250 years ago the glaciers were growing.
Please recognize as well, glacier growth is not just a function of being very cold. Glaciers can grow BECAUSE it warmed up.
When it is very cold, the air contains little moisture. Glacier grow depends on enough snowfall. Warming up from 10°F to 25°F can often result in more snowfall.
Sea Ice is a better indication of temperature than glaciers.
Right. So when they began to shrink, was it caused by man?