Thousands gathered for the Climate Rally held at the National Mall in Washington DC, a free concert for the 40th anniversary of Earth Day. April 25, 2010. (Photo by Jeff Malet)

Hot Ideas for a Cooler Planet, is a public art project designed to raise awareness on solutions for global warming. In Washington DC, "Prairie Restoration" globe by artist Nina Weiss. April 22, 2010 marked the 40th Anniversary of Earth Day. (Photo by Jeff Malet)

Thousands gathered for the Climate Rally held at the National Mall in Washington DC, a free concert for the 40th anniversary of Earth Day. April 25, 2010. (Photo by Jeff Malet)

Characters of the environmentally themed movie Avatar join the thousands gathered for the Climate Rally held at the National Mall in Washington DC, a free concert for the 40th anniversary of Earth Day. April 25, 2010. (Photo by Jeff Malet)

Earth Day Rally To Save The Whales on the National Mall in Washington DC. April 22, 2010 marked the 40th Anniversary of Earth Day. (Photo by Jeff Malet)

Thousands gathered for the Climate Rally held at the National Mall in Washington DC, a free concert for the 40th anniversary of Earth Day. April 25, 2010. (Photo by Jeff Malet)

Characters of the environmentally themed movie Avatar join the thousands gathered for the Climate Rally held at the National Mall in Washington DC, a free concert for the 40th anniversary of Earth Day. April 25, 2010. (Photo by Jeff Malet)

CityDance dancers Kate Jordan and Kaitlin Madzelan. CityDance Ensemble performed their environmentally themed dance "Perigrine" on the National Mall in Washington DC during Earth Week Celebrations. Hot Ideas for a Cooler Planet, is a public art project designed to raise awareness on solutions for global warming. In Washington DC, "Clinton's Climate Initiative" globe by artist Sandra Bacon. April 18, 2010. (Photo by Jeff Malet)

Thousands gathered for the Climate Rally held at the National Mall in Washington DC, a free concert for the 40th anniversary of Earth Day. April 25, 2010. (Photo by Jeff Malet)

Hot Ideas for a Cooler Planet, is a public art project designed to raise awareness on solutions for global warming. In Washington DC, "Clinton Climate Initiative" globe by artist Sandra Bacon. (Photo by Jeff Malet)

Bolivian Folkloric Dance "La Diablada" performs on the National Mall in Washington DC during Earth Day Celebrations. April 18, 2010. (Photo by Jeff Malet)

Hot Ideas for a Cooler Planet, is a public art project designed to raise awareness on solutions for global warming. In Washington DC, "Clinton Climate Initiative" globe by artist Sandra Bacon. April 22, 2010 marked the 40th Anniversary of Earth Day. (Photo by Jeff Malet)

Thousands gathered for the Climate Rally held at the National Mall in Washington DC, a free concert for the 40th anniversary of Earth Day. April 25, 2010. (Photo by Jeff Malet)

Taking a spin on the Carousel during Earth Week on the National Mall in Washington DC on April 17, 2010. (Photo by Jeff Malet)

Kids have their face painted in the Return to Pandora Tent during Earth Day celebrations on the National Mall. Pandora was the local of the environmentally themed movie Avatar. April 22, 2010 marked the 40th Anniversary of Earth Day. (Photo by Jeff Malet)

Hot Ideas for a Cooler Planet, is a public art project designed to raise awareness on solutions for global warming. In Washington DC on April 18, 2010 on the National Mall in Washington DC during Earth Week. (Photo by Jeff Malet)

The Washington School of Ballet performs on the National Mall in Washington DC during Earth Day Celebrations. April 18, 2010. (Photo by Jeff Malet)

Hot Ideas for a Cooler Planet, is a public art project designed to raise awareness on solutions for global warming. In Washington DC, "Wind Power" globe by artist Karen Ami. April 18, 2010 on the National Mall in Washington DC during Earth Week. (Photo by Jeff Malet)

The giant panda is the rarest member of the bear family and among the world's most threatened animals - and the mascot of the World Wildlife Fund. Earth Day Celebrations on the National Mall on April 18, 2010. (Photo by Jeff Malet)

U.S. Sec. of Education Arne Duncan meets with Maya Willey of the No Child Left Inside Nature Club of Hillsmere Elementary School of Annapolis, MD. Maya shows him an eel. On the National Mall in Washington DC. April 22, 2010 marked the 40th Anniversary of Earth Day. (Photo by Jeff Malet)

Denis Hayes, the founder of Earth Day speaks to the thousands gathered for the Climate Rally held at the National Mall in Washington DC, a free concert for the 40th anniversary of Earth Day. April 25, 2010. (Photo by Jeff Malet)

NASA's Dr. Thomas Wagner gave a presentation entitled “State of the Science” which featured the latest observations on shrinking arctic sea ice and the rapidly-changing Greenland and Antarctic ice sheets. Earth Week on the National Mall in Washington DC. on April 17, 2010. (Photo by Jeff Malet)

NASA's Dr. Thomas Wagner gave a presentation entitled “State of the Science” which featured the latest observations on shrinking arctic sea ice and the rapidly-changing Greenland and Antarctic ice sheets. Earth Week on the National Mall in Washington DC. on April 17, 2010. (Photo by Jeff Malet)

Director Robert Stone produced Earth Days, a feature documentary that recounts the history of the modern environmental movement from its beginnings nearly four decades ago. It recently appeared on PBS. He was at Earth Week on the National Mall in Washington DC. on April 17, 2010. (Photo by Jeff Malet)

James Cameron, the producer of the environmentally themed movie Avatar join the thousands gathered for the Climate Rally held at the National Mall in Washington DC, a free concert for the 40th anniversary of Earth Day. April 25, 2010. (Photo by Jeff Malet)

U.S. Secretary of the Interior Ken Salazar speaks during Earth Day festivities on the National Mall in Washington DC. April 22, 2010 marked the 40th Anniversary of Earth Day. (Photo by Jeff Malet)

Rep. Ed Markey (D-MA) speaks to the thousands gathered for the Climate Rally held at the National Mall in Washington DC, a free concert for the 40th anniversary of Earth Day. April 25, 2010. (Photo by Jeff Malet)