Albedo is a measure of how much light or radiation is reflected by a surface. It is expressed as a fraction or percentage, with a value of 0 indicating no reflection and 1 indicating total reflection. For example, fresh snow has a high albedo, reflecting about 80-90% of sunlight, while dark surfaces like asphalt have a low albedo, reflecting only about 5-10%. Albedo plays a significant role in the Earth's climate system. Surfaces with high albedo can help cool the planet by reflecting sunlight, while those with low albedo can absorb heat, contributing to warming. Changes in albedo, such as from melting ice caps or deforestation, can impact global temperatures and weather patterns.