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Comments 27401 to 27450:

27401. billev at 07:15 AM on 2 October 2015
       It's a natural cycle
       

       From Time Magazine, June 24, 1974: " As they review the bizarre and unpredictable weather pattern of the past several years, a growing number of scientists are beginning to suspect that many seemingly contradictory meteorological fluctuations are actually part of a global climatic upheaval.  However widely the weather varies from place to place and time to time, when meteorologists take an average of temperatures around the globe they find that the atmosphere has been growing gradually cooler for the past three decades.  The trend shows no indication of reversing.  Climatological Cassandras are becoming increasingly apprehensive, for the weather aberrations they are studying may well be the harbinger of another ice age. 

            Telltale signs are everywhere - from the unexpected persistence and thickness of pack ice in the waters around Iceland to the southward migration of a warmth-loving creature like the armadillo from the Midwest.  Since the 1940's the mean global temperature has dropped about 2.7 degrees F.  Although that figure is an estimate, it is supported by other convincing data."  And to think, all these people had to do is talk to a "numbers guy" and he would have convinced them that what they were experiencing wasn't really what they were experiencing.

       Moderator Response:

       [PS] Please see "ice age predicted in 1970s" and comment there if you wish to dispute the article. No follow up responses to this particular comment on this thread please.

        

27402. boba10960 at 04:32 AM on 2 October 2015
       Was Broecker really the first to use the term Global Warming?
       

       Ari Jokimäki comment 8: I'm afraid my sense of time isn't as good as I wish it were. If I recall correctly, the question came up around the time that one of Broecker's books on climate change was released, but I don't recall which book. I believe it occurred before 2008, but I can't be certain.

       What I do recall more clearly is that Broecker was not concerned at that time about being credited with coining the term "global warming." In fact, at the time that he was querying his colleagues about the term's origin he was pretty certain that the term had been used previously, but he was unsure of its source. His priority has always been to inform policy makers about the urgency of dealing with warming, as illustrated so well in his "angry beast" metaphor.

       More important than the terminology, in my opinion, is that Broecker's 1975 paper presented the view of global warming held by the best informed scientists at the time. One often sees "skeptics" say that climate scientists have done a 180-degree flip-flop in their "alarmism," warning of a pending ice age in the 70's before switching to global warming in the 80's. My response to anyone who raises this flip-flop issue is to point them to Broecker's 1975 paper as evidence of the mainstream view at the time.

27403. Dcrickett at 03:13 AM on 2 October 2015
       Was Broecker really the first to use the term Global Warming?
       

       There is an unavoidable confusion in use of the term "warming" which can mean "increase in temperature" and also "addition of thermal energy". It appears to me, from personal experience and from the fascinating discussions here, that Global "Warming" refers to increasing temperature. Myself, I am becoming more fond of the addition of heat, which, among other things, renders the "Global Warming Hiatus" meaningless.

27404. r.pauli at 01:44 AM on 2 October 2015
       Was Broecker really the first to use the term Global Warming?
       

       What a great discussion of history.   Unique and dynamic times require the invention of new terms.  Language as significant, heroic action.   

27405. Ari Jokimäki at 00:22 AM on 2 October 2015
       Was Broecker really the first to use the term Global Warming?
       

       Thanks for the insider information, boba10960. I have cited a NASA page from 2008 making the claim that Broecker was the first, but did the things you describe happen before that? I'm just wondering what is the route of this becoming a popular thing to say that Broecker was the first to use the term.

       Tor B, thanks for the elaboration. I quickly checked 1959 and 1958 results from Google books for the "global warming" and didn't see much else than books with wrong publication year in Google database. So perhaps there actually are no late 1950s books using the term.

27406. CBDunkerson at 00:03 AM on 2 October 2015
       Is the fossil fuel industry, like the tobacco industry, guilty of racketeering?
       

       David Lewis, while Exxon could certainly argue that they didn't know exactly what would happen (as there was indeed still scientific debate) they could not (truthfully) argue that they didn't know the disinformation they were funding was false. After all, the campaign wasn't just, 'We do not know how bad it will get'... there was outright denial that atmospheric CO2 levels were rising, that fossil fuels were causing it, that CO2 even CAN warm the atmosphere, et cetera. Countless claims that they knew from their research were blatantly and ridiculously false.

       Indeed, the uncertainty on the science just deepens the similarity to the tobacco industry. At the time they were doing their research, it wasn't known how smoking caused cancer or how many people who got cancer did so because of smoking... just that smoking significantly increased the likelihood of cancer. Which the tobacco companies then publicly lied about.

27407. Tor B at 00:00 AM on 2 October 2015
       Was Broecker really the first to use the term Global Warming?
       

       For the record, I used Google's Ngram (1st comment above), and discounted small numbers and 'early' blips of larger ones (and therefore my using the phrase "showing up regularly" and terms suggesting "about").  The link I attempted to include that was removed identified this source. [Sorry, Rob, for creating the problem.]  Removing the small numbered hits was my lazy method of attempting to avoid chance hits such as Ari notes in Comment #8.

27408. MA Rodger at 23:09 PM on 1 October 2015
       CO2 lags temperature
       

        

       Tom Curtis @484.

       I would say your 0.2% is sound. Another person calculating this value is Tamino who arrives at 0.18% and 0.61Wm^-2 for obliquity ranging "between a minimum of near zero, and a maximum of slightly less than 0.06" and prior to albedo considerations.  My take on the www.climatedata.info is that they calculated the discal forcing (as graphed in their fig 3 that you show) but then they forgot to divide by 4 when they applied that as a global forcing to calculate the percentage, which should therefore be 0.175%.

