Evapotranspiration measurements from eddy covariance: network-level insights, energy balance closure, and emerging imperatives

2015 Spring Cyberseminar Series

Paul Stoy / Montana State University

Talk Description:

The eddy covariance system measures the surface-atmosphere exchange of heat, momentum, water, and certain trace gases, and is an increasingly popular approach for quantifying the impacts of the land surface on the atmosphere and vice versa. A number of challenges and opportunities arise when interpreting eddy covariance evapotranspiration measurements. First and foremost is the issue of energy balance closure: the energy balance of the surface is rarely closed and the culprit across the FLUXNET network of 500+ towers is uncertain. Furthermore, eddy covariance measures evapotranspiration, but a process-level understanding of evaporation and transpiration are often desired. I will explain eddy covariance measurements of evapotranspiration after briefly deriving the Penman-Monteith equation to motivate the connections between measurements and modeling. I will then discuss site-level and network-scale evapotranspiration analyses and emerging methods that are being explored to partition evaporation and transpiration from eddy covariance evapotranspiration measurements. Opportunities for incorporating eddy covariance into hydrological science will be outlined and a future prospectus for linking NEON eddy covariance observations with water cycle science will be described.

CUAHSI's Spring 2015 Cyberseminar Series on  Evapotranspiration - Frontiers in measurement, modeling and management from the leaf to the landscape!

Hosted by Steven Brantley, Joseph W. Jones Ecological Research Center