Another major factor in the global warming debate is deforestation.  
Clearing massive acreage that was once rainforest is a double-whammy.  
The agriculture that takes place on the cleared land adds to the 
problem, as has been described previously, and the reduction in 
rainforest acreage limits the earth's ability to convert carbon dioxide 
back into oxygen.  One blip I heard on NPR explained how clearing 
rainforest messes with the global carbon cycle even more than feedlot 
meat production or petroleum use.

Lisa Sporleder

Robert Kesterson wrote:

>Kathryn Rosenthal wrote:
>  
>
>>A vegetarian from another list (obviously) sent this to me.
>>
>>This week, NASA climatologists said that new data suggests 
>>that the Arctic Ocean may have no more ice by 2012. ...
>>the presence of the Arctic sea ice reflects about 80% of
>>the sun's heat, stabilizing the temperature of the ocean.
>>    
>>
>
>Except for one thing -- losing the ice does not necessarily mean losing
>the reflectivity.  In fact, studies have already been done on this very
>thing.  The melting ice results in increased cloud cover, which
>essentially cancels out any loss in reflectivity.  See this page for
>discussion:
>http://earthobservatory.nasa.gov/Study/ArcticReflector/arctic_reflector4.html
>  
>
>  
>