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“Global warming has paused”—NOT!

by Donald Prothero, Apr 22 2014
Any data set can be falsely manipulated to distort its meaning. For example, if you just plot short segments of the noisy climate data set, you could imagine a series of short-term "cooling" trends. But statistically the only valid approach is to average over the long term, when there is undeniable warming taking place

Any data set can be falsely manipulated to distort its meaning. For example, if you just plot short segments of the noisy climate data set, you could imagine a series of short-term “cooling” trends (click on the image). But statistically the only valid approach is to average over the long term, when there is undeniable warming taking place

In the spirit of Earth Day, which happens today, I’ll blog about another important ecological topic: the alleged “global warming pause”.

About a year ago, I wrote a post about the climate-denier myth that “it’s been cooling since 1998″. As the post pointed out, this is based on cherry-picking the anomalously warm year of 1998 (atypical because it was an extraordinary El Niño year that brought a lot of heat from the tropical oceans into the atmosphere), then deliberately picking one or two years following and calling that “cooling”.

As the climate deniers have been called out about this lie, they’ve shifted the goalposts, and made the claim that the global warming has “paused” since 1998. As reported in Mother Jones, Fox News began playing this meme over and over again in 2012, so that soon the regular media were echoing their meme as well. But is it true? NO!

1) If you look at the record over the short-term (1998-2012), that’s a very short window to evaluate climate change, biasing your result by cherry-picking 1998 as the starting year. If you shift the frame just 5 years earlier (1993-2012), you’d get a warming trend instead, so such short-term averages are meaningless when they can be distorted by your choice of starting and ending points. In any case, climate scientists would point out that we can’t use the trend over 5 years or even 10 years to make any worthwhile conclusions. The main reason that we cannot look at records on the short term of 5-10 years or less is that there is too much “noise” in the data from short-term events, like the El Niño-La Niña cycles and other events that have nothing to do with the underlying causes of long-term climate change. The only valid approach to the data is to average over very long terms (20 to 30 years at the minimum). As you can see by clicking on the graphic, the long-term trend is unmistakable, and it’s scientifically invalid to cherry-pick a few short-term “cooling trends” of less than a decade in such a long-term record.

Once the missing data from Arctic temperatures (red) are added to the global average, the warming trend is much more striking and the "pause" disappears

Once the missing data from Arctic temperatures (red) are added to the global average, the warming trend is much more striking and the “pause” disappears

2) It turns out that this “pause” in the data set is not real—it’s due to missing data and incomplete data collection. For years, the global temperature average was calculated for about 84% of the earth’s surface, but did not have any of the Arctic temperature data because of the shortage of weather stations up there. But two different studies were just published which used the satellite temperature data from the Arctic to revise the global temperature average. Scientists have long known that the Arctic is warming and melting much faster than the rest of the world, since it is much more sensitive to climate change, and thus more likely to affect the average than other regions that are less sensitive.  Sure enough, the “pause” disappears, and each year since 2003 shows much warmer global average temperatures than the old, incomplete data sets. When you fit a long-term regression to the more complete data, the upward trend is truly striking, with no “pause” whatsoever.

3. There may be another factor at work as well. The atmosphere is only a tiny part of the world’s complex system of water and gases that make up the hydrosphere and atmosphere. We’ve long known that most of the excess heat we’ve produced has gone into the largest sinks, the oceans, which have also warmed significantly over this time period as well (even though the high heat capacity of water makes the trend a lot slower). As a recent study by Trenberth and Fasullo (2012) just showed, since 1998 the Pacific Ocean has been warming much faster than in the past; another study has just confirmed it. This suggests that the  capacity of the oceans to absorb all that carbon dioxide and heat energy has been exceeded, and now the oceans are taking up the heat faster than the atmosphere does. If this in indeed true, the new estimates that incorporate the missing Arctic data are not warming fast enough. If one includes the oceans and atmosphere together, the planet is warming much faster than anyone imagined!

The atmosphere is only a tiny portion of the ocean-atmospheric system. The oceans are vastly more important, and new data shows they are warming at an alarming rate as they have exceeded their heat capacity. The "skeptics" (read "deniers") are only looking at the tiny portion represented by the atmosphere

The atmosphere is only a tiny portion of the ocean-atmospheric system. The oceans are vastly more important, and new data shows they are warming at an alarming rate as they have exceeded their heat capacity. The “skeptics” (read “deniers”) are only looking at the tiny portion represented by the atmosphere

Naturally, this complex scientific explanation goes right over the heads of most of the media, who can only understand and report on simplistic stories with a easy-to-remember punch line. Thus, we  have plenty of people out there—not just the climate deniers and their backers in the right-wing think tanks and energy companies—who’ve been suckered in by this lie, and still haven’t learned what’s really going on.

