Evapotranspiration (ET) from soil and vegetation is a key part of the energy and water budgets and, with condensation, a process that links both explicitly. Accurate experimental determination of ET is a requirement yet challenging both in situ and remotely. It introduces uncertainties for model parameterization development and validation. Furthermore, its representation often ignores important processes for specific conditions.
In the context of the Global Energy and Water cycles EXchanges core project (GEWEX) of the World Climate Research Programme (WCRP), there is a special interest in fostering research on the subject of Evapotranspiration, because activities in this topic are arguably not currently well coordinated or addressed within the program. To address this issue and foster the discussion, the GEWEX Hydroclimatology Panel (GHP) published a reflection paper (pg 5) in GEWEX News and organized a first ET workshop in 2019.
Hosted by Wageningen University & Research, the second ET workshop focussed on process understanding, with a strong observational component aided by process modelling studies. The online meeting was scheduled based along the 5 lines defined at the end of the 1st workshop:
i) open-water evaporation,
ii) interception (snow/ice sublimation),
iii) soil evaporation,
iv) transpiration and,
v) landscape ET/advection.
The aim of this workshop was to identify the main challenges in ET-research and how to tackle them with clear scientific goals and complete, integrative research strategies. The organization was a joint effort between the Meteorology and Air Quality Group (Oscar Hartogensis, Chiel van Heerwaarden, Jordi Vila, Mary Rose Mangan, Xabier Pedruzo Bagazgoitia) and the Hydrology and Quantitative Water Management Group (Ryan Teuling, Femke Jansen) in Wageningen, and Joan Cuxart.
The 2nd Evapotranspiration Workshop was dedicated to Jim Shuttleworth, who passed away peacefully on Sunday, December 20th, 2020.