I’ve covered California’s temperature stations and their exposure problems extensively, now it’s time to head north to Alaska. When you think of Alaska, you think of cold, snowy, pristine remote wilderness, right? Surely there are no worries about urbanization affecting thermometers in the great white north. Well as I’ve said before, the NOAA MMTS system used to measure temperature for climate has two fatal flaws that keep it close to human influences: 1) a need for a person to read the display and write it down 2) A cable from the display to the sensor.
So it’s no surprise to find that in Cordova, AK the official NOAA thermometer (COOP Number 502173 60.55611°N -145.75306°W) is right next to the diesel power facility and it’s outdoor transformer. The display is inside where it’s warm and can be comfortably read.
Click for larger image – picture: John Papineau, National Weather Service, Anchorage AK
It’s not just the waste heat from power transformers nearby that can cause a bias, there’s also an air exhaust vent, and inside the building, which is known as the Orca Diesel Generation Plant is a very large diesel generator capable of providing 7 megawatts of electric power for the town of Cordova. Below is a view inside the facility from the Cordova Electric COOP web page.
It would seem a warmer than normal place, and you can see an aerial view of the power generation facility here from Google Earth. You can also see the aerial view, the thermomter is located at the blue building to the left of the storage tanks in the foreground (click for larger images).
Aerial view of Cordova, Alaska – click for larger images
Of course, a temperature sensor with that sort of proximity would be measuring waste heat from electric power generation in addition to normal climate fluctuations. Below is the GISS temperature plot for this station. Note the discontinuity around 1940 due to a station move, but also notice the positive step change that begins around 1980, likely a result of the well known 1976-77 PDO (Pacific Decadal Oscillation) shift.
I wonder if power demand in Cordova has gone up in the last 20 years? The Cordova Electric Company was formed in 1978 by a town vote and this facility was completed in 1984.
One of the things that NASA GISS and other research institutions claim is that we’ve had a greater rate of warming near the higher latitudes, as seen in the map below.
Map from NASA GISS
One has to wonder though, just how much of that has to do with temperature measurements being taken in proximity to a growing human population at these locations? More on the Alaskan temperature story to follow.