Although indeed the temperatures and GHG have been lower and higher on Earth before, that was never with the amount of humans we have now. Our economy and socie

Although indeed the temperatures and GHG have been lower and higher on Earth before, that was never with the amount of humans we have now. Our economy and society is quite optimised and our infrastructure hubs are largely located on coasts. Our prosperity also relies on a large amount of sophisticated technology that is hard to replace and to bootstrap. So although the human species will probably survive a drastic climate change, many individuals will not due to famine, lack of medical supplies and care, and war over the remaining resources.