough to put his "analysis" into its proper perspective. 

       Thank you Tom for looking into it, and thank you Tony for bringing it here for review. 

31640. Tom Curtis at 04:23 AM on 6 February 2015
       Kevin Cowtan Debunks Christopher Booker's Temperature Conspiracy Theory
       

       daveburton @9 and @10, in the video Kevin Cowtan says (3:55) that "... the NOAA adjustments make only about a 3% difference to the amount of warming over the last 50 years" (my emphasis).  By comparing the range from 1900-2014, you are not checking his claims, but an entirely different claim that he did not make.  You may think this is a minor point, but in fact the key attribution statement for the IPCC is with regard to the period 1950-2010.  That is, it is with regard to (approximately) the last half century.  There are several reasons for that, one of which is the relative accuracy of the temperature record post 1950.  Consequently there are substantive reasons why the IPCC and Kevin Cowtan concentrate on the most recent 50-60 years.  

       Further, on checking your spreadsheet it becomes very apparent that you have made your determination simply by comparing end points.  Because of the high short term variability of temperatures, such comparisons can easilly mislead by showing atypical values.  To avoid this, the correct method is to determine the respective trends, and compare them directly, or if you insist on comparing end points, compare the endpoints of the trendlines.  This is particularly the case as it is future temperature trends we are concerned with.  Comparing the endpoints for 1950-2014 (14% difference by your method), 1965-2014 (10% difference by your method)  shows the effect of increasing accuracy overtime resulting in less difference between adjusted and unadjusted data, and highlights the problem with using endpoints.

       Finally, although Michael Sweet is incorrect to describe the graph as Paraguay data, it is the land only data, of which Kevin Cowtan indicates their is a 10% difference after adjustments.  That 10% is reduced to 3% by the inclusion of SST data, and we could expect a similar scale of reduction in your figure if it compared land/ocean temperature data rather than land only data.  That is, your 35% would reduce to approximatly 11% difference over a 115 year interval, or less than 1% difference per decade.

31641. michael sweet at 03:42 AM on 6 February 2015
       Kevin Cowtan Debunks Christopher Booker's Temperature Conspiracy Theory
       

       DaveBurton,

       You have mislabeled your graph.  In the video the graph is clearly labeled NOAA Paraguay data.  You have changed the label to Globally averaged Land Surface data.  Dr. Cowtan points out that such a change in the Paraguay data would only affect Global data by 3%.

       How could you make such a large error by mistake?  It appears that you are deliberately trying to mislead whoever you show your mislabeled graph.  This must be a conspiricy to defraud the public about this data.  Who is paying you to make these fradulent claims?    

       It is well known that change of time of reading and change in temperature monitoring stations can make readings this different.  The installation of Stephenson screens as described in 5 above woud cause this change.

       It is easy  to claim dramatic changes have been made when you mislabel the data.

31642. daveburton at 03:37 AM on 6 February 2015
       Kevin Cowtan Debunks Christopher Booker's Temperature Conspiracy Theory
       

       I didn't say that very well.
       
       "...had increased globally averaged land surface temperatures by 35%"
       should have been:
       "...had increased the warming seen in globally averaged land surface temperatures by 35%"

31643. daveburton at 02:53 AM on 6 February 2015
       Kevin Cowtan Debunks Christopher Booker's Temperature Conspiracy Theory
       

       Dr. Cowtan's final argument was that the adjustments were too tiny to be suspicious.  “Why would they do that?” he asks at the end of his video, meaning why would anyone commit fraud for an inconsequential difference in the result?

       However, I digitized the endpoints in the last graph which he showed in his video, and found that NOAA's adjustments had increased globally averaged land surface temperatures by 35%.
       
       35% is not inconsequential.
       
       The graph w/ comments, and a small spreadsheet with the numbers, are here:
       http://tinyurl.com/cowtan-v-booker
       
       Here's a half-size version of the annotated graph:
       
       
       

       Moderator Response:

       [RH] Adjusted image size.

31644. howardlee at 02:34 AM on 6 February 2015
       Claims that climate models overestimate warming are 'unfounded', study shows
       

       In the long view, paleoclimate work presented in the AGU14 for the Miocene suggests sensitivities at the upper end of the IPCC range. In other words, the bahavior of Earth's climate in the past does not support the idea that model-based projections are overstated. If anything they suggest the opposite. There should hopefully be a post on this coming out in a few days.

