The Polar Bear Song

It's not only the polar bears who are confused by some of the science behind global warming. Here is a quick guide to some of the terms used in the song.

Ursus Maritimus

Latin for maritime bear. Although most polar bears are born on land, most of their time is spent at sea, hence its name meaning 'maritime bear'. They can hunt consistently only from sea ice, spending much of the year on the frozen sea. Polar bears feed almost entirely on seals. The seals come up out of the water into the breathing holes that are formed in the ice and it is there that the polar bears are able to capture the seals. Without ice, a polar bear is not able to capture a seal.

Milankovitch cycles

Astronomer Milutin Milankovitch developed the mathematical formulas upon which these orbital variations are based. He hypothesized that when some parts of the cyclic variations are combined and occur at the same time, they are responsible for major changes to the earth's climate (even ice ages). Milankovitch estimated climatic fluctuations over the last 450,000 years and described cold and warm periods. Though he did his work in the first half of the 20th century, Milankovich's results weren't proven until the 1970s.

CO2

Carbon dioxide: a colourless, odourless, non-poisonous gas that is a normal part of the air. It is absorbed by plants and exhaled by humans and animals. Burning fossil fuels (coal, oil, wood) increases carbon dioxide. Carbon dioxide is a greenhouse gas that contributes to global warming.

Northern Lights

The true name for the 'Northern Lights' is the Aurora Borealis. They are quite common high up in the atmosphere but they are, for most parts of the Earth, too far away and too faint to be seen. Sometimes, although it's very rare, you can see them in Scotland. The colours are amazing, lots of reds and greens - a bit like looking at a painting in the sky.