When is it time to tell humanity of the planet's extinction? sharpen it. asked 46 sec ago - 4 day left to answer

I was kept up tonight by an article (below) about the predicted climate change for the next few years. It struck me enough to ask:

If you could calculate, precisely, that the whole planet- as a viable object capable of sustaining life- was coming to an end, would you tell anyone? Would you tell everyone?

If it was possible to prevent this, what would you be morally willing to resort to; how much power would you need to make it happen? Will the television and the internet collectively announce when it's time to pick up arms in concert to prevent the extermination of our race?

Is anyone else worried about this lack of stewardship, or is it just me?