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Title: Simulating estimation of California fossil fuel and biosphere carbon dioxide exchanges combining in situ tower and satellite column observations

Here, we report simulation experiments estimating the uncertainties in California regional fossil fuel and biosphere CO 2 exchanges that might be obtained by using an atmospheric inverse modeling system driven by the combination of ground-based observations of radiocarbon and total CO 2, together with column-mean CO 2 observations from NASA's Orbiting Carbon Observatory (OCO-2). The work includes an initial examination of statistical uncertainties in prior models for CO 2 exchange, in radiocarbon-based fossil fuel CO 2 measurements, in OCO-2 measurements, and in a regional atmospheric transport modeling system. Using these nominal assumptions for measurement and model uncertainties, we find that flask measurements of radiocarbon and total CO 2 at 10 towers can be used to distinguish between different fossil fuel emission data products for major urban regions of California. We then show that the combination of flask and OCO-2 observations yields posterior uncertainties in monthly-mean fossil fuel emissions of ~5–10%, levels likely useful for policy relevant evaluation of bottom-up fossil fuel emission estimates. Similarly, we find that inversions yield uncertainties in monthly biosphere CO 2 exchange of ~6%–12%, depending on season, providing useful information on net carbon uptake in California's forests and agricultural lands. Finally, initial sensitivity analysis suggests thatmore » obtaining the above results requires control of systematic biases below approximately 0.5 ppm, placing requirements on accuracy of the atmospheric measurements, background subtraction, and atmospheric transport modeling.« less
ORCiD logo [1] ; ORCiD logo [2] ;  [3] ; ORCiD logo [1] ; ORCiD logo [1] ; ORCiD logo [4] ;  [5] ;  [6] ; ORCiD logo [7] ; ORCiD logo [8] ; ORCiD logo [3]
  1. Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
  2. California Inst. of Technology (CalTech), Pasadena, CA (United States)
  3. Imperial College London, London (United Kingdom)
  4. Jet Propulsion Lab., Pasadena, CA (United States)
  5. Univ. of California, San Diego, La Jolla, CA (United States)
  6. Colorado State Univ., Fort Collins, CO (United States)
  7. Arizona State Univ., Tucson, AZ (United States)
  8. NASA Goddard Space Flight Center (GSFC), Greenbelt, MD (United States); Univ. Space Research Assoc., Columbia, MD (United States)
Publication Date:
Report Number(s):
Journal ID: ISSN 2169-897X; ir:1007266
Grant/Contract Number:
Accepted Manuscript
Journal Name:
Journal of Geophysical Research: Atmospheres
Additional Journal Information:
Journal Volume: 122; Journal Issue: 6; Journal ID: ISSN 2169-897X
American Geophysical Union
Research Org:
Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
Sponsoring Org:
Energy Analysis & Environmental Impacts; USDOE
Country of Publication:
United States
58 GEOSCIENCES; 54 ENVIRONMENTAL SCIENCES; fossil fuel; biosphere; emissions; carbon dioxide; simulation; inversion
OSTI Identifier:
Alternate Identifier(s):
OSTI ID: 1402389