The browser you are using is not supported by this website. All versions of Internet Explorer are no longer supported, either by us or Microsoft (read more here: https://www.microsoft.com/en-us/microsoft-365/windows/end-of-ie-support).

Please use a modern browser to fully experience our website, such as the newest versions of Edge, Chrome, Firefox or Safari etc.

Portrait of Alex Vermeulen

Alex Vermeulen

Manager

Portrait of Alex Vermeulen

A European summertime CO2 biogenic flux inversion at mesoscale from continuous in situ mixing ratio measurements

Author

  • Gregoire Broquet
  • Frederic Chevallier
  • Peter Rayner
  • Celine Aulagnier
  • Isabelle Pison
  • Michel Ramonet
  • Martina Schmidt
  • Alex Vermeulen
  • Philippe Ciais

Summary, in English

A regional variational inverse modeling system for the estimation of European biogenic CO2 fluxes is presented. This system is based on a 50 km horizontal resolution configuration of a mesoscale atmospheric transport model and on the adjoint of its tracer transport code. It exploits hourly CO2 in situ data from 15 CarboEurope-Integrated Project stations. Particular attention in the inversion setup is paid to characterizing the transport model error and to selecting the observations to be assimilated as a function of this error. Comparisons between simulations and data of CO2 and Rn-222 concentrations indicate that the model errors should have a standard deviation which is less than 7 ppm when simulating the hourly variability of CO2 at low altitude during the afternoon and evening or at high altitude at night. Synthetic data are used to estimate the uncertainty reduction for the fluxes using this inverse modeling system. The improvement brought by the inversion to the prior estimate of the fluxes for both the mean diurnal cycle and the monthly to synoptic variability in the fluxes and associated mixing ratios are checked against independent atmospheric data and eddy covariance flux measurements. Inverse modeling is conducted for summers 2002-2007 which should reduce the uncertainty in the biogenic fluxes by similar to 60% during this period. The trend in the mean flux corrections between June and September is to increase the uptake of CO2 by similar to 12 gCm(-2). Corrections at higher resolution are also diagnosed that reveal some limitations of the underlying prior model of the terrestrial biosphere.

Publishing year

2011

Language

English

Pages

1-22

Publication/Series

Journal of Geophysical Research: Atmospheres

Volume

116

Document type

Journal article

Publisher

Wiley-Blackwell

Topic

  • Physical Geography

Status

Published

ISBN/ISSN/Other

  • ISSN: 2169-8996
  • Article number D23303