Recommended Reading

59 Responses to ““Global warming has paused”—NOT!”

  1. Deen says:

    As the climate deniers have been called out about this lie, they’ve shifted the goalposts, and made the claim that the global warming has “paused” since 1998.

    I didn’t get the impression that they shifted because of criticism (since when do they listen to criticism?), but simply because even with the cherry-picking, they can no longer get a clear cooling trend between 1998 and now. Thanks in part to the warm years of 2005 and 2010, which in many data sets are warmer than 1998 (for example, see the annual analysis of the NCDC), claiming a “pause” is now the best their cherry-picking can get them.

  2. Greg Laden says:

    And it seems almost certain at this point that we’ll be having an El Niño year of one sort or another this year, which may provide an opportunity for a lot of that heat hiding in the ocean to move into the atmosphere.

  3. Glenn Storrs says:

    This is absolutely spot on. Just as the scientifically illiterate do not distinguish between climate and weather, they typically do not take long-term (nor broad-based) views on available data. Short-term U.S. temperature trends (or limited data points) may have little to no relationship to global temperatures, for example. Worse yet, the lack of interest in examining available data for themselves, rather than being led by misrepresentations fed to them by vested interests is maddening! As a geoscientist with public outreach responsibilities, I run into the “cooling/pause” myth all the time. Fortunately, I am in a position to correct this misunderstanding when I hear it.

    • tmac57 says:

      Worse than that Glenn.I still see folks that seem to think that they have a killer argument against AGW in the form of “Al Gore!…Climategate!…Hockey Stick!” Sigh.
      It’s like debating evolution with someone who starts out with “Why are there still monkeys?” and think that they have really “gotcha”.

  4. Mark Scurry says:

    A serious question for the experts here.

    What will it take for the broader populace to accept the scientific reality, and then for their elected officials to genuinely act in their best interests? Is it going to take a major city being obliterated by a catastrophic event or something similar? There seems to be an unbridgeable gulf between absolute consensus on one side (scientists), and almost joyous ignorance on the other (deniers).

    • I’m afraid you might be right, Mark. All the talking by scientists didn’t move the needle much, but the polls in 2012 right after Hurricane Sandy suddenly pushed the public to about 70-80% acceptance of climate change. Even though an individual weather event is not the same a climate, it’s extreme weather events that change public attitude, not PR or scientific announcements.
      However, the U.S. is the ONLY major developed country (other than Australia right now, but not before the last election) that has climate deniers in positions of power causing political paralysis. I”m hoping that given the demographics, the climate deniers will be out of power in a few more election cycles, especially as they advocate other anti-women, anti-minority policies which drive out the majority of American voters.

      • Nyar says:

        I wouldn’t put too much hope into that Donald. Remember when democrats held the Presidency, the House of Representatives, and a filibuster-proof majority in the Senate? Did they take that opportunity to save the planet? Naw, that could wait, they passed Obamacare instead. LOL

    • tmac57 says:

      From what I can tell,most Americans are not really engaged in the problem at all,whether accepting or denying AGW. That is to say,that even if they have an opinion,they know next to nothing about the science that underlies what climate scientists are researching.
      I have been reading about this on almost a daily basis for 7 years now,and I would not ever assert that I have any expertise on the subject,yet my knowledge about it is probably 10 time what the average person on the street might have.And yet they often have VERY strong opinions about it despite not really having even a beginner’s understanding of the issues.
      The upshot of that,is that even if they accept AGW,they really have no feel for the urgency,and it kind of becomes like a tragedy that occurs half way around the world that kills thousands…they know it’s real and serious,but they are otherwise disengaged and preoccupied with their immediate lives instead of actively engaged.

    • Nyar says:

      I am not an expert but I have a suggestion for you.

      You might to offer them something. Many skeptics believe that this is all just an attempt to saddle us with more taxes. If you were willing to compromise, say abolish the income tax for all Americans and replace it a carbon tax, enough of them might come on board. Surely it would be worth getting rid of income taxes to save the planet right?

      • Mal Adapted says:

        Nyar: the argumentum ad consequentiam against the scientific consensus on AGW is merely fallacious (or conspiracist ideation if you think that the global community of climate scientists since Tyndall have been engaged in a conspiracy to raise your taxes). Your concerns are appropriate, however, when it comes to deciding what should be done about AGW.

