because if it happens at a slower rate we can better prepair for it. at the rate its warming now we are SOL, millions and millions will die from the heat; you can see examples on a smaller scale of that every summer from people dying from the heat. take a look at what happened in europe a few years ago when they had that huge heat wave, i think it was something like 3000 died or maybe it was 1500 i cant remember. and what is going to happen when it gets hot people are going to be constantly running their A/C’s to stay cool putting even more co2 emisions in the air, we are just going to bake ourselves to death.
not only that costal lanscapes are going to change drastically from the 20+feet rise in sea level putting many cities under water. not only will costal landscapes change but you will see deserts turn from sand to grassy land and vice versa. u can see this starting to happen on parts of india