Climate Change Uncertainty For Next Few Decades


Man-made or natural?

Earlier this month, there was a bit of reporting on a draft of a new study, Special Report on Managing the Risks of Extreme Events and Disasters to Advance Climate Change Adaptation (SREX), by Intergovernmental Panel on Climate Change (IPCC) dealing with future trends in extreme weather. After seeing a leaked version of the SREX's Summary for Policymakers, the AFP reported

A new UN report concludes that man-made climate change has boosted the frequency or intensity of heat waves, wildfires, floods and cyclones and that such disasters are likely to multiply in the future…

– It is "virtually certain"—99-100% sure—that the frequency and magnitude of record-hot days will increase over the 21st century on a global scale.

– It is "very likely" (90-100% certainty) that the length, frequency and/or intensity of warm spells, including heat waves, will continue to increase over most land areas.

– Peak temperatures are "likely" (66-100% certainty) to increase—compared to the late 20th century—up to 3.0 degrees Celsius (5.4 degrees Fahrenheit) by 2050, and 5.0 C (9.0 F) by 2100.

– Heavy rain and snowfall is likely to increase, especially in the tropics and at high latitudes.

– At the same time, droughts will likely intensify in the Mediterranean region, central Europe, North America, northeastern Brazil and southern Africa.

– Rising and warming seas are also very likely to boost the destructive power of cyclones, while melting glaciers and permafrost, along with heavier precipitation, will trigger more landslides.

Now, BBC reporter Richard Black has apparently seen a more recent draft version that acknowledges a lot of scientific uncertainty about such predictions. He reports:  

The draft, which has found its way into my possession, contains a lot more unknowns than knowns.

On the one hand, it says it is "very likely" that the incidence of cold days and nights has gone down and the incidence of warm days and nights has risen globally.

And the human and financial toll of extreme weather events has risen.

Human hand fingered?

But when you get down to specifics, the academic consensus is far less certain.

There is "low confidence" that tropical cyclones have become more frequent, "limited-to-medium evidence available" to assess whether climatic factors have changed the frequency of floods, and "low confidence" on a global scale even on whether the frequency has risen or fallen.

In terms of attribution of trends to rising greenhouse gas concentrations, the uncertainties continue.

While it is "likely" that anthropogenic influences are behind the changes in cold days and warm days, there is only "medium confidence" that they are behind changes in extreme rainfall events, and "low confidence" in attributing any changes in tropical cyclone activity to greenhouse gas emissions or anything else humanity has done.

(These terms have specific meanings in IPCC-speak, with "very likely" meaning 90-100% and "likely" 66-100%, for example.)

And for the future, the draft gives even less succour to those seeking here a new mandate for urgent action on greenhouse gas emissions, declaring: "Uncertainty in the sign of projected changes in climate extremes over the coming two to three decades is relatively large because climate change signals are expected to be relatively small compared to natural climate variability".

It's also explicit in laying out that the rise in impacts we've seen from extreme weather events cannot be laid at the door of greenhouse gas emissions: "Increasing exposure of people and economic assets is the major cause of the long-term changes in economic disaster losses (high confidence).

"Long-term trends in normalized economic disaster losses cannot be reliably attributed to natural or anthropogenic climate change."

The new report is scheduled for release this Friday, so it will be interesting to see if the IPCC highlights or downplays the scientific uncertainties. 

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  1. Why the fuck is anyone still talking about this discredited, idiotic bullshit?

    1. I hear ya. Bailey seems to have found his fetish.

      1. You do know that it’s his job to cover the science beat, don’t you?

  2. is possible only in the presence of the agricultural city-STATE, which after all did make the horrible pollution producer called the Industrial REVOLution possible. Of course, faux “liberty” lovers will use the police power of the state to defend their precious enTITLEments.
    Officer, am I free to gambol?

    1. Here we go. [plays a steady rhythmic riff] Hey, this guy’s good. [sings] “Well, I’m gambolin’, gambolin’ ’round, I’m a gambolin’ guy, I’m gambolin’, oh, yes, oh, yes!” [whistles poorly, shrugs, speaks] Free to get in. [sings] “I’m a gambolin’ guy – G-A-M-B-O-L-I-N apostrophe, oh yes, I’m gambolin’ — Ga day. Oh, yes.” [speaks] Okay, everybody! “I’m a gam–” Come on! Sing with me! Come on, have some fun, come on! “Gambolin’ …” Are you people uptight or somethin’? You can’t sing along–? Oh, I forgot… New York. [applause, keeps playing] Okay! All right, ladies only! “Oh, look! A gambolin’ guy!” Come on! Okay, this half of the room! Beautiful! Now this half! Good, good! All right, two fifths! Now, three-fifths! Good. Seven-ninths! Two-ninths. All right, in Chinese now! [sings Chinese gibberish, then sings in English:] “Well, I’m gambolin’, gambolin’, gambolin’, gambolin’, gambolin’, gambolin’, gambolin’, gambolin’! Gam! Boh! LINNNN!” [suddenly launches into a long, snappy, complex banjo instrumental, smiles and raises eyebrows at audience, stops, takes a fake arrow-through-the-head prop from the stool and puts it on] I like to keep the laughs rolling even while I’m playing. [finishes banjo tune triumphantly] Heyyyy….I’m Rectal the Klown…and I’m here all the [TIME]!


