Albedo is a unitless quantity that indicates how well a surface reflects solar energy. Albedo (α) ranges from 0 to 1, with 0 representing a black surface that absorbs 100% of energy and 1 representing a white surface that reflects 100% of energy. The presence of ice, and to a greater extent snow-covered ice, on dark surfaces (such as the ocean) increase albedo.
National Snow and Ice Data Center. Thermodynamics: Albedo; in All About Sea Ice; National Snow and Ice Data Center. https://nsidc.org/cryosphere/seaice/processes/albedo.html