A lot of hysteria this week from the usual scoundrels, about CO2 driven hot nighttime temperatures in Phoenix.
The National Weather Service reports that nighttime temperatures outside the metropolitan area are 7-13 degrees cooler (as anyone who lives there already knows)
The effects of the UHI are most pronounced during the summer (June-July-August) months. In a simple comparison, average high and low temperatures from Maricopa, AZ and Phoenix Sky Harbor International Airport were compared (Figures 2 and 3). Little difference exists between the high temperatures from 1961 through 2007; however, low temperatures have trended warmer at Sky Harbor as compared to Maricopa, indicative of the existence of a strengthening UHI. Similar results have been found by Brazel et al. (2000), who compared temperature observations at several urban stations in the PMA (Phoenix, Mesa, and Tempe) to a rural station outside the PMA (Sacaton). The average minimum May temperature at the urban locations displayed an apparent upward increase through the time series (1910 through 2000), which was attributed to the urban growth of the region. By the end of the series, there was a +4 to 7 ºC (7 to 13 ºF) difference between the urban minimum temperatures and the rural minimum temperatures.
There must be a CO2 bubble sitting over the city.
and according to the rules of climate science…
…you must adjust temp reading up to allow for UHI
Just like GISS do in Reykjavik, Lat!!
http://notalotofpeopleknowthat.wordpress.com/2012/11/09/giss-double-up-on-reykjavik-temperatures/
When I asked Reto Ruedy to explain it, he said it happens a lot. 1204 out of 2933 cases!
http://notalotofpeopleknowthat.wordpress.com/2012/11/11/giss-uhi-adjustments-add-to-warming-trend/
He even bragged that their adjustment was small compared to the one GHCN had already made.
good grief!……thanks Paul, I didn’t read those before!
Showing the urban temp has gone up while the rural has not is clear enough. So it’s pretty certain this explanation will go right over the heads of the scoundrels (my inner voice says they are spoiled children, just trying to get your goat and make you look bad to all the other spoiled children in the Insane Left; if you’re referring to the scoundrels that comment on your blog, I think you coddle them too much).
Reblogged this on CraigM350.
Yup, they adjust the rural temps up to match the UHI….it’s called “homogenization”
Conversly, isn’t it strange that the fact that higher UHI minimum temperatures in a metropolitan area during cold winters are actually beneficial and energy saving but never appreciated ???
I have carefully and repeatedly measured UHI here in Phoenix and is indeed between 7 and 10 degrees. I live in the south east part of Phoenix and simply wait until sunset to minimize pure radiant heating – mount a temperature logger on my car antenna and drive out to the Indian reservation and drive back. I have done this time and time again and it is amazing the difference in temperature and often times humidity between a built-up urban area, and open prairie/desert.
I remember a night in July, 1985 when it was maybe 102 in Tempe at 10 pm. I drove south on I-10 past Ahwatukee (nothing out there back then other than the golf course) and it must have been 20 degrees cooler.
Man made parking lot warming.