The stations were as far as possible
rural one's in three groups: East is in the modeled zone in Europe
(near the Finnish-Russian border) where the largest influence (4-6
ºC) should be seen in the period 1975-1990, when the anthropogenic
SO2 emissions more than halved (-56%) . Middle is the zone with a
medium influence (2-4 ºC at South Scandinavia/North Germany), and
West is Ireland/South England (0-2 ºC).
The stations choosen from the GISS database are:
East: Vytegra, Reboly, Kajaani, Jyvaskyla (average 62.9N, 30.2E)
Middle: Visby, Leba, Lindenberg, Oslo Gardermo (marked as rural!),
Schleswig-Jag (average 57.7N, 14.1E)
West: Lerwick, Shannon airport, Belmullet, Valentia obs. (average
As one can see, the largest difference in temperature in the middle and
east zone's is some 2 ºC, while in the west zone it still is
1 ºC. Far less than what the model calculated. Even if we
accept that the full difference in temperature is from less SO2
emissions, that means that the global influence is at maximum
0.1 ºC. But even that is questionable, as the NAO has a
distinct jump in 1990 to strong positive, the same year that the
temperatures in all three trends show a jump. The difference between
the west trend and the two other trends can be explained by the damping
influence from the oceans.
To make a comparison, here the NAO trend:
The influence of aerosols in current models is largely overestimated.
Consequently: to fit the past trends, especially the 1945-1975 period,
the models need to reduce the influence of GHGs on temperature. That
besides the point that they probably underestimate solar influences too.