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Michael F
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| Joined: | Tue Oct 16th, 2007 |
| Location: | Holtsville, New York USA |
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Posted: Tue Oct 7th, 2008 02:58 am |
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it says that radiant energy rreceived on a surface that is reflected is called Albedo and ranges from 0.0 to 1.0.
Zero albedo is flat black surface tgat absorbs all the energy and reflects none.
1.0 albedo is like a mirror reflecting all energy.
So, How can snow and pavement have high albedos.
I can understand snow but why pavement, shouldnt the book say that pavement is a low albedo?
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icarusburns
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Posted: Tue Oct 7th, 2008 04:20 am |
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Pavement has a low albedo - but high absorption. Perfectly black pavement would have an albedo close to zero (0), at least that's the way I understand it.
. . . Although, it seems like I have the same sentence in my ALS guide as you that reads "Pavements have high albedo".
Anyone else on this?
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hugon0
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Posted: Tue Oct 7th, 2008 02:57 pm |
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Michael F wrote: it says that radiant energy rreceived on a surface that is reflected is called Albedo and ranges from 0.0 to 1.0.
Zero albedo is flat black surface tgat absorbs all the energy and reflects none.
1.0 albedo is like a mirror reflecting all energy.
So, How can snow and pavement have high albedos.
I can understand snow but why pavement, shouldnt the book say that pavement is a low albedo?
try this
http://www.areforum.org/forums/forum23/61536.html
there are 2 concepts at work here, and Kaplan (and Ballast) kind of treat it like 1, which makes it more confusing.
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Michael F
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Posted: Wed Oct 8th, 2008 06:47 pm |
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| Thanks Hugon. This helps a little.
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Current time is 11:17 pm | |
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