Temperature Record In France Dominated By Urban Sites

By Paul Homewood

I was having a look at the GISS temperature record in France, and was astonished to find that there is only one rural station currently operational in the whole country. Moreover, this happens to be 4000 ft up Mont Aigoual.

I can hardly believe that a station up a mountain can give a representative climatic record for the rest of France.

http://data.giss.nasa.gov/gistemp/station_data/v3.temperature.inv.txt

The list above is of all the stations on the GHCN database, including ones not currently operational.The column at the far right is the Brightness Index, with 0-10 being regarded as “dark”, and therefore counted as rural. Also, the fifth column after the name gives the population in thousands – i.e Lille is 171000.

Of these stations, only thirteen are live:

Population

Thousands Lille 171 Brest 164 Strasbourg 252 Nantes 253 Bourges 75 Dijon 150 Limoges 136 Bordeaux 220 Mont Aigoual 0 Toulouse 371 Marseilles 901 Nice 331 Perpignan 101

Most are also airport sites, with the exception of Lille, Perpignan, and, of course, our mountain.

Ah, I hear you say, surely GISS will have adjusted for all of these urban influences? Well, let’s see how that worked out at Limoges.

This is the raw data from GHCN.

http://data.giss.nasa.gov/cgi-bin/gistemp/show_station.cgi?id=615074340000&dt=1&ds=12

And this is the version after GISS have supposedly adjusted it for UHI.

http://data.giss.nasa.gov/cgi-bin/gistemp/show_station.cgi?id=615074340000&dt=1&ds=14

So the GISS adjustment has actually made the past cooler, by 0.3C, up to 1981. Put the two together to see the full effect.

We find, therefore, that the temperature record for France is not only dominated by large urban sites, but that the UHI adjustment cannot even be trusted.

But it’s good enough for climate science!