Abstract
Recent advances in land data assimilation have yielded variational smoother techniques designed to solve the surface energy balance based on remote observations of surface radiometric temperature. These approaches have a number of potential advantages over existing diagnostic models, including the ability to make energy flux predictions between observation times and reduced requirements for ancillary parameter estimation. Here, the performance of a recently developed variational smoother approach is examined in detail over a range of vegetative and hydrological conditions in the southern U.S.A. during the middle part of the growing season. Smoother results are compared with flux tower observations and energy balance predictions obtained from the two-source energy balance model (TSM). The variational approach demonstrates promise for flux retrievals at dry and lightly vegetated sites. However, results suggest that the simultaneous retrieval of both evaporative fraction and turbulent transfer coefficients by the variational approach will be difficult for wet and/or heavily vegetated land surfaces. Additional land surface information (e.g. leaf area index (L AI) or the rough specification of evaporative fraction bounds) will be required to ensure robust predictions under such conditions. The single-source nature of the variational approach also hampers the physical interpretation of turbulent transfer coefficient retrievals. Intercomparisons between energy flux predictions from the variational approach and the purely diagnostic TSM demonstrate that the relative accuracy of each approach is contingent on surface conditions and the accuracy with which L AI values required by the TSM can be estimated.
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M. C. Anderson J. M. Norman G. R. Diak W. P. Kustas J.R. Mecikalski (1997) ArticleTitle‘A Two-Source Time-Integrated Model for Estimating Surface Fluxes from Thermal Infrared Satellite Observations’ Remote Sens. Environ 60 195–216
W. Bastiaansen M. Menenti R. Feddes A. Holtslag (1998) ArticleTitle‘A Remote Sensing Surface Energy Balance Algorithm for Land (SEBAL) 1. Formulation’ J. Hydrol 212–213 198–212
A. K. Betts J. H. Ball (1998) ArticleTitle‘FIFE Surface Climate and Site-Averaged Dataset 1987–1989’ J. Atmos. Sci 55 1091–1108
G. D. Boni F. Castelli D. Entekhabi (2001) ArticleTitle‘Sampling Strategies and Assimilation of Ground Temperature for the Estimation of Surface Energy Fluxes’ IEEE Trans. Geosci. Rem. Sens 39 165–172
G. D. Boni D. Entekhabi F. Castelli (2000) ArticleTitle‘Land Data Assimilation with Satellite Measurements for the Estimation of Surface Energy Balance Components and Surface Control of Evaporation’ Water Resour. Res 37 1713–1722
F. Caparrini F. Castelli D. Entekhabi (2003) ArticleTitle‘Mapping of Land-Atmosphere Heat Fluxes and Surface Parameters with Remote Sensing Data’ Boundary-Layer Meteorol 107 605–633
F. Caparrini F. Castelli D. Entekhabi (2004) ArticleTitle‘Estimation of Surface Turbulent Fluxes through Assimilation of Radiometric Surface Temperature Sequences’ J. Hydrometeorol 5 145–159
F. Castelli D. Entekhabi E. Caporali (1999) ArticleTitle‘Estimation of Surface Heat Flux and an Index of Soil Moisture Using Adjoint-State Surface Energy Balance’ Water Resour. Res 35 3115–3125
B. J. Choudhury (1987) ArticleTitle‘Relationships between Vegetation Indices, Radiation Absorption, and Net Photosynthesis Evaluated by a Sensitivity Analysis’ Remote Sens. Environ 22 209–233
B. J. Choudhury N. U. Ahmed S. B. Idso R. J. Reginato C. Daughtry (1994) ArticleTitle‘Relations between Evaporation Coefficients and Vegetation Indices Studied by Model Simulation’ Remote Sens. Environ 50 1–17
R. D. Crago W. Brutsaert (1996) ArticleTitle‘Daytime Evaporation and Self-Preservation of the Evaporative Fraction and the Bowen Ratio’ J. Hydrol 180 173–194
G. R. Diak J. R. Mecikalski M. C. Anderson J. M. Norman W. P. Kustas R. D. Torn R.L. DeWolf (2004) ArticleTitle‘Estimating Land Surface Energy Budgets from Space: Review and Current Efforts at the University of Wisconsin-Madison and USDA-ARS’ Bull. Amer. Meteorol. Soc 85 65–78
French, A. N., Schmugge, T. J., Kustas, W. P., Brubaker, K. L., and Prueger, J.: 2003, ‘Surface Energy Fluxes over El Reno, Oklahoma Using High-Resolution Remotely Sensed Data’, Water Resour. Res. 39, doi:10.1029/2002WR001734.
J. R. Garratt B. B. Hicks (1973) ArticleTitle‘Momentum, Heat, and Water Vapour Transfer to and from Natural and Artificial Surfaces’ Quart. J. Roy. Meteorol. Soc 99 25435–25446
Hollinger, S. E. and Daughtry, C. S. T.: 1999, Southern Great Plains 1997 Hydrological Experiment: Vegetation Sampling and Data Documentation, Technical Report to the United States Department of Agricultural on Contract AG-58-1270-7-043.
