## 2 Data and Study Area  
### CMIP5 Simulations  
The NEX-GDDP project provides downscaled global climate simulation results from CMIP5 with the spatial resolution of 0.25 \({}^{\circ}\) (\(\sim\)25 km \(\times\) 25 km) [28], including 21 GCM models and two of the four greenhouse gas emissions scenarios known as RCP (RCP4.5 and RCP8.5, respectively) by using a statistical downscaling algorithm. The downscaled method used in the NEX-GDDP dataset is the Bias-Correction Spatial Disaggregation (BCSD) method, which was developed by [PERSON] et al. [29] and has been widely used in climate change simulation [30; 31]. In the BCSD, the reference global data is from Global Meteorological Forcing Dataset (GMFD) for Land Surface Modeling, which was produced by the Terrestrial Hydrology Research Group at Princeton University [32]. More details about NEX-GDDP could be found in [PERSON] et al. [28].  
As a new generation statistically downscaled climate dataset, NEX-GDDP has been proved to give more precious and more reliable projections compared with original CMIP5 GCM simulations [25; 33; 34].  
According to the original spatial resolution of CMIP5, we choose ten representative models, which have relatively higher original spatial resolution and are from different countries and research groups. All of these models have been widely used in the study of climate change. The institution, country and original spatial resolution information is listed in Table 1.  
\begin{table}
\begin{tabular}{l c c c} \hline \hline \multirow{2}{*}{**Institution**} & \multirow{2}{*}{**Model**} & \multicolumn{2}{c}{**Spatial**} & \multirow{2}{*}{**Country**} \\  & & **Resolution** & \\  & & **(Lon\(\times\)Lat, degree)** & \\ \hline Centre National de Recherches Meteorologiques/Centre & & & \\ European de Recherche et Formation Avance en Calcul & CNRM-CM5 & 1.40\({}^{\circ}\times 1.40^{\circ}\) & France \\ Scientifique (CNRM–CERFACS) & & & \\ Atmosphere and Ocean Research Institute (The & & & \\ University of Tokyo), National Institute for & & & \\ Environmental Studies, and Japan Agency for & & & \\ Marine-Earth Science and Technology (MIROC) & & & \\ National Science Foundation, Department of Energy, & & \\ National Center for Atmospheric Research & & & \\ Commonwealth Scientific and Industrial Research & & & \\ Organization (CSIRO) and Bureau of Meteorology & & ACCESS1.0 & 1.25\({}^{\circ}\times 1.875^{\circ}\) & Australia \\ (BOM), Australia & & & \\ National Center For Atmospheric Research(NCAR) & & & \\ Commonwealth Scientific and Industrial Research & & & \\ Organization in collaboration with the Queensland & & & \\ Climate Change Centre of Excellence(CSIRO-QCCCE), & & & \\ Australia & & & \\ Institute for Numerical Mathematics(INM), Russia & INM-CM4 & 2.0\({}^{\circ}\times 1.5^{\circ}\) & Russia \\ Institute Pierre-Simon Laplace (IPSL), France & IPSL-CMSA-MR & 1.267\({}^{\circ}\times 3.750^{\circ}\) & France \\ Max Planck Institute for Meteorology(MPI-M),Germany & MPI-ESM-MR & 1.875 \(\times\) 1.875 & Germany \\ Meteorological Research Institute(MRI), Japan & MRI-CGCM3 & 1.125 \(\times\) 1.125 & Japan \\ \hline \hline \end{tabular}
\end{table}
Table 1: Information on the 10 climate models used in the present analysis.  
RCP4.5 and RCP8.5 are two radiative forcing pathways to 4.5 W/m\({}^{-2}\) (equivalent to 650 ppm CO\({}_{2}\) concentration) and 8.5 W/m\({}^{-2}\) (equivalent to 1370 ppm CO\({}_{2}\) concentration) by 2100 respectively. These two scenarios could represent the expected and most serious scenarios. Therefore, these two scenarios are widely used to analyze climate change [9; 16].  
Based on the ten CMIP5 models results under two scenarios (RCP4.5 and RCP8.5), the Multi-Model Ensemble (MME) results based on equal-weighted strategy are used for the following analysis in the 21 st century.