Project Funding: 2013 - 2016

NRA: 2013 NASA: Carbon Monitoring System   

Funded by NASA

Abstract:
This proposal develops a prototype system that combines commercial ground-based measurement techniques with satellite data to address Monitoring, Reporting and Verification (MRV) of regional CO2 fluxes from fossil fuel emissions and biospheric exchange. The system will be centered on the State of California, where it will be responsive to the State's policy measure to reduce greenhouse gas emissions, California's Global Warming Solutions Act (AB-32) which includes a cap-and-trade program, and where a relatively dense measurement network for atmospheric CO2 concentration is already in place. We will use this existing network to conduct field sampling for the measurement of radiocarbon content (D14C) in atmospheric CO2 that will enable us to identify fossil-derived and biospheric-derived CO2 [Turnbull et al. 2006; Graven et al. 2009] at 9 sites across the state. The D14C-based observations of fossil-derived and biospheric-derived CO2, along with measurements of total CO2 concentration from ground-based and satellite platforms, will be analyzed in an atmospheric inversion framework that we will develop from a similar framework currently being used to estimate emissions of CH4 in California [Jeong et al. 2012; Fischer et al. 2012]. Unique contributions of the proposed work involve the integration of D14C data into an inversion framework to optimize fossil fuel emissions explicitly, and the integration of satellite-derived total column CO2 with ground-based data. The proposed work will also provide evaluation of the natural sink or source of CO2 in California's terrestrial biosphere and evaluation of the biospheric models, CASA-GFED and NASA-CASA, across the widely varying biome types and land uses present in California. These models incorporate satellite retrievals of vegetation index and land cover and are currently used in the NASA Carbon Monitoring System Flux Product. Data products resulting from the proposed work include optimized CO2 flux distributions and totals, including uncertainty, for the State of California for both fossil fuel emissions and biospheric exchange, providing an atmospheric observation-based MRV product that can be used to support California's AB-32 policy. The prototype system we develop could be replicated in other regions, providing similar MRV applications to other greenhouse gas emission policies.

Publications:

Brophy, K., Graven, H., Manning, A. J., White, E., Arnold, T., Fischer, M. L., Jeong, S., Cui, X., Rigby, M. 2019. Characterizing uncertainties in atmospheric inversions of fossil fuel CO<sub>2</sub> emissions in California. Atmospheric Chemistry and Physics. 19(5), 2991-3006. DOI: 10.5194/acp-19-2991-2019

Fischer, M. L., Parazoo, N., Brophy, K., Cui, X., Jeong, S., Liu, J., Keeling, R., Taylor, T. E., Gurney, K., Oda, T., Graven, H. 2017. Simulating estimation of California fossil fuel and biosphere carbon dioxide exchanges combining in situ tower and satellite column observations. Journal of Geophysical Research: Atmospheres. 122(6), 3653-3671. DOI: 10.1002/2016JD025617

Graven, H., Fischer, M. L., Lueker, T., Jeong, S., Guilderson, T. P., Keeling, R. F., Bambha, R., Brophy, K., Callahan, W., Cui, X., Frankenberg, C., Gurney, K. R., LaFranchi, B. W., Lehman, S. J., Michelsen, H., Miller, J. B., Newman, S., Paplawsky, W., Parazoo, N. C., Sloop, C., Walker, S. J. 2018. Assessing fossil fuel CO 2 emissions in California using atmospheric observations and models. Environmental Research Letters. 13(6), 065007. DOI: 10.1088/1748-9326/aabd43

More details may be found in the following project profile(s):

• North American Carbon Program (NACP) Project Profile
• NASA Carbon Monitoring System (CMS) Project Profile