        Opinion among economists and policy analysts is converging on the imposition of a carbon tax, both to internalize the socialized (i.e. environmental) costs of fossil-fuel burning and to help make alternative energy sources more price-competitive. A carbon tax can be revenue-neutral, for example by rolling back income taxes, and still have the desired effect. If a tax based on the carbon content of fossil fuels is paired with a Border Tax Adjustment (BTA), that is, a tariff on imported goods based on the estimated amount of carbon emitted to produce them, U.S. domestic manufacturers would not be disadvantaged. A BTA would have to be adjudicated by the World Trade Organization, but opinions from international law experts are that it would be legal.

        Just how high a tax should be imposed, how to make it revenue-neutral etc. are in the diabolical details.

  5. BillG says:

    Ignore the deniers – lets start the REAL debate. What are we going to do about it?

    There’s plenty on all sides who dwell in fantasy.

  6. lehilgs says:

    It is a sad affair when all who live on this giant ball we call home, cannot wrap their heads around what we are causing. We need someone to have a hard look at the effects we are having and WE need to act accordingly. before it is simply too late. This one is NOT a joke. This folks is very real. If you do not agree well, go have kids and let them die because of your stubborn hardness. We were not born with gills. we cannot withstand a nuclear winter. We ARE indeed seeing the effects in our short lives. What about our children and our children’s children’s children? We will not survive as a species if we cannot get this under control. WAKE UP WORLD!!!

  7. Taylor Pohlman says:

    Very interesting post – I like the animated graph with the segments. However, I think it’s vulnerable to attack without sourcing of the data set used, since skeptics typically use GSS or UAH or similar datasets for their assertions. For that matter, the graph is also vulnerable to criticism given that the data seems to stop around 2010, when three more years of data are available. That would tend to make the last segment a bit longer, but to avoid the appearance of “cherry picking”, it’s probably worth updating it.

    Also, another area what wasn’t clear was the mention of adding additional Arctic data from satellite records to the regular data set (Met Office in this case). Given that statement, it would be helpful to mention that the regular data set includes Antarctic data (I assume it does), since Arctic and Antarctic temperatures have been trending differently.

    Finally, it would be helpful to potentially use the same data sets in the two different graphs, since the trends in the temperature anomalies look to be significantly different in the two graphs (+.4 C in the Met Data graph vs. about .6 C over roughly the same period in the first graph).

    Just some observations to hopefully improve an important argument, thanks,
    Taylor

  8. Peter Ozzie Jones says:

    Dear Don
    first, thanks for continuing to fight so many battles on the side of reason.

    Down here in Australia we had a tax on carbon emissions, might be changed to a so-called “Direct Action Play” with the change of government from the previous Labor one.

    On out ABC Lateline programme, an interview with Maurice Newman, the chairman of the Prime Minister’s Business Advisory Council.

    As in the Bible, he thrice denies that the 97% of climate scientists agree about AGW were valid:

    “MAURICE NEWMAN: They all come up with flawed methodologies. So we don’t pay any attention to that. We know that there are a whole host of scientists out there who have a different point of view, who are highly respected, reputable scientists. So the 97 per cent doesn’t mean anything in any event because science is not a consensus issue. Science is whatever the science is and the fact remains there is no empirical evidence to show that man-made CO2, man-made emissions are adding to the temperature on earth. “

    No evidence that man has caused warming
    http://www.abc.net.au/lateline/content/2014/s3990190.htm

    I’d be interested in your comments on this . . .

  9. Jay Bollinger says:

    That the Earth is in a warming trend there is no doubt. It is also true that heating and cooling cycles of our planet are natural occurrences. Please show me the science proving that man is the cause of this warming cycle. As a skeptic, that’s what I want to see and have not…..yet.

    • There are DOZENS of lines of evidence, but the easiest to see is the EPICA-1 core, which spans 680,000 years of Antarctic history, and more than 6 full glacial-interglacial cycles. AT NO TIME during the warmest interglacials did carbon dioxide rise above 280 ppm, or temperature warm that much beyond what we saw 200 years ago. But our current rise past 400 ppm is WAY OFF SCALE for the warmest cycles in the past 680,000 years of natural cycles. THAT cannot be explained by any natural cause, but is clearly human-induced–especially since it began only 200 years ago as the Industrial Revolution took off…

    • Mark Scurry says:

      Jay, if you are a skeptic as you say, listen to those who are trained experts in the fields relevant to the discussion. When 97% of scientists agree on any topic you can be fairly confident it hasn’t been reached quickly nor easily. The evidence isn’t hard to find and it seems pretty overwhelming. And there is more of it all the time pointing in one direction.

