Alright I am constantly reading both sides of this argument, and the majority of scientific data supports that humans are contributing to global warming, not causing it.
The earth has a history of warming and cooling, for example in the 1200s there was a little ice age that was caused by volcanic eruptions.
However the average world temperature has increased significantly more rapidly then in the past starting in the late 19th and early 20th century.
Read:
http://oceanworld.tamu.edu/resources/oceanography-book/evidenceforwarming.htm
http://www.today.ucla.edu/portal/ut/climate-change-is-here-to-stay-168333.aspx
http://math.ucr.edu/home/baez/temperature/
http://www2.ucar.edu/climate/faq
environment.yale.edu/climate/files/ClimateChangeKnowledge2010.pdf
wserver.crc.losrios.edu/~larsenl/ExtraCredit/predictions-of-gmt.pdf
http://www2.sunysuffolk.edu/mandias/global_warming/global_cooling.html
I would like to point out that all the data i have presented is from professors or people in the field who work with this type of data. Most critics of global warming point to a period between 1998 and 2000 where the average temperature of the world dropped. However data will show you that while the average temperature will fall and rise, the long term average is still increasing dramatically.
And Al Gore is by no means the inventor of global warming, people who think that are retarded.
And even if global warming does end up reversing and the world begins to cool, is it worth risking the future of our sport by ignoring it?
Global warming is real, there is no doubt, the question raised is, is it man made? It is not man made, but we contribute to it.