Atmospheric Chemistry and Physics www.atmos-chem-phys.net 1680-7316 1680-7324 8 22 2008 10.5194/acp-8-6587-2008 http://www.atmos-chem-phys.net/8/6587/2008/ http://www.atmos-chem-phys.net/8/6587/2008/acp-8-6587-2008.html http://www.atmos-chem-phys.net/8/6587/2008/acp-8-6587-2008.pdf 6587 6596 2008-11-17 Modelling representation errors of atmospheric CO₂ mixing ratios at a regional scale L. F. Tolk lieselotte.tolk@falw.vu.nl A. G. C. A. Meesters A. J. Dolman W. Peters VU University Amsterdam, Amsterdam, The Netherlands Wageningen University and Research Centre, Wageningen, The Netherlands Inverse modelling of carbon sources and sinks requires an accurate quality estimate of the modelling framework to obtain a realistic estimate of the inferred fluxes and their uncertainties. So-called "representation errors" result from our inability to correctly represent point observations with simulated average values of model grid cells. They may add substantial uncertainty to the interpretation of atmospheric CO₂ mixing ratio data. We simulated detailed variations in the CO₂ mixing ratios with a high resolution (2 km) mesoscale model (RAMS) to estimate the representation errors introduced at larger model grid sizes of 10–100 km. We found that meteorology is the main driver of representation errors in our study causing spatial and temporal variations in the error estimate. Within the nocturnal boundary layer, the representation errors are relatively large and mainly caused by unresolved topography at lower model resolutions. During the day, convective structures, mesoscale circulations, and surface CO₂ flux variability were found to be the main sources of representation errors. Interpreting observations near a mesoscale circulation as representative for air with the correct footprint relative to the front can reduce the representation error substantially. The remaining representation error is 0.5–1.5 ppm at 20–100 km resolution. Ahmadov, R., Gerbig, C., Kretschmer, R., Koerner, S., Neininger, B., Dolman, A., and Sarrat, C.: Mesoscale covariance of transport and CO₂ fluxes: Evidence from observations and simulations using the WRF-VPRM coupled atmosphere-biosphere model, J. Geophys. Res., 112, D22107, doi:10.1029/2007JD008552, 2007. Ara\'ujo, A. C., Kruijt, B., Nobre, A. D., Dolman, A. J., Waterloo, M. J., Moors, E. J., and De Souza, J.: Noctural accumulation of CO₂ underneath a tropical forest canopy along a topographical gradient, Ecol. Appl., in press, 2008. Aubinet, M., Heinesch, B., and Yernaux, M.: Horizontal and vertical CO₂ advection in a sloping forest, Bound.-Lay. Meteorol., 108, 397–417, 2003. Baker, D. F., Law, R. M., Gurney, K. R., Rayner, P., Peylin, P., Denning, A. S., Bousquet, P., Bruhwiler, L., Chen, Y. H., Ciais, P., Fung, I. Y., Heimann, M., John, J., Maki, T., Maksyutov, S., Masarie, K., Prather, M., Pak, B., Taguchi, S., and Zhu, Z.: Transcom 3 inversion intercomparison: Impact of transport model errors on the interannual variability of regional CO₂ fluxes, 1988–2003, Global Biogeochem. Cy., 20, GB1002, doi:10.1029/2004GB002439, 2006. Bousquet, P., Ciais, P., Peylin, P., Ramonet, M., and Monfray, P.: Inverse modeling of annual atmospheric CO₂ sources and sinks 1. Method and control inversion, J. Geophys. Res., 104(D21), 26 161–26 178, 1999. Carouge, C.: