The ALEX (Atmosphere-Land EXchange) model simulates the transport of heat, water and carbon between a vegetated surface and the overlying air mass. ALEX is sufficiently detailed in its representation of the soil-plant-atmosphere system that it accurately reproduces fluxes measured in the field under a variety of conditions. At the same time, ALEX is simple enough that it can be easily ported to a wide range of applications. We have used the ALEX model as a core for several agricultural modeling products, including a frost forecasting system for cranberry growers and an indicator of leaf blight outbreak potential in potato crops. ALEX has also been incorporated into a three-dimensional surface runoff simulator for studying the delivery of non-point source pollutants across a landscape. The simplicity of the ALEX equation set makes it easily invertible, resulting in a version of the model that can be driven by remotely-sensed inputs. This inverted form of ALEX (dubbed ALEXI) shows great potential in modeling regional-scale evapotranspiration and carbon assimilation fluxes.
Special Session -- Weather Data Requirements for Integrated Pest Management