Optimal representation of source-sink fluxes for mesoscale carbon dioxide inversion with synthetic data

Lin Wu, Marc Bocquet, Thomas Claude Yves Lauvaux, Frédéric Chevallier, Peter Rayner, Kenneth James Davis

Research output: Contribution to journalArticle

36 Citations (Scopus)

Abstract

The inversion of CO2 surface fluxes from atmospheric concentration measurements involves discretizing the flux domain in time and space. The resolution choice is usually guided by technical considerations despite its impact on the solution to the inversion problem. In our previous studies, a Bayesian formalism has recently been introduced to describe the discretization of the parameter space over a large dictionary of adaptive multiscale grids. In this paper, we exploit this new framework to construct optimal space-time representations of carbon fluxes for mesoscale inversions. Inversions are performed using synthetic continuous hourly CO2 concentration data in the context of the Ring 2 experiment in support of the North American Carbon Program Mid Continent Intensive (MCI). Compared with the regular grid at finest scale, optimal representations can have similar inversion performance with far fewer grid cells. These optimal representations are obtained by maximizing the number of degrees of freedom for the signal (DFS) that measures the information gain from observations to resolve the unknown fluxes. Consequently information from observations can be better propagated within the domain through these optimal representations. For the Ring 2 network of eight towers, in most cases, the DFS value is relatively small compared to the number of observations d (DFS/d < 20%). In this multiscale setting, scale-dependent aggregation errors are identified and explicitly formulated for more reliable inversions. It is recommended that the aggregation errors should be taken into account, especially when the correlations in the errors of a priori fluxes are physically unrealistic. The optimal multiscale grids allow to adaptively mitigate the aggregation errors.

Original languageEnglish (US)
Article numberD21304
JournalJournal of Geophysical Research Atmospheres
Volume116
Issue number21
DOIs
StatePublished - Jan 1 2011

Fingerprint

sinks
Carbon Dioxide
carbon dioxide
inversions
Fluxes
carbon
grids
Agglomeration
space and time
degrees of freedom
Carbon
Glossaries
dictionaries
rings
Towers
towers
cells
surface flux
continents
carbon flux

All Science Journal Classification (ASJC) codes

  • Geophysics
  • Forestry
  • Oceanography
  • Aquatic Science
  • Ecology
  • Water Science and Technology
  • Soil Science
  • Geochemistry and Petrology
  • Earth-Surface Processes
  • Atmospheric Science
  • Earth and Planetary Sciences (miscellaneous)
  • Space and Planetary Science
  • Palaeontology

Cite this

Wu, Lin ; Bocquet, Marc ; Lauvaux, Thomas Claude Yves ; Chevallier, Frédéric ; Rayner, Peter ; Davis, Kenneth James. / Optimal representation of source-sink fluxes for mesoscale carbon dioxide inversion with synthetic data. In: Journal of Geophysical Research Atmospheres. 2011 ; Vol. 116, No. 21.
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Optimal representation of source-sink fluxes for mesoscale carbon dioxide inversion with synthetic data. / Wu, Lin; Bocquet, Marc; Lauvaux, Thomas Claude Yves; Chevallier, Frédéric; Rayner, Peter; Davis, Kenneth James.

In: Journal of Geophysical Research Atmospheres, Vol. 116, No. 21, D21304, 01.01.2011.

Research output: Contribution to journalArticle

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