From their site.
...For this assignment, we challenge you to capture climate change in all its aspects: impacts, examples, causes, means to fight it...
...Best shots of climate change effects will win $300 (first place), $200 (second place) and $100 (the third place) + our branded t-shirt...
...Sell the image rights (25$ per image)...
Why don't they just ask to bring an image from another planet for a friendly smile and a high-five?