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'''Albedo''' is the fraction of solar radiation reflected from the earth and it's atmosphere. The higher the albedo the more reflective | '''Albedo''' is the fraction of solar radiation reflected from the earth and it's atmosphere. The higher the albedo the more reflective an object is. For example, snow has a very high albedo. Albedo is very important for determining positive feedback loops for [[global warming]] -- e.g. as the world heats up and snow cover recedes those areas absorb more solar energy and increase the rate of heating. Albedo is also important for the design of [[solar energy]] systems. | ||
* Albedo is a unit less number. | * Albedo is a unit less number. | ||
== Albedo measures == | |||
Albedo is a measure of how reflective a surface is. | |||
A reflective surface that reflects one hundred percent of the energy that strikes it has an albedo of 1. | |||
A black surface has an albedo of 0. Such a surface would absorb all of the energy from incoming radiation. | |||
A surface which was grey or some other similar colour would have an albedo that sits somewhere in between, around 0.5. | |||
Earth has an ''average'' albedo around .3, which varies depending on what the environment is in the place being assessed (ice, snow, tree, soil, plant cover, etc.). Other planets would have different albedos, affecting the amount of energy that stays within or leaves the system. | |||
The two Poles and deserts have high albedo and the oceans have low albedo. | |||
== Changes in land use patterns == | |||
Changes in the land use and land cover can impact albedo. While this is one source of contribution to climatic change, it is not the most significant contributor. | |||
{{stub}} | {{stub}} | ||
== See also == | |||
* [[Albedo of solar cells]] | |||
== Interwiki links == | |||
* [[Wikipedia:Albedo]] | |||
[[Category:PH261]] | [[Category:PH261]] | ||
[[Category:Physics]] | |||
[[Category:Climate change]] | |||
[[Category:Meteorology]] | |||
Revision as of 07:45, 25 November 2016
Albedo is the fraction of solar radiation reflected from the earth and it's atmosphere. The higher the albedo the more reflective an object is. For example, snow has a very high albedo. Albedo is very important for determining positive feedback loops for global warming -- e.g. as the world heats up and snow cover recedes those areas absorb more solar energy and increase the rate of heating. Albedo is also important for the design of solar energy systems.
- Albedo is a unit less number.
Albedo measures
Albedo is a measure of how reflective a surface is.
A reflective surface that reflects one hundred percent of the energy that strikes it has an albedo of 1.
A black surface has an albedo of 0. Such a surface would absorb all of the energy from incoming radiation.
A surface which was grey or some other similar colour would have an albedo that sits somewhere in between, around 0.5.
Earth has an average albedo around .3, which varies depending on what the environment is in the place being assessed (ice, snow, tree, soil, plant cover, etc.). Other planets would have different albedos, affecting the amount of energy that stays within or leaves the system.
The two Poles and deserts have high albedo and the oceans have low albedo.
Changes in land use patterns
Changes in the land use and land cover can impact albedo. While this is one source of contribution to climatic change, it is not the most significant contributor.