Mrs. Evaporation: The Big Forest Ghost

Abstract:

You can sense her presence, but mostly you can’t see her. Only sometimes she is showing her erratic behavior: Mrs. Evaporation. Scooby-Doo and the team of Mystery Inc. are already trying for ages to understand her personality, but still they have little clue. Yes, they have installed e.g., eddy covariance systems, but frequently these outcomes do not match the estimates by water and/or energy balances. Why?! Why is it so difficult to catch Mrs. Evaporation?

In this talk I will outline some of the processes that could explain why it is so difficult to measure evaporation in forest systems. Temperature and humidity profiles measured with Distributed Temperature Sensing (DTS) at high temporal and spatial resolution, visual observations, stable water isotopes observations (both liquid as vapor), and lysimeter data are all pieces of the puzzle. They show the complexity of what is happening within forests, as well as the importance of considering all subcomponents of Mrs. Evaporation, i.e. transpiration, interception, and soil evaporation. However, still new pieces are necessary. For example, could it be possible to catch the entire surface energy balance at the right spatiotemporal scale? In this talk I will outline the first sketches of this idea, where I aim to achieve this with a single sensor.