      • markx says:

        When 97% of scientists agree on a matter as complex as climate science you can probably assume they are worried about their ongoing careers and ongoing sources of research funding.

      • If you think this is how scientists operate, Markx, you obviously don’t know much about science or science funding. As someone who has had numerous NSF grants, chasing grant funds is NOT a way to get rich–most scientists make very little money, and work horrendous hours, even the success rate in many branches of NSF (such as mine) is barely 15%. You get better money–and better odds–in Vegas. Besides, the vast majority of scientists who get those funds are already tenured, so their jobs are secure whether they get funded or not. If you think scientists are motivated by money only, you have never seen how we work long hours in dangerous places for a miserable salary, all to find out something about the world not previously known. If we were motivated by money, we would be in the oil biz, where the salaries are four to ten times that of academia. Most importantly, if you think scientists can be herded like sheep to conspire to cook up global warming as a device to raise grant funds, you obviously have never seen a real faculty meeting. We’re the most independent, LEAST herded and least motivated by money of any group of people I know!
        Next time don’t even try to talk about something you know NOTHING about.

      • tmac57 says:

        More plausibly,Occam’s Razor might suggest that the other 3% are just mistaken or lying for profit.

      • markx says:

        Yes, sorry, tmac and Donald, I am being a bit cynical there.

        But, I have worked with enough government employed and university based scientists to know how important their funding is to their careers. And how important their careers are to their livelihood and the wellbeing of their families.

        And I’d expect that the chance any sensible average pauper scientist would speak up against this tide of politics, and ‘do-gooding’ (yeah, I just made that one up) is pretty minimal. Yes, they ain’t getting rich, but they are pretty keen to keep eating.

        For the record, I think a lot of areas of science should be widely funded by the government, organisations such as Australia’s CSIRO have made myriad discoveries that may not have eventuated under the auspices of private enterprise. (I also happen to be skeptical of the concept that the market and private enterprise is the answer to everything, but that is another argument.)

        And the climate debate and its politicization are harming organizations like CSIRO, turning opinion and politics against them. Quite a tragedy.

      • Tony Duncan says:

        Markx,
        there certainly is bias in science, and ACC has become an extremely politicized issue. I have absolutely no doubt that many climate scientists have an emotional attachment to ACC, but this is largely because they have been attacked so vehemently.
        The problem is that 1. Donald’s description of the actual situation of being a scientist is a strong counter to that, and 2. the way that bias can manifest itself in distorting science is mostly in granting research that only looks at a limited range of questions and ignores research in areas that might undermine a false consensus. Or similarly creating intense peer pressure that prevents research in areas that are not considered acceptable
        as of yet, I have seen no evidence that climate scientists or funding bodies are refusing to fund or support research into areas that might undermine climate science if the results were not “friendly”. Slso the denier community and fossil fuel industry have more than enough resources money and motivation to fund any area that traditional sources did not.
        The fact that the research being done is almost universally reinforcing ACC theory, and the fact that there is quite vigorous debate about many of the areas of uncertainty (CO2 sensitivity, cloud impacts, biological CO2 sinks and numerous other areas) make it completely obvious that there is no organized attempt anywhere in the scientific community to only fund research that would lead to “supportive” results.
        Also since the research in this area is probably the most scrutinized science ever conducted in history, fraudulent results would immediately be exposed and a storm of protest would ensue.
        the fact that deniers are still obsessed with some mistakes in a paper 16 years ago and contend that is proof of a conspiracy is rather telling.

  10. Marcy Lanning says:

    We all need to stop driving cars, at the very least, and stop using electricity, and stop heating our homes, the carbon pollution is too much for the climate to bear, we all need to get back to mother earth, just the basics, simple farming, living in mud huts, no cutting of trees or even using fire, we must turn back now because it is worse than we thought!

    • Mark Scurry says:

      I suspect there will be a strong amount of realism in the alternatives offered. Very few are going to stop driving cars tomorrow. Very few are going to stop using electricity tomorrow either. An planet of over 7 billion people simply must have resources to even hope to survive. However, if alternatives become readily obtainable and affordable, then hopefully choices will shift. I’ll be installing solar panels to help with electricity, and I’m honestly not bothered by having to spend a fair bit of money for it. The overall benefit is more than worth it.

  11. RoboSapien says:

    Off topic – what happened to all the other authors on this blog? Donald seems to be the only one that posts anymore, with the occasional chime in from Loxton or Novella. I see Brian Dunning is still carrying on with Skeptoid, but not a peep from him here since that scandalous affair last year.

