Daybook

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reading: Sedentism and Mobility in a Social Landscape: Mesa Verde and Beyond, by Mark Varien. Varien proposes a model for understanding mobility in archaeological studies at the household level, which makes a lot of intuitive sense to me. Thinking of my Northeast Heights neighborhood as having been “continuously occupied” since its post-World War II construction would be correct, but would miss the fact that the Waldron family owned my house prior to 1993 and then we moved in. The question of why the Waldrons left and we moved in is not unimporant in understanding the nature and structure of the neighborhood. Likewise, in thinking about the effect of climate on the Anasazi, it’s worth thinking not only about the construction and abandonement of Chaco, Mesa Verde, etc., but also what was happening between those two great events. The comings and goings matter.

music: Broadway the Hard Way, the latest acquisition in my effort to acquire a whole bunch of Frank Zappa from used CD bins. It’s a marvelous romp down memory lane, with guest appearances (sort of) by Admiral Poindexter, Ollie North, and Sting:

Guest appearance by Sting on a live version of the Police B-side “Murder By Numbers” (In response to PMRC allegations that this song was written by Satan, Sting is heard to note that “I wrote the fuckin’ song!”)

shopping: Lissa had to procure a certain book Thursday night, so we went to Borders in the old Winrock Mall. The place is nearly empty, as they prepare for wrecking balls. It was weird, the central gathering point of our consumerist culture reduced to a well-tended ghost town.

Overpeck’s Consistency

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Steve McIntyre, fresh from AGU, has noticed Jonathan Overpeck talking about drought and sea level rise, inferring some newly minted marketing message:

It’s hard not to conclude that Overpeck was attuned to the market and giving them what they wanted. You want sea level – Overpeck had sea level. You want drought – Overpeck had that too. Bob Carter described the session as being like being at an evangelist’s meeting. It hardly seems coincidental that the hot-button issues should have featured so dramatically.

Note to Steve: I was on a panel with Overpeck in the spring of 2003. The main emphasis of his talk was drought and sea level. He’s been talking about drought and sea level for a long time. See, for example, 2000 Years of Drought Variability in the Central United States, with Connie Woodhouse:

The authors’ assessment of the full range of past natural drought variability, deduced from a comprehensive review of the paleoclimatic literature, suggests that droughts more severe than those of the 1930s and 1950s are likely to occur in the future, a likelihood that might be exacerbated by greenhouse warming in the next century.

That’s from 1998. Dr. Overpeck’s been consistent in emphasizing this point for a number of years.

Science and the Courts

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Read a good article this morning in Science News by Janet Raloff about science in the courts – how the 1993 Daubert decision has changed the way courts handle scientific evidence in controversies. At the heart of the piece is the different views of the two cultures – science and the law:

Scientists question, test, evaluate, and retest various hypotheses, looking for an explanation that best fits the observations, says Douglas L. Weed of the National Cancer Institute in Bethesda, Md. They’re not expecting “truth,” he notes, because they know that “uncertainty flows through science like a river.”

“Consumers of science, of which the law is one, have another use for science—to help answer whether one thing caused another,” says Weed.

The Death of UFO’s

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Dave Thomas points to an argument that is largely evidence-free but nevertheless alluring: Doug Kern at Tech Central Station on how the Internet killed off enthusiasm for UFOs:

The Internet processes all truth and falsehood in just this fashion. Wild rumors and dubious pieces of evidence are quick to circulate, but quickly debunked. The Internet gives liars and rumor mongers a colossal space in which to bamboozle dolts of every stripe — but it also provides a forum for wise men from all across the world to speak the truth. Over the long run, the truth tends to win. This fact is lost on critics of the blogosphere, who can only see the exaggerated claims and gossip. These critics often fail to notice that, on the ‘net, the truth follows closely behind the lies. A great many of us accept Internet rumors and hoaxes in exchange for fast access to the truth.

Diurnal Temperature Range

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OK, here’s something I don’t get: a new paper in GRL by Russell Vose at the National Climatic Data Center suggesting the decrease in the diurnal temperature range slowed dramatically from 1979-2004. Maybe some of you climate types can ‘splain this?

