Statistics

Claiming To Be Able To Blame Weather Events On Global Warming

This is not a big story, but it’s worth highlighting because of the pernicious effects of science journalism, which suffers from the same faults as political journalism. Emphasis on extremes, cheerleading, opinion masked as fact, over-certainty, no deviance from official narratives, and so on and so forth.

We’ll walk through one of these pieces for the fun of it and see what lessons can be drawn. (Thanks to Benny Peiser at the Global Warming Policy Foundation for the tip.)

On the official American Physical Institute site is the article “Pinpointing the Roots of Extreme Weather Events“, which boasts, “A statistical method for fingerprinting the patterns of heat waves and cold spells could reveal whether climate change caused an extreme weather event.”

This is something regular readers will be familiar with. I mean, claims to be able to identify whether some bad (never good) weather event can be blamed on global cooling a.k.a. global warming a.k.a. climate chance a.k.a. whatever. We saw in the paper “The Climate Blame Game: Are we really causing extreme weather?” this can’t be done with any reasonable degree of certainty.

How about here?

Article starts by saying it was hot out west somewhere, and that the temperature was “unprecedented”. By which they could have only meant it was slightly above the small number of records kept over a limited number of years using modern measuring equipment. Anyway, there is our “bad” event.

We now have to blame the bad—never good!—event on people, else it becomes a non-story. The author obliges: “Climate models indicate that extreme heat waves—prolonged periods with sustained temperatures above average—will likely occur more often and with increasing severity if Earth’s overall temperatures continue to rise.”

This “likely” is transformed into near certainty by appearing next to the following sentence, “But teasing out whether climate change caused a specific heat wave or cold spell remains difficult.”

Impossible, I say, because the climate models can’t be trusted. (More on this another day: even modelers are being forced to publicly admit this.)

Skip that. Author says IDing global cooling as the culprit

could become easier with a new method from statistical physicists Valerio Lucarini of the University of Reading, UK, and Vera Gálfi of Uppsala University, Sweden. Their method allows the user to uncover what set of characteristics define an extreme weather event for a specific climate and then to use those fingerprints to determine whether a real event, such as any of the 2021 heat waves, was caused by the natural variability of the climate or by global warming.

Okay, sounds interesting enough. Maybe if it took into account the gross over-certainty of the models’ future forecasts something good could come out of it.

The ability to make these inferences comes, Lucarini says, because of the similarity of the patterns of simulated extreme events. The analysis shows that these events all sit in the same “universality class”—a term for a collection of things that have converging properties…

The predictive power of the model also sets it apart from others that aim to pinpoint the cause of a specific extreme climate event. Lucarini says that other methods are largely empirical, meaning that the tools can indicate the likelihood that a past extreme event was caused by climate change but cannot predict the probable occurrence of future such events. “Our methodology allows us to do that,” he says.

The author also says the method uses the same kinds of climate models the IPCC uses. So this is serious stuff! Does it work?

The team tested the model for two extreme temperature events from 2010: a month-long heat wave in Russia, where temperatures soared to 20 °F (11 °C) above average, and a cold spell in Mongolia, which brought heavy snow and temperatures of -58 °F (-50 °C)…The team found that both events were expected from the natural variability of the climate.

Say, it seems their method does work. Let’s go and look at the actual paper and see what’s what. It’s the peer-reviewedA large deviation theory-based analysis of heat waves and cold spells in a simplified model of the general circulation of the atmosphere” in the Journal of Statistical Mechanics: Theory and Experiment.

I’ll skip all the probability (which any trained statistician can follow with ease) and focus on the physical model used, and which is key, and which the press piece said was like that used by the IPCC.

Compared to a full atmospheric general circulation model, moist processes are omitted, and simple parameterisations are used to account for the effect of friction (Rayleigh friction), diabatic heating (Newtonian cooling), and diffusion…

We run the model in a simple symmetric setting (usually referred to as an aquaplanet), i.e. without orography. We remove the annual and diurnal cycle, and use a symmetric forcing with respect to the equator…

Ah. A toy. The model is a toy, resembling our real atmosphere and planet in the same way the spinning globe on your desk resembles the plate tectonics of the real earth. If the globe was one big ocean.

