Be fair, "the greatest climate disaster" started long before Trump took office. It might even be before Lincoln. It's just that nobody noticed it at the time, because it's taken a long time to build. Trump may, however, be president at a point of inflection (a point, because you can't even roughly model it with simple quadratic function). Things are, indeed, likely to get worse quickly for a bit, but Trump didn't cause that, he's just been refusing to ameliorate it.