Earth's temperature has increased during the past decade, changing the physical state of a portion of Earth's water and producing some very dramatic, powerful, and deadly weather patterns. Research some aspect of global warming as it applies to a specific change of state of water.
OR- check out Will Steger's website on his upcoming exploration to prove that global warming does in fact exist. Read the adventure that Steger is about to begin and write a short paper about the travels he is about to begin and what he hopes to prove on this expedition.
www.willsteger.com