Reforestation is good for fighting change because trees absorb CO2, above and beyond the other environmental goodness they produce, but … (there’s always a “but” ) … new work from Elizabeth Burakowski, a postdoctoral research associate at UNH, shows one potential drawback: New forests decrease the albedo, or reflectiveness, of land compared to fields and scrubland.
Decreasing the albedo of land is associated with increased global warming – it’s one of the scary positive-feedback loops resulting from the loss of snow cover and permanent glaciers. So does that mean regrowing forests can increase global warming?
The researchers say that it is important to note that this study focused on albedo and that other surface properties related to land cover can also affect surface climate, such as how much water is moved from the vegetation to the atmosphere and how rough a canopy is, which can affect the redistribution of energy at the surface. While reforestation is a likely contributor to historical warming trends in the New England region, the researchers say more studies are needed to determine how much of the warming from that time to the present is due to land cover change and how much is due to other factors like greenhouse gas emissions and natural climate change.
That’s from the press release (here). As is often the case in science, as in life, answering one question raises two more.