| Many arctic pinnipeds migrate with the movement of food, but also with the seasonal movement of the ice pack. |
| At temperatures below minus 5 degrees Celsius in heavy snow, small debris and snow can pack around the warm saw motor and form a solid ice pack. |
| Prowling the ice pack, a polar bear hunts for seals during summer's thaw, or take advantage of the open water to seek food. |
| Not all of them know, however, that if it's left there too long, or applied directly to the skin, an ice pack can cause serious frostbite. |
| Over the past 40 years, the Arctic ice pack has thinned and shrunk significantly. |
| They were going to drill down into the ice pack and measure the accretion of ice year by year. |