Vers une estimation des flux de CO₂ europeen, PhD Thesis, 2006. Corbin, K. D., Denning, A. S., Lu, L., Wang, J. W., and Baker, I. T.: Possible representation errors in inversions of satellite CO₂ retrievals, J. Geophys. Res., 113, D02301, doi:10.1029/2007JD008716, 2008. Denning, A. S., Randall, D. A., Collatz, G. J., and Sellers, P. J.: Simulations of terrestrial carbon metabolism and atmospheric CO₂ in a general circulation model: 2. Simulated CO₂ concentrations, Tellus B, 48, 543–567, 1996. Denning, A. S., Nicholls, M., Prihodko, L., Baker, I., Vidale, P. L., Davis, K., and Bakwin, P.: Simulated variations in atmospheric CO₂ over a Wisconsin forest using a coupled ecosystem-atmosphere model, Global Change Biol., 9, 1241–1250, 2003. Dolman, A. J., Noilhan, J., Durand, P., Sarrat, C., Brut, A., Piguet, B., Butet, A., Jarosz, N., Brunet, Y., Loustau, D., Lamaud, E., Tolk, L., Ronda, R., Miglietta, F., Gioli, B., Magliulo, V., Esposito, M., Gerbig, C., Korner, S., Glademard, R., Ramonet, M., Ciais, P., Neininger, B., Hutjes, R. W. A., Elbers, J. A., Macatangay, R., Schrems, O., Perez-Landa, G., Sanz, M. J., Scholz, Y., Facon, G., Ceschia, E., and Beziat, P.: The Carboeurope regional experiment strategy, B. Am. Meteorol. Soc., 87, 1367–1379, 2006. Eugster, W. and Siegrist, F.: The influence of nocturnal CO₂ advection on CO₂ flux measurements, Basic Appl. Ecol., 1, 177–188, 2000. Fan, S., Gloor, M., Mahlman, J., Pacala, S., Sarmiento, J., Takahashi, T., and Tans, P.: A large terrestrial carbon sink in North America implied by atmospheric and oceanic carbon dioxide data and models, Science, 282, 442–446, 1998. Farquhar, G. D., Caemmerer, S. V., and Berry, J. A.: A biochemical-model of photosynthetic CO₂ assimilation in leaves of C-3 species, Planta, 149, 78–90, 1980. Geels, C., Gloor, M., Ciais, P., Bousquet, P., Peylin, P., Vermeulen, A. T., Dargaville, R., Aalto, T., Brandt, J., Christensen, J. H., Frohn, L. M., Haszpra, L., Karstens, U., Rödenbeck, C., Ramonet, M., Carboni, G., and Santaguida, R.: Comparing atmospheric transport models for future regional inversions over Europe – Part~1: mapping the atmospheric CO₂ signals, Atmos. Chem. Phys., 7, 3461–3479, 2007. Gerbig, C., Lin, J. C., Wofsy, S. C., Daube, B. C., Andrews, A. E., Stephens, B. B., Bakwin, P. S., and Grainger, C. A.: Toward constraining regional-scale fluxes of CO₂ with atmospheric observations over a continent: 1. Observed spatial variability from airborne platforms, J. Geophys. Res., 108(D24), 4756, doi:10.1029/2002JD003018, 2003. Gerbig, C., Lin, J. C., Wofsy, S. C., Daube, B. C., Andrews, A. E., Stephens, B. B., Bakwin, P. S., and Grainger, C. A.: Toward constraining regional-scale fluxes of CO₂ with atmospheric observations over a continent: 2. Analysis of COBRA data using a receptor-oriented framework, J. Geophys. Res., 108(D24), 4757, doi:10.1029/2003JD003770, 2003. Goulden, M. L., Miller, S. D., and da Rocha, H. R.: Nocturnal cold air drainage and pooling in a tropical forest, J. Geophys. Res., 111, D08S04, doi:10.1029/2005JD006037, 2006. Gurney, K. R., Law, R. M., Denning, A. S., Rayner, P. J., Baker, D., Bousquet, P., Bruhwiler, L., Chen, Y. H., Ciais, P., Fan, S., Fung, I. Y., Gloor, M., Heimann, M., Higuchi, K., John, J., Maki, T., Maksyutov, S., Masarie, K., Peylin, P., Prather, M., Pak, B. C., Randerson, J., Sarmiento, J., Taguchi, S., Takahashi, T., and Yuen, C. W.: Towards robust regional estimates of CO₂ sources and sinks using atmospheric transport models, Nature, 415, 626–630, 2002. Houweling, S., Dentener, F., Lelieveld, J., Walter, B., and Dlugokencky, E.: The modeling of tropospheric methane: How well can point measurements be reproduced by a global model?, J. Geophys. Res.