References

ACPD

Atmospheric Chemistry and Physics Discussions

ACPD

1680-7375

Copernicus GmbH

Göttingen, Germany

10.5194/acpd-11-11455-2011

Using boundary layer equilibrium to reduce uncertainties in transport models and CO2 flux inversions

Williams

I. N.

¹ Riley

W. J.

² Torn

M. S.

² Berry

J. A.

³ Biraud

S. C.

Department of Geophysical Sciences, University of Chicago, Chicago, IL, USA

Lawrence Berkeley National Laboratory, Earth Sciences Division, Berkeley, CA, USA

Carnegie Institution of Washington, Stanford, CA, USA

13 04 2011

11 4 11455 11495

This is an open-access article ditributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

This article is available from http://www.atmos-chem-phys-discuss.net/11/11455/2011/acpd-11-11455-2011.html

The full text article is available as a PDF file from http://www.atmos-chem-phys-discuss.net/11/11455/2011/acpd-11-11455-2011.pdf

This paper reexamines evidence for previously hypothesized errors in atmospheric transport models and CO2 flux inversions by evaluating the diagnostics used to infer vertical mixing rates from observations. Several conventional mixing diagnostics are compared to analyzed mixing using data from the US Southern Great Plains Atmospheric Radiation Measurement Climate Research Facility, the CarbonTracker data assimilation system based on Transport Model version 5 (TM5), and atmospheric reanalyses. The results demonstrate that previous diagnostics based on boundary layer depth and vertical concentration gradients are unreliable indicators of vertical mixing. Vertical mixing rates are anti-correlated with boundary layer depth at some sites, diminishing in summer when the boundary layer is deepest. Vertical CO2 gradients between the boundary layer and free-troposphere are strongly affected by seasonal surface fluxes and therefore do not accurately reflect vertical mixing rates. The finite timescale over which vertical tracer gradients relax toward equilibrium is proposed as an improved mixing diagnostic, which can be applied to observations and model simulations of CO2 or other conserved boundary layer tracers with surface sources and sinks. This diagnostic does not require dynamical variables from the transport models, and is independent of possible systematic biases in prior- and post-inversion seasonal surface fluxes. Results indicate that observations frequently cited as evidence for systematic biases in atmospheric transport models are insufficient to prove that such biases exist. Some previously hypothesized transport model biases, if found and corrected, could cause inverse estimates to further diverge from land-based estimates.

References 1

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 \chemCO_2 fluxes, 1988–2003, Global Biogeochem. Cy., 20, doi:10.1029/2004GB002439, 2006.

Bakwin,~P S., Tans,~P P., Zhao,~C L., Ussler,~W., and Quesnell,~E.: Measurements of carbon-dioxide on a~very tall tower, Tellus~B, 47, 535–549, 1995.

Bakwin,~P S., Davis,~K J., Yi,~C., Wofsy,~S C., Munger,~J W., Haszpra,~L., and Barcza,~Z.: Regional carbon dioxide fluxes from mixing ratio data, Tellus~B, 56, 301–311, 2004.

Bousquet,~P., Peylin,~P., Ciais,~P., Le~Quere,~C., Friedlingstein,~P., and Tans,~P P.: Regional changes in carbon dioxide fluxes of land and oceans since 1980, Science, 290, 1342–1346, 2000.

Chatfield,~C.: The Analysis of Time Series, Chapman & Hall, New York, USA, 2004.

Chen,~B Z., Chen,~J M., Liu,~J., Chan,~D., Higuchi,~K., and Shashkov,~A.: A~vertical diffusion scheme to estimate the atmospheric rectifier effect, J Geophys. Res.-Atmos., D04306, doi:10.1029/2003JD003925, 109, 2004.

Chou,~W W., Wofsy,~S C., Harriss,~R C., Lin,~J C., Gerbig,~C., and Sachse,~G W.: Net fluxes of \chemCO_2 in Amazonia derived from aircraft observations, J Geophys. Res.-Atmos., 107, D04614, doi:10.1029/2001JD001295, 2002.