L. Jiang S. Islam (2001) ArticleTitle‘Estimation of Surface Evaporation Map over Southern Great Plains Using Remote Sensing Data’ Water Resour. Res 37 329–340
W. P. Kustas D. C. Goodrich (1994) ArticleTitle‘Preface to MONSOON’90 Special Issue’ Water Resour. Res 30 1211–1225
W. P. Kustas J. M. Norman (1999a) ArticleTitle‘Reply to Comments about the Basic Equations of Dual-Source Vegetation-Atmosphere Transfer Models’ Agric. For. Meteorol. 94 275–278
W. P. Kustas J. M. Norman (1999b) ArticleTitle‘Evaluation of Soil and Vegetation Heat Flux Predictions Using a Simple Two-Source Model with Radiometric Temperature for Partial Canopy Cover’ Agric. For. Meteorol. 94 13–29
W. P. Kustas J. M. Norman (2000a) ArticleTitle‘Evaluating the Effects of Subpixel Heterogeneity on Pixel Average Fluxes’ Remote Sens. Environ. 74 327–342
W. P. Kustas J. M. Norman (2000b) ArticleTitle‘A Two-source Energy Balance Approach Using Directional Radiometric Temperature Observations for Sparse Canopy Covered Surfaces’ Agron. J. 92 847–854 Occurrence Handle10.2134/agronj2000.925847x
W. P Kustas J. H. Blanford D. I. Stannard C. S. T. Daughtry W. D. Nichols M. A. Weltz (1994) ArticleTitle‘Local Energy Flux Estimates for Unstable Conditions Using Variance Data in Semi-Arid Rangelands’ Water Resour. Res 30 1351–1361
W. P. Kustas J. M. Norman T. J. Schmugge M.C. Anderson (2004) ‘Mapping Surface Energy Fluxes with Radiometric Temperature’ D. Quattrochi J. Luvall (Eds) Thermal Remote Sensing in Land Surface Processes Taylor and Francis New York 205–253
W. P. Kustas X. Zhan T. J. Schmugge (1998) ArticleTitle‘Combining Optical and Microwave Remote Sensing for Mapping Energy Fluxes in a Semiarid Watershed’ Remote Sens. Environ 64 116–131
J. M. Norman W. P. Kustas K. S. Humes (1995) ArticleTitle‘A Two-source Approach for Estimating Soil and Vegetation Energy Fluxes in Observations of Directional Radiometric Surface Temperature’ Agric. For. Meteorol 77 263–293
C. H. B. Priestley R. J. Taylor (1972) ArticleTitle‘On the Assessment of Surface Heat Flux and Evaporation Using Large-Scale Parameters’ Mon. Wea. Rev. 100 81–92
P. J. Sellers F. G. Hall G. Asrar D. E. Strebel R.E. Murphy (1992) ArticleTitle‘An Overview of the First International Satellite Land Surface Climatology Project (ISLCP) Field Experiment (FIFE)’ J. Geophys. Res 97 18345–18371 Occurrence Handle10.1029/92JE00958
W. J. Shuttleworth R. J. Gurney (1990) ArticleTitle‘The Theoretical Relationship between Foliage Temperature and Canopy Resistance in Sparse Crops’ Quart. J. Roy. Meteorol. Soc 116 497–519
W. J. Shuttleworth J. S. Wallace (1985) ArticleTitle‘Evaporation from Sparse Crops–An Energy Combination Theory’ Quart. J. Roy. Meteorol. Soc 111 839–855
Z. Su (2002) ArticleTitle‘The Surface Energy Balance System (SEBS) for Estimation of Turbulent Heat Fluxes’ Hydrol. Earth Syst. Sci 6 85–99 Occurrence Handle10.5194/hess-6-85-2002
T. E. Twine W. P. Kustas J. M. Norman D. R. Cook P. R. Houser T. P. Meyers J. H. Prueger P. J. Starks M. L. Wesley (2000) ArticleTitle‘Correcting Eddy-Covariance Flux Estimates over a Grassland’ Agric. For. Meteorol 103 279–300
S. Verma J. Kim R. J. Clement (1992) ArticleTitle‘Momentum Water Vapour, and Carbon Dioxide Exchange at a Centrally Located Prairie Site during FIFE’, J. Geophys. Res 97 18629–18639
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Crow, W.T., Kustas, W.P. Utility of Assimilating Surface Radiometric Temperature Observations for Evaporative Fraction and Heat Transfer Coefficient Retrieval. Boundary-Layer Meteorol 115, 105–130 (2005). https://doi.org/10.1007/s10546-004-2121-0
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DOI: https://doi.org/10.1007/s10546-004-2121-0