How do you calculate surface albedo?
How do you calculate surface albedo?
How do you calculate albedo? Albedo can be measured using satellite imagery or a pyranometer device. Both can detect the reflection of shortwave solar radiation in the form of watts per square meter (W/sq m). Simply, albedo can be calculated using the basic equation Albedo = Reflected Light/Incoming Light.
What is albedo in remote sensing?
The albedo is defined as the ratio between the reflected energy and the incident energy over a unit area, from which it can be inferred that there is some similarity between the albedo and the reflectance. From: Advanced Remote Sensing, 2012.
What is surface albedo?
Albedo is an expression of the ability of surfaces to reflect sunlight (heat from the sun). Light-coloured surfaces return a large part of the sunrays back to the atmosphere (high albedo). Dark surfaces absorb the rays from the sun (low albedo).
What is the value of albedo?
Albedo varies between 0 and 1. Albedo commonly refers to the “whiteness” of a surface, with 0 meaning black and 1 meaning white. A value of 0 means the surface is a “perfect absorber” that absorbs all incoming energy.
What is albedo and How Is It Measured?
Albedo is a measure of reflectivity. It is the ratio of the solar radiation (short wave radiation) reflected by a surface to the total incoming solar radiation. Albedo can either be expressed in a ratio (dimensionless number) or as a percentage. The higher the value, the more energy is reflected back to the source.
Is albedo influenced by land cover?
Abstract. Land cover changes (e.g., forest to grassland) affect albedo, and changes in albedo can influence radiative forcing (warming, cooling).
How do satellites measure albedo?
Methods used to validate satellite-derived albedo measurements are accomplished with a pair of pyranometers, one measuring the incoming radiation and the other measuring the radiation reflected from the surface.
Which land surface has the highest albedo?
Snow and ice have the highest albedos of any parts of Earth’s surface: Some parts of Antarctica reflect up to 90% of incoming solar radiation.
Which one of the following land surfaces has the highest albedo?
The desert areas have some of the highest albedos among landforms. Most land areas are in an albedo range of 0.1 to 0.4. The average albedo of Earth is about 0.3. Any albedo in visible light falls within a range of about 0.9 for fresh snow.
What has an albedo of 100%?
Albedo is the percentage of solar radiation reflected by an object. The term is derived from the Latin albus, white. A pure white object would reflect all radiation that impinges on it and have an albedo of 100%.
What factors affect albedo?
Ice and snow, deserts, clouds, aerosols (particles in the air) all reflect sunlight. The higher albedo, the more solar energy reflected; the colder. When it is getting colder, ice cover expands, thus also increasing the albedo.
What units are used for albedo?
High albedo surfaces are light, such as snow, ice, or sand, and reflect most of the incoming solar radiation back into the atmosphere. Incoming solar radiation is measured in Watt/m2, and the instrument that is used for the measurement is called a pyranometer.