One of the most surprising things I’ve learned from the surfacestations.org project is that for some odd reason, there are a number of climate monitoring stations of record in the USA at sewage treatment plants. If you’ve ever driven by one of these in the wintertime, they tend to look like steam saunas. They are localized heat bubbles from the waste-water processing.
At Orangeburg, SC not only is the official USHCN climate station of record at a sewage treatment plant, it’s also a nonstandard thermometer (a climate station normally looks like this), and strapped to the side of a telephone pole. I don’t know about you, but experience with creosote treated telephone poles tells me that they’d tend to create a hotter local measurement environment.
Then there’s the brick building to radiate heat at night, the asphalt parking lot, the effluent channel running nearby, and the overall sewage treatment plant waste heat to consider. I doubt there is an easily applicable set of equations which can untangle the myriad of potential microsite biases.
Then there’s sewage. As population growth occurs, sewage plants add more vats and equipment to handle the increased volume. The increased volume of effluent loses some of it’s heat at this location during the purification process.
Click graph for larger version, data from NASA GISS
The real question is: What are we actually measuring at this location? Are we measuring temperature as an indicator of climate change or are we measuring waste heat from increases in sewage processing that mirrors local population growth?
UPDATE and CORRECTION:
I made an error, this is not a sewage treatment plant. It does treat water, and the description in the site survey from the surveyor was “water filtration plant” which I mistook to mean “sewage treatment” since so many other locations have been at sewage treatment facilities. For example, one of the worst is Titusville, FL, which has been highlighted in this blog in Part 31 and also surveyed by the same volunteer. I looked at the photos he provided, and did not discern initially that the tanks were not for sewage treatment. Some sharp eyed readers have pointed out the identification problem, which I’m happy to correct.
The questions about the validity of the temperature measurement environment in the midst of a sewage treatment plant are still valid, but do not apply to this location. So the question we now have for this location is; do the large water filtration pools on this site provide an evaporative cooling effect or do they release heat?
The water vapor impacts at the facility are likely a factor, possibly for Tmin overnight, which is more prone to such effects. Note that there has been new construction at this location, and given the apparently new water filtration pools added on site, there may still be an effect of measuring the local population increases by proxy.