## 2 Materials and Methods
### Model-Specific Parameters  
The parameterization schemes of STEPS, SCOPE, and TSEB significantly differ, reflecting their unique approaches to ET estimation. STEPS focuses on soil properties and land cover characteristics, utilizing soil hydraulic parameters and land cover-specific canopy physiological attributes. SCOPE adopts a more complex structure with sub-modules for radiative transfer, energy balance, aerodynamics, and leaf biochemistry. TSEB, relatively simpler, relies on energy balance principles, with key parameters including the Priestley-Taylor coefficient (\(\alpha\)PT) and soil resistance constants. Despite these differences, generic parameter settings are applied across the Mediterranean region for this study as follows. Parameters in STEPS cover soil hydraulics for water movement in Table 3. Land cover-specific canopy characteristics (Table 4) like canopy structure by leaf area index, canopy water content, light conditions conducive to optimal photosynthesis, photosynthetically active photon flux density (PPFD), and stomatal conductance coefficients are given in Table 4 for computing photosynthetic and transpiration rates throughout leaf and canopy. SCOPE is rather more complex in its parameterization and structure. It has sub-modules for simulating radiative transfer at both leaf and canopy scales, energy balance modeling for leaf and soil temperature simulations, aerodynamics fitting for resistances, and calculations related to leaf biochemistry. Table 5 provides a detailed reference for key parameters within the SCOPE, in which the canopy roughness length, leaf drag coefficient, maximum carboxylation rate, and parameters related to the Ball-Berry stomatal conductance model are included, their theoretical details are in [39; 40]. \begin{table}
\begin{tabular}{p{56.9 pt} p{113.8 pt} p{113.8 pt} p{113.8 pt} p{113.8 pt}} \hline \hline
**Model** & **Time Frequency** & **Resolution** & **Approach** & **Inputs** \\ \hline \multirow{4}{*}{STEPS} & \multirow{4}{*}{Daily} & \multirow{4}{*}{10 km} & \multicolumn{4}{p{113.8 pt}}{Radiative transfer mechanism, sunlit} \\  & & & and shaded leaf schemes, soil–water balancing (saturated and unsaturated zones), Penman Montieth, coupled water, and energy flux & MODIS LAI, ERA5 \\ \hline SCOPE & Daily & 10 km & \begin{tabular}{p{113.8 pt}} Radiative transfer mechanism, sunlit and shaded, energy partitioning for 60 canopy layers, and energy balancing \\ \end{tabular} & \begin{tabular}{p{113.8 pt}} MODIS LAI, ERA5 \\ Manualcover, ERA5 VSMC \\ \end{tabular} \\ \hline TSEB & Daily & 10 km & \
\begin{tabular}{p{113.8 pt}} Two-layer energy partitioning, \\ LST-driven heat fluxes, and heat transfer mechanism modulated by resistances \\ \end{tabular} &
\begin{tabular}{p{113.8 pt}} ERA5 reanalysis, ESA \\ landcover, LAI and LST from SEVIRI-MSG \\ \end{tabular} \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Modeled ET inputs, frequency, resolution sources, and estimation approach. \begin{table}
\begin{tabular}{p{56.9 pt} p{113.8 pt} p{113.8 pt} p{113.8 pt} p{113.8 pt} p{113.8 pt} p{113.8 pt} p{113.8 pt} p{113.8 pt} p{113.8 pt}} \hline \hline \multirow{2}{*}{**Texture**} & \multirow{2}{*}{**KO Decay Rate**} & \multirow{2}{*}{**KS Horizontal**} & \multirow{2}{*}{**Soil B**} & \multicolumn{2}{p{113.8 pt}}{**Suction Head**} & \multicolumn{2}{p{113.8 pt}}{**KS Head**} & \multicolumn{2}{p{113.8 pt}}{**Soil Depth**} & \multicolumn{2}{p{113.8 pt}}{**Wilting Point**} & \multicolumn{2}{p{113.8 pt}}{**Field Capacity**} & \multirow{2}{*}{**Porosity**} & \multicolumn{2}{p{113.8 pt}}{**Max Surface Conductance**} \\ \hline
10 & 0.07 & 10 & 4.05 & 0.45 & 15.21 & 2 & 0.03 & 0.22 & 0.437 & 0.01 \\
20 & 0.067 & 9.8 & 4.09 & 0.45 & 16 & 2 & 0.035 & 0.22 & 0.437 & 0.001 \\
30 & 0.03 & 6 & 4.9 & 0.45 & 50 & 0.7 & 0.1 & 0.21 & 0.435 & 0.002 \\
40 & 0.005 & 3 & 5.3 & 0.786 & 3 & 0.7 & 0.13 & 0.33 & 0.501 & 0.004 \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Hydraulic properties of four soil texture classes used in STEPS model.