How not to measure temperature, part 21

The recent photo submissions at have demonstrated that many NOAA/NWS climate monitoring stations feature convenient close-by vehicle parking.

Not to be outdone, the Paso Robles USHCN Climate Station of Record features freeway on-ramp access to California’s Highway 101. The weather station is just feet from the street, with the temperature sensor placed just high enough to catch full view of vehicles over the fence.

paso_robles.jpg My thanks to surfacestations,org volunteer Ed Hahn for this photo. His complete photo essay is available here

Here is the NASA GISS plot for Paso Robles:


Curiously the GISS database still classifies this station as a “rural area”.

I find it interesting that the temperature was trending down in the 70’s then a huge offset occurred just about 1980. I wonder if that was when the freeway access was added? Nothing in the MMS records seem to indicate a station move or other change at that time. Or maybe that’s when somebody got the bright idea to pour a concrete slab under the the station?

From NOAA’s own siting specs: “The sensor should be at least 100 feet from any paved or concrete surface.”

Close enough for government work…

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July 12, 2007 1:56 am

Well, it DOES say to put it over a surface that “The ground over which the shelter [radiation] is located should be typical of the surrounding area.”
In a lot of the metro areas, pavement and parking lots ARE typical. So shouldn’t the requirements be updated to note that, and supercede the distance required from paved or concrete surfaces?

July 12, 2007 4:41 am

Hey, there’s a tree in the frame, so it’s rural. 😉

July 12, 2007 4:46 am

…HA…that is all kinds of awesome.

Eric Hammer
July 12, 2007 6:00 am

I love it! Keep up the good work. There is no substitute for the truth. Whether people listen to the truth or not is another matter.
What would make this especially interesting is if you were to use the “Google Earth” program and map the locations of these stations. Google Earth provides an almost scary level of detail and would provide good visual impact for all to see.
Visit the link for the additional photo’s at the bottom of the post, Google Earth is already being used.

John Goetz
July 12, 2007 9:49 am

One (of many) useful additional pieces of information that would be nice to add to is a simple file or set of files containing the MMS location tab information, equipment tab, and the Obstructions / Exposure information for each USHCN station. I have begun collecting this information into a single Excel spreadsheet for each station I have visited. It is pretty easy to collect for an individual station (copy -> paste special -> paintbrush reformat), but collecting this for each USHCN station in the country via MMS is pretty tedious. I have not been able to figure out how to just dump it from the system with one query.
The reason I think it would be useful is that it provides an at-a-glance view of how many times a station has been moved, how often the equipment has been changed (and when), and what the reported obstructions are (which can then be verified and clarified through a site visit).
One piece of (thus far anecdotal) information I have found in the location tab is that an awful lot of sites are located at water or waste water treatment facilities. I have a vacation coming up and plan to visit as many sites as possible along my route (per certain constraints imposed upon me by my wife). In pre-researching the sites for precise location and getting pre-approval to photograph them, I found that fully one half are at such facilities. Google Earth images show that, while the general location of the facility may be rural in nature, the site itself consists of a number of buildings and an awful lot of concrete and asphalt.
If we had this location information gathered in one place it would be pretty easy to due numerous types of interesting characterization on the USHCN station sitings.
In fact, if anyone out there is interested in helping me collect this data – perhaps some poor soul that has been unable to survey a site but still wants to help gather data – then email me at:
station dot survey at yahoo dot com
I can send instructions on how to capture the data and get it into a consistent form, and coordinate with you which sites to gather this data from.

Jeff C
July 12, 2007 10:17 am

The MS Terra Server website ( has USGS aerial photos and Topo maps that are usually from at least 10 years in the past. Most of the California photos seem to from 1994. While they don’t have the resolution of the Google Earth photos, I’ve found them helpful in determining how a site has changed over the years.
Looks like the site hasn’t changed too much from 1994. The topo map shows the freeway there in 1979, but the purple color on the map indicates it’s a recent addition.

Jeff C
July 12, 2007 10:31 pm

I have been doing almost the exact same thing, scraping the data off MMS and re-compiling it in Excel. I’ve found it is the only way to get an accurate picture of the station moves. Using the location data, cross-refrencing it with the update info and then comparing that to the changes in obstructions makes a muddled picture become quite clear. The location descriptions I have found are often obsolete and don’t reflect the latest location.
Another observation is that the lat-long are usually quite accurate after around 1997-1998 when the NWS seems to have updated the info using GPS (at least for California stations). For station locations before that time period the lat-long can be way off and was apparently just a WAG. You get a feel for this by seeing how much the coordinates change after a fixed station is re-located using GPS (as noted in the updates tab). Locations can move as much as a half mile. It makes it very difficult to determine what exactly were the surroundings of the early stations that moved around if you don’t have a good location description.
I was going to discuss with our IT guys at work if there was a better way to pull the data from MMS as I was thinking about doing virtually the same thing you described. I’ll check into it and drop you an email at the address you listed.

July 12, 2007 11:45 pm

I’m going to try getting a flat data file from MMS. I have an idea.

Jeff C.
July 14, 2007 12:33 pm

I found a pretty good USHCN station history spreadsheet file when rooting around in the NCDC online archives ( Unfortunately, it ends about 1991 or so, but it has quite a bit of good information regarding early station histories. I’m still trying to decipher some of the columns as there are no headings or comments. If anyone finds a file with more recent info please comment here or let me know at jeffc1728 -at- yahoo -dot- com.

Leon Palmer
September 7, 2007 7:04 pm

I’ve added a 1994 doqq aerial image of the Paso Robles site at … Comparing it to the 2007 google images (and the close up images) there’s been a significant reduction in foilage (trees) since 1994. Anthropogenic Global Warming or Anthropogenic Landscape Beautification thanks to all the additional tax revenue from all the additional wineries?

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