Enhancing atmometer-based evapotranspiration monitoring using pressure transducer sensors

Accurate estimation of reference evapotranspiration (ET0) is key for precision irrigation. Traditional atmometers (ETgage) are affordable but limited by low temporal resolution. This study introduces an enhanced atmometer integrating pressure transducers for continuous, high-frequency monitoring of water level changes. Four sensors were calibrated, and the most responsive (RS-828-5708) was deployed in a kiwifruit orchard in southern Italy. Field results showed strong agreement between the enhanced atmometer and Penman–Monteith ET0, with minor discrepancies under intense radiation and dry conditions due to canvas and microclimate effects. A data-driven adjustment using solar radiation and canvas temperature improved accuracy; the pyranometer-based model performed best, while NASA reanalysis data yielded acceptable results. The innovation bridges low-cost instrumentation with high-resolution ET monitoring, offering a scalable solution for real-time irrigation management and supporting broader adoption of precision agriculture in resource-limited contexts.