This is an interesting account of the possibilities of regeneration of environmentally greener earth once the humans are wiped out instantly. Overall, the article, citing optimistic facts, seems to provide enough reasons for us to abandon the earth and let it regrow to its natural condition. It argues that, provided enough time, the earth will eventually get back to its natural condition with no obvious signs of the presence of a previous intelligent life on it.
I think that the article is compelling, but, haven’t they done a (practically) fruitless exercise? We know pretty for sure that no one is going to leave earth sooner and even if we are wiped out by a cataclysm, who would be here to confirm these facts.