Via ecogeek.org, 23-09-2011
Scientists at the Carnegie Institution’s Global Ecology department have published a study that found that evaporation from trees has a cooling effect on the climate.
Because water vapor is known to act as a greenhouse gas, scientists were unsure what role evaporation played, but it turns out that evaporation from trees causes low-level clouds to form in the atmosphere, which reflect the sun’s rays. The scientists created models that showed that not only did cooling occur locally (which was already known), but that the effect was a global one where tree evaporation created more low-level clouds around the world.
via Yale e360