Conway,~T J., Tans,~P P., Waterman,~L S., and Thoning,~K W.: Evidence for interannual variability of the carbon-cycle from the National Oceanic and Atmospheric Administration Climate Monitoring and Diagnostics Laboratory Global Air-Sampling Network, J Geophys. Res.-Atmos., 99, 22831–22855, 1994.

Cooley,~H S., Riley,~W J., Torn,~M S., and He,~Y.: Impact of agricultural practice on regional climate in a~coupled land surface mesoscale model, J Geophys. Res.-Atmos., 110, D03113, doi:10.1029/2004jd005160, 2005.

Dargaville,~R J., Doney,~S C., and Fung,~I Y.: Inter-annual variability in the interhemispheric atmospheric \chemCO_2 gradient: contributions from transport and the seasonal rectifier, Tellus~B, 55, 711–722, 2003.

Davis,~K J., Bakwin,~P S., Yi,~C X., Berger,~B W., Zhao,~C L., Teclaw,~R M., and Isebrands,~J G.: The annual cycles of \chemCO_2 and \chemH_2O exchange over a~northern mixed forest as observed from a~very tall tower, Glob. Change Biol., 9, 1278–1293, 2003.

Denman, K. L., Brasseur, G., Chidthaisong, A., Ciais, P., Cox, P. M., Dickinson, R. E., Hauglustaine, D., Heinze, C., Holland, E., Jacob, D., Lohmann, U., Ramachandran, S., da Silva Dias, P. L., Wofsy, S. C., and Zhang, X., Couplings between changes in the climate system and biogeochemistry, in: Climate change 2007: The physical science basis. Contribution of working group I to the fourth assessment report of the intergovernmental panel on climate change, edited by: Solomon, S., Qin, D., Manning, M., Chen, Z., Marquis, M., Averyt, K. B., Tignor, M., and Miller, H. L., Cambridge University Press, Cambridge, New York, USA, 2007.

Denning,~A S., Fung,~I Y., and Randall,~D.: Latitudinal gradient of atmospheric \chemCO_2 due to seasonal exchange with land biota, Nature, 376, 240–243, 1995.

Denning,~A S., Holzer,~M., Gurney,~K R., Heimann,~M., Law,~R M., Rayner,~P J., Fung,~I Y., Fan,~S M., Taguchi,~S., Friedlingstein,~P., Balkanski,~Y., Taylor,~J., Maiss,~M., and Levin,~I.: Three-dimensional transport and concentration of SF6 – a~model intercomparison study (TransCom~2), Tellus~B, 51, 266–297, 1999.

Denning,~A S., Zhang,~N., Yi,~C X., Branson,~M., Davis,~K., Kleist,~J., and Bakwin,~P.: Evaluation of modeled atmospheric boundary layer depth at the WLEF tower, Agr. Forest Meteor., 148, 206–215, 2008.

Emanuel,~K.: Atmospheric Convection, Oxford University Press, New York, USA, 1994.

Erickson,~D J., Mills,~R T., Gregg,~J., Blasing,~T J., Hoffman,~F M., Andres,~R J., Devries,~M., Zhu,~Z., and Kawa,~S R.: An estimate of monthly global emissions of anthropogenic \chemCO_2: Impact on the seasonal cycle of atmospheric \chemCO_2, J Geophys. Res.-Biogeo., 113, G01023, doi:10.1029/2007jg000435, 2008.

Fischer,~M L., Billesbach,~D P., Berry,~J A., Riley,~W J., and Torn,~M S.: Spatiotemporal variations in growing season exchanges of \chemCO_2, \chemH_2O, and sensible heat in agricultural fields of the Southern Great Plains, Earth Interact., 11(17), 1–21, 2007.

