This is a preliminary post to a much more detailed one coming from my friend Paolo Mezzasalma. who is doing a tour of Italy’s weather stations.
While there are significant and systemic problems with USHCN stations in the United States, there are also problems with stations worldwide. One of the problems is that a good percentage of GHCN stations are at airports. For example, Paolo sent along a photo of the weather station at the Ciampino Airport in Rome, Italy. It piqued my interest for obvious reasons.
The arrows point to three different weather stations. two are Stevenson screens, the third is an automated “ASOS” like weather station presumably used for aviation weather. Note the proximity to the parked jets and tarmac.
“You see two Stevenson screens: the official one to the East and an automatic Data Collection Platform to the West, which was added recently.”
But that’s not all, this weather station site has other heat islands nearby, like a nice semi truck parking lot. That’s always good for a warm boost.
In fact this weather station is caught between two modes of transportation. Trucking and aviation. I wonder which affects it more? I wonder if the jet parking area and the trucking staging area were always there?
Note also the red/white striped light pole missing in the older photo at top, but present in the annotated photo. You can view that photo interactively here. The jet on the right is also missing. The differences in photos underscores the fact that airports are hardly static places, and expansions, improvements, and construction is the modus operandi at most airports today.
Here’s the view looking south.
Here is the interactive view
I wonder how the jet blast affects the high temperature recorded at the airport weather station on certain days when they take it out for a spin? I wonder how much the tarmac adds, or the trucking parking lot adds? Or is it all swamped by Rome’s UHI?
UPDATE: for those that might question whether jet exhaust could reach the weather stations, this instructional video from United Airlines done at the San Francisco airport in 1993 might be helpful in visualizing the problem. (h/t to “Just want truth”)
The TV show Mythbusters also recently did a similar demonstration.
So what are we really measuring at those weather stations at Rome’s airport?
The ENVIBASE project reports:
In the [Rome] urban area, five meteorological stations continuously collect climatic data, such as temperature, relative humidity, wind velocity and orientation, rainfall intensity, atmospheric pressure, etc., and organised them in a database form.
Such stations are:
* Urbe Airport;
* Ciampino Airport;
* Rome-Eur (operating for the last three years);
* Collegio Romano (located in the historic centre of Rome and collecting data since 1782);
* Monte Mario (for a limited period of forty years).
So what we have at Rome’s Ciampino airport is in fact a climate station. I’ll have more on this and other weather stations in Italy soon.