(Backstory for non-climate wonks: The “diurnal temperature range” is the difference between the daytime high and nighttime low. My understanding, based on Karoly et al. in 2003 in Science, was that greenhouse warming would be expected to reduce the DTR by disproportionately increasing the overnight low temperatures. That’s exactly what I see happening in my own little corner of the world, with overnight lows warming a lot more than daytime highs. In other words, DTR is part of my day-to-day experience of global warming. It means my morning bike rides are a bit more comfy.)

Delaying Doubling

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Kevin Vranes on the reality of Kyoto and Montreal:

The real consensus we need to reach here is whether slowing GHG increases is worth it or not. Kyoto has always been close to irrelevant climatologically and while I feel the pain of those making the “it’s a start, a necessary first step” argument, I have never been too sympathetic to it. Does it make a difference whether we forestall achieving 2xCO2 by a decade or two? It may be a depressing answer to some, but my answer is, “I doubt it.”

Bottle Gourd

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I did not know that the bottle gourd was the first domesticated plant in the Americas, 10,000 years ago. (If you’d asked me, I would have guessed maize. Wrong.)

It’s what archaeologists call a “utility species” – domesticated not for food but for non-edible usefulness. (Dogs also qualify as a “utility species.”) Bottle gourd was good for making containers before the development of ceramics.

It’s always been a bit of a mystery as to how bottle gourd, a native of Africa, got here, but a new paper this week in the Proceedings of the National Academy offers up evidence suggesting early immigrants must have brought it with them from Asia. David Erickson and colleagues matched up the DNA of bottle gourd found at archaeological sites in North and South America with its Asian and African relatives to dry the necessary lines on the map.

Lewis Fry Richardson

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Reading John Houghton’s Global Warming: The Complete Briefing this evening, I was reminded of one of my favorite episodes in the history of science: Lewis Fry Richardson and the first numerical weather forecast.

Richardson was of that era that ended with the burst of modernism in the early 20th century – a generalist, dabbler in many things. A pacifist, he was working as an ambulance driver in World War I when he envisioned the calculations necessary to forecast the weather. “With much painstaking calculation with his slide-rule,” Houghton writes, “he solved the appropriate equations and produced a six-hour forecast.” The problem, as Houghton notes, was that it took him six months of work, which doesn’t really meet the timeliness requirements of a usable forecast. (He also seems to have gotten it wrong, I’m told, not understanding the importance of the relationship in his model of grid size to time step.)

But the coolest part is the solution he envisioned to get a forecast done in a reasonable time. Houghton again:

To apply his methods to real forecasts, Richardson imagined the possibility of a very large concert hall filled with people, each person carrying out part of the calculation, so that the integration of the numerical model could keep up with the weather.

I riffed on this last year in a story about the new Red Storm supercomputer (sub. req.), which uses an architecture conceptually quite similar to Richardson’s.

Richardson just wanted a way to forecast the weather, and he could not possibly have imagined much of the computer technology at Red Storm’s heart.

But the basic concepts he envisioned— a way for many calculations to swiftly be shared and integrated into a useful whole— lie at the heart of the machine to be built at Sandia.

Cray Inc. is building the $90 million Red Storm for Sandia’s nuclear weapons work. It will use 11,648 computer chips identical to the ones that power desktop computers.

The chips will be tied together in an architecture that bears a striking resemblance to Richardson’s idea.

“The guy was so far ahead of his time,” said Dave Gutzler, a University of New Mexico climate researcher and aficionado of Richardson’s work. “Almost nobody understood the significance of what he was doing.”

Careful What You Wish For

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Forests are a good thing, right? And reversing deforestation is a smart approach to climate change – locking all that carbon back up in trees, right?

A new paper out of Lawrence Livermore throws an odd monkey wrench into the conventional wisdom, using model simulations to conclude that grassland cools while forest warms:

We find that global replacement of current vegetation by trees would lead to a global mean warming of 1.3°C, nearly 60 percent of the warming produced under a doubled CO2 concentration, while replacement by grasslands would result in a cooling of 0.4°C. It has been previously shown that boreal forestation can lead to warming; our simulations indicate that mid-latitude forestation also could lead to warming. These results suggest that more research is necessary before forest carbon storage should be deployed as a mitigation strategy for global warming.