science: Be sustainable and cut more trees

TREES are good. Good enough to hug. Trees have a nifty biochemical 
strategy called photosynthesis that enables them to take carbon dioxide 
in through their leaves, and swap that nasty gas for oxygen, a nice one. 
They use the carbon thus sequestered to make molecules like cellulose, 
and thus more tree.

That is why some rich people who love to burn things containing carbon, 
such as petrol and aircraft fuel, have recently started paying others to 
plant trees on their behalf. Burning adds oxygen to carbon, making 
carbon dioxide. And carbon dioxide makes the world warmer. A warmer 
world will mean higher sea levels. So if people burn things without 
offsetting the carbon dioxide thus produced, their holidays in the 
Maldive islands will disappear, along with the islands themselves.

This chattering-class environmental picture is not necessarily wrong, 
but it does include many assumptions. One of them, that planting trees 
will make the world cooler than it would otherwise be, is the subject of 
a newly published study by Govindasamy Bala, of the Lawrence Livermore 
National Laboratory, in California, and his colleagues. Dr Bala has 
found, rather counter-intuitively, that removing all of the world's 
trees might actually cool the planet down. Conversely, adding trees 
everywhere might warm it up.


cont'd....
http://economist.com/science/displaystory.cfm?story_id=8998216