Earths Heat Budget
Definition: The Balance between the incoming and outgoing heat.
Example:The heat that is absorbed into the earth, along with the heat that does not get absorbed into the earth is balanced. If this process becomes imbalanced, the earth with either heat up or cool down more than it should. The earth recives all of it's incoming radiation from solar energy. If an imbalance does occur, the tropics will become hotter and the poles will get even colder.
Albedo
Definition: Solar energy reflected from earth back into space.
Facts about Albedo:
-Ice with snow on top of it has a very high albedo. Water on the other hand, absorbs more solar radiation causing it to have a lesser albedo.
-On average, 30% of solar energy is reflected back into space.
-The albedo effect is the amount of radiation which is reflected by different surfaces. Below are a list of surfaces with the percentage reflected:
-Fresh snow reflects 80-85%
-Old snow reflects 50-60%
-Sand reflects 20-30%
-Grass reflects 25-30%
-Dry Soil reflects 15-25%
-Forest reflects 5-10%
Because the Albedo differs in different landscapes, it is becoming a huge problem because of global warming. If ice sheets start to melt because of the increase in climate change, we will start to see a decrease in the earths albedo.
The Greenhouse Effect:
The Greenhouse effect is a rise in temperature that the earth experiences due to certain gasses in the atmospher which trap energy from the sun. Some of these gasses are carbon dioxide, nitrous, oxide, and methane(also refered to as greenhouse gasses). If we didn't have these gasses, heat would get back into space causing the earths temperature to drop about 33 degrese C cooler.
Solar radiation:
Solar radiation is the energy emitted from the sun. This is the strongest energy that hits the earth and is intercepted by our atmosphere, and absorbed into the surface. These solar energys are X-Rays, ultroviolet, and infrared radiation.
Bibliography:
http://www.kidsgeo.com/geography-for-kids/0072-the-heat-budget.php
http://www.ucar.edu/learn/1_3_1.htm
http://www.eoearth.org/article/Solar_radiation
http://hyperphysics.phy-astr.gsu.edu/HBASE/phyopt/albedo.html
http://www.eoearth.org/article/Albedo
Thursday, February 12, 2009
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