Albedo Definition

by Laurent Cousineau
(Montreal)

Albedo is the amount of solar radiation reflected from an object or surface, usually expressed as a percentage.

In the context of climate change, albedo is the fraction of solar energy that is reflected from the Earth into space.

Ice/Snow Albedo

Notably, ice/snow has a high albedo and hence, a large percentage of the sunlight will be reflected back into space instead of being absorbed.

This important characteristic of ice/snow is displayed through its white colour.

Essentially, a substance that we perceive to have a white colour reflects all light.

Therefore, ice and snow cools the Earth as it causes less of the sun's heat to be absorbed.

Ice-Albedo Feedback Loop

Unfortunately, as more ice melts due to global warming, there will be less sunlight reflected away and consequently, there will be even more warming.

This phenomenon is referred to as a feedback loop.

For more information on feedback loops, please see climate feedback.