27409. boba10960 at 22:41 PM on 1 October 2015
       Was Broecker really the first to use the term Global Warming?
       

       Just to be clear, Wally Broecker did not promote himself initially as the person who coined the term “global warming”. Years ago he was asked by a reporter if his 1975 paper, quoted in this article, was the first use of the term. He was unsure, so he asked several of his colleagues, including me, if anyone was aware of a prior use of the term. As far as I know, no one did a rigorous search like that performed by Ari Jokimäki, but none of the people queried by Broecker was aware of prior use of the term. Nevertheless, largely as a consequence of Broecker’s query, it became conventional to ascribe the coinage of the term “global warming” to Broecker’s 1975 paper. I’ve been guilty of that myself. Now, thanks to this post, I won’t make that mistake again.

27410. Tom Curtis at 21:26 PM on 1 October 2015
       CO2 lags temperature
       

       MA Rodger @483, thank you for drawing my attention to this graph:

       

       That shows an approximate 2 W/m^2 total range of fluctuation, but is calculated for TOA insolation.  Converting for current albedo brings that down to 1.4 W/m^2, or approx three times my calculated range.  The key point is that is still a tiny forcing.  If total anthropogenic forcing since the pre-industrial could be limited to 1.4 W/m^2, global warming would not be a problem.  Conversely, if we asssume that the temperature differences between glacial and interglacial were due to a feedback on the global annual average value (calculated as 1.4 W/m^2), then the climate sensitivity would be approximately 13 C per doubling of CO2.

       Setting that aside, however, I notice that Chis Colose calculates a similar value to mine:

       "Eccentricity is the only Milankovitch cycle that alters the annual-mean global solar insolation (i.e., the total energy the planet receives from the sun at the top of the atmosphere). For the mathematically inclined, the annually-averaged insolation changes in proportion to 1/(1-e²)^0.5, so the solar insolation increases with higher eccentricity. This is a very small effect though, amounting to less than 0.2% change in solar insolation, equivalent to a radiative forcing of ~0.45 W/m² (assuming present-day albedo). This is much less than the total anthropogenic forcing over the 20th century. However, eccentircity does modulate the precessional cycle, as we shall see."

       John Baez finds only a 0.167% range (or 0.4 W/m^2 with current albedo):

       "Now, the first important thing to realize is this: it's not obvious that Milankovitch cycles can cause glacial cycles. During a glacial period, the Earth is about 5°C cooler than it is now. But the Milankovitch cycles barely affect the overall annual amount of solar radiation hitting the Earth!

       This fact is clear for precession or changes in obliquity, since these just involve the tilt of the Earth's axis, and the Earth is nearly a sphere. The amount of Sun hitting a sphere doesn't depend on how the sphere is 'tilted'.

       For changes in the eccentricity of the Earth's orbit, this fact is a bit less obvious. After all, when the orbit is more eccentric, the Earth gets closer to the Sun sometimes, but farther at other times. So you need to actually sit down and do some math to figure out the net effect. Luckily, Greg Egan did this for us—I'll show you his calculation at the end of this article. It turns out that when the Earth's orbit is at its most eccentric, it gets very, very slightly more energy from the Sun each year: 0.167% more than when its orbit is at its least eccentric."

       Baez also shows the derivation of the result.

       Even the Washington Edu slide you link to gets the percentage change about right (0.18%), but messes up in calculating the change in forcing that results.

27411. MA Rodger at 19:38 PM on 1 October 2015
       CO2 lags temperature
       

        

        

       Tom Curtis @481.

       The figures I have read elsewhere do conform with your calculated 0.2% for the global annual insolation variation (resulting from obliquity which is varying from roughly zero to a little above 0.06). Mind, the graphic tatelyle was linking to above (as @479) originates from the web-page here that for some reason gives the figure for global annual insolation variation a lot higher at 0.7% although the graphic they show for this (their fig 3) does look to be the right shape. Still, they aren't the only folk to get their numbers wrong on this matter. This Washington Edu slide show manages to miss off the decimal point in their insolation figure, twice, giving a 0.18% change in insolation from obliquity as a rather toasty 5Wm^-2.

27412. ryland at 19:28 PM on 1 October 2015
       Is the fossil fuel industry, like the tobacco industry, guilty of racketeering?
       

       You're quite correct KR I am misinterpreting (once again) in Bizzaro fashion by typing CO2 instead of NoX.  My error for not cxhecking what I had written.

27413. Ari Jokimäki at 17:07 PM on 1 October 2015
       Was Broecker really the first to use the term Global Warming?
       

       That 1890 case sensitive hit is "The Sanitarian" by Agrippa Nelson Bell. It contains the search phrase only once, and it is this:

       "Cholera in Persia, 60. Civic Cleanliness, Coleman, 3. Climate, Change of, 356. Clothing in its Relations to Hygiene, Hibberd, 139. Cocaine Poisoning, Ammonia in, 87. Codeine, 380. Coffin Nails, 147. Colds, Acute and How to Treat them, 382."

       This is one bad aspect of Google searches, the exact phrase search matches also those phrases that have punctuation marks in them.

27414. denisaf at 16:35 PM on 1 October 2015
       Is the fossil fuel industry, like the tobacco industry, guilty of racketeering?
       

       There is no doubt that fosil fuel industry have employedsome mal practices to ensure their profitability  by maintaining demand. But the consuming public provide the demand so they can enjoy their materialistic life style. What will cause the masses to stop driving their cars and flying hither and thither? What wiil get them to turn off their TVs, airconditioning and heating?

