Simulations of Water and Energy Budgets (Diagnostic Subproject 17) Simulations from one of the AMIP global models (GENESIS) and a regional-scale model are compared and contrasted with respect to the ensemble effects of subsynoptic moisture and heat transports, cloud and radiative effects, and precipitation on the energy and water cycles. The comparison region is essentially the Mississippi Basin. GENESIS does not prognose cloud and rain water explicitly, instead it diagnoses these parameters. On the other hand, the regional-scale numerical model includes explicit predictive equations for cloud and rain water. To compare and contrast the water and energy budgets resulting from the GENESIS diagnostic procedures with the budgets from the regional-scale model prognostic procedures, long-term (greater than 10 days) simulations were performed.
The limiting errors in budget calculations performed using GENESIS versus
the regional-scale model are evaluated and the sensitivity of the modeled
regional energy and water balance to model grid scale and physics is evaluated.