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Filed under: — gavin @ 24 December 2011

Two slightly off-center topics that Realclimate has covered in the past have recently come up again. The first is an analysis of Freakonomics by statisticians Andrew Gelman and Kaiser Fung in American Scientist, while the second is a recent reimagining of Washington crossing the Delaware.
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Copernicus and Arrhenius: Physics Then and Physics Today

Filed under: — eric @ 21 December 2011

There was a really interesting article in Physics Today this past October on the parallels between the slow acceptance of the idea of anthropogenic climate change and of the idea that the earth circles the sun.
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Climate cynicism at the Santa Fe conference

Filed under: — group @ 19 December 2011

Guest commentary by Mark Boslough*

The Third Santa Fe Conference on Global and Regional Climate Change was held during Halloween week. It was most notable for the breadth of opinion — and the span of credibility — of its speakers. I have long complained about the lack of willingness of most contrarians to attend and present their arguments at mainstream scientific conferences. After three years of convening climate-related sessions at AGU, I have yet to receive an abstract that argues against anthropogenic global warming. Such presentations can usually only be seen at conferences held by the Heartland Institute. There isn’t much chance of a mainstream scientist attending a meeting organized by a political think tank known for its anti-science activism, so opportunities for interaction between the groups are rare.
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Curve-fitting and natural cycles: The best part

It is not every day that I come across a scientific publication that so totally goes against my perception of what science is all about. Humlum et al., 2011 present a study in the journal Global and Planetary Change, claiming that most of the temperature changes that we have seen so far are due to natural cycles.

They claim to present a new technique to identify the character of natural climate variations, and from this, to produce a testable forecast of future climate. They project that

the observed late 20th century warming in Svalbard is not going to continue for the next 20–25 years. Instead the period of warming may be followed by variable, but generally not higher temperatures for at least the next 20–25 years.

However, their claims of novelty are overblown, and their projection is demonstrably unsound.

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  1. O. Humlum, J. Solheim, and K. Stordahl, "Identifying natural contributions to late Holocene climate change", Global and Planetary Change, vol. 79, pp. 145-156, 2011.

AGU 2011: Day 5 and wrap-up

Filed under: — group @ 11 December 2011

(Day 1)(Day 2)(Days 3&4)

After 5 days, there is a definite slowdown in energy, desire to ask questions and attendance. But there were still a lot of good talks to be seen. Perhaps most relevant here were a few sessions talking about initial results from the CMIP5 models and the data with which they are being assessed. Overall, most comparisons to the CMIP3 models showed that despite substantial improvements in resolution, completeness, and scope, the CMIP5 models do not show any dramatic differences at the broad-scale diagnostics (global means etc.).

This is not particularly surprising, since it is expected that the importance of the new simulations will be seen in the differences between model types (i.e. including carbon cycles, atmospheric chemistry etc.), or in new kinds of diagnostics from say, the initialized decadal predictions, that weren’t available before.

Looking back at the whole meeting (20,000+ scientists, dozens of simultaneous sessions), it is perhaps worth noting the reasons why such meetings are so important. Obviously, no-one can see everything that is relevant to their research, or talk to everyone they might want to, but there is a lot that can be seen and absorbed much more efficiently than would be possible at home. The social aspect of conferences is also important – beer is an essential lubricant for geophysicists it seems. More important than the sessions are often the chance encounters on the escalators or corridors. Many people get to meet in person who only ever emailed – and this includes other bloggers as well as scientists. We met Eli Rabett, John Cook (Skeptical Science), Zeke Hausfather, Kate @ ClimateSight, Steve Easterbrook, and many others who are only known by their screen names and comments. Many of the scientists whose work has been discussed here recently were also present – Andreas Schmittner, Robert Rohde (of BEST), Jim Hansen, Ben Santer, Roy Spencer, along with many, many first timers whose work will become more prominent. The palpable sense of excitement at the directions the science is taking is very much driven by the bright ideas and new approaches being generated by the younger scientists – including undergraduates and graduate students. And it is the serendipitous encounters with these new voices that are the most unanticipated (and unplanned) benefits of these meetings. This doesn’t happen with Skype unfortunately.

We know that we didn’t see everything we wanted to, so if any other attendees are reading this, we encourage them to point out in the comments any particular highpoints they came across – especially if the talks were part of those broadcast, or if the poster is available on-line.

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