ScienceDaily (July 26, 2011) — Decisions by farmers to plant on productive land with little snow enhances the potential for reforestation to counteract global warming, concludes new research from Carnegie's Julia Pongratz and Ken Caldeira. Previous research has led scientists and politicians to believe that regrowing forests on Northern lands that were cleared in order to grow crops would not decrease global warming. But these studies did not consider the importance of the choices made by farmers in the historical past.
Press release on study out 1 month ago:
...But the study says the benefits of tree planting are "marginal" when it comes to stopping the planet from overheating.
Trees do suck carbon [dioxide] out of the air, but the study highlights that their dark leaves and needles also decrease the amount of solar radiation that gets reflected by the landscape, which has a warming effect...