Albedo effect

The albedo effect on sea. Illustration: Norwegian Polar Institute

The albedo effect on land. Illustration: Norwegian Polar Institute

Albedo describes the ability of surfaces to reflect sunlight. Light-coloured surfaces immediately return a large part of the solar energy back to the atmosphere (high albedo). Dark surfaces absorb the energy from the sun and convert it to heat (low albedo). The Albedo Effect is a self-reinforcing effect which is important for the development of climate change globally, including the melting rate of the ice and the temperature of the oceans.

Ice- and snow-covered areas have high albedo, and the ice-covered polar regions reflect solar radiation which otherwise would be absorbed by oceans and land areas and cause the Earth’s surface to heat up. The proportion of the Earth’s surface that is covered by snow and ice has a great deal to say for how much of the incoming solar radiation is reflected or absorbed. Low albedo (dark surfaces) leads to higher uptake of energy and, hence, warming. Moreover, when more ice and snow melt, there will be more dark surfaces and increased warming. This is therefore a self-reinforcing effect. Climate change in the Arctic and the Antarctic isconsequently important for the development of global climate change.