气候变化领域集成服务门户(CCPortal): Assessment of actual evapotranspiration over a semiarid heterogeneous land surface by means of coupled low-resolution remote sensing data with an energy balance model: Comparison to extra-large aperture scintillometer measurements

CCPortal

DOI	10.5194/hess-22-2187-2018
	Assessment of actual evapotranspiration over a semiarid heterogeneous land surface by means of coupled low-resolution remote sensing data with an energy balance model: Comparison to extra-large aperture scintillometer measurements
	Saadi S.; Boulet G.; Bahir M.; Brut A.; Delogu É.; Fanise P.; Mougenot B.; Simonneaux V.; Chabaane Z.L.
发表日期	2018
ISSN	1027-5606
起始页码	2187
结束页码	2209
卷号	22 期号:4
英文摘要	In semiarid areas, agricultural production is restricted by water availability; hence, efficient agricultural water management is a major issue. The design of tools providing regional estimates of evapotranspiration (ET), one of the most relevant water balance fluxes, may help the sustainable management of water resources. Remote sensing provides periodic data about actual vegetation temporal dynamics (through the normalized difference vegetation index, NDVI) and water availability under water stress (through the surface temperature Tsurf), which are crucial factors controlling ET. In this study, spatially distributed estimates of ET (or its energy equivalent, the latent heat flux LE) in the Kairouan plain (central Tunisia) were computed by applying the Soil Plant Atmosphere and Remote Sensing Evapotranspiration (SPARSE) model fed by low-resolution remote sensing data (Terra and Aqua MODIS). The work's goal was to assess the operational use of the SPARSE model and the accuracy of the modeled (i) sensible heat flux (H) and (ii) daily ET over a heterogeneous semiarid landscape with complex land cover (i.e., trees, winter cereals, summer vegetables). SPARSE was run to compute instantaneous estimates of H and LE fluxes at the satellite overpass times. The good correspondence (R2 D0.60 and 0.63 and RMSED57.89 and 53.85W m-2 for Terra and Aqua, respectively) between instantaneous H estimates and large aperture scintillometer (XLAS) H measurements along a path length of 4 km over the study area showed that the SPARSE model presents satisfactory accuracy. Results showed that, despite the fairly large scatter, the instantaneous LE can be suitably estimated at large scales (RMSED47.20 and 43.20W m-2 for Terra and Aqua, respectively, and R2 D0.55 for both satellites). Additionally, water stress was investigated by comparing modeled (SPARSE) and observed (XLAS) water stress values; we found that most points were located within a 0.2 confidence interval, thus the general tendencies are well reproduced. Even though extrapolation of instantaneous latent heat flux values to daily totals was less obvious, daily ET estimates are deemed acceptable. © Author(s) 2018.
语种	英语
scopus关键词	Agriculture; Evapotranspiration; Heat flux; Latent heat; Scintillation; Vegetation; Water management; Actual evapotranspiration; Agricultural productions; Agricultural water management; Energy balance models; Heterogeneous land surfaces; Large aperture scintillometers; Normalized difference vegetation index; Sustainable management; Remote sensing; Aqua (satellite); assessment method; energy balance; equipment; evapotranspiration; heat flux; land surface; model; MODIS; NDVI; remote sensing; resolution; semiarid region; Terra (satellite); water availability; water budget; water stress; Tunisia
来源期刊	Hydrology and Earth System Sciences
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/160060
作者单位	Saadi, S., Centre D'Etudes Spatiales de la Biosphère, Université de Toulouse, CNRS, CNES, IRD, UPS, Toulouse, France, Université de Carthage, Institut National Agronomique de Tunisie, LR17AGR01-GREEN-TEAM, Tunis, Tunisia; Boulet, G., Centre D'Etudes Spatiales de la Biosphère, Université de Toulouse, CNRS, CNES, IRD, UPS, Toulouse, France; Bahir, M., Centre D'Etudes Spatiales de la Biosphère, Université de Toulouse, CNRS, CNES, IRD, UPS, Toulouse, France; Brut, A., Centre D'Etudes Spatiales de la Biosphère, Université de Toulouse, CNRS, CNES, IRD, UPS, Toulouse, France; Delogu, É., Centre D'Etudes Spatiales de la Biosphère, Université de Toulouse, CNRS, CNES, IRD, UPS, Toulouse, France; Fanise, P., Centre D'Etudes Spatiales de la Biosphère, Université de Toulouse, CNRS, CNES, IRD, UPS, Toulouse, France; Mougenot, B., Centre D'Etudes Spatiales de la Biosphère, Université de Toulouse, CNRS, CNES, IRD, UPS, Toulouse, France; Simonneaux, V., Centre D'Etudes Spatiales de la Biosphère, Université de Toulouse, CN...
推荐引用方式 GB/T 7714	Saadi S.,Boulet G.,Bahir M.,et al. Assessment of actual evapotranspiration over a semiarid heterogeneous land surface by means of coupled low-resolution remote sensing data with an energy balance model: Comparison to extra-large aperture scintillometer measurements[J],2018,22(4).
APA	Saadi S..,Boulet G..,Bahir M..,Brut A..,Delogu É..,...&Chabaane Z.L..(2018).Assessment of actual evapotranspiration over a semiarid heterogeneous land surface by means of coupled low-resolution remote sensing data with an energy balance model: Comparison to extra-large aperture scintillometer measurements.Hydrology and Earth System Sciences,22(4).
MLA	Saadi S.,et al."Assessment of actual evapotranspiration over a semiarid heterogeneous land surface by means of coupled low-resolution remote sensing data with an energy balance model: Comparison to extra-large aperture scintillometer measurements".Hydrology and Earth System Sciences 22.4(2018).