    • I don’t know why Steve has stopped contributing–no one has told me anything. Dunning is too busy with his legal issues to continue, and Loxton and Shermer have always been irregular contributors. Loxton and I are planning on relaunching the site with a new slate of bloggers in the near future…

  12. Frank Wendt says:

    Why did the glaciers melt some 10,000 years ago? Natural cycle?

    • Yes, the natural Milankovitch cycles produce a 10,000-year-long interglacial period every 110,000 years. But our current interglacial (which began 10,000 years ago) never had a carbon dioxide level higher than 280 ppm. Thus, we still had glaciers and ice caps, even in peak interglacial. Since the last century, however, our own carbon dioxide pollution has caused the levels to shoot past 400 ppm. which has NEVER occurred in the past 700,000 years (and six complete glacial-interglacial cycles). THAT is not natural, but human-caused, and THAT is why the planet’s ice caps and glaciers (which date back at least 3.5 million years to the start of the last Arctic glaciation) are disappearing at rates NEVER before seen in geologic history.

      • markx says:

        Dr. Antonino Zichichi, president of the World Federation of Scientists:

        “In the last half billion years, earth has lost, four times, its polar caps: no ice at the North Pole and none at the South Pole. And, four times, the polar caps were reconstituted. Man did not exist then, only the so-called cosmic rays, discovered by mankind in the early twentieth century. The last cosmic ice age started 50 million years ago when we entered into one of the galaxy arms.”

        Source: http://sciencebits.com/files/pictures/climate/crcFig5.jpg

      • This is a classic example of cherry=picking, quote-mining and citing “authorities” with no relevant credentials. First of Zichichi is a nuclear physicist, NOT a climate scientist, so his status as president of the WFS is completely irrelevant. He is no more qualified to evaluate climate science than he is to fix a car or write a symphony, based on those credentials. In fact, Hans Bethe calls him a “mediocre physicist” even! Secondly, he blunders into talking about the geologic past history of climate and gets it completely wrong. Those major long-term greenhouse-icehouse cycles operated on a MUCH slower time scale than the current rapid warming of the earth in just two centuries. Those events took tens of millions of years to go from greenhouse planet to icehouse planet and back again. And in nearly every case, we understand the underlying causes for these slowly changing climate events, and they are completely irrelevant to what is happening to the planet now. Thus, comparing these events to the current man-made global warming is comparing apples to oranges. Finally, it is well documented that there is NO effect by cosmic rays on modern climate–in fact, the cosmic ray flux occurring in the past century predicts global cooling, NOT warming. Neither is the sun’s change in radiation relevant–it too is declining while the planet warms. The ONLY factor that is increasing is the human production of carbon dioxide–the rest is irrelevant smoke screens.
        If you’re going play the game creationists play, Markx, and quote-mine unqualified “experts” citing irrelevant or outdated information, you might as well JOIN the creationists!

      • markx says:

        What makes a climate scientist?

        Physicists, geographers, marine biologists, oceanographers,dendochronologists, geologists, mathematicians, ecologists, economists, not to mention the(very)odd psychologist …. all seem contribute something to this very complex issue…

        But a nuclear physicist cannot?

      • No, a nuclear physicist has no relevant credentials to speak about the primary data base of climate science with authority. The very fact that this particular nuclear physicist made such bonehead mistakes about ancient climates further proves that his opinion about climate change is based on no understanding of the subject whatsoever. For that matter, many of those other people you list (especially economists and psychologists, as well as meteorologists) have no firsthand research experience in climate science, nor any peer-reviewed publications in the field, and they too are not qualified to comment on a field for which they have never received any relevant training.
        I’ve been working on climate change and paleoclimate since the early 1980s, specializing in the largest climatic change of the past 50 million years, the Eocene-Oligocene transition (you can look it up and see I’ve written and edited numerous books on the topic, most recently “Greenhouse of the Dinosaurs”. I also worked on deep-sea cores and microfossils (and published on them), and worked closely with climate modelers, ice-core specialists, tree-ring experts, and a variety of other people who DO have first-hand familiarity with the primary data of climate change. That is the only kind of expertise and training relevant to the topic.

      • markx says:

        Donald says: ‘…join the creationists…”

        I think we agree on most things, Donald, barring the degree of certainty of climate science. We certainly hold similar views on the creationists.

        But bringing religion in perhaps does seem appropriate somehow in the context of the way this debate is handled.

        ….”Believe. Do not question anything. The truth is already known. He who asks will be scorned, and labelled and ridiculed, for some things simply are, and must not be questioned.”

