@article{fdi:010060529,
  title = {{N}atural land carbon dioxide exchanges in the {ECMWF} integrated forecasting system : implementation and offline validation},
  author = {{B}oussetta, {S}. and {B}alsamo, {G}. and {B}eljaars, {A}. and {P}anareda, {A}. {A}. and {C}alvet, {J}. {C}. and {J}acobs, {C}. and van den {H}urk, {B}. and {V}iterbo, {P}. and {L}afont, {S}. and {D}utra, {E}. and {J}arlan, {L}ionel and {B}alzarolo, {M}. and {P}apale, {D}. and van der {W}erf, {G}.},
  editor = {},
  language = {{ENG}},
  abstract = {{T}he {E}uropean {C}entre for {M}edium-{R}ange {W}eather {F}orecasts land surface model has been extended to include a carbon dioxide module. {T}his relates photosynthesis to radiation, atmospheric carbon dioxide ({CO}2) concentration, soil moisture, and temperature. {F}urthermore, it has the option of deriving a canopy resistance from photosynthesis and providing it as a stomatal control to the transpiration formulation. {E}cosystem respiration is based on empirical relations dependent on temperature, soil moisture, snow depth, and land use. {T}he {CO}2 model is designed for the numerical weather prediction ({NWP}) environment where it benefits from good quality meteorological input (i.e., radiation, temperature, and soil moisture). {T}his paper describes the {CO}2 model formulation and the way it is optimized making use of off-line simulations for a full year of tower observations at 34 sites. {T}he model is then evaluated against the same observations for a different year. {A} correlation coefficient of 0.65 is obtained between model simulations and observations based on 10 day averaged {CO}2 fluxes. {F}or sensible and latent heat fluxes there is a correlation coefficient of 0.80. {T}o study the impact on atmospheric {CO}2, coupled integrations are performed for the 2003 to 2008 period. {T}he global atmospheric growth is well reproduced. {T}he simulated interannual variability is shown to reproduce the observationally based estimates with a correlation coefficient of 0.70. {T}he main conclusions are (i) the simple carbon dioxide model is highly suitable for the numerical weather prediction environment where environmental factors are controlled by data assimilation, (ii) the use of a carbon dioxide model for stomatal control has a positive impact on evapotranspiration, and (iii) even using a climatological leaf area index, the interannual variability of the global atmospheric {CO}2 budget is well reproduced due to the interannual variability in the meteorological forcing (i.e., radiation, precipitation, temperature, humidity, and soil moisture) despite the simplified or missing processes. {T}his highlights the importance of meteorological forcing but also cautions the use of such a simple model for process attribution.},
  keywords = {{L}atent heat ; {S}ensible heat ; {N}et ecosystem exchange ; {C}anopy resistance ; {A}tmospheric {CO}2 growth},
  booktitle = {},
  journal = {{J}ournal of {G}eophysical {R}esearch. {A}tmospheres},
  volume = {118},
  numero = {12},
  pages = {5923--5946},
  ISSN = {2169-897{X}},
  year = {2013},
  DOI = {10.1002/jgrd.50488},
  URL = {https://www.documentation.ird.fr/hor/fdi:010060529},
}