Anthropogenic CO2 flux constraints in the Tokyo Bay Area from Lagrangian diffusive backward trajectories and high resolution in situ measurements
1Research Institute for Global Change, JAMSTEC, Yokohama 236 0001, Japan
2National Institute for Environmental Studies, Tsukuba, Ibaraki 305-8506, Japan
3Meteorological Research Institute, Tsukuba, Ibaraki, 305-0052 Japan
Abstract. In order to use high resolution in-situ measurements to constrain regional emissions of carbon dioxide (CO2), we use a Lagrangian methodology based on diffusive backward trajectory tracer reconstructions. We use aircraft, tall tower and ground sites for CO2 data collected nearby the CO2 emission hot spot of the Tokyo Bay Area during the CONTRAIL campaign, from the MRI/JMA Tsukuba tall tower and from the World Data Centre for Greenhouse Gases (WDCGG). We calculated Bayesian inversions based on EDGAR 4 and CDIAC a priori fluxes. Estimated fluxes for the Tokyo Bay Area for the analyzed period between 2005 and 2009 range between 4.80×10−7 and 3.45×10−6 kgCO2 m2 s−1 with significant time variations. Significant differences in retrieved fluxes of up to 21% were found when CONTRAIL measurements were added to the dataset. No significant trend was found in the time series of spatially averaged retrieved fluxes.