Abstract:
Spatial and temporal distributions and influencing factors of extreme precipitation are important bases for coping with future climate change. The spatiotemporal variability and affecting factors of extreme precipitation indices (EPIs) in east of northwest China (ENW) during 1961-2015 were investigated using a series of approaches such as modified Mann-Kendall trend test, Hurst exponent, ensemble empirical mode decomposition (EEMD), and geodetector model. The results showed that CDD and CWD decreased significantly (P < 0.01), with rates of 1.4 days/decade and 0.07 days/decade, respectively. EPIs in ENW exhibited an obvious heterogeneity. CDD gradually increased from the southeast to the northwest. The remaining EPIs generally showed the opposite trend. Geodetector results demonstrated that large-scale circulation factors had a significant impact on EPIs in ENW. The influence of large-scale climate factors on EPIs was concentrated in nonlinear enhancement, and Nino3.4 and SO were the dominant driving factors that played a major role in the variability of EPIs. The results of this study provided a reference for ENW and other arid and semi-arid regions to cope with extreme climates and develop corresponding strategies.
摘要:
极端降水的时空分布及其影响因素是应对未来气候变化的重要依据。采用改良Mann-Kendall趋势检验等方法,对1961-2015年中国西北地区东部极端降水指数(EPIs)的时空变异性及其影响因素进行了研究,赫斯特指数,集成经验模式分解(EEMD),和地理探测器模型。结果显示CDD和CWD显著降低(P<0.01),费率为1.4天/十年和0.07天/十年,分别。ENW中的EPI表现出明显的异质性。CDD从东南向西北逐渐增加。其余的EPI通常表现出相反的趋势。地球探测器结果表明,大尺度环流因子对ENW中的EPI有重大影响。大尺度气候因素对经济影响指数的影响集中在非线性增强,Nino3.4和SO是在EPI变异性中起主要作用的主要驱动因素。本研究结果为ENW及其他干旱半干旱地区应对极端气候和制定相应策略提供了参考。