      • Mal Adapted says:

        markx: can you explain why you think climate scientists are less trustworthy than evolutionary biologists?

      • markx says:

        Hi Mal.

        Can you please define ‘climate scientist’?

  13. Andyj says:

    First post! Hello all. :)

    Those temperature graphs do not associate closely with any existing dataset. Maybe I was looking at the graph all slanted. Later on there is a reference to Hadley. Is it HADCRUT4? Being the main set that warms the future and cools the past over HADCRUT3.
    So here is HADCRUT4 with 12 month smoothing.
    http://www.woodfortrees.org/plot/hadcrut4gl/from:1980/mean:12/plot/hadcrut4gl/from:2000.8/trend

    I have a problem here. Apart from one young man being a cartoonist with an AGW blog (SkS). There is over 13 years of totally no global warming using this empirical data!

    Perhaps I ought to take the average basket of *all* temperature datasets and include CO2 as well – suitably 12 month smoothed to remove seasonal noise. Then de-trend CO2 and magnify variances (bumps). With that I can compare it with temperatures to see if CO2 is a warming gas at these concentrations. (MODTRAN calculates to 0.236C per doubling of CO2 which seems low).
    http://www.woodfortrees.org/plot/wti/from:1997/offset:-0.5/mean:12/plot/esrl-co2/from:1997/normalise/mean:12/detrend:0.81/offset:0.42/scale:10/plot/esrl-co2/from:1997/normalise/mean:12/plot/wti/from:2000.85/offset:-0.5/trend/plot/esrl-co2/from:1997/normalise/mean:12/detrend:0.81/offset:0.42/scale:1

    Oh, the proverbial has hit the fan with empirical data. CO2 lags behind the climate variation. No GW for 13.5 year’s while CO2 is sky rocketing like a monkey with its bum on fire during the longest interglacial for quite a few cycles. Is it because our God loves us?

    Obviously the Ocean store is losing CO2 from warming up because man’s contribution is but 3~5% of the tonnage. But it’s very odd when the ocean sea ice content appears stable.
    http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/global.daily.ice.area.withtrend.jpg

    Maybe de-gassed water freezes more readily?

    If this does not get published. I will learn more of the AGW movement in one stroke than reading what others say.

    • DId you even READ the post? You CAN’T generalize about the trend of climate for the past 13 years, because that is too short a time span to filter out the noise. This is ESPECIALLY true if you cherry-pick the data and start in the anomalously warm El Nino year of 1998, which is statistical noise and irrelevant to the long-term trend. Besides there are LOTS of years (2009, 2010, and 2013 already) which were WAY warmer on a global basis than 1998–and as I explained in the post, the warming trend is even more obvious when we add in the long-missing data from the Arctic, where the warming is occurring fastest.
      Next time, try to READ THE POST before you cite outdated and irrelevant information to criticize it.

    • markx says:

      Thirteen years is likely too little to make statements or claim of observed trends, but is 20 or 30 years likely to be enough?

      • Tony Duncan says:

        Markx,

        Yes, that is because CO2 and temperature are not connected in a linear fashion. Climate and global temps are subject to a wide range of factors that are part of natural variation. the effect of CO2 will NEVER be so strong that it will obliterate those other factors. No matter what the global temp is in any decade it is likely that temps will increase, decrease or “pause during some part of that period.
        we know that solar insolation decreased this decade format eh extremely low solar activity cycle, and almost surely form Asian pollution as well. We know ( although it is still tentative) that ocean temps have increased rather dramatically this decade as well, and that we have been in a a Nina dominant ENSO. those are all factorss not generally included in climate models that should have led to significantly decreasing temps.
        But I will happily acknowledge that is temps continue to stay at this plateau or decrease over the next 10 years that there is some serious problem with ACC theory.

  14. markx says:

    It is all not quite as simple as Donald would like to imply.

    A good read of Judith Curry’s blog is always worthwhile, and especially her recent post on Richard Tol and Robert Stavins pointing out how faulty the IPCC processes are (especially the politics)

    http://judithcurry.com/2014/04/26/stavins-and-tol-on-ipcc-wg3/

    Tol: The SPM omits that better cultivars and improved irrigation increase crop yields. It shows the impact of sea level rise on the most vulnerable country, but does not mention the average. It emphasize the impacts of increased heat stress but downplays reduced cold stress. It warns about poverty traps, violent conflict and mass migration without much support in the literature. The media, of course, exaggerated further.

