World in Our Hands

1600 × 1048

Hourglass with City and Ice

1534 × 1293

Earth Day 2012 celebration

1600 × 900

Pollution and environmental crisis

1280 × 1024

Pollution and environmental hazards

1280 × 1024

Polar Bear in Alley — Gray, Dramatic, Photograph

2560 × 1600

Nuclear Power Plant Cooling Towers — Gray

1200 × 960

Penguins in a polluted alley

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Polar bear in urban alley

1024 × 768

Penguins in a polluted alley

1200 × 827

Polar Bear in Alley — Gray, Dramatic

1024 × 768

Earth on fire

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