Albedo is a measure of how reflective a surface is, how much light energy bounces off and reflects away and how much light energy gets absorbed. (Think hot asphalt on a sunny day. Black asphalt has a low albedo and absorbs light energy, while the brightest white has the highest albedo and reflects the light.) Albedo is part of what has stabilized Earth’s climate for millennia, because under normal conditions, the white of the polar ice reflects light energy back to space, keeping average global temperature stable. The more area covered by ice, the more heat reflected back to space. The more ice that melts, the more heat absorbed. Increasing temperatures are melting more ice, which exposes darker brown and green land and dark blue ocean. Those darker surfaces have a lower albedo, so they absorb more of the heat from the sun’s rays.
Today’s Word of the Day was Brought to You By:
Senior Science Editor at NASA-JPL
You can read her blog here: https://climate.nasa.gov/blog/2594/sun-and-sky-snow-and-ice/