TSWS: An observation-based streamflow dataset of Tianshan Mountains watersheds (1901-2019)

Due to scarcity of data and complex hydrological conditions in the Tianshan region, long-term and complete streamflow data are lacking. This study produced a multi-basin streamflow dataset, named Tianshan watershed streamflow (TSWS) dataset, by comparing the results of Hydrologiska Byråns Vattenavdelning and Long Short-Term Memory models, and analyzed spatiotemporal variation of streamflow.TSWS dataset provides daily streamflow data for 56 watersheds and monthly streamflow data for 89 watersheds in the Tianshan Mountains in 1901-2019. The streamflow simulations of 40 watersheds (daily scale) and 70 watersheds (monthly scale) passed the S-tests (Nash-Sutcliffe efficiency ≥0.5, percent bias ≤25%, and ratio of the root-mean-square error to the standard deviation of measured data ≤0.7). The dataset showed an overall increasing trend of streamflow, especially from 1990 to 2019; spatially, it showed higher streamflow in the west and south, and lower streamflow in the east and north. The dataset provides the first comprehensive simulation and its long time series will provide an important reference for climatic and hydrological studies.