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The Bond albedo is a value strictly between 0 and 1, as it includes all possible scattered light (but not radiation from the body itself). This is in contrast to other definitions of albedo such as the geometric albedo, which can be above 1. In general, though, the Bond albedo may be greater or smaller than the geometric albedo, depending on ...
The brightness usually refers the object's absolute magnitude, which, in turn, is its apparent magnitude at a distance of one astronomical unit from the Earth and Sun. The phase curve is useful for characterizing an object's regolith (soil) and atmosphere. It is also the basis for computing the geometrical albedo and the Bond albedo of the
The average albedo of Earth is about 0.3. [15] This is far higher than for the ocean primarily because of the contribution of clouds. Earth's surface albedo is regularly estimated via Earth observation satellite sensors such as NASA's MODIS instruments on board the Terra and Aqua satellites, and the CERES instrument on the Suomi NPP and JPSS.
Cloud albedo strongly influences the Earth's energy budget, accounting for approximately half of Earth's albedo. [1] [2] Cloud albedo is influenced by the conditions of cloud formation and variations in cloud albedo depend on the total mass of water, the size and shape of the droplets or particles and their distribution in space. [3]
Earth has an albedo of about 0.306 and a solar irradiance (L / 4 π D 2) of 1361 W m −2 at its mean orbital radius of 1.5×10 8 km. The calculation with ε=1 and remaining physical constants then gives an Earth effective temperature of 254 K (−19 °C). [11] The actual temperature of Earth's surface is an average 288 K (15 °C) as of 2020. [12]
The albedo of several types of roofs (lower values means higher temperatures). Reflective surfaces, or ground-based albedo modification (GBAM), is a solar radiation management method of enhancing Earth's albedo (the ability to reflect the visible, infrared, and ultraviolet wavelengths of the Sun, reducing heat transfer to the surface).
An albedometer is an instrument used to measure the albedo (reflecting radiation) of a surface. An albedometer is mostly used to measure the reflectance of earths surface. It is also useful to evaluate thermal effects in buildings and generation capacity with bifacial solar photovoltaic panels. Often it consists of two pyranometers: one facing ...
Diffuse reflection on sphere and flat disk, each for the case of a geometric albedo of 1. For the hypothetical case of a plane surface, the geometric albedo is the albedo of the surface when the illumination is provided by a beam of radiation that comes in perpendicular to the surface.