Trends in Temperature and Precipitation in the Zhangweinan River Basin during the last 53 Years

Based on monthly mean temperature and precipitation data for 53 years, from 1957 to 2009, recorded at the Zhangweinan River Basin and five main meteorological stations around it, the non-parametric Mann-Kendall trend test method and cumulative anomaly methods were adopted to analyze the long-term trends here of such key meteorological elements as annual mean temperature, maximum temperature, minimum temperature and precipitation; the corresponding Hurst index was calculated; and future change trends for various meteorological elements were predicted. The results of the analyses indicate that: there is an inconspicuous downward trend in annual precipitation for the Zhangweinan River Basin, with large decreases appearing in summer, with an M-K slope of -11.82mm/10a; the annual mean temperature rises more significantly, and the M-K slope of the whole Basin's annual mean temperature reaches 0.17 degrees C/10a, the temperature increase being significant in spring and winter. According to the Hurst Index calculations, the annual mean temperature and precipitation series show strong continuity in the Zhangweinan River Basin, which indicates that the future trend will be consistent with that of the past. These research results will not only help provide evidence for the climate change in the Zhangweinan River Basin but can also lay the foundation for further studies on water resources security evaluation in conditions of climate change. (C) 2011 Published by Elsevier B.V. Selection and/or peer-review under responsibility of School of Environment, Beijing Normal University.