Published Date
Abstract
The interpretation of eddy covariance flux measurements over inhomogeneous surfaces depends largely on the footprint over which the fluxes are captured. Based on the Schuepp’s footprint model, the Gaussian distribution was introduced to take into account the lateral dispersion, and a simple analytical model was proposed to determine the footprint of eddy flux measurements. The model was validated at an eddy flux site in a tall forest in Changbai Mountain, northeast China, and it was demonstrated to give more detailed descriptions of spatial representativeness for CO2/H2O flux measurements. The proposed model was evaluated against a relatively complicated analytical footprint model, the FSAM model, and the two models showed reasonable consistency. This study pointed out that the usually used 0.01 isopleth of source weight function for outer-limit boundaries of source area integration may cause systematic underestimation of footprint dimensions, and a 0.001 isopleth was suggested for scalar flux footprint analysis.
References
For further details log on website :
http://link.springer.com/article/10.1007/s10310-014-0437-2
, Volume 20, Issue 1, pp 222-229
First online:
Title
Application of a simple model to estimate the footprint of CO2/H2O emission from tall forest
- Author
Abstract
The interpretation of eddy covariance flux measurements over inhomogeneous surfaces depends largely on the footprint over which the fluxes are captured. Based on the Schuepp’s footprint model, the Gaussian distribution was introduced to take into account the lateral dispersion, and a simple analytical model was proposed to determine the footprint of eddy flux measurements. The model was validated at an eddy flux site in a tall forest in Changbai Mountain, northeast China, and it was demonstrated to give more detailed descriptions of spatial representativeness for CO2/H2O flux measurements. The proposed model was evaluated against a relatively complicated analytical footprint model, the FSAM model, and the two models showed reasonable consistency. This study pointed out that the usually used 0.01 isopleth of source weight function for outer-limit boundaries of source area integration may cause systematic underestimation of footprint dimensions, and a 0.001 isopleth was suggested for scalar flux footprint analysis.
References
- Aubinet M, Chermanne B, Vandenhaute M, Longdoz B, Yernaux M, Laitat E (2001) Long term carbon dioxide exchange above a mixed forest in the Belgian Ardennes. Agric For Meteorol 108:293–315CrossRef
- Baldocchi DD (1997) Flux footprints within and over forest canopies. Bound-Layer Meteorol 85:273–292CrossRef
- Baldocchi DD, Falge E, Gu L, Olson R, Hollinger DY, Running SW, Anthoni P, Davis KJ, Evans R, Fuentes J, Goldstein A, Katul G, Law BE, Lee X, Malhi Y, Meyers TP, Munger JW, Oechel WC, Paw KT, Pilegaard UK, Schmid H, Valentini R, Verma S, Vesala T, Wilson KB, Wofsy SC (2001) FLUXNET: a new tool to study the temporal and spatial variability of ecosystem-scale carbon dioxide, water vapor, and energy flux densities. Bull Am Meteorol Soc 82:2415–2434CrossRef
- Businger JA (1986) Evaluation of the accuracy with which dry deposition can be measured with current micrometeorological technique. J Clim Appl Meteor 25:1100–1124CrossRef
- Dyer A (1974) A review of flux-profile relationships. Bound-Layer Meteorol 7:363–374CrossRef
- Flesch TK (1996) The footprint for flux measurements, from backward Lagrangian stochastic models. Bound-Layer Meteorol 78:399–404CrossRef
- Foken T, Leclerc MY (2004) Methods and limitations invalidation of footprint models. Agric For Meteorol 127:223–234CrossRef
- Friend AD, Arneth A, Kiang NY, Lomas M, Ogee J, Rodenbeck C, Running SW, Santaren JD, Sitch S, Viovy N, Woodwards FI, Zaehle S (2007) FLUXNET and modelling the global carbon cycle. Glob Change Biol 13:610–633CrossRef
- Gash JHC (1986) A note on estimating the effect of a limited fetch on micrometeorological evaporation measurements. Bound-Layer Meteorol 35:409–414CrossRef
- Guan DX, Wu JB, Zhao XS, Yu GR (2006) CO2 fluxes over an old, temperate mixed forest in northeastern China. Agric For Meteorol 137:138–149CrossRef
- Holwerda F, Burkard R, Eugster W, Scatena FN, Meesters AG, Bruijnzeel LA (2006) Estimating fog deposition at a Puerto Rican elfin cloud forest site: comparison of the water budget and eddy covariance methods. Hydrol Process 20:2669–2692CrossRef