    …[...]… and …[...]…

    In the earlier drafts of the SPM, there was a key message that was new, snappy and relevant: Many of the more worrying impacts of climate change really are symptoms of mismanagement and underdevelopment.

    This message does not support the political agenda for greenhouse gas emission reduction. Later drafts put more and more emphasis on the reasons for concern about climate change, a concept I had helped to develop for AR3. Raising the alarm about climate change has been tried before, many times in fact, but it has not had an appreciable effect on greenhouse gas emissions.

    • Anyone who cites a notorious climate denier without the relevant credentials like Judith Curry does not deserve a detailed rebuttal to this pile of drivel.

      • markx says:

        Except it is not about Judith Curry, is it?

        It is about the thoughts and opinions of two well known IPCC authors/researchers.

        …but, re J Curry:

        She is chair of the earth sciences department at Georgia Tech and has written a textbook on ocean and atmosphere physics.

        Her main aim seems to be to want scientists to be honest about the uncertainties of this particular branch of science.

      • Canman says:

        How is Judith Curry a ‘notorious climate denier’?

      • markx says:

        From Wikipedia:

        Professor Judith A. Curry is an American climatologist and is chair of the School of Earth and Atmospheric Sciences at the Georgia Institute of Technology.

        Her research interests include hurricanes, remote sensing, atmospheric modeling, polar climates, air-sea interactions, and the use of unmanned aerial vehicles for atmospheric research. She is a member of the National Research Council’s Climate Research Committee.

        Curry is the co-author of Thermodynamics of Atmospheres and Oceans (1999), and co-editor of Encyclopedia of Atmospheric Sciences (2002), as well as over 140 scientific papers. Among her awards is the Henry G. Houghton Research Award from the American Meteorological Society in 1992.
        http://en.wikipedia.org/wiki/Judith_Curry

      • From the Skeptical Science, the primary website of climate scientists: http://www.skepticalscience.com/skeptic_Judith_Curry.htm
        And from Scientific American, http://www.scientificamerican.com/article/climate-heretic/

        She’s a climate denier, and very much outside the mainstream scientific community in her contrarian views.

      • markx says:

        Donald Prothero says: April 29, 2014 at 11:07 pm

        From the Skeptical Science, the primary website of climate scientists: http://www.skepticalscience.com/skeptic_Judith_Curry.htm
        And from Scientific American, http://www.scientificamerican.com/article/climate-heretic/

        The SKS site says very little, and Curry’s comments quoted there are worth reading, and it is worth following the links; she comes over as very sensible.

        The Scientific American article is only partly available, but the comments are an interesting need. Note that the first comment is from Judith Curry.

  15. markx says:

    A nice chart of global temperature and CO2, to put things in some perspective:

    http://www.paulmacrae.com/wp-content/uploads/2008/06/co2-levels-over-time1.jpg

    • Papy says:

      And two nice articles pointing to markx’s blatant lack of genuine skepticism, as usual :

      http://tinyurl.com/o5e3bx9
      http://tinyurl.com/osj6ok9

      • markx says:

        Thanks Papys, interesting pages. I am not sure they assuage my doubts (which are more about the clarity of knowledge and the pace and urgency of the demands for response, rather than whether or not man contributes somewhat to warming).

        But look, a skeptic is a skeptic is a skeptic.

        I could be skeptical of the fact the sky is blue. You would say I’m wrong, but if I still disagreed you could go away and accurately state to someone else “He is skeptical of this fact”.

        It is just a word, not a religion, or a way of life, or a badge of honour. There are no ‘fake skeptics’ only skeptics, (and, by definition, perhaps unreasonable!);

        skep·tic ˈskeptik/ noun
        noun: sceptic; plural noun: sceptics; noun: skeptic; plural noun: skeptics

        1.a person inclined to question or doubt all accepted opinions.
        synonyms: cynic, doubter; pessimist, prophet of doom
        “skeptics said the marriage wouldn’t last”
        a person who doubts the truth of Christianity and other religions; an atheist or agnostic.
        synonyms: agnostic, atheist, unbeliever,onbeliever, disbeliever,

        2. Philosophy … an ancient or modern philosopher who denies the possibility of knowledge, or even rational belief, in some sphere.

  16. iamihop says:

    I wish people would stop trying to sweep the last 15 years under the rug. It’s tempting to do so, because deniers will latch onto it as evidence that warming isn’t happening. However, the climate research literature has recognized that the surface and atmospheric warming has stalled dramatically, and we’re not sure why. I think it’s fascinating, and if we can figure out exactly what is contributing to it, then we’ll understand the system that much better.

