Highlights of the global climate's decade:
2001 - U.S. President George W. Bush publicly rejects the 1997 Kyoto Protocol to rein in greenhouse gases.
2005 - After Russia's ratification, the Kyoto Protocol takes effect for 37 industrialized nations.
2005 - The year's average global temperatures are the highest in recorded history, NASA reports.
2007 - The summer melt of Arctic sea ice is the greatest on record, the U.S. National Snow and Ice Data Center reports.
2007 - In its first assessment in six years, the U.N. scientific panel on climate projects temperatures may rise as much as 11.5 degrees Fahrenheit (6.4 degrees C) in the 21st century if nothing is done.
2009 - Focus falls on December's U.N. climate conference in Copenhagen as the arena for a new global agreement to combat warming.