  3. And yet I can still at night.

    1. Still sleep. Fckin smartphones.

  4. How many major hurricanes hit our mainland this year? Good luck convincing Americans that we should worry about extreme weather events due to global warming.

  5. It is virtually certain (99%-100%) that the IPCC is driven by political motivations.

    1. What motivations would those be?

        1. Is it that among all the sciences, climate scientists are easily corruptible? Or do you find a massive conspiracy of every scientific body on earth to invent a crisis out of thin air in order to secure somebody power and money to be plausible? You’d think, since they were inventing the crisis, they’d pick one that didn’t directly challenge the profits of the most powerful industries on earth. But then, even those industries now freely admit climate change is real. So I suppose Exxon is now part of the global conspiracy?

          1. Addressing your comments from back to front, uhm, yes Exxon is part of the global conspiracy to fight Climate Change science, or so I’m told.

            Also, I didn’t suggest they– climate scientists– were “inventing a crisis”, I’m suggesting that they have an interest in perpetuating the idea that a particular problem or highly debatable issue is a crisis.

            Most scientists aren’t in fields which have a massive, globally affecting policy outcome. So yes, I would argue that climate scientists are, at this moment in time, at the forefront of corruptability.

            Climate Change is an absolute cash cow of grants and government-funded research. To suggest that a central group of scientists (IPCC) are completely immune to any form of corruption is naive.

            It’s not a conspiracy as some people suggest. It’s simply an environment which fosters an interest to make dire predictions and garner media attention.

            1. But aren’t there interests on the other side as well? Exxon doesn’t advertise its awareness of climate change because it wants to take a hit on profits, but because it is no longer possible to deny climate change and be considered a serious person. That it persists here among people who tend to appreciate science is unfathomable to me. The fact is almost all published work denying climate change was in some way funded by fossil fuel industries. That is a very direct and understandable interest.

              The goal of the conspiracy you’re positing is vague and totally unbelievable–there are much simpler ways to make a buck than to get a doctorate, get published, then collude with other experts to invent a crisis to secure government funding. If you want to make that claim then you cannot ignore the interests in climate change denial, that would be the height of intellectual dishonesty. And once you weigh those against each other, even with the clearer motive on the denier side, still virtually all climate experts have reached the same conclusion.

              Climate change denierism is simply not a serious position given the evidence. It is absurd to suggest that 99% of climate science experts are all people with a vested interest in a particular policy. It’s crystal clear that people with an ideological problem with government action have the greater tendency toward bias in this matter.

              1. The goal of the conspiracy you’re positing is vague and totally unbelievable

                Who cares about the conspiracy the FUBAR which is the “evidence” for man made global warming is well documented as being a complete and utter fucking mess.

                It can’t even be described as science in any sense of the word.

                You don’t have to be conspiratorially minded to make that observation.

              2. I want to see the global list along with a little detail on what is considered “expert”. You don’t have this list though do you. In fact, you are simply repeating something you’ve read elsewhere, with no verification that it is even remotely true.

            2. Plus you’re suggesting that any science with global policy implications is inherently biased (though I don’t know where you get the idea that all scientists are globalists).

              There is no greater bias-eradicating tool than science. That’s its job. If one field is corrupted to the core, which I suppose is possible, you have to prove it, and that hasn’t been done yet. The fact is if you haven’t accepted the science yet you never will, and that makes you the biased party.

            3. Correction: IPCC is not a group of scientists.

          2. climate scientists

            First off Micheal Mann is one person not a plurality of scientists.

            Second he isn’t even really a scientist more like a “What If” comic book writer for statistics.

            You know like what if the medieval warming period actually didn’t happen, Or what if i turn proxy data and upside down, or used a “trick” with tree rings that show cooling in the modern era by cutting them out.

  6. Let’s just keep doing what we’re doing and see what happens.


    1. What’s

      You could continue to post.

  7. 66% of the time, it works every time.

    1. With a standard 6-shot revolver used for Russian roulette, there’s only a ~17% chance of a single round firing with a single trigger pull. That is, there’s a >83% chance of not dying.

