Comments

1
Your link to the study of tropical cyclones is not accessible to the public, it is behind a UW login wall.

Is the paper you linked to this one in Nature Geoscience?

The abstract unfortunately doesn't include a confidence interval or p-value for the fit between storm intensity data and surface sea temperature readings.
2
Yeah, sorry about that, I thought I updated that link. The original paper is here, behind a paywall: http://science.sciencemag.org/content/30…

But you can find a .pdf version with responses here: http://s3.amazonaws.com/academia.edu.doc…
3
The s3 link to the pdf is broken, too: it's returning an error saying Access is Denied because the Request has Expired.
4
Er, from the paper (emphasis mine):

Figure 3 shows that in each ocean basin time series, the annual frequency and duration of hurricanes exhibit the same temporal characteristics as the global time series (Fig. 2), with overall trends for the 35-year period that are not statistically different from zero. The exception is the North Atlantic Ocean


and:

Decadal variability is particularly evident in the eastern Pacific, where a maximum in the number of storms and the number of storm days in the mid-1980s (19 storms and 150 storm days) has been followed by a general decrease up to the present (15 storms and 100 storm days). This decrease accompanied a rising SST until the 1990–1994 pentad, followed by an SST decrease until the present. In the western North Pacific, where SSTs have risen steadily through the observation period, the number of storms and the number of storm days reach maxima in the mid-1990s before decreasing dramatically over the subsequent 15 years. The greatest change occurs in the number of cyclone days, decreasing by 40% from 1995 to 2003.


you summarize this as:

it’s also true that that the frequency and intensity of tropical cyclones are increasing as ocean temperatures rise in lockstep with global warming.


I do not think this is a reasonable summary of the paper's findings, particularly when applied to our local region.
5
Point taken about the diction "lockstep" and it looks like I misread the paper w/r/t frequency -- I'll see if I can change that in the post. I stand by my claims about intensity, though, and my general conclusion:

"In contrast, hurricanes in the strongest categories (4 þ 5) have almost doubled in number (50 per pentad in the 1970s to near 90 per pentad during the past decade) and in proportion (from around 20% to around 35% during the same period). These changes occur in all of the ocean basins" (Webster 2004)

...also supported by a paper last year by Mei et al: "Our observational analysis has thus revealed that the seasonal mean typhoon lifetime peak intensity is primarily controlled by two distinct factors: intensification rate, which in turn is strongly affected by local upper ocean temperatures, and intensification duration, which in turn is influenced by large-scale modes of climate variability..."

http://advances.sciencemag.org/content/1…
6
There has indeed been an increase in intensity in all basins, and intensity is indeed affected by SST, but SST has has decreased in some basins while intensity has increased.

The global average increase in intensity may yet be shown to have been driven by anthropogenic warming, but the evidence suggests that if this is the case, it is not happening via the mechanism of SST (which is what produced it in the computer models that initially gave rise to the hypothesis that global warming would produce more and stronger storms)

This is all laid out much better in the paper, of course. It's a good read; thanks for the pointer!
7
Webster et al. 2005, comment by Chan, response to comment by the authors
for you internet bozos who can't make your links work

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