Sources

http://www.enchantedlearning.com/subjects/astronomy/planets/earth/Seasons.shtml

http://en.m.wikipedia.org/wiki/Sunlight

www.cossweb.com/weatherandwater

http://www.bgs.ac.uk/discoveringGeology/climateChange/general/causes.html?src=topNav

http://mail.colonial.net/~hkaiter/Seasons.html