3. What will happen to sea levels if the climate warms 2 degrees?
Sea levels will certainly continue to rise if the climate warms 2 degrees Celsius (3.6 Fahrenheit). Sea level rise will not stop, even if the warming ends at 2 degrees. Instead, it will continue for many centuries due to the lag in response times of the world's oceans and massive ice sheets.
If we look at the distant past, 120,000 years ago, when only very early humans existed, the temperature was 2 degrees warmer than it is now. Sea levels were about 5 meters (16 feet) higher than they are today. Nearly 500 million people worldwide currently live below 5 meters elevation.