Forests emit large quantities of volatile organic compounds (VOCs) to the atmosphere, a recent study has found, and their condensable oxidation products can form secondary organic aerosol, which is known to affect the Earth’s radiation balance by scattering solar radiation and by acting as cloud condensation nuclei.
In short, VOCs act as a cooling agent and promote cloud formation.
The research, published in the scientific journal Nature said: "We find that a direct pathway leads from several biogenic VOCs, such as monoterpenes, to the formation of large amounts of extremely low-volatility vapors. These vapors form at significant mass yield in the gas phase and condense irreversibly onto aerosol surfaces to produce secondary organic aerosol, helping to explain the discrepancy between the observed atmospheric burden of secondary organic aerosol and that reported by many model studies," the report said.
The study reviewed the oxidation of VOCs, in particular the terpene α-pinene, under atmospherically relevant conditions in chamber experiments.