       Moderator Response:

       [Rob P] This is the logical fallacy known as a False Dichotomy, or Black or White fallacy.

       A technologically-advanced society requires energy, but there is no requirement that this be derived from fossil fuels. That a truly advanced society would eschew fossil fuels, given the ultimate consequences of burning them (global warming & ocean acidification), is a persuasive argument. 
       
       If you wish to engage in a genuine discussion, then please do so. Further trolling will likely result in your comment being moderated.

27415. Tom Curtis at 16:28 PM on 1 October 2015
       It's a natural cycle
       

       billev @12, what you "still see" has little bearing on what the data shows.  It is fairly plain that you are applying a double standard.  Elsewhere, you said the GISS data "... also could be indicating another pause beginning about 2000 ...".  If we look at that data using the Skeptical Science trend calculator we find the following trends: 

       1970- 0.174 +/- 0.029 C/decade

       2000- 0.132 +/- 0.124 C/decade

       If we take the difference, and add the uncertainties in quadrature, we find the difference in the trend, and the uncertainty of that difference:

       Difference: 0.042 +/- 0.127 C/decade (0.66 σ)

       As you can see, the difference in the trend is much smaller than uncertainty, meaning there is minimal evidence supporting your view that the data "could be indicating" another pause.  However poor the evidence, however, it sets a benchmark of what you consider sufficient evidence to entertain that possibility.

       In the same post, you also said the data "shows me a pause in temperature rise from ... from the mid 1940's until about the mid 1970's".  Again, we find the trends and uncertainties for the relevant periods: 

       1910-1945 0.136 +/- 0.045 C/decade

       1910-1970 0.06 +/- 0.022 C/decade

       1945-1970 0.008 +/- 0.07 C/decade

       Again, taking the difference and summing uncertainties in quadrature, we find:

       Difference ('10-'45): 0.128 +/- 0.083 C/decade (3.08 σ)

       Difference ('10-'70): 0.052 +/- 0.073 C/decade (0.84 σ)

       The 3.08 standard deviation difference in trend is certainly sufficient to infer a change in trend, given that we accept those trends as being the underlying trends.  That, however, is in dispute, and it is dubious that the 0.84 standard deviation difference between the 1910-1970 trend and the 1945-1970 trend is sufficient to infer a difference in trend.  The important point here, however, is that you do infer a change in trend.  Ergo, you consider that 0.84 standard deviation difference to be sufficient to infer that there is a change in trend.  You certainly consider the 3.08 standard deviation differenc to be sufficient to make that inference.

       Being fair, you may think that difference between the 1910-1945 and the 1910-1970 trends is sufficient to infer a different slope for the shorter period.  So, again checking the trends, taking the difference and adding uncertainties in quadrature we get:

       1910-1945 0.136 +/- 0.045 C/decade 

       1910-1970 0.06 +/- 0.022 C/decade

       Difference: 0.076 +/- 0.05 C/decade (3.03 σ)

       So, a 3.03 standard deviation difference, which we again can use as a benchmark for justifying your argument.  Note, however, that if you use this reasoning, you have to accept that just one leg exceeding 2 standard deviations is sufficient to break a longer trend into two shorter trends in your analysis.

       So, what then of the argument that the trend from 1910-1945 should be broken into two shorter periods, the first with a flatter and the second with a steeper trend.  Again, data and differences are calculated:

       1910-1945 0.136 +/- 0.045 C/decade

       1933-1945 0.421 +/- 0.165 C/decade

       Difference ('10-'45): 0.285 +/- 0.171 (3.33 σ)

       Difference ('10-'33): 0.329 +/- 0.185 (3.56 σ)

       Quite clearly, the trend from 1933-1945 is statistically significant.  More importantly, the difference in trend between 1933-1945 and either 1910-1945 or 1910-1933 is larger than any other difference considered above.  Further, it is larger, measured in standard deviations, than any of the trends considered above.  Ergo, for you to consider there to be pause from 1945-1970 but not insist that the period from 1910-1945 to be composed of two shorter periods having two different trends applies a double standard.  Specifically, you consider evidence stronger than that which convinces you of the 1945-1970 pause to be insufficient to convince you that the period 1910-1945 should not be modelled as one continuous trend.

       The case for a downward trend from 1945 is not as strong, primarilly due to the short period (1945-1950).  Despite that, the trend verges on statistical significance (see below), and the trend difference is the largest yet examined.  Somebody who considers that the post 2000 data "could indicate another pause" has no basis on which to consistently reject that downward plunge.  Nor can anybody insisting on a distinct 1945-1970 trend consistently insist on a requirement of statistical significance for both the upward and downward trends for the 1940s spike.  The data shows that the 1945-1970 and the 1950-1970 trends are stastically indistinguishable from the 1910-1970 trend; and that the 1933-1945 trend is statistically distinguishable from all preceding and following trends.  The most economic way to parse that data is to assume a persistent background trend over the first three quarters of the twentieth century interupted by a sharp upward trend from the mid 30s to mid 4s, after which temperatures relaxed back to the background trend value.  

