TY - JOUR
T1 - A New Post‐Hoc Method to Reduce the Energy Imbalance in Eddy Covariance Measurements
AU - Zhang, Weijie
AU - Nelson, Jacob A.
AU - Miralles, Diego G.
AU - Mauder, Matthias
AU - Migliavacca, Mirco
AU - Poyatos, Rafael
AU - Reichstein, Markus
AU - Jung, Martin
N1 - Publisher Copyright:
© 2024. The Authors.
PY - 2024/1/28
Y1 - 2024/1/28
N2 - Latent and sensible heat flux observations are essential for understanding land–atmosphere interactions. Measurements from the eddy covariance technique are widely used but suffer from systematic energy imbalance problems, partly due to missing large eddies from sub-mesoscale transport. Because available energy drives the development of large eddies, we propose an available energy based correction method for turbulent flux measurements. We apply our method to 172 flux tower sites and show that we can reduce the energy imbalance from −14.99 to −0.65 W m−2 on average, together with improved consistency between turbulent fluxes and available energy and associated increases in r2 at individual sites and across networks. Our results suggest that our method is conceptually and empirically preferable over the method implemented in the ONEFlux processing. This can contribute to the efforts in understanding and addressing the energy imbalance issue, which is crucial for the evaluation and calibration of land surface models.
AB - Latent and sensible heat flux observations are essential for understanding land–atmosphere interactions. Measurements from the eddy covariance technique are widely used but suffer from systematic energy imbalance problems, partly due to missing large eddies from sub-mesoscale transport. Because available energy drives the development of large eddies, we propose an available energy based correction method for turbulent flux measurements. We apply our method to 172 flux tower sites and show that we can reduce the energy imbalance from −14.99 to −0.65 W m−2 on average, together with improved consistency between turbulent fluxes and available energy and associated increases in r2 at individual sites and across networks. Our results suggest that our method is conceptually and empirically preferable over the method implemented in the ONEFlux processing. This can contribute to the efforts in understanding and addressing the energy imbalance issue, which is crucial for the evaluation and calibration of land surface models.
KW - Bowen-ratio correction
KW - available energy flux
KW - eddy covariance
KW - energy balance closure
KW - latent and sensible heat flux
KW - sub-mesoscale transport
UR - http://www.scopus.com/inward/record.url?scp=85183903905&partnerID=8YFLogxK
UR - https://www.mendeley.com/catalogue/08ca2db6-0964-3dea-a167-fc7ef32978cf/
U2 - 10.1029/2023GL107084
DO - 10.1029/2023GL107084
M3 - Article
SN - 1944-8007
VL - 51
JO - Geophysical Research Letters
JF - Geophysical Research Letters
IS - 2
M1 - e2023GL107084
ER -