Friedlingstein,~P., Cox,~P., Betts,~R., Bopp,~L., Von~Bloh,~W., Brovkin,~V., Cadule,~P., Doney,~S., Eby,~M., Fung,~I., Bala,~G., John,~J., Jones,~C., Joos,~F., Kato,~T., Kawamiya,~M., Knorr,~W., Lindsay,~K., Matthews,~H D., Raddatz,~T., Rayner,~P., Reick,~C., Roeckner,~E., Schnitzler,~K G., Schnur,~R., Strassmann,~K., Weaver,~A J., Yoshikawa,~C., and Zeng,~N.: Climate-carbon cycle feedback analysis: results from the (CMIP)-M-4 model intercomparison, J Climate, 19, 3337–3353, 2006.

Fung,~I., Prentice,~K., Matthews,~E., Lerner,~J., and Russell,~G.: 3-dimensional tracer model study of atmospheric \chemCO_2 – response to seasonal exchanges with the terrestrial biosphere, J Geophys. Res.-Oc. Atm., 88, 1281–1294, 1983.

Gloor,~M., Fan,~S M., Pacala,~S., Sarmiento,~J., and Ramonet,~M.: A~model-based evaluation of inversions of atmospheric transport, using annual mean mixing ratios, as a~tool to monitor fluxes of nonreactive trace substances like \chemCO_2 on a~continental scale, J Geophys. Res.-Atmos., 104, 14245–14260, 1999.

Gloor,~M., Dlugokencky,~E., Brenninkmeijer,~C., Horowitz,~L., Hurst,~D F., Dutton,~G., Crevoisier,~C., Machida,~T., and Tans,~P.: Three-dimensional SF6 data and tropospheric transport simulations: signals, modeling accuracy, and implications for inverse modeling, J Geophys. Res.-Atmos., 110, D10308, doi:10.1029/2004jd005373, 2007.

Guichard,~F., Petch,~J C., Redelsperger,~J L., Bechtold,~P., Chaboureau,~J P., Cheinet,~S., Grabowski,~W., Grenier,~H., Jones,~C G., Kohler,~M., Piriou,~J M., Tailleux,~R., and Tomasini,~M.: Modelling the diurnal cycle of deep precipitating convection over land with cloud-resolving models and single-column models, Q J. Roy. Meteor. Soc., 130, 3139–3172, 2004.

Gurney,~K R., Chen,~Y H., Maki,~T., Kawa,~S R., Andrews,~A., and Zhu,~Z X.: Sensitivity of atmospheric \chemCO_2 inversions to seasonal and interannual variations in fossil fuel emissions, J Geophys. Res.-Atmos., 110, D10308, doi:10.1029/2004jd005373, 2005.

Helliker,~B R., Berry,~J A., Betts,~A K., Bakwin,~P S., Davis,~K J., Denning,~A S., Ehleringer,~J R., Miller,~J B., Butler,~M P., and Ricciuto,~D M.: Estimates of net \chemCO_2 flux by application of equilibrium boundary layer concepts to \chemCO_2 and water vapor measurements from a~tall tower, J Geophys. Res.-Atmos., 109, D20106, doi:10.1029/2004JD004532, 2004.

Lawrence,~M G. and Salzmann,~M.: On interpreting studies of tracer transport by deep cumulus convection and its effects on atmospheric chemistry, Atmos. Chem. Phys., 8, 6037–6050, http://dx.doi.org/10.5194/acp-8-6037-2008doi:10.5194/acp-8-6037-2008, 2008.

Levy,~P E., Grelle,~A., Lindroth,~A., Molder,~M., Jarvis,~P G., Kruijt,~B., and Moncrieff,~J B.: Regional-scale \chemCO_2 fluxes over Central Sweden by a~boundary layer budget method, Agr. Forest Meteor., 98–9, 169–180, 1999.

Lloyd,~J., Francey,~R J., Mollicone,~D., Raupach,~M R., Sogachev,~A., Arneth,~A., Byers,~J N., Kelliher,~F M., Rebmann,~C., Valentini,~R., Wong,~S C., Bauer,~G., and Schulze,~E D.: Vertical profiles, boundary layer budgets, and regional flux estimates for \chemCO_2 and its \chem^13C/\chem^12C ratio and for water vapor above a~forest/bog mosaic in Central Siberia, Global Biogeochem. Cy., 15, 267–284, 2001.

