Sun Power [W/m2] Correlates to Warming [English Subs]

KRO Brandpunt, a actualities program, investigates the hot spring in Holland. They talk to Bert Heusinkveld, a meteorologist from Wageningen University.

Wageningen University has a long running program to measure the sun's activity. Over 90 years, the sun's power (in W/m2) in Holland has increased about 20%, while the temperature has increased 1,5ºC.

Correlations taken from the 2nd image:

Sun power (W/m2): y = 0,23x + 97,18 (R2=0,42)
Temperature (ºC): y = 0,016x + 8,816 (R2=0,298)

With x the number of years since 1928.

[editorial note]
Also the number of sun hours have increased, about 400+ on a yearly basis. In 2009, the MSM ran a story on the findings of Wageningen University, at that time it was claimed it was unknown why there were less clouds and why the sun power has increased.

One might think of increasing atmospheric humidity when the earth is heating up, but the opposite is true. Absolute and relative humidity in the atmosphere is dropping at most air pressures, except for the lowest levels of the atmosphere.