AN ANALYTIC APPROACH TO MODELING LAND ATMOSPHERE INTERACTION .2. STOCHASTIC FORMULATION

Feedback processes in land-atmosphere interaction in a stochastic model of the soil and the turbulently mixed near-surface atmosphere hydrothermal balance are identified. The model is forced by perturbations about the mean wind speed that advects air and water mass to the region. The fluctuations are routed within the system through the state dependence of the radiative and thermal fluxes. Variabilities and covariabilities that are evident in the output of the system are physically consistent and in proportion due to the hydrologic and micrometeorologic constraints. The partitioning of the atmospheric radiative and moisture forcing at the land surface is found to have significant influence on the variability and covariability of temperature and moisture in the soil and atmosphere. Through a series of experiments with the stochastic model of land-atmosphere interaction, the pathways and relative strengths of the feedbacks are identified.