## 2 Data and Methods
### Sensitivity Analysis Methods
#### 2.3.1 Morris Screening Method  
Morris screening is a qualitative global sensitivity analysis method first proposed by [PERSON] in 1991 that calculates the relative sensitivity of model parameters with low computational cost, and sorts the sensitivity of model parameters [21; 22]. In the process of Morris sample generation, a base sample point \(X^{1}\) is first generated on which the disturbance factor variable \(\Delta=s/(1-p)\) is added to generate other sample points \(X^{i}\). After generating different sample points, \(M+1\) sample points are obtained, and the specific process is obtained with the following equation:  
\[B^{*}=\Big{\{}J_{M+1,1}X^{(1)}+(\Delta/2)[(2\times B-J_{M+1,1})D+J_{M+1,1}] \Big{\}}\text{P} \tag{1}\]  
where \(B^{*}\) is the \((M+1)\times M\) parameter sample matrix, each row represents a parameter sample, and \(M\) is the number of model parameters. \(J\) is the identity matrix. \(D\) is an \(M\times M\) diagonal matrix, and each diagonal element had the same probability as that of \(\pm 1\). P \begin{table}
\begin{tabular}{c c c} \hline \hline
**Parameters** & **Description** & **Hydrologic Process** \\ \hline CN2 & Initial SCS runoff curve number for moisture condition II & Surface runoff processes \\ SURLAG & Surface runoff lag coefficient & \\ \hline ESCO & Surface runoff lag coefficient & \\ EFOO & Plant uptake compensation factor & Potential and actual evapotranspiration \\ CANMX & Maximal canopy storage (mm H\({}_{2}\)O) & processes \\ SOL\_ALB & Moist soil albedo & \\ \hline SOL\_Z & Depth from the soil surface to the bottom of the layer (mm) & \\ SOL\_BD & Moist bulk density (Mg/m\({}^{3}\) or g/cm\({}^{3}\)) & Soil water processes \\ SOL\_AWC & Available water capacity of the soil layer (mm H\({}_{2}\)O/mm soil) & \\ SOL\_K & Saturated hydraulic conductivity (mm/h) & \\ \hline GW\_REVAP & Groundwater evapotranspiration coefficient & \\ GW\_DELAY & The delay time & \\ REVAPMN & Threshold depth of water in the shallow aquifer for evapotranspiration or & \\ REVAPMN & percolation to the deep aquifer to occur (mm H\({}_{2}\)O) & Groundwater processes \\ GWQMN & Threshold depth of water in the shallow aquifer required for return flow to & \\  & occur (mm H\({}_{2}\)O) & \\ ALPHA\_BF & Baseflow alpha factor (1/day) & \\ RCHRG\_DP & Deep aquifer percolation fraction & \\ \hline CH\_K2 & Effective hydraulic conductivity in main channel alluvium (mm/h) & \\ CH\_N2 & Manning’s “n” value for the main channel & Channel water routing processes \\ ALPHA\_BNK & Baseflow alpha factor for bank storage (days) & \\ \hline SMFMX & Melt factor for snow on 21 June (mm H\({}_{2}\)O/\({}^{\circ}\)C/day) & \\ SMFMN & Melt factor for snow on 21 December (mm H\({}_{2}\)O/\({}^{\circ}\)C/day) & \\ SFTMP & Snowfall temperature (\({}^{\circ}\)C) & Snow processes \\ SMTMP & Snow melt base temperature (\({}^{\circ}\)C) & \\ TIMP & Snowpack temperature lag factor. & \\ \hline SLSUBBSN & Surface runoff lag coefficient & \\ OV\_N & [PERSON]’s “n” value for overland flow & Time of concentration processes \\ CH\_N1 & [PERSON]’s “n” value for the tributary channels & \\ \hline CH\_K1 & Effective hydraulic conductivity in tributary channel alluvium (mm/h) & Transmission losses from surface runoff \\ \hline HRU\_SLP & Average slope steepness (m/m) & Lateral flow processes \\ \hline TLAPS & Temperature lapse rate (\({}^{\circ}\)C/km) & Elevation bands \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Description and hydrological process of 30 selected parameters. is \(M\times M\) random confusion matrix. \(X^{(1)}\) is the primary sample of a row vector. At the same time,  
\[B= \begin{bmatrix}0&0&0&\cdots&0\\ 1&0&0&\cdots&0\\ 1&1&0&\cdots&0\\ 1&1&1&\cdots&0\\ \vdots\vdots\vdots\\ 1&1&1&1&1\end{bmatrix}  \tag{2}\]  
The generated parameter sample matrix \(B^{*}\) has the following characteristics. There was only one different parameter value in the model parameter samples of two adjacent rows, and the parameter values of the other M-1 models were identical.