       1945-1970 0.008 +/- 0.07 C/decade

       1950-1970 0.031 +/- 0.099 C/decade

       1945-1950 -0.514 +/- 0.559 C/decade

       Difference ('45-'70): -0.522 +/- 0.563 C/decade (1.85 σ)

       Difference ('50-'70): -0.545 +/- 0.568 C/decade (1.92 σ)

        

27416. Tom Curtis at 16:14 PM on 1 October 2015
       Was Broecker really the first to use the term Global Warming?
       

       Treesong2 @4, the term "global warming" only appears in the title of Broecker's article.  In the abstract, he writes:

       "If man-made dust is unimportant as a major cause of climatic change, then a strong case can be made that the present cooling trend will, within a decade or so, give way to a pronounced warming induced by carbon dioxide. By analogy with similar events in the past, the natural climatic cooling which, since 1940, has more than compensated for the carbon dioxide effect, will soon bottom out. Once this happens, the exponential rise in the atmospheric carbon dioxide content will tend to become a significant factor and by early in the next century will have driven the mean planetary temperature beyond the limits experienced during the last 1000 years."

       Clearly he is happy to use "a pronounced warming" and "global warming" synomomously.  That being the case, your argument applies as much to his article as to any prior.  The fact is that terms in a language are very rarely introduced by definition.  Rather, a standard usage will get frequent application to a particular context, and by familiarity come to name the phenomenon in that context specifically.  Thus, we will have a large number of instances of people referring to the "global (warming trend)" that currently exists, and is induced anthropogenic factors.  As a result, people will come to understand by "global warming" the current warming trend induced by anthropogenic factors, ie, "Global Warming".  Without that later linguistic development, we would interpret Broecker's use as "global (warming trend)" no less than any of the others.  It follows that the others have a greater claim to "first use of the term" even though they did not use it with its current meaning.

       Note that if we insist the "first use" be a use which clearly uses the modern sense, then a sorites paradox arises as usage will gradually shift from the earlier to the later.

        

       With regard to the n-gram, using a case sensitive filter, the first appearance of "Global Warming" is in 1890.  It occurs again in 1961, 1969, and 1975, occuring every year thereafter.  It becomes common in 1989, but remains a distinct minority usage relative to "global warming".  Arguable, any capitalization of the term other then in titles represents a modern usage. 

27417. Ari Jokimäki at 15:54 PM on 1 October 2015
       Was Broecker really the first to use the term Global Warming?
       

       The 1776 "climate change" hits in Tom Curtis' search at first look seem to be genuine, excellent!

27418. David Lewis at 15:51 PM on 1 October 2015
       Is the fossil fuel industry, like the tobacco industry, guilty of racketeering?
       

       Just because Exxon scientists describe their own climate research as "in accord with the scientific consensus" of the time, it doesn't mean that "the world's largest oil company accepted and concurred with the scientific consensus on human caused global warming". There needs to be evidence that indicates what the senior executives thought.

       Besides, the "scientific consensus" then wasn't as solid as it is now.

       The Exxon scientists summed things up like this:

       "a general consensus regarding the likelihood and implications of a CO2 induced greenhouse effect will not be reached until such time as a significant temperature increase can be detected".

       That this was true in 1982 was clearly shown by Hansen in 1988 when he made his big splash on front pages all over the world over his statement to Congress that he was 99% certain that the greenhouse was here.

       The debate in 1982 was far less potent than it is today.

       Consider this article.  Hansen himself has been circulating this recently, i.e. in a July 2015 communication.

       In the article it is made clear that there were a number of prominent climate scientists unwilling to back Hansen in public on this even as late as 1988.

       Its one thing to build a case that Exxon contributed heavily to the campaign to minimize public understanding of what climate scientists have discovered. But why claim Exxon knew what would happen way back when, when, way back then, a significant number of climate scientists themselves were reluctant to take a such a position in public?

27419. Ari Jokimäki at 15:48 PM on 1 October 2015
       Was Broecker really the first to use the term Global Warming?
       

       Some time ago I did the same analysis for "climate change" and "climatic change". First genuine use of "climate change" that I could find was by Willis (1925):

       Willis R (1925) Physiography of the California coast ranges. GSA Bulletin 36(4):641–678. doi:10.1130/GSAB-36-641.

       First genuine use of "climatic change" that I could find was by Mayer(1856):

       Mayer B (1856) Observations on Mexican history and archaeology: With a special notice of Zapotec remains, as delineated in JG Sawkins’s drawings of Mitla 9(4), Smithsonian Institute, Washington DC.

       I checked the Google book search Tom Curtis mentioned, and the 1869 book mentioning global warming seems to be faulty finding. I repeated the Google book search only for the year 1869 and I get a book by Sir Norman Lockyer which indeed seems to be from 1869. However, when you look at the actual findings from the text, you see that global warming has been found from somewhere that clearly is more modern text. I cannot check further as the search results don't give you an option to open the findings further. So, it seems to me that Google book search returns an 1869 book based on search hits from some other book which is more modern.

       This is the same thing I noticed when I was digging on this with Google Scholar: you don't usually find the truth simply by looking search hit numbers, you have to dig the search results to see which hits are genuine and which hits are not (I wrote an article on this a while back).

       That being said, it would be interesting to see what are the late 1950s books in Tor B's search results. Also, what was the search engine as the resulting numbers agree quite well with my numbers? I know that there are more accurate search engines than Google, but for scientific searches those engines usually require subsription and are limited in their historical paper content.

27420. KR at 13:23 PM on 1 October 2015
       Is the fossil fuel industry, like the tobacco industry, guilty of racketeering?
       

       Ryland - Note that CO2 emissions are directly tied to mileage, and that the deceptive VW software emphasized mileage over emissions when not being directly tested. They did find on mileage but are horrible polluters with other gases. 

