In a little over a year into the www.surfacestation.org project, volunteers have surveyed about 600 stations now, roughly half of the 1221 USHCN climate network. One of the things I had hoped for would be finding more CRN1 and CRN2 rated stations as the Midwest has been surveyed. Unfortunately, that doesn’t seem to be happening, and the number of CRN1/2 stations just isn’t climbing much.
I’m about to publish a significant update to the surfacestations rating, I’m way behind in that work, but have been monitoring new stations, so look for that soon.
Last week I had an inquiry from Frank Perdicaro about a weather station in Los Angeles County, Cogswell reservoir, that looked like it had the potential to be a really well sited station. Situated in the mountains east of the LA basin, it was “miles from everything”, about 6 miles NE of the Mount Wilson observatory, and the road to it was closed to vehicle traffic. It also had a long record. It is a station operated by the Los Angeles Water District, which manages the reservoir.
To see it, you had to hike or bike to get there, because 9/11 closed access to a lot of reservoirs, such as Fairmont, which is a USHCN station that I previously surveyed, but could only do it from aerial photos. I wanted to see what Cogswell looked like, so I put out a call for help on this blog to get it surveyed. Readers Jason Salit and Hyon Min responded, and after discussion as to who was best suited for the job, Hyon hiked up last Sunday to survey the station.
First let us look at where the station is situated on Google Earth:
Cogswell Reservoir is the yellow marker – click for larger image
From a map and satellite image perspective, the station looks quite remote, being in the rugged mountains of the Los Angeles National Forest:
Click for larger image
Google Earth live link is here
But thanks to Hyon, we get a completely different view from the ground:
Click for larger image – note the old style Stevenson Screen with wooden legs.
I really want to thank Hyon for making the hike in, that was above and beyond.
While quite remote, and well removed from Los Angeles’ UHI signature, disappointingly, the Cogswell Reservoir Station is just a few feet from an asphalt driveway and exists in the sole island of human habitation for miles, the office that manages the reservoir and the forest area. The data quality curse that is the requirement for an observer to walk to the station and take a manual measurement strikes again. What could have been a CRN1 or 2 station ended up being a CRN4 due to proximity to asphalt and shading issues.
See more pictures here
Add to that the shade trees, the nearby reservoir level changes, and the changes in nearby infrastructure such as the driveway, who knows what the real climate signal from such a station might be? In fairness I should point out that the primary mission of this station is precipitation monitoring for the LA Water District, but stations like this one, one found by researchers to be away from UHI and having a long unblemished record, often end up as prime candidates for climate science studies. Yet few researchers do any due diligence beyond looking at the data.
There’s a station at the Mt. Heber Ranger Station in the far northeastern part of the state that found it’s way into a study, so did one at the Nevada City Water Treatment plant, and neither are USHCN stations. More on those another day.
Today I had an outing with my wife and children, the first in weeks due to smoke from wildfires. We decided to go to Redding’s Turtle Bay Museum, arboretum and nature center. Thinking I’d get a break from thinking about weather stations for awhile, I found myself assaulted with this right next to the butterfly exhibit:
The sign says “Mosquito Meteorology”. Curious, I read it only to discover that this is station used to monitor weather conditions for the local Mosquito Control District. They placed it at the Turtle Bay nature center so that it could be used as a “teaching tool”.
Great. Let’s teach the kids about measuring weather and how temperature affects the mosquito vector and breeding cycle. Only one problem, this station has a lot of potential biases.
Note the galvanized sheet metal used to prevent kids from climbing the tower. It was hot to the touch in the midday sun and only a few inches from the temperature and humidity sensor. There’s quite a bit of surface area there on that metal sheet. Note also the black mold in the Gill shield for the temperature and humidity sensor. Then we have the trees, fast growing “Digger pines” that enclose the space around the station which exists now ina clearing just outside the nature center. They probably weren’t an issue 15 years ago. But now they bias not only the temperature sensor, but also the wind sensors, and the rainfall record, all of which are important to the science of mosquito vector control.
I wonder how long it has been since the mosquito control folks have visited this station to see it’s condition? What have we learned here kids? Out of sight, out of mind, as long as it produces data, don’t worry.
Ok, the drive home I had another “weather station assault” when our drive down Highway 99 took us past the Wilson Landing Fire Station. Out of the corner of my eye I got a glimpse of a Stevenson Screen, which surprised me, since I “thought” this COOP station had been closed years ago when NOAA closed the Redding NWS forecast office. This is at Butte County Fire Station #41 at 13871 State Highway 99 near the town of Nord.
Doing a U-turn I went in to investigate. I found the station still in operation:
Click for a larger image
More photos here
It was used by the Redding NWS office for forecast performance checks, mainly for rainfall. I know this because a similar station operated by Redding WSFO was a few miles down the road at my own TV and radio station, which was also discontinued when Redding WSFO closed.
The station now serves the California Department of Forestry fire division with weather info, even though it is just a few feet from a building, asphalt and dumpster.
The paint and roof of the station Stevenson Screen is also in really bad shape:
It is nice to see that they place equal importance on weather data with the trash. I can just imagine the dialog at the fire station:
Take out the trash! …and while you are at it, read the weather station and write it down in the logbook!
As I said, it is getting harder to find well sited weather stations these days. Such scenes as demonstrated above are the norm, not the exception.