Evaluation of Remotely Sensed Evapotranspiration Over the CEOP EOP-1 Reference Sites

In this paper, the Coordinated Enhanced Observing Period (CEOP) data during an Enhanced Observing Period (EOP-1) is used to assess the Surface Energy Balance System (SEBS) model. The purpose of this study is to evaluate the adaptability of SEBS to different climatic zones and land cover classifications at two different scales. The SEBS model was examined at the field (tower) scale based primarily on in-situ observations from CEOP sites. To examine a broader scale application, remotely sensed land surface temperature (LST) from the MODIS sensor and surface meteorology from the Global Land Data Assimilation System (GLDAS) were used for the required forcing datasets. Comparisons at tower scale show that the model predictions of the energy fluxes agree reasonably well with the observations. The root mean square error (RMSE) of the ET prediction based on MODIS Land Surface Temperature (LST) plus CEOP meteorological observations is about 61 W m � 2 at a grassland site (Cabauw) and a needle leaf forest site (BERMS). The RMSE of ET predication at a corn site (Bondville) is 96 W m � 2 and the corresponding percentage error is 28.9%. When GLDAS forcing was used instead of the CEOP tower observations, the RMSEs of ET prediction at Cabauw, BERMS and Bondville are increased to 82, 84 and 140 W m � 2 respectively. The negative bias of surface downward radiative forcing from GLDAS contributed much to the larger deviation of the ET prediction when compared to tower based values. The innovative aspects of our study in this paper are: a) No similar work on evaluating remote sensing based ET model under a diverse climate and land cover condition has been done before; b) ET modeling was assessed in different scales ranging from site scale to GLDAS grid cell; c) The framework of estimating the spatial distribution of ET combining satellite data and available ground meteorology is tested.

[1]  J. Monteith.  Evaporation and surface temperature , 2007 .

[2]  Steven W. Running,et al.  Comparisons of land cover and LAI estimates derived from ETM+ and MODIS for four sites in North America: a quality assessment of 2000/2001 provisional MODIS products , 2003 .

[3]  S. Bridgham,et al.  ECOSYSTEM CONTROL OVER TEMPERATURE AND ENERGY FLUX IN NORTHERN PEATLANDS , 1999 .

[4]  Craig S. T. Daughtry,et al.  Estimation of the soil heat flux/net radiation ratio from spectral data , 1990 .

[5]  C. Woodcock,et al.  Evaluation of the MODIS LAI algorithm at a coniferous forest site in Finland , 2004 .

[6]  Jeffrey P. Walker,et al.  THE GLOBAL LAND DATA ASSIMILATION SYSTEM , 2004 .

[7]  G. Heinemann,et al.  An integrated approach for the determination of regionale vapotranspiration using mesoscale modelling, remote sensing and boundary layer measurements , 2001 .

[8]  S. Running,et al.  Global products of vegetation leaf area and fraction absorbed PAR from year one of MODIS data , 2002 .

[9]  Franz X. Meixner,et al.  Biogeochemical cycling of carbon, water, energy, trace gases, and aerosols in Amazonia: The LBA‐EUSTACH experiments , 2002 .

[10]  Z. Wan,et al.  Quality assessment and validation of the MODIS global land surface temperature , 2004 .

[11]  N. C. Strugnell,et al.  First operational BRDF, albedo nadir reflectance products from MODIS , 2002 .

[12]  Ann Henderson-Sellers,et al.  The Project for Intercomparison of Land Surface Parameterization Schemes (PILPS): Phases 2 and 3 , 1995 .

[13]  William P. Kustas,et al.  Use of remote sensing for evapotranspiration monitoring over land surfaces , 1996 .

[14]  Eric F. Wood,et al.  Scaling behaviour of hydrological fluxes and variables: Empirical studies using a hydrological model and remote sensing data , 1995 .

[15]  J. Chen,et al.  Defining leaf area index for non‐flat leaves , 1992 .

