2023 de NOVIEMBRE 01
A new method for estimating cumulative evapotranspiration using superconducting gravimeter data is presented. The evapotranspiration is computed from the classical water balance equation using precipitation data, estimated values of runoff, and water storage assessed from temporal variations of gravity. The gravity-based methodology is applied to a study site located at the Argentinian-German Geodetic Observatory (AGGO) in the flatland area of Buenos Aires Province (Argentina) which houses the only superconducting gravimeter in South America. For the time period from April 2017 to May 2018, the cumulative evapotranspiration is estimated at 710.7 mm ± 25.7 mm. Evapotranspiration values are successfully compared with estimates provided by three different methods based on the water balance equation using soil moisture data, the numerical modeling of water flow in the unsaturated zone and on MODIS product (MOD16A2). The analysis of the evapotranspiration also allows to identify a period of soil water stress which are validated by soil moisture measurements.