Gary Archibald, Weathercaster

Do you ever wonder how exactly animals that live in polar climates – on either pole – are able to cope with, thrive actually, in subzero temperatures, wind-chills, snow and ice, blizzard conditions throughout the year? Conditions, by the way, that would kill a human being in minutes without the proper outerwear protection

This is the first in a series focusing on the fascinating animal kingdom and the dynamic world of weather and climate. First up, let’s examine our friend KNUT – the famous polar bear cub who was abandoned by his mother and is now taken in by the Berlin zoo to the delight of a throng of fans around the world. Knut’s accommodations are less polar arctic and tundra and more climate-controlled Holiday-Inn…at least for a bear. But for his relatives who roam the Far North, conditions are much harsher, and the weather plays a big part of that story. Picture temperatures in Nunavut Canada, where temperatures can approach –49 F or colder! How could any creature cope?

Knut, the polar bear cub, rolls in the sand during his first public appearance in the Berlin Zoo on Friday, March 23, 2007.

PHOTOS: Crazy For Knut

Mother Nature made Polar bears unique and ideally suited to such conditions. A polar bear's fur is white (individual hairs are transparent like the water droplets that make up a cloud) and provides good camouflage and insulation. It may yellow with age. The fur acts as miniature greenhouses, and turns sunlight into heat, which is absorbed by the bear's black skin. Stiff hairs on the pads of its paws provide insulation and traction on ice.

A sow polar bear rests with her cubs on the pack ice in the Beaufort Sea in northern Alaska.

Unlike other Arctic mammals, polar bears do not shed their coat for a darker shade in the summer. It was once conjectured that the hollow hairs of a polar bear coat acted as fiber-optic tubes to conduct light to its black skin, where it could be absorbed - a theory disproved by recent studies. The thick undercoat does, however, insulate the bears: they overheat at temperatures above 10 °C (50 °F), and are nearly invisible under infrared photography; only their breath and muzzles can be easily seen. When kept in captivity in warm, humid conditions, it is not unknown for the fur to turn a pale shade of green. This is due to algae growing in the guard hairs - in unusually warm conditions, the hollow tubes provide an excellent home for algae. Whilst the algae is harmless to the bears, it is often a worry to the zoos housing them, and affected animals are sometimes washed in a salt solution, or mild peroxide bleach to make the fur white again.

PHOTOS: Lords Of The Arctic

Up next, I’ll examine desert dry conditions and a certain desert dweller that finds cooler temperatures during the blazing heat of the day beneath the sand’s surface.

Thanks for dropping by!

GA