       The software scamming resulted in greatly increased nitrous oxide and particulates, not increased CO2. You seem to (again) be misinterpreting in Bizzaro fashion.

27421. Treesong2 at 12:49 PM on 1 October 2015
       Was Broecker really the first to use the term Global Warming?
       

       I would argue that the examples in all the pre-1971 quotations except for Fletcher (1969) should be parsed as global (warming trend), not (global warming) trend, so 'global warming' as a term, rather than an incidental collocation, only goes back to 1969. The Google hits mentioned by Tom Curtis may take it back further, of course.

27422. ryland at 11:35 AM on 1 October 2015
       Is the fossil fuel industry, like the tobacco industry, guilty of racketeering?
       

       Add to the list the automotive industry.  It seems that since 2008 the fall in CO2 emissions from vehicles is about 50% less than has been claimed.  Scamming the numbers just adds more to the negative aspects of the climate change debate.  

27423. billev at 08:54 AM on 1 October 2015
       It's a natural cycle
       

       Sorry, Tom.  I still see a pause in warming from about the mid 1940's until the mid 1970's regardless of the addition of a yellow trend line from GISS.  I assume that  a chart of the type of the NOAA and GISS charts is designed to give the viewer information in an easy to understand format.  That format shows me the  break in warming I just mentioned.

27424. Tom Curtis at 06:48 AM on 1 October 2015
       CO2 lags temperature
       

       tatelyle @478, from the wording of your comment, I assume you are making the error discussed here.  For what it is worth, a feedback is positive if its incremental gain (g) is positive.  Because feedbacks are iterative, ie, they respond to temperature increases resulting from feedbacks just as much as they respond to those from forcings, the final response of a feedback (f) is given by the formula, f=F/(1-g), where F is the Forcing, and f and g have already been defined.  A simple look at that formula tells you that feedbacks do not "runaway" unless g is greater than or equal to 1, which is not the case.

       You may, however, by raising the issue that atmospheric CO2 concentration can be a feedback on temperature, and temperature is a feedback on atmospheric CO2.  Independent of the factors discussed by Rob P, CO2 concentration increases as a linear function of temperature, all else being equal.  In contrast, global temperature increases with the log of CO2.  That means that, all else being equal, the CO2 increase loop will quickly self damp.  You would require the CO2 concentration to increase exponentially with temperature to get a runawy effect (until oceanic CO2 was effectively exhausted). 

27425. Tom Curtis at 06:29 AM on 1 October 2015
       CO2 lags temperature
       

       tatelyle @476, the Earth is effectively a sphere.  No amount of rotations, changes of tilt or axial wobbles will change the total amount of energy recieved by a sphere by radiation from a distant source.  All that will change is the location on the surface that recieves the insolation.  It follows that while changes in obliquity and precession may change the insolation in July at 65 degrees North substantially, it cannot change the total amount of energy recieved by the Earth anymore than the day night cycle can.  Thinking that it can is just a more subtle version of the error that thinking that just because it happens to by night time at my current location, therefore the global average energy recieved from the Sun at the moment is zero.

       In contrast, changes in eccentricity can change the annual average insolation.  That is because with a more eccentric orbit, the Earth spends more time at a greater distance from the Sun.  That more than compensates for the briefer time spent closer to the Sun.  This effect, which is the only Milankovitch cycle that actually changes global, annually averaged insolation, is very small.  If my calculations are correct, the maximum change is of the order of 0.2% or about 0.5 W/m^2, and is typically much smaller than that.

       That being the case, milankovitch cycles can only significantly effect global temperatures if there are, not just feedbacks, but differences in th feedbacks that depend on location and season.  If the winter feedback to the change in insolation in the NH was as strong as the summer feedback, milankovitch cycles could not result in glaciations.  Likewise, if the NH feedback was as weak as the SH feedback, the milankovitch cycles could not result in glaciations.

       And of course, if there were no feedbacks, there could be no variation in the strength of feedbacks based on latitude and season.

       As it happens, the feedback that shows the most seasonal and latitudinal difference is the albedo feedback.  This is, primarilly because in the NH, lower latitude snow falls on land and can accumulate, wheras in the SH it falls on water and melts.  As a result, the NH albedo feedback is stronger.  Further, because of seasonal variation in insolation, the albedo feedback is also seasonal, being stronger in the summer than in the winter.  That means that an albedo feedback by itself could, in principle, induce glaciations from milankovitch cycles.  In practice, however, the size of the albedo feedback is fairly well known from knowledge of the size of glaciation.  It turns out to be about half of what is needed to actually explain the temperature variations.  The total temperature variations can be fully explained only by assuming an additional, greenhouse feedback.  As that feedback is predicted by radiative theory in any event, it would be obtuse to insist that it does not exist, thereby requireing a new radiative theory (which has not been supplied by the "deniers") and that we add significant complications to our theory of milankovitch cycles to make room for this non-existent new radiative theory.

27426. Tom Curtis at 05:28 AM on 1 October 2015
       Was Broecker really the first to use the term Global Warming?
       

       I do not know what source Tor B reffers to, but google n-gram shows "climactic change" first appearing in books in 1942; "climate change" first appearing in 1776 and becoming increasingly popular after the 1960s, before skyrocketing in use from the late 1980s; and "global warming" first occuring in 1869, becoming increasingly popular from 1977 onwards, before skyrocketing in the late 1980s as well.

       On a related myth, "climate change" was initially more popular, and has been the more popular of the two terms, "climate change" and "global warming" since 1994 (significnatly so since 1996).  "Global warming" was the most popular only from 1990 - 1993.