    It doesn’t take much playing with this awesome tool to see the change over the last two decades: http://www.skepticalscience.com/trend.php

    For example: “An apparent hiatus in global warming?” 2013
    http://onlinelibrary.wiley.com.ezaccess.libraries.psu.edu/doi/10.1002/2013EF000165/full

    “Atmospheric science: Increasing wind sinks heat” 2014
    http://www.nature.com/nclimate/journal/v4/n3/full/nclimate2138.html

    or

    “Recent global-warming hiatus tied to equatorial Pacific surface cooling” 2014
    http://www.nature.com/nature/journal/v501/n7467/abs/nature12534.html

    • Mark Scurry says:

      I just wish people would listen to the actual climate scientists.

    • markx says:

      Funny thing is, iamihop, I take the opposite view to you on this one. I feel far too much is made of the so called hiatus by the … um…. ‘those who would question the state accuracy and extent of knowledge on the subject of anthropogenic climate change’. (I’d better not call them CAGW skeptics, it looks like the word has been rebranded).

      Donald is almost certainly correct in saying that 13.5 years is too short a time period to make pronouncements on … but I’d think, so is 30 or 50 years.

      • Mal Adapted says:

        Markx, if you want to understand the statistical rationale for needing 30 years to detect a trend, try here:

        http://moregrumbinescience.blogspot.com/2009/01/results-on-deciding-trends.html

        The blogger, Robert Grumbine, says he’s “writing to be inclusive of students in middle school and jr. high*, as well as teachers and parents (whether for their own information or to help their children).” I presume most of us are up to it 8^D!

        For a more detailed explanation of statistical methods in climatology, try the WMO’s Guide to Climatological Practices:

        http://www.wmo.int/pages/prog/wcp/documents/Guidefulltext.pdf

      • markx says:

        Thanks Mal.

        I understand the statistical basis for such a conclusion.

        But a confounding issue for me is the largely unexplained longer term changes to earth’s climate, even in recent times – eg – the approx 300 year Little Ice Age.

  17. Oldskool says:

    I am absolutely blown away that people who purport to be skeptics (or even sceptics) can demonstrate such patently unskeptical thought as to deny climate change. Carbon Dioxide is a greenhouse gas, period, of that there is no doubt- we are pumping more of the stuff into the atmosphere than in pretty much any time in history (real history not just recorded history). This has a specific effect, it creates warming, there is no denying this. The sun is currently at a minimum, yet last year was the hottest on record the ENSO has been kind and we have a la nina followed by 2 neutral years, but it is turning and we are heading towards an el nino, you think that 2013 was hot, wait until that puppy hits!

    All you deniers there can keep cherry picking and finding your favourite energy company sponsored scientist to quote but that doesn’t change the data, or even for that matter the simple chemistry/ physics of the situation.

    I find it amazing how so many of you faux skeptics are so good at pulling anomolous data whenever you need support just like bigfoot hunters or homeopaths. You are not a skeptic, you are not looking at things critically, you are letting your political ideaology lead you, you are, as Donald said, no better than creationists.

  18. Mark Scurry says:

    Well said Oldskool, you expressed the sentiments some of us feel very well.

  19. Andras Szilagyi says:

    I don’t understand this sentence: “This suggests that the capacity of the oceans to absorb all that carbon dioxide and heat energy has been exceeded, and now the oceans are taking up the heat faster than the atmosphere does.”

    Did you mean the capacity of the atmosphere, rather than the oceans?
    Also, I don’t see how the capacity to absorb carbon dioxide comes in.

  20. Jerrold Alpern says:

    The Royal Society in the UK and the National Academy of Sciences in the US are the two most authoritative and prestigious science organizations on the planet. They have recently jointly published a paper, “Climate Change: Evidence and Causes”. https://royalsociety.org/~/media/Royal_Society_Content/policy/projects/climate-evidence-causes/climate-change-evidence-causes.pdf

    In clear, concise, easy to understand language, it lays out the evidence for AGW. No one can reject the arguments contained therein, without also rejecting the ordinary norms of logic and discourse that they accept elsewhere in daily life as well as basic chemistry, physics and biology (among other disciplines).

    • markx says:

      Thanks Jerry.

      It is a nice summary. And I have read almost every word and seen every graph elsewhere.

      I disagree that acceptance or rejection of the arguments therein require similar acceptance or rejection of basic chemistry, physics and biology.

      What you have there is a logical explanation, supported by computer models.

      I don’t reject the explanation.

      However, I also don’t simply accept it as I can see many potentially confounding issues, and few proofs.