A Sensor Network Application for Measuring Crop Evapotranspiration in California's Central Valley.

Wireless sensor networks provide opportunities for improving irrigation scheduling systems by providing information on crop evapotranspiration and real-time soil moisture and irrigation data.  As part of the NASA Satellite Irrigation Management Support project, we deployed wireless sensor networks in commercial agricultural fields across California to track precipitation, irrigation, soil moisture, and deep drainage, and to compute daily water budgets for multiple crops at the field scale. We present updated findings on the feasibility of using wireless sensor networks in commercial agricultural fields to measure key components of crop water budgets. We also present comparisons of estimated crop evapotranspiration derived from sensor networks against estimates from surface renewal instrumentation, as well as satellite-derived estimates from the NASA Terrestrial Observation and Prediction System. Results from this ongoing research will lead to a better understanding of how to apply data from satellite and ground-based sensor networks to support agricultural producers in optimizing irrigation scheduling.