As I've long suspected...
"Schiaparelli... discovered a correlation between precipitation, cloud cover and lunar phases on the synodic month... clear days were more frequent one week after new moon, and less frequent one week after full moon" (ie 3rd quarter to New Moon).
And confirmed by others in the 1960's...
http://books.google.com/books?id=vpV...esult&resnum=2
Now if only we could find a way to tow the moon away. Park it in front of the sun to shade the earth, should do nicely for a little global cooling.