A couple of days ago there was a guest post from Russ Steele citing a California study “Feeling the Heat” on global warming that just didn’t seem to add up. One of the stations cited as having climate change related warming was Reno, NV. So, I decided to do a field experiment to test this. The results show clearly that UHI exists in Reno.
Here is what Russ wrote a couple fo days ago:
Feeling the Heat was published by Environment California a non-profit group a few weeks ago, claiming 2007 was the tenth warmest year on record and that the mountain west was experiencing above-average temperatures. Full report here: Download feeling_the_heat_ca.pdf One of the examples given for the high western temperatures was Reno Nevada with a average temperature of 55.3 degrees in 2007, four degrees higher than the 30 years average temperatures from 1971 to 2000.
…Up front in the EC report the author dispatches UHI as having any influence on the climate change, citing studies by Easterling, PD Jones and Parker…
Well I decided to test this myself tonight, since I’m driving through Reno on my return home, I arranged an overnight stay. With me is my NIST calibrated data logger, NIST Calibrated temperature probe, a vehicle mounted Gill IR shield, my laptop computer, and my trusty vehicle. See my previous post “Road Kit”
I chose Virginia Street as the transect route, since it remains relatively straight, level, and crosses all of Reno, including the built up southern suburbs and downtown. It is the original “main street” for Reno.
Here is the result of my South to North transect driving Virgina Street overlaid on a Google Earth image oriented to match the timeline of the transect:
Click for larger image
The weather tonight was perfect. Light winds, clear skies.
Here is the data from the Reno airport ASOS, which also happens to be a USHCN climate station:
Time Temp Dew RH Wind Wind Vis WX Sea Level Altimeter Station
Point Dir Speed Pressure Setting Pressure
(PDT) (f) (f) (%) (mph) (miles) (mb) (inches) (inches)
1:55 am 44 25 47 CALM 10.00 CLR 1023.0 30.30 25.788
12:55 am 48 24 39 CALM 10.00 CLR 1023.4 30.31 25.797
11:55 pm 51 23 33 WSW 3 10.00 CLR 1023.7 30.31 25.797
10:55 pm 54 23 30 S 6 10.00 CLR 1024.1 30.32 25.805
For those interested, I have the raw source data from my datalogger in CSV form for the South to North Reno transect here. (PDF)
Note the placement of the airport, which has it’s ASOS weather station used in many climate studies essentially in the north end middle of the airport. The Reno UHI bubble does extend into this area.
Click for a larger image
I also did a reverse transect, driving the same route in reverse immediately. Plus a route near the airport. I’ll have more tomorrow, its 2AM and I’m tired.
Jeff Id inquired in comments “how is it mounted to the car/” Here is the answer:
The temperature sensor (inside the Gill IR shield) mounted on the vehicle using an improvised window mount.
Also, the time of night that I made the transect (11:15PM to 11:39PM) allowed me to maintain a nearly constant speed during the transect due to the lack of traffic. Plus Virginia street has stoplights set for all green unless there is cross traffic. I was fortunate to have to stop only once during the entire drive, and that was in the downtown area. I kept an eye on the temperature reading during the stop, and no change was recorded.
I’ll have a complete post in the next day, still catching up from my trip.