Eddy covariance network design for mapping and quantification of surface CO2 leakage fluxes

Abstract

We develop a method to design an eddy covariance (EC) network to enhance monitoring of the spatial distribution and magnitude of a surface CO2 flux leakage signal. Integrated and distributed estimates of CO2 surface flux inferred using the network are used to assess trade-offs between number and location of stations, and the determination of the surface flux distribution. We applied this method to a surface CO2 flux leakage signal generated by a controlled CO2 release conducted in the shallow subsurface in Bozeman, MT. At this site, three EC stations provide definition of the spatial distribution of this CO2 leakage signal, and quantify total CO2 leakage discharge. Results provide a means of designing experiments to map the spatio-temporal distribution of CO2 leakage fluxes and quantify total leakage rate in areas where a priori information may be used to infer likely scenarios for surface flux distributions.