Global warming is real, and it started about 15,000 years ago. Otherwise we'd still in an ice age.
Since then sea levels have risen about 400-430 feet.
A little more warming won't be too much of a problem. It would actually help most of the industrialized northern hemisphere.
Global cooling or another ice age would be a
real problem. Imagine 2-3 miles of ice stacked up all along the Canadian border and the northern US, with all of the climate zones shifted proportionately south. As in
way south!
Given the current status of the climate research, we can't be sure which way we're headed. The research has been hijacked by zealots out to confirm their chosen beliefs, as these recent hacks have shown.
When we're betting trillions of dollars we really do need accurate data. And we need fewer zealots masquerading as scientists.
Religious belief does not constitute scientific evidence, nor does it convey scientific knowledge.