Vast networks of meteorological sensors ring the globe measuring atmospheric state variables, like temperature, humidity, wind speed, rainfall, and atmospheric carbon dioxide, on a continuous basis. These measurements serve earth system science by providing inputs into models that predict weather, climate and the cycling of carbon and water. And, they provide information that allows researchers to detect the trends in climate, greenhouse gases, and air pollution. The eddy covariance method is currently the standard method used by biometeorologists to measure fluxes of trace gases between ecosystems and atmosphere.