@article{fdi:010095557,
  title = {{A}ssessing the groundwater recharge of a steep-sided catchment from thermal-derived evapotranspiration estimates : usefulness of methods for correcting topographical effects},
  author = {{S}ebbar, {B}. {E}. and {S}imonneaux, {V}incent and {K}habba, {S}. and {C}hehbouni, {A}bdelghani and {M}erlin, {O}.},
  editor = {},
  language = {{ENG}},
  abstract = {{E}vapotranspiration ({ET}), a key component of the hydrological cycle, is commonly derived on a global scale from thermal-infrared remote sensing data. {T}hermal-derived {ET} estimates can hence be used to assess the water budget of land surfaces. {H}owever, significant uncertainties in such {ET} data can lead to non-closure of the water balance. {T}his is particularly the case in rugged catchments where topography introduces substantial variability in the meteorological forcing of {ET} models, whose systematic errors propagate through the water balance calculation. {T}his study addresses the limited attention given to topographical effects on thermal-based {ET} by developing a daily framework for {ET} mapping that accounts for topography ({ET}-{TOPO}+). {I}ts usefulness is evaluated by comparison to two widely used {ET} products, {W}a{POR} and {SSEB}op, in estimating groundwater recharge ({GWR}) in a steep-sided catchment in the {H}igh {A}tlas, {M}orocco, from 2017 to 2022, using in-situ measurements of streamflow and precipitation. {W}a{POR} and {SSEB}op do notaccount for topography while {ET}_{TOPO}+ corrects for the topography-induced variability in meteorological conditions. {A}ssessment against in-situ measurements at two contrasted sites shows that {ET}_{TOPO}+ provides the most accurate monthly {ET} estimates with higher correlation (an average of 0.81) and minimal bias (a maximum of -5 mm/month). {A}t the annual scale (2017-2022), {GWR} ranged from -110 to + 42 mm/year ({SSEB}op), -104 to +27 mm/year ({W}a{POR}), and -86 to +71 mm/year ({ET}_{TOPO}+). {T}he inter-annual water balance assessment shows that {ET}_{TOPO}+ provides the most realistic {GWR} considering the morphological and geological context, averaging 1 mm/year over five hydrological years. {SSEB}op and {W}a{POR} produced values of -58 and -33 mm/year, respectively, showing an overall overestimation of both {ET} products at watershed scale since negative values are unrealistic in this context. {T}hese findings highlight the importance of considering the topographical influence on thermal-derived {ET} estimates in assessing terrestrial water-cycle dynamics and water resources.},
  keywords = {{R}emote sensing ; {E}vapotranspiration ; {T}opographic correction ; {G}roundwater recharge ; {W}ater balance ; {M}ountains ; {MAROC} ; {HAUT} {ATLAS}},
  booktitle = {},
  journal = {{J}ournal of {H}ydrology},
  volume = {664},
  numero = {{B}},
  pages = {134457 [17 ]},
  ISSN = {0022-1694},
  year = {2026},
  DOI = {10.1016/j.jhydrol.2025.134457},
  URL = {https://www.documentation.ird.fr/hor/fdi:010095557},
}