New research and like all good research poses more questions than it answers. And the caveat is that the 3 year period of the research may not be very significant in the rythms of the sun. But it only emphasises to me that climate models which ignore the sun are not really worth very much. And climate models will only begin to become interesting when the sun’s influences and mechanisms by which they apply are far better understood.
From The Telegraph:
An increase in solar activity from the Sun actually cools the Earth, suggests new research that will renew the debate over the science behind climate change.
Stronger Sun actually cools the Earth??
Focused on a three-year snapshot of time between 2004 and 2007, as solar activity waned at the end of one of the Sun’s 11-year cycles, the new data shows the amount of light and heat reaching the Earth rose rather than fell. Its impact on melting polar ice caps, and drying up rivers could therefore have been exaggerated by conventional climate models during the period.
Scientists also believe it may also be possible that during the next upturn of the cycle, when solar activity increases, there might be a cooling effect at the Earth’s surface.
In the New Scientist:
Joanna Haigh of Imperial College London studied satellite measurements of solar radiation between 2004 and 2007, when overall solar activity was in decline.
Haigh’s measurements showed that visible radiation increased between 2004 and 2007, when it was expected to decrease, and ultraviolet radiation dropped four times as much as predicted. Haigh then plugged her data into an atmospheric model to calculate how the patterns affected energy filtering through the atmosphere. Previous studies have shown that Earth is normally cooler during solar minima.Yet the model suggested that more solar energy reached the planet’s surface during the period, warming it by about 0.05 °C.
An influence of solar spectral variations on radiative forcing of climate
by Joanna D. Haigh, Ann R. Winning, Ralf Toumi & Jerald W. Harder
(Nature, DOI: 10.1038/nature09426).
The effect is slight, but it could call into question our understanding of the sun’s subtle effects on climate. Or could it? Stefan Brönnimann of the University of Bern in Switzerland says Haigh’s study shows the importance of looking at radiation changes in detail but cautions that her the results could be a one-off. He points out that the sun’s most recent cycle is known to have been atypical
The k2p blog 