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

Feedback processes in land-atmosphere interaction in a stochastic mode l of the soil and the turbulently mixed near-surface atmosphere hydrot hermal balance are identified. The model is forced by perturbations ab out the mean wind speed that advects air and water mass to the region. The fluctuations are routed within the system through the state depen dence of the radiative and thermal fluxes. Variabilities and covariabi lities that are evident in the output of the system are physically con sistent and in proportion due to the hydrologic and micrometeorologic constraints. The partitioning of the atmospheric radiative and moistur e forcing at the land surface is found to have significant influence o n the variability and covariability of temperature and moisture in the soil and atmosphere. Through a series of experiments with the stochas tic model of land-atmosphere interaction, the pathways and relative st rengths of the feedbacks are identified.