31645. swampfoxh at 01:57 AM on 6 February 2015
       Scott Mandia on teaching students to debunk climate misinformation
       

       I have been teaching a course, "Global Warming: Proof or Politics?", designed for the general public using, for classroom space, public library meeting rooms in two counties in Virginia.  I would like to correspond with skepticalscience.com people who are trying to get proper climate change information out to the public.  My email is swampfoxh@hotmail.com 

31646. KR at 01:35 AM on 6 February 2015
       Lessons from Past Climate Predictions: IPCC FAR
       

       I'll bow to Tom Curtis's far better researched answer on this one. :)

31647. Runrig at 21:57 PM on 5 February 2015
       Lessons from Past Climate Predictions: IPCC FAR
       

       Tom,

       thanks again - I've put the latest response from you here ...

       http://phys.org/news/2015-01-climate-dont-over-predict.html

       And have suggested Mr Bell call in here for more "learned" discussion.

       Oh, and if you'd care to call in on Phys.org to make comments you'd be more than welcome!

       Tony

31648. Bart at 20:30 PM on 5 February 2015
       Climate researcher Bart Strengers wins wager with climate sceptic Hans Labohm
       

       Thanks a lot for all your comments!

       Below I tried to answer most of them:

       @ranyl: I surely have considered that the CS might be higher. I just explained why the lower bound of the IPCC-range has been lowered from 2.0 to 1.5 in AR5.

       Studies of my institute (Netherlands Environmental Assessment Agency, PBL) show that a >50% change to keep the warning limited to 2 degrees, implicates a major emission reduction effort with negative emissions by the end of this century.

       If you want a bigger than 95% change, this reduction effort will be even higher. We did not study the implications of even lower temperature limits, but I think you are right this might result in a current negative carbon budget.

       @Wili: I did not write we have 0.1 degrees warming in 5 years, but that the average temperature in the period 2010-2014 was 0.1 degrees higher than the average of the 10 years before that. TonyW explains how this results in 0.15. (UAH has a linear trend of 0.14 starting in 1979 by the way). Furthermore, you are right that volcanoes can result in a ‘cold’ year and thus can have a large influence on the average of an extremely short period of just 5 years. This is precisely one of the reasons why I said in 2009 that I could lose the wager.

       @jja: Interesting publication. In the Dutch media I wrote that I think that the change the next 5 years will be warmer again than the 10 before is at least as big as 5 years ago. Aerosol emission reductions in China - as far as it is really true, given the discussion in this tread - might be another reason why this will probably be the case.

       @Paul W and Philippe: You are right there is a problem there. What I meant in 2009 is that the integral of the pdf on the left of the ‘best estimate’ of 3.0 is smaller than the integral on the right. In other words P(ECS<3.0) < P(ECS>3.0). P(ECS<3.0) is the chance that the real world ECS is lower than the best estimate and thus that the best estimate is an overestimation. And according to the same reasoning P(ECS>3.0) means that the best estimate is an underestimation. However, there are two problems here. The first is that I am not so sure anymore that the proposition P(ECS<3.0) < P(ECS>3.0) was actually true in 2009. I would love to hear your opinion on that. The second problem is that in AR5 there is no best estimate anymore, so it is actually impossible to say whether my proposition still holds. Because it was too complicated to explain this to a broader audience, I tried to make the point I did. I might have done that differently now, though.

31649. chriskoz at 10:11 AM on 5 February 2015
       2015 SkS Weekly News Roundup #6A
       

       The article about battery storage & demise of fossil fuels is very interesting. Especially the actual link to the Citigroup report therein that I repeat here:

       solar-battery-storage-socket-parity

       Important part of this analysis is the fact, as the article notes:

       Figure [therein] illustrates Citigroup’s point. It assumes a large portion of the solar output is self-consumed rather than sold to the grid, so the ‘income’ is primarily avoided electricity bills rather than energy sales.

       That's exactly what;s happening in Australia: demand for electricity drops as rooftop panel penetration grows. However, I'm not sure how they incorporated that change in consumption model in their prediction of parity. To learn more, it's worthwhile to visit (or at least watch the outcome of:
       2015 Australian Energy Storage Conference in Sydney

31650. Tom Curtis at 09:09 AM on 5 February 2015
       Lessons from Past Climate Predictions: IPCC FAR
       

       Runrig @18, I get slightly different values, particularly for the upper range as note in my prior comment.  However, given that I must judge the year by eye, and given that the reproduction of the graph shows it was a photocopy of a page, not perfectly flat on the plate, I would not argue the toss.  Two points, however.  First, Bell bases his analysis on the range of BaU through to scenario D on just one climate sensitivity value, rather than just BaU across the range of climate sensitivity values.  Second, you mention "the full range of of scenarios".  I think it is better to be more precise and mention the range of scenarios and climate sensitivities.

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