Abstract
The Bowen Ratio-Energy Balance (BREB) is an accurate method often used to measure the latent heat flux (λE) due to its simplicity and portability. However, its performance in advective areas is less clear and its accuracy may depend on the equality of eddy transfer coefficients for heat and water vapor. In this work, hourly measured λE of a reference crop (Festuca arundinacea Schreb.) using a BREB system was compared with lysimeter-measured λE under moderate to severe advective conditions. The lysimeter resolution for hourly records was 22.6 W m−2. The analysis of the eddy transfer coefficients was made using simultaneous measurements of fluxes and vertical gradients of temperature and humidity. To avoid computational problems when β→ −1, some hourly periods were discarded in the analysis. Rejected data amounted to 37% of the total, although the cumulative evapotranspiration (ET) during these hours did not exceed 13% of the total ET. The BREB method overestimated daily ET by an average of 5.5% and by 5.7% when only daylight hours were considered. Under stable atmospheric conditions the method was less accurate, with relative errors of 21% vs. 11% under unstable conditions. For daylight hours, accuracy was higher under unstable conditions (RMSE = 36.15 W m−2) than under stable conditions (RMSE = 50.20 W m−2), which had larger overestimations of ET (6.3 vs. 5.1%). The main source of error appears to come from insufficient fetch resulting in local advective conditions. Nevertheless, and from a purely practical perspective, under the advective conditions of these measurements the BREB technique provides accurate ET fluxes with limited errors.
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References
Allen RG, Fisher DF (1990) Low cost electronic weighing lysimeters. Trans ASAE 33(6):1823–1833
Allen RG, Pruitt WO, Jensen ME (1991) Environmental requirements of lysimeters. In: Proceedings of the ASCE specialty conference on “lysimeters for evapotranspiration and environmental measurements”, Honolulu, Hawaii, 23–25 July, 1991, pp170–191
Berengena J, Gavilán P (2005) Reference ET estimation in a high advective semi-arid environment. J Irrig Drain E-ASCE 131(2):147–163
Bink NJ (1997) The ratio of eddy diffusivities for heat and water vapour under conditions of local advection. Phys Chem Earth 21(3):119–122
Bowen JS (1926) The ratio of heat losses by conduction and by evaporation from any water surface. Phys Rev 27:779–787
Casa R, Russell G, Lo Casciom B (2000) Estimation of evapotranspiration from a field of linseed in central Italy. Agric For Meteorol 104:289–301
Colomer I, Villalobos FJ, Lourence F, Berengena J, Fereres E (1986) Instalación y calibrado de dos grandes lisímetros gravimétricos. In: Proceedings of the: V Jornadas Técnicas sobre Riegos Málaga, Spain, December 1986, p 6
Dugas WA, Fritschen LJ, Gay LW, Held AA, Matthias AD, Reicosky DC, Steduto P, Steiner JL (1991) Bowen ratio, eddy correlation, and portable chamber measurements of sensible and latent heat flux over irrigated spring wheat. Agric For Meteorol 56:1–20
Dyer AJ (1974) A Review of flux profile relationships. Bound-Lay Meteorol 7:363–372
Farahani HJ, Bausch WC (1995) Performance of Evapotranspiration models for maize–bare soil to closed canopy. T ASAE 38(4):1049–1059
Frangi JP, Garrigues C, Haberstock H, Forest F (1996) Evapotranspiration and stress indicator through Bowen ratio method. In: Camp CR, Sadler EJ, Yoder RE (eds) Evapotranspiration and írrigation scheduling. Proceedings of the international conference, San Antonio, TX, 3–6 November, pp800–805
Gavilán P (2002) La advección de calor sensible en el valle medio del Guadalquivir y su influencia en la medida y la estimación de la evapotranspiración de referencia. Tesis Doctoral leída en la Escuela Técnica Superior de Ingenieros Agrónomos y de Montes de la Universidad de Córdoba
Heilman JL, Brittin CL, Neale CMU (1989) Fetch requirements for Bowen ratio measurements of latent and sensible heat fluxes. Agric For Meteorol 44:261–273
Hillel D (1980) Fundamentals of soil physics. Academic Press Inc, New York, p 413
Ibáñez M, Castellví F (2000) Simplifying daily evapotranspiration estimates over short full-canopy crops. Agron J 92:628–632
