# Have Humans Altered the Albedo of the Earth?

**URL:** <https://boards.straightdope.com/t/have-humans-altered-the-albedo-of-the-earth/433062>\
**Category:** Factual Questions\
**Created:** [January 11, 2008, 12:47am UTC](https://boards.straightdope.com/t/have-humans-altered-the-albedo-of-the-earth/433062 "2008-01-11T00:47:55Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![ralph124c](https://avatars.discourse-cdn.com/v4/letter/r/8797f3/32.png) [@ralph124c](https://boards.straightdope.com/u/ralph124c)\
**Post date:** [January 11, 2008, 12:47am UTC](https://boards.straightdope.com/t/have-humans-altered-the-albedo-of-the-earth/433062/1 "2008-01-11T00:47:55Z")

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To any significant degree? Reading about (Russian) astronomer Dr. Abdumasatov’s contention that the solar output is the main driver of the climate, I wonder if human activity has reduced the reflection of solar radiation. For example, the highways we have built-they absorb a lot more energy than the forest/grasslands they replaced. Are there any estimates of how much humans have altered the reflection of solar energy?

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**Author:** ![Squink](https://avatars.discourse-cdn.com/v4/letter/s/b5e925/32.png) [@Squink](https://boards.straightdope.com/u/Squink)\
**Post date:** [January 11, 2008, 12:59am UTC](https://boards.straightdope.com/t/have-humans-altered-the-albedo-of-the-earth/433062/2 "2008-01-11T00:59:08Z")

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[Moonglow Sheds Light on Earth’s Climate](http://www.nasa.gov/vision/earth/lookingatearth/earthshine.html)

> [@](#):
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> Scientists looked at the ghostly glow of light reflected from Earth onto the moon’s dark side. During the 1980s and 1990s, Earth bounced less sunlight out to space. The trend reversed during the past three years, as the Earth appears to reflect more light toward space.
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> Though not fully understood, the shifts may indicate a natural variability of clouds, which can reflect the sun’s heat and light away from Earth. The apparent change in the amount of sunlight reaching Earth in the 1980s and 1990s is comparable to taking the effects of greenhouse gas warming since 1850 and doubling them. Increased reflectance since 2001 suggests change of a similar magnitude in the opposite direction.

[MODIS](http://modis.gsfc.nasa.gov/)

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**Author:** ![Jinx](https://avatars.discourse-cdn.com/v4/letter/j/c6cbf5/32.png) [@Jinx](https://boards.straightdope.com/u/Jinx)\
**Post date:** [January 11, 2008, 3:00am UTC](https://boards.straightdope.com/t/have-humans-altered-the-albedo-of-the-earth/433062/3 "2008-01-11T03:00:10Z")

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No, but we’ve done quite a lot to boost the earth’s libido! 😃 Old astronomy joke… But seriously, folks, unless we’re gonna spill enough oil to paint the oceans black, I wouldn’t worry…

Try the veal, I’ll be here all weak (sick, sic) 😃