干旱区生态环境知识资源中心

We examined climate variability at two timescales for northern Xinjiang, China: one is of the past 500 years using dendrochronology data and the other is of the past 50 years using meteorological station data. The regression models built from the 50-year period were used to reconstruct the climate of the 500-year period. The results indicate that climate underwent many alternating warm-cold and wet-dry periods in the past 500 years. For the 50-year period, we applied the Mann-Kendall jump test to data from 48 meteorological stations to identify possible transition points of temperature and precipitation. For this period, we also analyzed the impacts of latitude, altitude, slope aspect, and human activities on climate variability, aiming to recognize major factors that influence regional climate variability. The results show a warming and wetting trend in the recent 50 years in northern Xinjiang. We determined that natural pattern variability is dominant in the long-term climate variability in the region, but human impacts are non-negligible in the past 50 years. Regional climate variability may be associated with or driven by latitude, altitude, ecosystems, topography, and human activities. The study provides an empirical evidence of the unique regional characteristics of inland river basin in an arid area over the global climate change background.