David Parker has published a new, more detailed analysis in the latest Journal of Climate arguing that the urban heat island effect is not responsible for the measured global warming trend. As in his earlier work on this, Parker compared windy to non-windy days:
The trends in temperature are almost unaffected by this subsampling, indicating that urban development and other local or instrumental influences have contributed little overall to the observed warming trends.
(Roger Pielke Sr. has thoughtfully disagreed with Parker on this question in the past, so I look forward to his comments on the new Journal of Climate paper.)
* With a respectful tip of the Le Blog chapeau to Harry Shearer, who has added a new “News of the Warm” feature to his weekly radio show.
John-His abstract reads almost identically to his Nature paper. I will comment further when I read his complete article to determine if he addressed the issue of a warm bias on light wind nights (regardless if they are rural or urban sites) which we documented in
Pielke Sr., R.A., and T. Matsui, 2005: Should light wind and windy nights have the same temperature trends at individual levels even if the boundary layer averaged heat content change is the same? Geophys. Res. Letts., 32, No. 21, L21813, 10.1029/2005GL024407.
http://blue.atmos.colostate.edu/publications/pdf/R-302.pdf
and discussed on the Climate Science weblog (e.g. see
http://climatesci.atmos.colostate.edu/2006/01/23/why-there-is-a-warm-bias-in-the-existing-analyses-of-the-global-average-surface-temperature/).