oh heck here's it's response to the Venus part:
"Climate scientists and astrophysicists have looked into this extensively. The definitive scientific consensus is that a Venus scenario is physically impossible on Earth from burning fossil fuels. To trigger a runaway greenhouse effect that vaporizes the oceans (like Venus), Earth would need to receive much more solar radiation than it currently does. Even if we burned every single ounce of fossil fuel on the planet and triggered all feedback loops, the Earth would become devastatingly hot and hostile to human civilization, but it would eventually stabilize. It would not turn into Venus."