Ozone loss in the Arctic or the North Pole. The Earth is covered by a blanket of ozone 12 miles (20 kilometers) above the surface which blocks most of the sun's high-frequency ultraviolet (UV) rays to protect people from sunburns and skin cancer.

Extremely cold temperatures in the North Pole coupled with chlorofluorocarbons (CFCs) have helped strip the Arctic atmosphere of most of its protective ozone to create what is called the first Arctic ozone hole. Unlike the South Pole where there is little human settlement, the North Pole ozone depletion can cause major problems for cities in the region as the low-ozone air drift southward.