-Atmos., 105, 8981–9002, 2000. Kaminski, T., Rayner, P. J., Heimann, M., and Enting, I. G.: On aggregation errors in atmospheric transport inversions, J. Geophys. Res.-Atmos., 106, 4703–4715, 2001. Karstens, U., Gloor, M., Heimann, M., and Rodenbeck, C.: Insights from simulations with high-resolution transport and process models on sampling of the atmosphere for constraining midlatitude land carbon sinks, J. Geophys. Res., 111, D12301, doi:10.1029/2005JD006278, 2006. Lauvaux, T., Uliasz, M., Sarrat, C., Chevallier, F., Bousquet, P., Lac, C., Davis, K. J., Ciais, P., Denning, A. S., and Rayner, P. J.: Mesoscale inversion: first results from the CERES campaign with synthetic data, Atmos. Chem. Phys., 8, 3459–3471, 2008. Lin, J. C., Gerbig, C., Daube, B. C., Wofsy, S. C., Andrews, A. E., Vay, S. A., and Anderson, B. E.: An empirical analysis of the spatial variability of atmospheric CO₂: Implications for inverse analyses and space-borne sensors, Geophys. Res. Lett., 31, L23104, doi:10.1029/2004GL020957, 2004. Medvigy, D., Moorcroft, P. R., Avissar, R., and Walko, R. L.: Mass conservation and atmospheric dynamics in the regional atmospheric modeling system (RAMS), Environ. Fluid Mech., 5, 109–134, 2005. Meesters, A. G. C. A., Tolk, L. F., and Dolman, A. J.: Mass conservation above slopes in the regional atmospheric modelling system (RAMS), Environ. Fluid Mech., 8, 239–248, 2008. Nicholls, M. E., Denning, A. S., Prihodko, L., Vidale, P. L., Baker, I., Davis, K., and Bakwin, P.: A multiple-scale simulation of variations in atmospheric carbon dioxide using a coupled biosphere-atmospheric model, J. Geophys. Res., 109, D18117, doi:10.1029/2003JD004482, 2004. Pérez-Landa, G., Ciais, P., Gangoiti, G., Palau, J. L., Carrara, A., Gioli, B., Miglietta, F., Schumacher, M., Millán, M. M., and Sanz, M. J.: Mesoscale circulations over complex terrain in the Valencia coastal region, Spain – Part 2: Modeling CO₂ transport using idealized surface fluxes, Atmos. Chem. Phys., 7, 1851–1868, 2007. Peters, W., Krol, M. C., Dlugokencky, E. J., Dentener, F. J., Bergamaschi, P., Dutton, G., von Velthoven, P., Miller, J. B., Bruhwiler, L., and Tans, P. P.: Toward regional-scale modeling using the two-way nested global model TM5: Characterization of transport using SF$_6$, J. Geophys. Res., 109, D19314, doi:10.1029/2004JD005020, 2004. Peters, W., Jacobson, A. R., Sweeney, C., Andrews, A. E., Conway, T. J., Masarie, K., Miller, J., Bruhwiler, L. M. P., Petron, G., and Hirsch, A. I., Worthy, D. E. J., van der Werf, G. R., Randerson, J. T., Wennberg, P. O., Krol, M. C., and Tans, P. P.: An atmospheric perspective on North American carbon dioxide exchange: Carbontracker, P. Natl. Acad. Sci. USA, 104, 18 925–18 930, 2007. Pielke, R. A., Cotton, W. R., Walko, R. L., Tremback, C. J., Lyons, W. A., Grasso, L. D., Nicholls, M. E., Moran, M. D., Wesley, D. A., Lee, T. J., and