Please note that this session was withdrawn and is no longer available in the respective programme. This withdrawal might have been the result of a merge with another session.
HS10.10 | Scaling evapotranspiration from in-situ measurements – approaches and uncertainties
Scaling evapotranspiration from in-situ measurements – approaches and uncertainties
Convener: Sibylle K. Hassler | Co-conveners: Jannis GrohECSECS, Harrie-Jan Hendricks Franssen, Corinna Rebmann
Evapotranspiration (ET) is the key water flux at the interface of soil, vegetation and atmosphere. Methods for in-situ measurements of this flux or its individual components have been developed in various research disciplines, covering different scales from point scale of e.g. point scale sap flow or soil heat pulse measurements, pedon-scale of lysimeters, ecosystem scale of eddy covariance footprints to the landscape scale via drones or scintillometers. Bridging these scales while considering and communicating method-specific uncertainties still remains a tremendous challenge. However, scaling procedures are needed to enable meaningful comparisons between different ET measurements and to spatially distributed ET estimates at larger scales, e.g. from remote sensing or modelling.

The session will mainly focus on the variety of ET estimates from different in-situ devices such as sap flow or soil heat pulse sensors, lysimeters, eddy covariance stations, scintillometers, and other (possibly new) methods. Additionally, we want to address the scale dependency of the various approaches as well as strategies to handle uncertainties, systematic biases and representativity of the estimates when attempting to bridge scales, e.g. to compare in-situ measurements with remote sensing or modelling products at catchment- or landscape scale. We welcome contributions that (1) assess and compare established and new in-situ ET measurements, (2) address systematic errors and uncertainty of the respective methods, (3) analyse trends as well as spatial and temporal patterns in in-situ measured ET data, (4) include cross-scale comparisons and scaling approaches, and (5) incorporate in-situ measurements into modeling approaches