 |
| Titel |
Importance of fossil fuel emission uncertainties over Europe for CO2 modeling: model intercomparison |
| VerfasserIn |
P. Peylin, S. Houweling, M. C. Krol, U. Karstens, C. Rödenbeck, C. Geels, A. Vermeulen, B. Badawy, C. Aulagnier, T. Pregger, F. Delage, G. Pieterse, P. Ciais, M. Heimann |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
1680-7316
|
| Digitales Dokument |
URL |
| Erschienen |
In: Atmospheric Chemistry and Physics ; 11, no. 13 ; Nr. 11, no. 13 (2011-07-12), S.6607-6622 |
| Datensatznummer |
250009906
|
| Publikation (Nr.) |
 copernicus.org/acp-11-6607-2011.pdf |
|
|
|
|
|
| Zusammenfassung |
Inverse modeling techniques used to quantify surface carbon fluxes
commonly assume that the uncertainty of fossil fuel CO2 (FFCO2)
emissions is negligible and that intra-annual variations can be
neglected. To investigate these assumptions, we analyzed the
differences between four fossil fuel emission inventories with spatial and
temporal differences over Europe and their impact on the model
simulated CO2 concentration. Large temporal flux variations
characterize the hourly fields (~40 % and ~80 % for the
seasonal and diurnal cycles, peak-to-peak) and annual country totals
differ by 10 % on average and up to 40 % for some countries (i.e., the
Netherlands). These emissions have been prescribed to seven different
transport models, resulting in 28 different FFCO2 concentrations
fields.
The modeled FFCO2 concentration time series at surface sites using
time-varying emissions show larger seasonal cycles (+2 ppm at the
Hungarian tall tower (HUN)) and smaller diurnal cycles in summer (−1 ppm
at HUN) than when using constant emissions. The concentration
range spanned by all simulations varies between stations, and is
generally larger in winter (up to ~10 ppm peak-to-peak at HUN)
than in summer (~5 ppm). The contribution of transport model
differences to the simulated concentration std-dev is 2–3 times larger
than the contribution of emission differences only, at typical
European sites used in global inversions. These contributions to the
hourly (monthly) std-dev's amount to ~1.2 (0.8) ppm and ~0.4
(0.3) ppm for transport and emissions, respectively. First
comparisons of the modeled concentrations with 14C-based fossil
fuel CO2 observations show that the large transport differences
still hamper a quantitative evaluation/validation of the emission
inventories. Changes in the estimated monthly biosphere flux (Fbio)
over Europe, using two inverse modeling approaches, are relatively
small (less that 5 %) while changes in annual Fbio (up
to ~0.15 % GtC yr−1) are only slightly smaller than the differences in annual
emission totals and around 30 % of the mean European ecosystem carbon
sink. These results point to an urgent need to improve not only the
transport models but also the assumed spatial and temporal
distribution of fossil fuel emission inventories. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|