Copeland, J. H.: A comprehensive meteorological modeling system – RAMS, Meteorol. Atmos. Phys., 49, 69–91, 1992. Rödenbeck, C., Houweling, S., Gloor, M., and Heimann, M.: CO₂ flux history 1982–2001 inferred from atmospheric data using a global inversion of atmospheric transport, Atmos. Chem. Phys., 3, 1919–1964, 2003. Sarrat, C., Noilhan, J., Lacarrere, P., Donier, S., Lac, C., Calvet, J. C., Dolman, A. J., Gerbig, C., Neininger, B., Ciais, P., Paris, J. D., Boumard, F., Ramonet, M., and Butet, A.: Atmospheric CO₂ modeling at the regional scale: Application to the carboeurope regional experiment, J. Geophys. Res., 112, D12105, doi:10.1029/2006JD008107, 2007. Sarrat, C., Noilhan, J., Dolman, A. J., Gerbig, C., Ahmadov, R., Tolk, L. F., Meesters, A. G. C. A., Hutjes, R. W. A., Ter Maat, H. W., Pérez-Landa, G., and Donier, S.: Atmospheric CO₂ modeling at the regional scale: an intercomparison of 5 meso-scale atmospheric models, Biogeosciences, 4, 1115–1126, 2007. Schmidt, M., Graul, R., Sartorius, H., and Levin, I.: The Schauinsland CO₂ record: 30 years of continental observations and their implications for the variability of the European CO₂ budget, J. Geophys. Res., 108(D19), 4619, doi:10.1029/2002JD003085, 2003. Sellers, P. J., Los, S. O., Tucker, C. J., Justice, C. O., Dazlich, D. A., Collatz, G. J., and Randall, D. A.: A revised land surface parameterization (SiB2) for atmospheric GCMs 2. The generation of global fields of terrestrial biophysical parameters from satellite data, J. Climate, 9, 706–737, 1996. Stephens, B. B., Gurney, K. R., Tans, P. P., Sweeney, C., Peters, W., Bruhwiler, L., Ciais, P., Ramonet, M., Bousquet, P., Nakazawa, T., Aoki, S., Machida, T., Inoue, G., Vinnichenko, N., Lloyd, J., Jordan, A., Heimann, M., Shibistova, O., Langenfelds, R. L., Steele, L. P., Francey, R. J., and Denning, A. S.: Weak northern and strong tropical land carbon uptake from vertical profiles of atmospheric CO₂, Science, 316, 1732–1735, 2007. Van der Molen, M. K. and Dolman, A. J.: Regional carbon fluxes and the effect of topography on the variability of atmospheric CO₂, J. Geophys. Res., 112, D01104, doi:10.1029/2006JD007649, 2007. Van Dijk, A. I. J. M. and Dolman, A. J.: Estimates of CO₂ uptake and release among european forests based on eddy covariance data, Global Change Biol., 10, 1445–1459, 2004. Walko, R. L., Band, L. E., Baron, J., Kittel, T. G. F., Lammers, R., Lee, T. J., Ojima, D., Pielke, R. A., Taylor, C., Tague, C., Tremback, C. J., and Vidale, P. L.: Coupled atmosphere-biophysics-hydrology models for environmental modeling, J. Appl. Meteorol., 39, 931–944, 2000. Wullschleger, S. D.: Biochemical limitations to carbon assimilation in C₃ plants -a retrospective analysis of the A/C$_i$ curves from 109 species, J. Exp. Bot., 44, 907–920, 1993. Yang, Z., Washenfelder, R. A., Keppel-Aleks, G., Krakauer, N. Y., Randerson, J. T., Tans, P. P., Sweeney, C., and Wennberg, P. O.: New constraints on northern hemisphere growing season net flux, Geophys. Res. Lett., 34, L12807, doi:10.1029/2007GL029742, 2007. Zupanski, D., Denning, A. S., Uliasz, M., Zupanski, M., Schuh, A. E., Rayner, P. J., Peters, W., and Corbin, K. D.: Carbon flux bias estimation employing maximum likelihood ensemble filter (MLEF), J. Geophys. Res., 112, D17107, doi:10.1029/2006JD008371, 2007.