So they ran their toy model, a not unfamiliar practice in physics, and not useless to learn from, and discovered the toy had certain statistical properties.

Since the toy has nothing really to do with the actual atmosphere, its statistics won’t either. Maybe the technique of drawing those statistics might someday be useful if actual models become good enough to rely on. Until then, it’s all, as they say, academic.

Yet it will still be difficult for most to not draw the conclusion that Something Important Happened Here, and that global cooling etc. is a problem. Which is the point of the news article.

I don’t mean to suggest the motives of all involved were anything less than earnest. I do mean to say that we could do with a lot less journalism.

Subscribe or donate to support this site and its wholly independent host using credit card or PayPal click here

Categories: Statistics

12 replies »

  1. “The author obliges: “Climate models indicate that extreme heat waves—prolonged periods with sustained temperatures above average—will likely occur more often and with increasing severity if Earth’s overall temperatures continue to rise.” ”

    As an ex-weatherman I can tell you that Climate Models can only predict AVERAGE weather – after all, that is what Climate is. Nothing more – nothing less.

  2. JohnM: I totally agree. People forget climate is nothing more than average weather, by definition.

    A question that no one ever answers: If CO2 is EQUALLY distributed around the globe, implied by the past use of one VOLCANO to measure at, then warming should be EQUAL, shouldn’t it. Answer: THEY LIED. (After they put up sensors, they admitted CO2 IS NOT equal and is seasonal, so yes, they lied.)

    It’s not opinion masks as facts. The media is that stupid and evil and does not care.

    Again, answer to “whether climate change caused an extreme weather event” is NO NO NO NO NOT. Manmade climate change is a myth, a political lie, etc, so IT CANNOT DO SO. There, clarified.

    global warming aka Political propaganda by Marxists

    By unprecedented, it means the reporter was too dam lazy to check the facts. Nothing more. And the reporter can dig out their crystal ball, don the fortuneteller outfit and rip off idiots like a commercial fortuneteller does. It also means the reporter is so self-absorbed that it believes the world began when it was born.

    Forget the models. We need something besides idiots for reporters and something besides propaganda for news. We can then consider models.

  3. The IOC (International Olympic Committee) is reporting from Tokyo that temperatures in Japan are averaging significantly higher than during the previous Japan Summer Olympics held in 1964. This may be a consequence of Global Warming – or – could be due to the 1964 Summer Games being held in October ~ while the games this year are in July. || https://www.loc.gov/rr/main/olympics/dates.html

  4. The thing I find annoying about the argument used by the Climate Alarmists that every “unusual” weather event is defacto proof of climate change is that the instant you point out a cooler than normal summer weekend and say “where’s the global warming?” they always retort with; “wEaTHer IsN’t cLImAtE u idIOt!”

  5. “The team found that both events were expected from the natural variability of the climate.”

    Of course it’s always possible that they are completely wrong and that both or either is due to climate change. My recollection of how science works is that you make a prediction and then test to see if it’s true. In this case, they didn’t make a prediction, they just came up with a model and announced the results. We are no closer to knowing how good their model is than we were before they started. And neither are they. What an idiotic process.

  6. The climate terror dopes are desperate because they’ve been superseded by a more effective plague terror campaign that produces not only more visceral fear but the chance to inject billions of dupes with gene altering nanoscheiss that turns men into obedient zombies. Like buggy whip makers horrified of the tin lizzie — their dollars dry up. Progress!

  7. This is INTOLERABLE!

    Every cloud must carry a CO2-free passport!

    We will fire missiles containing a vaccine into the air if they do not comply.

  8. Climate change is like the bat flu. Trust the science. No, not those scientists but these ones. 99% agree, therefore it’s true. Ignore the fact that scientists and doctors promoted smoking 70 years ago. Ignore the fact that food scientists wrongly blame fat instead of sugar for obesity. C’mon, have faith in science. Stop being such a heretic.

Leave a Reply

Your email address will not be published.