North,~G R., Bell,~R E., and Hardin,~J W.: Fluctuation dissipation in a~general circulation model, Clim. Dynam., 8, 259–264, 1993.

Patra,~P K., Takigawa,~M., Dutton,~G S., Uhse,~K., Ishijima,~K., Lintner,~B R., Miyazaki,~K., and Elkins,~J W.: Transport mechanisms for synoptic, seasonal and interannual \chemSF_6 variations and \qutage of air in troposphere, Atmos. Chem. Phys., 9, 1209–1225, http://dx.doi.org/10.5194/acp-9-1209-2009doi:10.5194/acp-9-1209-2009, 2009.

Peters,~W., Jacobson,~A R., Sweeney,~C., Andrews,~A E., Conway,~T J., Masarie,~K., Miller,~J B., Bruhwiler,~L M P., Petron,~G., 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, 18925–18930, 2007.

Peylin,~P., Baker,~D., Sarmiento,~J., Ciais,~P., and Bousquet,~P.: Influence of transport uncertainty on annual mean and seasonal inversions of atmospheric \chemCO_2 data, J Geophys. Res.-Atmos., 107(D19), 4385, doi:10.1029/2001JD000857, 2002.

Raupach,~M R.: Vegetation-atmosphere interaction in homogeneous and heterogeneous terrain – some implications of mixed-layer dynamics, Vegetatio, 91, 105–120, 1991.

Raupach,~M R., Denmead,~O T., and Dunin,~F X.: Challenges in linking atmospheric \chemCO_2 concentrations to fluxes at local and regional scales, Aust J. Bot., 40, 697–716, 1992.

Raymond,~D J.: Boundary layer quasi-equilibrium (BLQ), in: The Physics and Parameterization of Moist Convection, edited by: Smith,~R K., Kluwer Academic Publishers, Dordrecht, The Netherlands, 1997.

Riley,~W J., Biraud,~S C., Torn,~M S., Fischer,~M L., Billesbach,~D P., and Berry,~J A.: Regional \chemCO_2 and latent heat surface fluxes in the Southern Great Plains: measurements, modeling, and scaling, J Geophys. Res.-Biogeo., 114, G04009, doi:10.1029/2009JG001003, 2009.

Rödenbeck,~C., Houweling,~S., Gloor,~M., and Heimann,~M.: \chemCO_2 flux history 1982–2001 inferred from atmospheric data using a global inversion of atmospheric transport, Atmos. Chem. Phys., 3, 1919–1964, http://dx.doi.org/10.5194/acp-3-1919-2003doi:10.5194/acp-3-1919-2003, 2003.

Saltzman,~B. and Irsch,~F E.: Note on the theory of topographically forced planetary waves in atmosphere, Mon. Weather Rev., 100, 441–444, 1972.

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 \chemCO_2, Science, 316, 1732–1735, 2007.

Styles,~J M., Lloyd,~J., Zolotoukhine,~D., Lawton,~K A., Tchebakova,~N., Francey,~R J., Arneth,~A., Salamakho,~D., Kolle,~O., and Schulze,~E D.: Estimates of regional surface carbon dioxide exchange and carbon and oxygen isotope discrimination during photosynthesis from concentration profiles in the atmospheric boundary layer, Tellus~B, 54, 768–783, 2002.

Wallace,~J M.: Diurnal-variations in precipitation and thunderstorm frequency over conterminous United-States, Mon. Weather Rev., 103, 406–419, 1975.

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.

Yi,~C., Davis,~K J., Bakwin,~P S., Denning,~A S., Zhang,~N., Desai,~A., Lin,~J C., and Gerbig,~C.: Observed covariance between ecosystem carbon exchange and atmospheric boundary layer dynamics at a~site in Northern Wisconsin, J Geophys. Res.-Atmos., D08302, doi:10.1029/2003JD004164, 109, 2004.

Yi,~C X., Davis,~K J., Berger,~B W., and Bakwin,~P S.: Long-term observations of the dynamics of the continental planetary boundary layer, J Atmos. Sci., 58, 1288–1299, 2001.