A paper in Nature this week asks – and tries to answer – a question that nobody, so far as I can tell, in the IPCC's upper leadership has thought would make a good talking point for its big recent report. But it is clever, with proposed answers that are, in principle, easy to understand. That is not the same as saying reporters had an easy time translating the report into simple terms.
To paraphrase the paper – written by specialists at the University of Hawaii – the question is: Region by region, after about what date will the average temperature in every year exceed the hottest years recorded from 1860 through 2004? That is, until the coolest years are all hotter than what used to be the hottest years? Among answers the paper provides is that tropical regions will drift permanently into unprecedented, unrelenting new climates first and Arctic and sub-Arctic areas will fall into the altogether 'new planet' bin last. The paper estimates that the wave of lordy-it's-hot-and-it-never-stops will kick off near the equator in the 2020s and reach the poles by around 2050 and all depending on what greenhouse gas emission scenarios one feeds into the computers.
Enterprising reporters figured out fast that to rev the story up and fast most easily is to name specific cities and their dates with perdition as examples. But the overall picture and the logic behind it are not easy things to describe quickly. Hurdles to its digestibility include the model-dependant fuzziness of the answers – not to mention that contrarians have shouted for so long that computer models are crap that a lot of the public (readership) believes them all to be said crap. Worse is that the paper unavoidably places large statistical uncertainties on its dates, putting plus or minus 14 years or more on them, which only confuses things. Stoutly writing "2047" is so much plainer, if less true, than something like "from 2033 to 2061 with one sigma confidence."
Thus we find stories such as these:
- AFP, as carried by the South China Morning Post: "Extreme climate to affect most of earth with[in] 34 years, new study predicts/ Tipping point will come in 2047..."
- Washington Post – Lenny Bernstein: D. C. climate will shift in 2047, researchers say; tropics will feel unprecedented change first ; Bernstein's copy does imply fuzz around the dates. He puts them, for example, as "If they are correct, the transition will occur by 2020 in Manokwari, Indonesia..2047in Washington DC…2066 in Reykjavik Iceland…" etc. He called a few outside experts. One calls the dates "The boundary of passing from the climate of the past to the climate of the future," not a bad and correctly imprecise way to capture their essential meaning.
Both of those stories talk about a tipping point, but the Nature paper is not about tipping points. That overused term ought to be reserved for things with a feedback that acts like giant book cases that one has to push hard on to get them to lean – until their centers of gravity goes beyond their perimeters and the darned things start pulling instead of pushing back and BAM!. The paper is about a stastistically dramatic division in what is nonetheless a more or less gradual change. Reversing the process does not suddenly get far more difficult at that point, ergo, it's no tipping point.
A perplexing aspect that few news reports tackle is that we all have been reading that global warming will affect the poles earlier and to a greater extent than the tropics. But the tropics will get into all-new territory first, says this report? How does THAT work? It has to do with inter-annual variation. That is, higher latitudes may well get hotter on longer term average fastest and firsted, but the climate up there is far more volatile by nature than it is at the planet's mid-section. Natural cycles leave tropical averages largely alone. Therefore, if the tropical average goes up it doesn't take long for the new baseline (and the envelope of variation around it) to rise above what we've seen since the industrial revolution kicked into high gear. But in Siberia, it will take a longer time before the downward annual spikes in temperature never stab into behaviors we've already seen over the last 150 years. That's about as small as I can digest the explanation and I am not sure how many readers would get that one with a once-through read. The required verbiage might not fit into every news story even if the reporter thinks to try it.
Here's a good one:
- AP – Seth Borenstein: STUDY: Temperatures Go Off The Charts Around 2047 ; The AP graphic implies more precision than the report really has, but text of story has lots of welcome, wobbly terms and phrases such as "probable" and"about a decade" and "a generation or less away".
Borenstein, an exemplar of due diligence on deadline, found time to call at least three outsiders for comment. They are the Smithsonian's Chris Field, Penn State's famously assailed (by contrarian forces) Michael Mann, and another famous and in some circles infamous climate gadfly Judith Curry of Georgia Tech. That last one, Curry, is best known for picking relentlessly on lapses of those who essentially agree with her that climate is changing, while tolerating horrid errors from the contrarian gang and preaching civility and tolerance for them and praising their occasional contributions to serious science. So, one expected her to say something sour about this new report's lack of perfection. But no. Dr. Curry told Borenstein that this new study makes a lot of sense to her, more than does the recent iteration of the IPCC's long running series of climate change science summaries.
There should be more. Curry is a fascinating character whose essential honesty and credentials appear solid. Some reporters have profiled her, but none of the stories I've seen (and can remember) quite get to what she thinks about global warming and its proper policy response. She says there is little that is certain aobut it future, but what is her best guess? We just learn that she finds a lot of 'warmists' falling short of her standards of rigor. She seems tougher on her natural friends than on her natural foes.
