[pale-hands]

Global average temperatures 6000 years ago were 0.5 °C warmer than baseline (1961-1990 average), now it's 1.1 °C. Historical warm periods were local, and global average temps did not exceed current temperatures. (Also, modern is a weasel word here -- you could pick e.g. 1920 and be correct).

Even if warming stopped now, Arctic and Antarctic would continue to melt for decades to come. Rate of change is key.

Your reference is also local (to the arctic), not global.

Again, what argument are you making here?

Is it: 1: It was warmer in the past / 1a: but nothing bad happened / 1b: therefore current warming is not due to human activity / 2: therefore there is no need to reduce CO2 levels.