By Paul Homewood
However, as I am accused of not showing adjustments that produce a cooling trend, I can report that I have actually found a couple; Jujuy in Argentina and this one in the town of Arica, Chile! Take a good look at it. These adjustments seem to be like Sheffield buses – you wait ages for one to come along, then have to wait even longer for the next one! (There is also the odd case of San Luis where GHCN have adjusted the 1940 temperature up, but also adjusted the 1939 down, effectively cancelling out – temperatures have also been adjusted downwards from 1945 to 1973).
Don’t get too excited though, because it appears GISS have forgotten to make their homogeneity adjustment for UHI for them, despite the fact they have populations of 124000 and 88000 respectively.(More on this later).
As usual, I have gone back to 1940 to compare the unadjusted and adjusted temperatures. (Temperatures for 2010 are the same in both versions). Appendix A shows the results for all GHCN stations with records back to 1940. Out of 37 stations, 14 have past temperatures adjusted down, 20 remain unaltered and only 3 are adjusted up, giving, as a crude average, an artificial warming trend of 0.27C. Add this to the adjustments in the Arctic and Australia of 0.70C and 0.30C respectively and a pattern seems to be building up.
Finally, I have listed populations and indicated which are airport sites. As you can see, there are only four rural sites, i.e. less than 10,000, and two of these are based at airports. Do these stations show a different trend to the rest and have the urban sites been adequately adjusted for their UHI effect? We’ll take a closer look at this tomorrow.
|Mar del Plata||407||13.46||13.36||-0.10|
For the sake of completeness, I have added to the original list a few stations which don’t have complete records back to 1940.