Dr. Roger Pielke Sr. reports that there’s a new paper out with a fun title, based on that famous for Robert A. Heinlein quote : Climate is what you expect, weather is what you get.
“The Climate Is Not What You Expect” By S. Lovejoy and D. Schertzer 2012
The abstract reads: (emphasis added by Pielke)
Prevailing definitions of climate are not much different from “the climate is what you expect, the weather is what you get”. Using a variety of sources including reanalyses and paleo data, and aided by notions and analysis techniques from Nonlinear Geophysics, we argue that this dictum is fundamentally wrong. In addition to the weather and climate, there is a qualitatively distinct intermediate regime extending over a factor of ≈ 1000 in scale.
For example, mean temperature fluctuations increase up to about 5 K at 10 days (the lifetime of planetary structures), then decrease to about 0.2 K at 30 years, and then increase again to about 5 K at glacial-interglacial scales. Both deterministic GCM’s with fixed forcings (“control runs”) and stochastic turbulence-based models reproduce the first two regimes, but not the third. The middle regime is thus a kind of low frequency “macroweather” not “high frequency climate”. Regimes whose fluctuations increase with scale appear unstable whereas regimes where they decrease appear stable. If we average macroweather states over periods ≈ 30 years, the results thus have low variability. In this sense, macroweather is what you expect.
We can use the critical duration of ≈ 30 years to define (fluctuating) “climate states”. As we move to even lower frequencies, these states increasingly fluctuate – appearing unstable so that the climate is not what you expect. The same methodology allows us to categorize climate forcings according to whether their fluctuations decrease or increase with scale and this has important implications for GCM’s and for climate change and climate predictions.
The conclusion reads:
Contrary to [Bryson, 1997], we have argued that the climate is not accurately viewed as the statistics of fundamentally fast weather dynamics that are constrained by quasi fixed boundary conditions. The empirically substantiated picture is rather one of unstable (high frequency) weather processes tending – at scales beyond 10 days or so and primarily due to the quenching of spatial degrees of freedom – to quasi stable (intermediate frequency, low variability) macroweather processes. Climate processes only emerge from macroweather at even lower frequencies, and this thanks to new slow internal climate processes coupled with external forcings. Their synergy yields fluctuations that on average again grow with scale and become dominant typically on time scales of 10 – 30 years up to ≈ 100 kyrs.
Looked at another way, if the climate really was what you expected, then – since one expects averages – predicting the climate would be a relatively simple matter. On the contrary, we have argued that from the stochastic point of view – and notwithstanding the vastly different time scales – that predicting natural climate change is very much like predicting the weather. This is because the climate at any time or place is the consequence of climate changes that are (qualitatively and quantitatively) unexpected in very much the same way that the weather is unexpected.
Pielke writes:
There are a series of informative comments on this paper by Judy Curry, Philip Richens, Shaun Lovejoy and others on the weblog All Models are Wrong post
In the insightful comment by Shaun Lovejoy on that weblog, he does write on one issue that I disagree with. Shaun writes
“….deterministic models (GCM’s) reproduce only weather and macroweather statistics (they do this quite well)”.
I agree on weather, but not on macroweather. Macroweather prediction has shown little, if any skill ; e.g. see the papers listed in my post
Kevin Trenberth Was Correct – “We Do Not Have Reliable Or Regional Predictions Of Climate”
Read Dr. Pielke’ whole post here.
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When we finally determine and define a consensus “ideal climate” for Earth’s biosphere, we will have a baseline to which we can assign an anomaly. Until this is done, are we not, just whistling in the wind? Why has this debate never arisen above the noise. GK
Jim R says:
June 30, 2012 at 8:45 am
> Heinlein had some nasty right wing libertarian thoughts. I’ll go with Twain. He liked folk.
Wow, I’d love to see your school research papers. Oh well, in the same vein, Twain is known for plenty of weather quotes, he just didn’t write this one.
If Anthony gives you a chance, I’d like to see your definition of left wing libertarian. We tend to use a grid with economic freedom on one axis and personal freedom on another and your wings don’t work so well on that.
Better yet, get back on topic….
I think it’s important to look a climate changes on pretty much all time scales. Slavish adherence to particular ones, e.g. 30 years, means that you’ll miss things like the Great Pacific Climate shift in the 1970s or our entry into a period of active Atlantic hurricane seasons in 1995.
The climate for each region changes usually four times a year even on the equator. But it is not rigid, you can have all sorts of unusual weather patterns like an Indian Summer and I am absolutely sick of these people who don’t know the basic meteorology. Have they heard of rain shadows? Places within a mile of one another, one gets lots of rain and it misses others. My friend lives about 1.5 km from me in a valley beneath where I live and it would be peeing down with rain where she lives and hardly a drop where I live. We are 3500 ft absl she’s 3250 or so. When it snows it settles where I live, but where she lives it doesn’t because of the UHI effect. Look we lived in Bermuda a narrow group of islands in the South Atlantic. Cold in winter, humid and hot in Summer. We depended on rain water tanks to store water. I lived on Blue Hole Hill a high area looking over the causeway to the island of St.George and airport/American air force base, etc. Dieing for rain, and some of us buying water. We’d watch the rain clouds and shadows and water spouts all around us and then nothing hit land. Yesterday the NSW weather forecast was possible snow on higher peaks and a cold blast. Well it is one of the warmest days we’ve had so far. Somewhere it will be snowing no doubt, but certainly not here. And we are a temperate zone, not like further down the tablelands towards Tamworth that is on average 5C-7C warmer than us – generally. All we need is a big Plinian volcanic eruption say Mt.Vesuvius to make us remember ‘Mother Nature’ controls us whether we will except that or not.
Here’s a link to a compilation of quotes from Heinlein:
http://en.wikiquote.org/wiki/Robert_A._Heinlein
Take a look at “The Man That Corrupted Hadleysburg,” The Mysterious Stranger,” and “Captain Stormfield’s Visit to Heaven.” They are hardly folksy. Heinlein’s quotes actually contain more “up with people” sentiments.
Jim R says:
June 30, 2012 at 8:45 am
> Heinlein had some nasty right wing libertarian thoughts. I’ll go with Twain. He liked folk.
Oh dang! How could I forget?
Do you include “folk” with “congressmen”?
One from http://www.twainquotes.com/Congress.html :
While mentioned there, many of Twain’s best weather quotes refer to New England and come from a speech at the New England Society’s Seventy-First Annual Dinner, New York City, Dec. 22, 1876. It’s preserved at http://www.islandnet.com/~see/weather/arts/twain1.htm :
I think he would have liked Heinlein.
And, I don’t hold New England thunderstorms in much respect, My CMU days in Pittsburgh had good storms with all the steep valleys for thunder to bounce between.
One major exception – thunderstorms above treeline in NH’s White Mountains. Let’s send our congresscritters there on a fact finding mission.
I bet Jim R probably thinks George Washington had some “nasty, right wing libertarian” ideas. Afterall, GW wrote that government is not reason, it is force.
And while there seem to be people out there who believe that the 2nd Amendment was written so that Americans could enjoy their duck and deer hunting, the fact is that the writers understood that for a free Republic to exist, a government could not possess a monopoly on force.
Makes one wonder when believing in the Constitution and its Amendments denotes someone with nasty, right wing libertarian ideas.
timg56 says:
July 2, 2012 at 1:56 pm
> Makes one wonder when believing in the Constitution and its Amendments denotes someone with nasty, right wing libertarian ideas.
It’s probably all those pasty, left wing fascists that were around in between that make Jefferson, Franklin, and all their cronies so evil.