Uncertainties of Water Fluxes in Soil–Vegetation–Atmosphere Transfer Models: Inverting Surface Soil Moisture and Evapotranspiration Retrieved from Remote Sensing

摘要: Effective hydraulic parameters of soil–vegetation–atmosphere transfer (SVAT) models can be derived by inverting observed surface soil moisture, θ obs , and evapotranspiration, ET retrieved from remote sensing. We investigated the uncertainties in simulating water fluxes contrasting hydroclimatic scenarios for which it was assumed that had a RMSE 0.04 m 3 −3 (Δθ ) relative error 20% (ΔET ). The correlation simulated (ΔWF sim with Δθ ΔET proposed Uncertainty Simulator Algorithm. results show ΔWF is influenced climate increases when drier. uncertainty estimated root-zone found to correlated . prediction evaporation contained large actual/potential evapotranspiration ratio. transpiration under dry climates were high ; however, wet insignificant. groundwater recharge but reduced climates. Furthermore, not In general, as (i) gets drier, (ii) texture coarser, or (iii) roots grow deeper. explained moisture decoupling. Soil decoupling occurs information provided no longer representative θ. Transpiration there substantially more storage at depth. propose methodology reduce nonuniqueness inverted parameters.