History and science shows climate change has to do with our earth not being exactly round, and our magnetic poles shifting. Look it up !
It has happened many times , lush green areas become 🏜️ or frozen tundras, and vice versa, I guess that's why I find seashells 5000ft up in the mountains.

And what's the problem with them waiting ? Or border control ? It's our country and just like your home, do you leave your doors open 24/7 whether or not your home. Of course you don't, because you don't want just anyone in your house because there's bad people out there, and you need to sort through them before letting them in, especially around your family and loved ones.
It's the same thing with our borders we just don't want bad people coming in hurting those we love and want to protect, maybe a good solution would be to spend more money on our border infrastructure, making it faster to process those coming to America, than sending money to aid other countries when we ourselves need it.