Reference link:

http://en.wikipedia.org/wiki/Global_warming

http://www.ncdc.noaa.gov/oa/climate/globalwarming.html

http://earthobservatory.nasa.gov/Library/GlobalWarmingUpdate/

http://www.conservapedia.com/Global_warming

http://environment.about.com/od/faqglobalwarming/f/globalwarming.htm

http://en.wikipedia.org/wiki/Effects_of_global_warming

http://www.global-warming-and-the-climate.com/

http://www.nrdc.org/globalWarming/f101.asp

http://www.environmentalgraffiti.com/sciencetech/5-deadliest-effects-of-global-warming/