Welcome to the model Simsphere, a state-of-the art Soil-Vegetation-Atmosphere Transfer (SVAT) model for use by the general scientific community. Simsphere is a product of 30 years of continuous experience and utilization by my students and myself at Penn State. Simsphere is a one-dimensional model that allows one to simulate the transfer of heat and moisture between plants, soil and atmosphere over a 24 hour day.