Well this should be easy. All you have to do is prove that global warming is real and caused by human activity.
Ah, you do have to use science though: but that shouldn't be a problem given the "consensus" and all that.
Can't wait to see the first entry. Any entry come to that. Problem with global warming is the same for all ecomyths: asserting it's so, doesn't make it so.
A lie is a lie: doesn't matter how often or how loudly it is repeated. Saying it is, doesn't mean it is -- especially in science.
No use getting upset with me: write out your proof, send it in and collect $100,000: much more productive and creative. But again, that's another thing about critics -- they don't actually create anything of value.
Side bet: more people criticise the contest (and/or its sponsors) than actually submit entries.