The charts above, from The New York Times, show the effects of global climate change that will cause rising sea levels. On the left is the projection we have heard about. On the right is the new and more accurate projection due to new research.
It turns out that rising sea levels will be much worse than expected by 2050. It will affect three times as many people as previously thought. About 150 million people live in areas that will be under water at high tide in 2050. All of those people will need to relocate well before 2050.
And this is just the damage that is irreversible -- that the current climate change will cause even if we take action now to curb global climate change. And the areas in the pictures above are not the only ones that will be affected. They are just some of the worst. There will also be many other places -- including places in the United States.
It could get even worse, since the world (and the U.S.) has not yet taken sufficient action to limit global climate change. How bad do we want to let it get?
NOTE -- This is only about rising sea levels, but there are many other disastrous effects of global climate change (drought, floods, fires, more dangerous tornados/hurricanes, etc.). Denial will not fix this, and waiting will only make it worse.