Kjelgaard JF, Stockle CO, Villar Mir JM, Evans RG, Campbell GS (1994) Evaluating methods to estimated corn evapotranspiration from short-time interval weather data. T ASAE 37(6):1825–1833
Lang ARG, McNaughton KG, Fazu C, Bradley EF, Ohtaki E (1983) Inequality of eddy transfer coefficients for vertical transport of sensible and latent heats during advective inversions. Bound-Lay Meteorol 25:273–280
Laubach J, Raschendorfer M, Kreilein H, Gravenhorst G (1994) Determination of heat and water vapor fluxes above a spruce forest by eddy correlation. Agric For Meteorol 71:373–401
Laubach J, McNaughton KG (1998) A spectrum-independent procedure for correcting eddy flux measurements with separated sensors. Bound-Lay Meteorol 89:445–467
Laubach J, McNaughton KG, Wilson JD (2000) Heat and water vapour diffusivities near the base of a disturbed stable internal boundary layer. Bound-Lay Meteorol 94:23–63
McNaughton KG, Laubach J (1998) Unsteadiness as a cause of non-equality of eddy diffusivities for heat and vapour at the base of an advective inversion. Bound-Lay Meteorol 88:479–504
Motha RP, Verma SB, Rosenberg NJ (1979) Exchange coefficients under sensible heat advection determined by eddy correlation. Agric Meteorol 20:273–280
Ohmura A (1982) Objective criteria for rejecting data for Bowen ratio flux calculations. J Appl Meteorol 21:595–598
Ortega-Farias SO, Cuenca RH, Ek M (1996) Daytime variation of sensible heat flux estimated by the bulk aerodynamic method over a grass canopy. Agric For Meteorol 81:131–143
Pérez PJ, Castellví F, Ibáñez M, Rossell JI (1999) Assessment of reliability of Bowen ratio method for partitioning fluxes. Agric For Meteorol 97:141–150
Priestley CHB, Taylor RJ (1972) On the assessment of surface heat flux and evaporation using large-scale parameters. Mon Weather Rev 100(2):81–92
Prueger JH, Hatfield JL, Aase JK, Pikul JL Jr (1997) Bowen-ratio comparisons with lysimetric evapotranspiration. Agron J 89:730–736
Swinbank WC, Dyer AJ (1967) An experimental study in micro-meteorology. Q J R Meteorol Soc 93:494–500
Tanner BD, Swiatek E, Greene JP (1993) Density fluctuations and use of the krypton hygrometer in surface flux measurements. In: Allen RG, Neale CMU (eds) Proceedings of the national conference of irrigation and drainage engineering, Park City, Utah, American Society of Civil Engineers, New York, 21–23 July 1993, pp105–112
Todd RW, Evett SR, Howell TA (1998) Latent heat flux of irrigated alfalfa measured by weighing lysimeter and Bowen ratio-energy balance. In: Proceedings of the annual international meeting of ASAE, Orlando, Florida, 12–16 July 1998
Todd RW, Evett SR, Howell TA (2000) The Bowen ratio-energy balance method for estimating latent heat flux of irrigated alfalfa evaluated in a semi-arid, advective environment. Agric For Meteorol 103:335–348
Unland HE, Hourser PR, Shuttleworth WJ, Yang ZL (1996) Surface flux measurement and modeling at a semiarid Sonoran desert site. Agric For Meteorol 82:119–153
Verma SB, Rosenberg NJ, Blad BL (1978) Turbulent exchange coefficients for sensible heat and water vapor under advective conditions. J Appl Meteorol 17:330–338
Villalobos FJ (1997) Correction of eddy covariance water vapor flux using additional measurements of temperature. Agric For Meteorol 88:77–83
Webb EK, Pearman GI, Leuning R (1980) Corrections of flux measurements for density effects due to heat and water vapour transfer. Q J R Meteorol Soc 106:85–110
Willmott CJ (1982) Some comments on the evaluation of model performance. Bull Am Meteorol Soc 63(11):1309–1313
Acknowledgments
This study was financed by the Spanish National Institute of Agricultural Research (INIA) under the Project RTA01-124. The authors are grateful to two anonymous reviewers for their valuable comments and suggestions.
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Gavilán, P., Berengena, J. Accuracy of the Bowen ratio-energy balance method for measuring latent heat flux in a semiarid advective environment. Irrig Sci 25, 127–140 (2007). https://doi.org/10.1007/s00271-006-0040-1
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DOI: https://doi.org/10.1007/s00271-006-0040-1