I'm not worried about what happened in the past but I do understand that climate changes over geologic time. 2000 years ago it may have been warmer but where did the ice come from then? We didn't have US Naval Bases along the current coast line of the USA 2000 years ago. So back then and many thousand years ago the cold/warm cycles of the earth didn't bother mankind like it will today. The US Navy is very concerned about the opening in the North Atlantic where Russian Subs can now travel in the summer months as the North Seas have much less ice over them these days. And if the ocean levels rise it will threaten our ocean side naval bases. It will also threaten people living along the coast lines. I'm fine in that I'm way above current sea level and won't be effected directly.
One a side note it was over 60 deg F the ohter day and before that it was cold as H. The temperature variations in Feb are abnormal don't you think? And the ice in the Antartic is melting faster now. They (explorers) found a big hole under he ice down there showing that the ice under the glacier has melted.
https://www.nbcnews.com/mach/science...ays-ncna967306
here is the same thing from NBC.