The way it happens is that sea level rises slowly, so slowly it's barely noticeable. Then, literally overnight, a storm causes specific sections of land to go underwater. It's very expensive, even if we plan for it. But we never do seem to plan for it adequately, do we?
CO2 emissions will go down as fossil fuels become harder to obtain and the cost of alternative energy decreases. It's inevitable to reduce CO2 emissions, because fossil fuels will simply be exhausted. All we can do is speed up that process by imposing a carbon tax. We came together to reduce CFC emissions and sulfur emissions to alleviate the ozone hold and acid rain, so why not CO2 emisisons?
Maybe the press reports on the people who are more famous (who tend not to be AI researchers). But Stuart Russell, UC Berkeley AI researcher and co-author of the best selling AI textbook of the last two decades, has concerns about the matter, too.
In any case, when you're close to the project you can tend to lose sight of the big picture. Probably few scientists at Los Alamos thought of the long-term consequences of the weapons they were designing.
Another thing to keep in mind is that hardly anyone believes that we're close to creating human-level artificial intelligence, particularly AI researchers.
It has just been discovered that research causes cancer in rats.