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Atmos. Chem. Phys. Discuss., 9, 23187-23210, 2009
www.atmos-chem-phys-discuss.net/9/23187/2009/ doi:10.5194/acpd-9-23187-2009 © Author(s) 2009. This work is distributed under the Creative Commons Attribution 3.0 License. |
Technical Note: A new coupled system for global-to-regional downscaling of CO2 concentration estimation
Max-Planck Institute for Biogeochemistry, Hans-Knoell Str. 10, 07745 Jena, Germany
Abstract. We introduce a global-to-regional nesting scheme for atmospheric transport models that are used for simulating concentrations of green house gases from globally distributed surface fluxes. The coupled system of the regional Stochastic Time-Inverted Lagrangian Transport (STILT) model and the global atmospheric transport model (TM3) is designed to resolve atmospheric trace gas concentrations at high temporal and spatial resolutions in a specified domain e.g. for regional inverse applications. The nesting technique used for the coupling is based on a decomposition of the atmospheric concentration signal into a far-field and a near-field contribution that allows global and regional models being of different type, i.e. Eulerian (grid) and Lagrangian (trajectory). For illustrating the performance of the coupled TM3-STILT system we compare simulated mixing ratios of carbon dioxide with available observations at 10 sites in Europe. For all chosen sites the TM3-STILT provided higher correlations between the modelled and the measured time series than the TM3 global model. The autocorrelation analysis showed that in contrast to the global model TM3-STILT model is capable to represent the variability of the measured tracer concentrations.
Citation: Trusilova, K., Rödenbeck, C., Gerbig, C., and Heimann, M.: Technical Note: A new coupled system for global-to-regional downscaling of CO2 concentration estimation, Atmos. Chem. Phys. Discuss., 9, 23187-23210, doi:10.5194/acpd-9-23187-2009, 2009.