The first winter in North America was in the mid-20th century, a time when the North American Arctic was under ice and snow cover.
But the harshness of the environment was not yet understood.
Today, the cold and harsh conditions are a fact of life.
As Arctic temperatures rise and polar bears hibernate in deep snow, this is becoming an issue.
We’ll be watching for the first time in years as polar bears make their way into the Arctic, and will be watching closely for how the climate affects this iconic species.
For more about climate change and the Arctic and polar bear, visit Climate.gov.