It's microsite influences

It's microsite influences

U.S. weather stations have been located next to exhaust fans of air conditioning units, surrounded by asphalt parking lots, on blistering-hot rooftops, and near sidewalks and buildings that absorb and radiate heat. 89 percent of the stations fail to meet the National Weather Service’s own siting requirements that stations must be 30 metres away from an artificial heating or radiating/reflecting heat source. (Watts 2009)

Comments 1 to 4:

1. Mizimi at 07:31 AM on 6 September, 2009
   An idle thought....we tend to think of 'bad' stations giving higher readings than 'good' stations as they respond to surrounding heat emitters such as buildings.
   In cold weather the opposite can occur...the 'bad' stations will respond more slowly to increasing T due to the thermal inertia of those same buildings. In other words, the T swing max-min could be greater in the 'bad' stations but dis-appears in the averaging process.
   So maybe there is an element of self-compensation here which could be determined by looking at more detailed data.
2. psilax at 01:29 AM on 6 February, 2010
   Questions: 1) The belgian media jumped on a result similar to what is posted on http://surfacestations.org/ of summer 2009 (no source reference in Belgian media) in which it seems that a lot of american surface stations have a deviations of more than 1°C and that for some "accurate" surface stations the temperature has been decline the last 100 years. Is this already incorporated in the graphs above? (No post date of the graphs).
   2) Why do your graphs only go back to 1980 while other stations have data going back more than 100 years on the graphs of surfacestations.org?
3. Chris G at 07:22 AM on 1 September, 2010
   psilax,
   Re. #2, a good question. I looked up the Menne article and the Watts 2009 article to which it is a response. Watts suggests two driving causes for the upward bias of temperatures: The change in paint spec in 1979 and the introduction of the new type of thermometers in the 1980s. I suspect that Menne, et al, restricted their period of reporting to that which Watts was concerned about.
4. Chris G at 08:27 AM on 1 September, 2010
   For what it's worth, Watts put his three different boxes closer to each other than I would have, and put the newer paint spec one in the middle. That puts the one he expects to find higher temperatures in between two, too-close, bodies that both reflect SW and radiate LW.
   
   I can't predict what difference that made, but for someone really concerned about siting of instruments, he introduces his own siting problems.

Post a Comment

Political, off-topic or ad hominem comments will be deleted. Comments Policy...

You need to be logged in to post a comment. Login via the left margin or if you're new, register here.