27427. rocketeer at 05:26 AM on 1 October 2015
       Was Broecker really the first to use the term Global Warming?
       

       Semantics aside, if you look at the global temperature graph published in Broecker's letter, It predicts the global average temperature in 2015 to within 0.1C as best as I can measure it.  Not bad for a napkin-quality projection.  I also find it interesting to compare this plot wiht the Berkeley BEST reconstruction.  Shockingly similar.

27428. Tor B at 03:29 AM on 1 October 2015
       Was Broecker really the first to use the term Global Warming?
       

       I know this is in ‘English language books’ and not ‘scientific papers’, but

       show the term “climatic change” showing up regularly since about 1850, “climate change” since the 1920s and “global warming” since the late 1950s. “Climatic change” usage peaked in the 1990s, and “global warming” and “climate change” took off in 1986. In British English, “Climate change” became significantly more used than “global warming” after 1992.

       Moderator Response:

       [Rob P] - The string you pasted, and now edited out, was breaking the page layout.

27429. ranger001 at 02:43 AM on 1 October 2015
       Eocene Park: our experiment to recreate the atmosphere of an ancient hothouse climate
       

       Question: Since we don't really understand why the Eocene Epoch cooled could it be that global warming of the Earth will cool again due to the same factors that made the climate cool after the Eocene?

27430. PhilippeChantreau at 01:08 AM on 1 October 2015
       CO2 lags temperature
       

       tatelyle, you're talking about a runaway warming or cooling, which can happen only if the feedbacks are greater than 1. It is obviously not the case. See the "positive feedback means runaway warming" post, use the search engine.

27431. sailingfree at 00:21 AM on 1 October 2015
       Temp record is unreliable
       

       Deniers use the arguement that the data are fudged to cast doubt on the rising temperatures.  This acticle should show Zeke Huasfather's work, that shows that the raw data has MORE warming, that because of adjustments over the oceans, the estimate of global warming are LESS than the raw data.

27432. MA Rodger at 00:19 AM on 1 October 2015
       CO2 lags temperature
       

       The graphic which tatelyle was trying to post @477 is below.

27433. tatelyle at 00:11 AM on 1 October 2015
       CO2 lags temperature
       

       And other question, if I may.

       If the world warms, and increasing CO2 acts as a positive feedback, why does the temperature eventually stop increasing, and reverse? Surely more CO2 means ever increasing temperatures.

       Especially as Milanokovitch cycles are not very influential, and need a feedback, as many commentaters have said here.

       Conversely, when the world cools and reducing CO2 is less able to warm the world, why does the temperature not continue cooling and end in a snow-ball Earth?

       Surely a strongly positive feedback CO2 would be very unstable, leading to runaway temperatures both ways. But this is not what we see, because temperatures are tightly controlled withing 10ºc.

       Thanks

       Moderator Response:

       [Rob P] - The flaw in your reasoning is the assumption that CO2 would keep increasing. The leading hypothesis is that carbon stored in the Southern Ocean is released by warming. Once that ocean carbon store is exhausted, no more extra CO2 is reaching the atmosphere. So no more push in the direction of warming. 
       
       There is a recent paper that seems to be making a stronger case for this hypothesis: Southern Ocean buoyancy forcing of ocean ventilation and glacial atmospheric CO2. Here's some slides from a lecture given by the papers authors. 

27434. tatelyle at 20:23 PM on 30 September 2015
       CO2 lags temperature
       

       Let me see if I can make that graph display properly:

       [img]https://www.cabrillo.edu/~rnolthenius/climate/Denialists/D-Ruddiman/milak&temp.jpg[/img]

27435. tatelyle at 20:21 PM on 30 September 2015
       CO2 lags temperature
       

       The article states that CO2 is a feedback that assists Milankovitch cycle warming / cooling.  Many commentaters here have also stated that Milankovitch influences are weak, and need a feedback to have any effect on climate.  Can someone explain why?

       The following graph is of Milankovitch forceing changes in the all-important high latitudes, and they are up to 100 wm2, or 25% of the average insolation strength.  In what way is this large change in insolation 'insignificant', requiring a feedback to assist it?

        

       https://www.cabrillo.edu/~rnolthenius/climate/Denialists/D-Ruddiman/milak&temp.jpg

        

       Moderator Response:

       [Rob P] - See this post: Milankovitch Cycles, by Chris Colose.

27436. One Planet Only Forever at 13:07 PM on 30 September 2015
       Is the fossil fuel industry, like the tobacco industry, guilty of racketeering?
       

       In 1987, about the time of the 'change of mind' of the leadership of Exxon, the UN published "Our Common Future". It presents in detail many of the ways that development had been headed in an ultimately unsustianable and increasingly damaging direction, including the problem of excess CO2 from burning fossil fuels.

       The following explanations of he unacceptable irresponsible developments are presented in the document: "We act as we do because we can get away with it." "Future generations do not vote; they have no political power or financial power; they cannot challenge our decisions."

       The Exxon executives and investors may have felt threatened by the document and the actions towards reducing CO2 emissions which were mentioned as a needed change. Or they could have been encouraged by the awareness that they could get away with behaving less acceptably.

       Either way, those executives and those investors all those years ago would be the ones to remove wealth from and put in jail. Which is proof positive that deliberately irresponsible cheaters can and do prosper in the democratic free-market (and they also prospered in communist ruled nations and in dictatorships). Those people gamble that they will get away with what they want without being caught and penalized, and even if they are caught they could consider that they had a better time for several years that others will never ever get to have (in other words they may consider themselves to be the winners even if they are caught).