      And yet, we think that anyone who plays Russian roulette is a crazy, reckless fool.

      Why would we blow the head off our economy, and the life expectancy, standard of living, etc., on a much lower chance that something “bad”, but not devastating, might happen?

  8. Anyone else notice that when the forecast is for warm weather the guy says “temperatures will be warmer than normal”, and when the forecast is for cold weather the guy says “temperatures will be colder than average”?

    Never “warmer than average” and never “colder than normal”.

    1. Seems like the old joke about the Soviet news media reporting on a two-person race: “The Russian came in second, while the American was next-to-last.”

    2. That might just be your weather guy. I’m pretty sure I hear “warmer than average” pretty regularly.

  9. Re. alt text: that hideous graphic design is a worse man-made disaster than anything the IPCC can prove.

  10. The only people who gave a sh*& about GW in the first place were mindless Democrats who 1) wanted to feel smart and science-y and 2) who at cocktail parties needed to steer the question away from why the Iraq was wrong under Bush but oh-so-dreamily right under Clinton.

    The End.

    1. You forgot about Enron who saw a way to cash in on the “problem”, before
      Enron came crashing down.

  11. Damned Keynsian statistics. What does 90% certain mean? Out of 10 earths, one won’t do what you think it will? How about taking these scientists to task and making them put 9-1 odds over one year’s salary for each of these predictions. Comes true, they get a 10% bonus. Comes false, they lose 90% of that year’s pay.

    1. Make them responsible for their predictions? That’s madness! How would they throw out total bullshit then?!?

      1. Why the fuck is anyone still talking about this discredited, idiotic bullshit?

    2. It would never work. If Paul Ehrlich can still claim he was “essentially right” about everything he predicted (millions of people have died since he made his prediction!) you’ll never squeeze out a binary ‘right/wrong’ out of climate science. That’s why “climate change” is such a delicious topic.

      “Hey look! A heat wave! Take that global warming deniers!”

      “Cold snap? Stupid Fox News viewers, weather isn’t climate!”

  12. But the Science, it’s been settled.
    See this book some sciency guys put together.……76&page=R1

    1. What’s the sigil of House Gore?

      1. A hanging chad.

  13. (These terms have specific meanings in IPCC-speak, with “very likely” meaning 90-100% and “likely” 66-100%, for example.)

    Those are not “specific meanings”, since those numbers are still guesses based on models that may or, more likely, may not accurately reflect the real world.

    1. What’s beautiful is that a prediction with 99% chance is essentially saying “100%” for the sake of policy choices, but leaving the predictors an “out” that they can invoke even if they are completely wrong about everything they have ever said.

    2. Also, what is “66-100%”? That is not an accepted way of expressing probability or confidence in any legitimate form of statistical analysis or modeling, and it never has been.

      “66% probability” is what it is. It’s not “66-100%”, any more than “0-66%”.

      1. I think they mean that the people on the panel vary from 66-100% “sure” this will happen.

        1. That would mean that they aren’t throwing out the outliers. “100% sure” should be tossed out.

          No matter how you slice it, it’s not legitimate.

  14. I saw SREX and thought for a second it said SKRILLEX.

    I’ve been monitoring what my daughter has been listening to.

    Much to her horror, I actually kinda like “Scary Monsters and Nice Sprites.”

    But most of his stuff gets pretty monotonous and boring to me after about 38 seconds.

    1. Stupid joke screen name.

  15. It is “virtually certain” — 99-100% sure — that the frequency and magnitude of record-hot days will increase over the 21st century on a global scale.

    I wish there was a good way to bet on this. I’d love to get 98-to-1 on a meaningful translation of this statement. Of course I won’t be alive to collect on it, so I’d have to be able to sell my position later on .. and the unit of account would have to be gold or silver …. etc, etc.

    1. It really shows up the slop (and, therefor, dishonesty) of these statements to try to reduce them to something that would actually be enforceable (read: accountable).

      You can’t do it. Go ahead; try and draft that garbage in the form of a contract that you could verify and take to court.

    2. Hansen of GISS fame made some predictions 20 years ago.

      New york is now according to him underwater.

      The last IPCC report also predicted 0.2 degrees or greater of warming from 2000 to 2010. I think the warming was around 0.07…which considering the margin of error essentially ZERO.

      The man made warming we are to experience is always in the future….the past is irrelevant no matter how much CO2 there was in the atmosphere.

  16. “it will be interesting to see if the IPCC highlights or downplays the scientific uncertainties.”

    Considering that the word “government” is in their name and the word “science” is not, my money is on their downplaying uncertainty rather than highlighting.

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