- Horst TW, Weil JC (1992) Footprint estimation for scalar flux measurements in the atmospheric surface layer. Bound-Layer Meteorol 59:279–296CrossRef
- Horst TW, Weil JC (1994) How far is far enough—the fetch requirements for micrometeorological measurement of surface fluxes. J Atmos Ocean Technol 11:1018–1025CrossRef
- Hsieh CI, Katul GG, Schieldge J, Sigmon JT, Knoerr KR (1997) The Lagrangian stochastic model for fetch and latent heat flux estimation above uniform and non-uniform terrain. Water Resour Res 33:427–438CrossRef
- Klaassen W, Sogachev A (2006) Flux footprint simulation downwind of a forest edge. Bound-Layer Meteorol 121:459–473CrossRef
- Kljun N, Kormann R, Rotach M, Meixner FX (2003) Comparison of the Lagrangian footprint model LPDM-B with an analytical footprint model. Bound-Layer Meteorol 106:349–355CrossRef
- Kljun N, Calanca P, Rotach MW, Schmid HP (2004) A simple parameterisation for flux footprint predictions. Bound-Layer Meteorol 112(3):503–523CrossRef
- Kormann R, Meixner FX (2001) An analytic footprint model for non-neutral stratification. Bound-Layer Meteorol 99:207–224CrossRef
- Kustas WP, Anderson MC, French AN, Vickers D (2006) Using a remote sensing field experiment to investigate flux-footprint relations and flux sampling distributions for tower and aircraft-based observations. Adv Water Resour 29:355–368CrossRef
- Leclerc MY, Thurtell GW (1990) Footprint prediction of scalar fluxes using a Markovian analysis. Bound-Layer Meteorol 52:247–258CrossRef
- Lloyd CR (1995) The effect of heterogeneous terrain on micrometeorological flux measurements: a case study from HAPEX-SAHEL. Agric For Meteorol 73:209–216CrossRef
- Nagy MT, Janssens IA, Yuste JC, Carrara A, Ceulemans R (2006) Footprint-adjusted net ecosystem CO2 exchange and carbon balance components of a temperate forest. Agric For Meteorol 139:344–360CrossRef
- Ono K, Miyata A, Yamada T (2008) Apparent downward CO2 flux observed with open-path eddy covariance over a non-vegetated surface. Theor Appl Climatol 92:195–208CrossRef
- Rebmann C, Göckede M, Foken T, Aubinet M, Aurela M, Berbigier P, Bernhofer C, Buchmann N, Carrara A, Cescatti A, Ceulemans R, Clement R, Elbers AJ, Granier A, Grünwald T, Guyon D, Havránková K, Heinesch B, Knohl A, Laurila T, Longdoz B, Marcolla B, Markkanen T, Miglietta F, Moncrieff J, Montagnani L, Moors E, Nardino M, Ourcival JM, Rambal S, Rannik Ü, Rotenberg E, Sedlak P, Unterhuber G, Vesala T, Yakir D (2005) Quality analysis applied on eddy covariance measurements at complex forest sites using footprint modeling. Theor Appl Climatol 80:121–141CrossRef
- Schmid HP (1994) Source areas for scalars and scalar fluxes. Bound-Layer Meteorol 67:293–318CrossRef
- Schmid HP (1997) Experimental design for flux measurements: matching scales of observations and fluxes. Agric For Meteorol 87:179–200CrossRef
- Schmid HP (2002) Footprint modeling for vegetation atmosphere exchange studies: a review and perspective. Agric For Meteorol 113:159–283CrossRef
- Schmid HP, Oke TR (1988) Estimating the source area of a turbulent flux measurement over a patchy surface. Preprint in: the 8th symposium on turbulence and diffusion. Am Meteorol Soc, Boston, pp 123–126
- Schuepp PH, Leclerc MY, MacPherson JI, Desjardins RL (1990) Footprint prediction of scalar fluxes from analytical solutions of the diffusion equation. Bound-Lay Meteorol 50:355–373CrossRef
- Sogachev A, Leclerc MY, Karipot A, Zhang G, Vesala T (2005a) Effect of clearcuts on footprints and flux measurements above a forest canopy. Agric For Meteorol 133:182–196CrossRef
- Sogachev A, Panferov O, Gravenhorst G, Vesala T (2005b) Numerical analysis of flux footprints for different landscapes. Theor Appl Climatol 80:169–185CrossRef
- van Ulden AP (1978) Simple estimates for vertical diffusion from sources near the ground. Atmos Environ 12:2125–2129CrossRef
- Vourlitis GL, Oechel WC, Hope A, Stow D, Boynton B, Verfaillie J Jr, Zulueta R, Hastings SJ (2000) Physiological models for scaling plot-measurements of CO2 flux across an arctic tundra landscape. Ecol Appl 10:60–72
- Zhao X, Guan D, Wu J, Jin C, Han S (2004) Zero-plane displacement and roughness length of the mixed forest of broad-leaved and Korean-pine in Changbai Mountain. Chin J Ecol 23(5):84–88
For further details log on website :
http://link.springer.com/article/10.1007/s10310-014-0437-2
No comments:
Post a Comment