9 - Forest Biometeorology

Summary

Energy transfers between the biosphere and atmosphere affect climate. These include radiative exchange, seen, for example, in the warmth of sunlight; convection, experienced in the cooling influence of a breeze; evaporation; and conduction of heat in the soil. These fluxes depend on the biophysical and physiological characteristics of plants. In addition, plants remove carbon dioxide from the atmosphere during their growth and emit many chemical species to the atmosphere. Biometeorology is a field of science that studies the interactions between the biosphere and the atmosphere through energy, water, and chemical exchanges. These are regulated by the amount of water in the soil, and so the hydrologic cycle is closely coupled to the energy and chemical cycles. Seasonal changes in leaves, both foliar chemistry and the amount of leaves in the canopy, drive short-term variation in energy, water, and chemical fluxes. The growth of vegetation, accumulation of carbon in plant biomass and soil, and changes in floristic composition cause longer-term changes in biosphere-atmosphere coupling over periods of decades, centuries, and millennia.