        

27437. swampfoxh at 10:02 AM on 30 September 2015
       10 Things We Learnt From Reddit About Understanding Climate Change
       

       A risk of failure in promoting actions mitigating climate change involves, especially, the Christian religion's belief in two central dogmas: 1.  The idea of the Second Coming and its corrollary belief that we are in the End Times. 2.  The notion that God is in control of everything and he surely will not harm his beloved.  Christians recognize that "bad things happen to good people", but it doesn't "happen to everybody and it surely wouldn't happen to me if I remain sin free and obedient to my Lord."  The recent Papal expression on climate change is, as usual, not enough to change the hearts and minds of most Christians, so how do we handle this problem?  It might be easier if the majority of the Christian world lived in Third World countries where political and economic power is (relatively) inconsequential, but they don't.

27438. Alexandre at 06:25 AM on 30 September 2015
       Is the fossil fuel industry, like the tobacco industry, guilty of racketeering?
       

       This deserves a huge lawsuit against Exxon.

27439. william5331 at 01:45 AM on 30 September 2015
       Drought stunts tree growth for four years, study says
       

       Perhaps it takes that long to recharge the water table that the trees access.

27440. One Planet Only Forever at 23:36 PM on 29 September 2015
       Climate change set to fuel more "monster" El Niños, scientists warn
       

       grindupBaker,

       The Denial 101 content includes presentations of other factors that significantly affect the GMST like volcanic releases, and not just the number or volume of release but how high the volcanic gases go.

       The amount of such volcanic cooling may be skewing the trends you are looking at. The amount of volcanic cooling was particularly low during the 1997/98 El Nino event.

27441. cleanshirt at 21:25 PM on 29 September 2015
       It hasn't warmed since 1998
       

       Hi, The link to the ECMWF analyis of the HadCRUT data is broken. Any chance of a link to this study? Have Googled but can't find anywhere. 

       Moderator Response:

       [DB] An archive copy of the study can be found here.  I've also updated the rebuttal with this same link.

27442. Tom Curtis at 19:29 PM on 29 September 2015
       So what did-in the dinosaurs? A murder mystery…
       

       grindupBaker @92, the "ejecta" consists of the rock ejected from the crater by the impact.  Viewed logically, and given the size of the impact, at least some of the ejecta must have escaped to space, ie, achieve orbital velocity.  That being the case, then some portion of the ejecta must have acheived a just suborbital velocity with the result that it would have been deposited very distant from the crator, and hence logically, ejecta should be found world wide.

       In fact, geologically, the Cretaceous-Tertiary (K-T) boundary is characterized an iridium enriched layer containing micro-tektites:

       

       If I remember correctly, this K-T layer was first found in Italy, but has been found world wide:

       

       I had not thought about the red-hot aspect of the ejecta before.  Certainly while following a sub-orbital trajectory the micro-tektites would not have significantly cooled (radiative cooling being fairly inefficient), but I had mostly assumed they would be quenched by the atmosphere.  Turns out that is not so.  This paper, for example, suggests previous estimates of the associated heat pulse to have been overstated, the pulse only being "... >5 kW/m2 for a few minutes" which "... may have been sufficient to ignite localized fires and kill fauna lacking temporary shelter".  So red hot ejecta, and very unpleasant is a best case.  I do not know where the consensus on that debate has settled (if it has formed at all).

27443. grindupBaker at 17:07 PM on 29 September 2015
       So what did-in the dinosaurs? A murder mystery…
       

       I disagree with "a near-global rain of red-hot ejecta" in the posting. I'd like to see the physics in the paper about that. I'm assuming that "ejecta" means lava, if it means ash or gas then it really should say that. I scale Earth 5,000,000:1 in my ponderings because it's a handy 100" dia. that fits my kitchen and bashes only a modest hole to 4" about drywall ceiling. Ocean lithosphere 0-3/8" thick around that liquid interior rock an iron core. Land plates to 2-1/4" thick but almost all <3/4" thick. Ocean water 1/20" thick. Troposphere 1/8" thick at equator.

       Chicxulub rock 1/13" dia. (a Tapioca grain) hits my Earth ball that's filling half my kitchen. How on Earth (I mean literally) does that cause a "rain of red-hot ejecta" tapioca bits to land way around the other side unless they fly our to my fridge (which is near the Moon) and bounce back ? I think this whole raining of this and that has become wildly exaggerated beyond the vaporous cloud of ash & nasty gases thaht doubtless drift in a very leasurely fashion around my kitchen Earth ball towards my sink.

27444. grindupBaker at 15:15 PM on 29 September 2015
       Climate change set to fuel more "monster" El Niños, scientists warn
       

       Somebody at sks 1-2 years ago plotted GMST with differing symbols for the El Nino, La Nina & ENSO-neutral years. I looked at it a bit and it raised a question (at the end of this).

