For example, for the Earth, the albedo is 0.306 and the distance is 1.000 AU, so the expected temperature is 254 K or -19 C ---significantly below the freezing point of water! A planet completely covered with snow or ice would have an albedo close to 100%, while a completely dark planet would have an albedo close to zero. ). Hopefully there will be examples of these values here later. While bi-hemispherical reflectance is calculated for a single angle of incidence (i.e., for a given position of the Sun), albedo is the directional integration of reflectance over all solar angles in a given period. Calculate heat absorption using the formula: Q = mc∆T. Our priors are on the differences of log-albedo, which makes them equivalent to priors on the ratios of albedo. Question: How does albedo relate to the amount of energy absorbed by a planet? To calculate the actual amount of the solar energy flux that is absorbed by the atmosphere and surface of a planet, we have to account for the albedo by reducing the incoming flux by a factor of 1 – α. By definition, daily mean albedo can be estimated by first calculating instantaneous albedo at various local times from the MODIS BRDF products and then averaging the instantaneous values with the incident radiation as a weight. This is not the same amount everywhere as the amount changes in different parts of the Earth and in seasons. Example: of 1000 watts light falling on a sand desert, about 300 watts are reflected, 700 are absorbed. For most (if not for all) surfaces the albedo depends on the wavelength of the incoming radiation. Or in other words, the fraction of the incoming radiation which is reflected. A simple definition of albedo (a) is the average reflectance of the sun’s spectrum. Measure the light from the area you want to know the albedo (in the below example image, the grass). Q means the heat absorbed, m is the mass of the substance absorbing heat, c is the specific heat capacity and ∆T is the change in temperature. In the examples, there are a description where the lightening has happened, for how long, for how big area in square meters, how much the change in albedo was in megajoules and the megajoules transferred into gasoline litres. The albedo is the ratio between the reflected irradiation and the total irradiance. http://imagej.nih.gov/ij/index.html
 The value tells, how many percent of the incoming light is reflected. The difference between actual temperature values and the calculated values for the other three planets are a bit more interesting because of the effect of their atmospheres. Zero corresponds to a black body that absorbs all incident radiation, such as wet coal, and 1 corresponds to a body that reflects all incident radiation, similar to fresh snow. The albedo of the entire Earth can be estimated by analyzing aerial and satellite pictures of the Earth. Land cover that is light in color has high albedo whereas dark colors have low albedo. It is a property of the ground surface. Calculate black-sky, white-sky, and actual albedo from MODIS MCD43A1 BRDF parameters product with custom solar zenith angle and solar optical depth inputs. Albedo . Lectures by Walter Lewin. Snow reflects almost all the sunlight that hits it so its albedo … Write down the value. One megajoule is 42,4 l of gasoline. The difference between actual temperature values and the calculated values for the other three planets are a bit more interesting because of the effect of their atmospheres. This talk will focus on the submicron aerosols. Description of albedo for grade 10 science. The basics is the same with all the software – below it is explained with ImageJ. For a low albedo, as on Mercury, the factor is near unity and most of the incoming energy is absorbed. An open source image editing software ImageJ is freely downloadable at This is called "BOND ALBEDO." Albedo, also called solar reflectance, is defined as the ratio of the reflected to the global radiation. Measures average brightness of each pixel in the selected area ( normally ). With your camera of the sun simply affects the amount of incident energy on the planet Neptune data! How many percent of the incoming sunlight back into space the downfacin… to. 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