She, from what little I know of her, reminds me of an observation I and others have made about human nature. Most of us, to some degree, try to see the essential character aspects that define people. But there is a tendency in many of us to judge others excessively by those actions that are least typical of them. Hypothetical examples: Everyone thinks Ms. Goody is a saint, always helping others and volunteering for tough jobs and finding reasons to forgive and working hard to improve the community. But then I see her, when she thinks nobody is looking, kick a puppy. I might spread the word: "She's not really nice, not down deep. She's a sadist." One example and a liftetime of good acts erased from the popular mind just like that. Or maybe the town bully that everybody hates is spotted, in a neighboring town, volunteering in a soup kitchen or handing $10 to a homeless person. "He's not really bad," one might say. "Down deep he's a very kind guy." His reputation soars above that of the good girl who once kicked a puppy.
Some people just mistake outliers for the typical.
LATE ADDITIONS:
- LA Times – Neela Banerjee: Global warming poses most immediate threat to tropics, study finds ; Fine explanation why tropical creatures may have the hardest time even if the average temps there do not rise as fast as they do near the poles.
- Washington Post/ Capital Weather Gang – Jason Samenow: Washington, DC, to pass climate point of no return in 2047, study says; Is that credible? ; Lede says the study is groundbreaking, and cites the Post's news page yarn by Bernstein (see list above) as this post's trigger. But it also quotes expert sources who don't put much faith in the precise dates that many reporters cite.
- Chr. Sci. Monitor – Pete Spotts: Global warming: Record heat of today could be new norm in 2047, study says ; Something subtle about coverage has been bugging me, and this epitomizes it. No particularly slam on Spotts is meant here. But the study is about yearly temperature averages and their variations as global warming goes along. It does not say that there will not be days or weeks or even months during which weather is every bit as cold as has commonly occurred in the last century and a half. Readers of this hed and the lede might think the dates refer to the best guess when it is never as cool again as the hottest for the last many decades. By this study's light it is presumably possible that the near-stable tropics would be really really hot almost all the time starting in a decade or two, but even in 2075, one suspects, Washington DC could see an occasional snowstorm.
- Reuters – Alister Doyle: Shift to a new climate likely by mid-century – study ; Nice job. It occurs to me, on another note that I ought to check into on a day other than Sunday, that a short time ago there was much talk of a deemphasis on environment and particularly climate change news at Reuters.Word was that old-hand Doyle had been shuffled to a less contentious beat. But he's cropping up now and again in his old global warming haunts. Good.
- Pacific Standard – Michael Todd: The Game of Climate Whac-A-Mole Will Hit the Tropics First ; Fine, on two coounts. First he spelled Whac-a-Mole almost correctly (the 'a" should be "A" but there indeed is no K). Second, he spells out that this (see remarks on CSM story two bullets up) study is about yearly averages, not shorter-term variations.
- E&E/ClimateWire – Stephanie Paige Ogburn: In 34 years, the Earth will experience a new kind of hot — study; Solid straightforward report (most E&E reports are restricted to subscribers but, as here, some are published openly). Includes comment and perspective from noted climate analysts who are not authors of the Nature report. Its explanation of the greater variability in temperature at higher latitudes falls short – its examples of see-sawing temps are short term phenomena (ice storms in DC, heat waves in Alaska). One supposes that noisier systems tend to be noisy on many scales. But there ought to be overt declaration that, and perhaps explanation why, wider excursions on daily to weekly tempos tilt the odds toward more yearly variance as well.
Grist for the Mill: University of Hawaii at Manoa Press Release ;
*UPDATE: More on Judith Curry research. A few reporters are surely looking at this: a new paper in the journal Climate Dynamics with her as co-author. It proposes to explain the current, rough hiatus in the global warming trend as the result of a coordination of large, regional meteorological and oceanic sloshings. These include the Atlantic Multidecadal Oscillation, El Nino-Southern Oscillation, and Pacific Decadal Oscillation. Their action is being compared to a "stadium wave" in which spectator sections rise and fall in sequence, forming a wave roaring around an arena. First, here is Curry's blog on it, in which is embedded a link to the text of the paper and the Georgia Tech press release. It seems, intuitively, plausible. It also means that when the wave dies out warming will probably return wth the vigor of a hungry tiger let off its leash. In a rational world one would hope this paper is sound – it might give humanity a breather to allow construction of measures to curb greenhouse gas emissions. On the other hand (isn't there always one?), it might only lull us into even deeper torpor while the continuously accumulating thermal energy winds up for a roundhouse punch as the ocean's warmed, deep waters bloom in a killer, worldwide El Nino upwelling.
We'll watch for coverage of this. So far, not much:
- Register (UK) Andrew Orlowski: Boffins find MEXICAN WAVE pattern in random climate wobbles ; Of COURSE the Register blames boffins. It always does when science is in the news. The story goes rather off the rails loony toward its end, citing a few hypotheses making the rounds that, from the description here, look crackpot.
- Phys. Org: 'Stadium waves' could explain lull in global warming ; Pure aggregationist sloth: a press release rewrite.
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