        

       If you plot the El Nino years only, which are 1966, 1969, 1973, 1977, 1978, 1980, 1987, 1995, 1997, 1998, 2003, 2005, 2007, 2010 you clearly see a warming trend of 0.20 degrees / decade 1966-2010

        

       If you plot the La Nina years only, which are 1967, 1968, 1971, 1974, 1975, 1976, 1985, 1989, 1991, 1996, 1999, 2000, 2001, 2008, 2009, 2011, 2012 you clearly see a warming trend of 0.16 degrees / decade 1967-2012

        

       If you plot the ENSO-neutral years only (middling between La Nina & El Nino) which are 1970, 1972, 1979, 1981, 1986, 1988, 1990, 2002, 2004, 2006, 2013 you clearly see a warming trend of 0.16 degrees / decade 1970-2013

       (I skipped El Chichon, Mt. Pinatubo, Mt. Hudson years 1982-4, 1992-4)

        

       The "clearly see" above means I eyeballed it, no LSQ fitting software. Are El Nino years "pulling away from" La Nina & ENSO-neutral like they seem to be ? If so, is this known & expected from the increase in shallow (well-mixed & thermocline) OHC ? It looks tentatively as though El Nino years might have accelerated to 0.23 degrees / decade since 1990 but there are few points and no straight-line trend has a good fit so it'll need many more El Nino years to see a clear trend there. Can anybody inform whether an increasing difference in GMST between El Nino & ENSO-neutral years is expected (or just my old eyes) ?

27445. grindupBaker at 15:02 PM on 29 September 2015
       Climate change set to fuel more "monster" El Niños, scientists warn
       

       Wol @2 Ogemaniac @3 Tom Curtis @5 But but we counter the 0.00 warming 2016-2032 gambit with the warming 2019-2032 defence (at least, you do. I could counter in a seance). I've been doing it since I saw Monckton's (?) hoot at WUWT. It's +0.00/decade GMST 1996-10 to  2014-10 (WUWT) but then it's +0.12/decade GMST 1999-02 to 2014-10 (moi). Since 1999-02 is more recent than 1996-10 this shows clearly that "global warming" has increased since 1996-10 and furthermore 1.2 degrees / 0.0 degrees = an infinite rate of increase. I love this nonsense that they do. Science gets really tedious with lots of "studying" and "analysis" and "thinking" and stuff, but this entirely other stuff is great fun. 

27446. chriskoz at 07:12 AM on 29 September 2015
       Drought stunts tree growth for four years, study says
       

       How does this new study affect the paleo-dendrology temp reconstructions? We know dendro reconstructions of mountain pines show a famous "decline" since 1960s, that was later explained by experts as possible CO2 fertilisation effect. Can droughts also affect ring densities, i.e. temp proxies? Or is the effect too short lived and everaged over many samples so that long term ring density data is not affected?

27447. CBDunkerson at 04:55 AM on 29 September 2015
       Climate's changed before
       

       RayfromNY, your proposals 1 & 4 would have neglible impact on emissions and seem unlikely to happen. We'll switch to electric vehicles long before such 'lifestyle' changes would ever be approved.

       Proposal two doesn't specify where all this organic garbage would go once you banned it from landfills... and would again have virtually no impact on global warming.

       I'm all for some variation of proposal three, though it would only be a stopgap measure.

27448. theldsthinker at 20:43 PM on 28 September 2015
       Scientists Respond To Tol’s Misrepresentation Of Their Consensus Research
       

       Even if 55 percent of climate scientists accept the global warming theory, that is still high enough for us to take it seriously.  However, I find it funny that science deniers can´t make a good list of climate researchers that disagree with the basics of the global warming theory. 

27449. Tom Curtis at 19:41 PM on 28 September 2015
       Climate change set to fuel more "monster" El Niños, scientists warn
       

       Rob P inline @6, 72-73 was not a super El Nino based on either the SOI (first graph) or MEI (second graph), although 82-83 certainly was:

       

       

       jyh @6, while concern about temperature increases due to global warming inflating ENSO indices is a reasonable concern, it is not relevant to either the Southern Oscillation Index (SOI) and or the Multivariate ENSO Index (MEI).  In particular, the SOI is an index of the air pressure difference between Tahitii and Darwin.  This in turn relates causally to the strength of the trade winds, which in turn relate causally to the El Nino/ La Nina oscillation.  Because the SOI is a temperature measure, it is not going to be inflated by the impact of global warming.

       The MEI is a conjoint index of six variables, two relating to temperature, two relating to wind velocity, and the others relating to air pressure, and to cloudiness respectively.  However, even the temperature indices used are measures of the variability of tropcial sea surface (or air) temperatures over the entire tropical Pacific.  As global warming will effect the entire area approximately equally, it will not show up in the measure of variability.  Ergo, quite appart from the dilutting effect of the other four indices, the MEI will not be distorted by the effects of global warming.

       Having said that, it is not clear that the current El Nino will be a super El Nino.  According to the MEI (and purely temperature based indices), it already is.  Based on the SOI, it is only on the verge of developing into one (but may not worsten).  In either event, we should expect warming temperature until at least December, and possibly March - even if the SOI immediately starts rising. 

       Moderator Response:

       [Rob P] - See Hong et al (2014). They define it as exceeding two standard deviations in the Nino3 index. IIRC Mojib Latif and others published a recent paper on super El Nino and used a different standard altogether.

       And recent published literature, based on climate modelling, does project an increase in the magnitude of ENSO events because of the warming of the ocean. That might be worth a blog post or two explaining why this is so.  

27450. jyyh at 16:58 PM on 28 September 2015
       Climate change set to fuel more "monster" El Niños, scientists warn
       

       I'm still of the opinion this is not a huge El Nino but more like 1982 one. Background has gone up so anomalies look huge, ok. Not too sure we'll see much of the argument about 2016, though. Maybe they'll divert to the pollution argument about coral bleaching. 

       Moderator Response:

       [Rob P] - 1982/83 was a super El Nino, along with 1972/73 and 1997/98. As for coral bleaching, sea surface temperatures along the eastern Australian coast seem to be building already, which may signal trouble ahead for the Great Barrier Reef.    

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