Do high latitude forests warm or cool climate?
Reported in the Guardian on 31 October 2008: Chemical released by trees can help cool planet, scientists find Planting forests is a popular way of reducing greenhouse gas concentrations and, apparently, slowing global warming. But forests have lots of other impacts on climate which make things more complicated. In fact, previous studies have suggested that trees at high latitudes (for example, in Europe) warm, rather than cool, the climate. These studies predict that dark forest vegetation absorbs more sunlight than farmland resulting in more warming than the cooling that is due to storage of carbon in forest vegetation. However, these studies did not consider that forests also produce particles. Particles are produced in the air above trees from natural emissions of terpene compounds (the compounds that give pine trees their distinctive smell). These particles reflect sunlight back to space and make clouds brighter, which acts to cool the climate. In a study published in the Philosoph