[16]  Alan H. Strahler,et al.  Global land cover mapping from MODIS: algorithms and early results , 2002 .

[17]  A. Verhoef,et al.  A comparison of surface fluxes at the HAPEX-Sahel fallow bush sites , 1997 .

[18]  Zhao-Liang Li,et al.  A physics-based algorithm for retrieving land-surface emissivity and temperature from EOS/MODIS data , 1997, IEEE Trans. Geosci. Remote. Sens..

[19]  Shafiqul Islam,et al.  Effects of subgrid‐scale heterogeneity of soil wetness and temperature on grid‐scale evaporation and its parameterization , 1998 .

[20]  Matthew F. McCabe,et al.  Modeling Evapotranspiration during SMACEX: Comparing Two Approaches for Local- and Regional-Scale Prediction , 2005 .

[21]  M. Menenti,et al.  Mesoscale climate hydrology: the contribution of the new observing systems , 1999 .

[22]  Eric F. Wood,et al.  Evapotranspiration and runoff from large land areas: Land surface hydrology for atmospheric general circulation models , 1991 .

[23]  R. Dickinson,et al.  The Project for Intercomparison of Land Surface Parameterization Schemes (PILPS): Phases 2 and 3 , 1993 .

[24]  W. Brutsaert.  Evaporation into the atmosphere , 1982 .

[25]  Anton Beljaars,et al.  Cabauw Data for the Validation of Land Surface Parameterization Schemes , 1997 .

[26]  H. E. Dunsmore,et al.  Software engineering metrics and models , 1986 .

[27]  C. Priestley,et al.  On the Assessment of Surface Heat Flux and Evaporation Using Large-Scale Parameters , 1972 .

[28]  Thomas L. Delworth,et al.  Climate variability and land-surface processes , 1993 .

[29]  Alan K. Betts,et al.  Albedo over the boreal forest , 1997 .

[30]  Eric F. Wood,et al.  Effects of Spatial Variability and Scale on Areally Averaged Evapotranspiration , 1995 .

[31]  P. Vidale,et al.  Land–atmosphere energy exchange in Arctic tundra and boreal forest: available data and feedbacks to climate , 2000, Global change biology.

[32]  J. A. Franco,et al.  Spatial representativity of the possible sites for measuring the water balance of apricot trees , 2002 .

[33]  Wilfried Brutsaert,et al.  Aspects of bulk atmospheric boundary layer similarity under free‐convective conditions , 1999 .

[34]  Massimo Menenti,et al.  Estimation of sensible heat flux using the Surface Energy Balance System (SEBS) and ATSR measurements , 2003 .

[35]  Roger A. Pielke,et al.  Land–atmosphere energy exchange in Arctic tundra and boreal forest: available data and feedbacks to climate , 2000, Global change biology.

[36]  H. L. Penman.  Natural evaporation from open water, bare soil and grass , 1948, Proceedings of the Royal Society of London. Series A. Mathematical and Physical Sciences.

[37]  W. Rouse,et al.  Energy partitioning at treeline forest and tundra sites and its sensitivity to climate change , 1995 .

[38]  A. Huete,et al.  Overview of the radiometric and biophysical performance of the MODIS vegetation indices , 2002 .

[39]  A. Holtslag,et al.  A remote sensing surface energy balance algorithm for land (SEBAL)-1. Formulation , 1998 .

[40]  Douglas E. Ahl,et al.  Effects of aggregated classifications of forest composition on estimates of evapotranspiration in a northern Wisconsin forest , 2002 .

[41]  Z. Su.  The Surface Energy Balance System (SEBS) for estimation of turbulent heat fluxes , 2002 .

[42]  M. G. Ryan,et al.  A physiological basis for biosphere-atmosphere interactions in the boreal forest: an overview. , 1997, Tree physiology.

[43]  J. Chen.  Spatial Scaling of a Remotely Sensed Surface Parameter by Contexture , 1999 .