In the cases in which the snow distribution is patchy, we construct a general SDC relation between SD and SCF. Of course, the most reliable method is to construct different regional SDCs under different topographic conditions. However, there are few data to construct these relations. Although there are 94 stations with snow observations in the study region, there are almost no continuous observations nor enough data to support the regression of SDC under different conditions because of the short snow period and missing observations. Therefore, we suggest a compromise in this study, in which the SDC is constructed based on the mean in situ SD of all stations. There are good correlations between the averaged in situ SD and SCF, indicating that the SDC concept, used in many other studies,45,46 is also suitable to the TP region. Although there are some calibrated SDCs in other study regions with good data,47 those calibrated parameters could not be used directly in the TP, because the snow in this region has features that differ from those of other regions. Liston et al.48 also indicated that the key parameters will be dependent upon different topographic scales. With only SCF assimilation, Lannoy et al.28 indicated that the simulated timing of the onset of the snow season was improved, but without an improvement of SWE amounts. There are many reasons for the result, but mostly the complex relationship between SCF and SWE is responsible. Since we could not calibrate regional SDC in the TP based on the existing observations, a general SDC is reasonable as a substitute. The results show relevant simulation results that are close to the truth.