深圳市降水变化特征及其未来变化情况预测

基于1998—2018年深圳市日降水资料,采用降水相对变率、集中度及集中期分析了月尺度、年尺度降水稳定性及其年内分配特征,运用Mann-Kendall非参数法和相关函数法对深圳市年降水量、降水稳定性和分配特征参数的变化趋势、突变特征及其未来降水变化特征进行分析与预估。结果表明:深圳市汛期降水稳定性比非汛期更好,年际降水分布稳定性较差,降水集中期为每年6—8月份,降水集中度处于0.23~0.72;降水量和降水分布特征参数均在2011—2013年发生突变,在发生突变后降水相对变率和集中度呈下降趋势,而年降水量和集中期呈上升趋势;深圳市未来降水序列变化趋势受过去变化特征的影响,其中未来年降水量有减少的趋势,降水集中程度逐渐增强,降水稳定性逐渐变差,年内降水分配均匀性变差,降水集中期持续向后推迟。研究成果为深圳市合理蓄水和用水提供科学依据,对水资源调度、利用以及防汛抗旱具有实际指导意义和重要的学术价值。

Variation Characteristics and Future Changes ofPrecipitation in Shenzhen

On the basis of daily precipitation data from 1998 to 2018, we examined the stability and annual distribution characteristics of precipitation in monthly scale and annual scale in Shenzhen City by analyzing the relative variability, precipitation concentration degree (PCD) and precipitation concentration period (PCP) of the rainfall data. In subsequence, we analyzed the trends and abrupt changes and estimated the future changes of precipitation characteristics by using Mann-Kendall nonparametric method and correlation function method. Results revealed that the precipitation stability in Shenzhen in flood season was more stable than that in non-flood season, and the interannual precipitation distribution was less stable; rainfall concentrated from June to August, with a PCD of 0.23-0.72; precipitation amount and distribution parameter both witnessed abrupt changes during 2011-2013, while after the abrupt changes, the relative variability and PCD underwent downward trend whereas annual precipitation amount and PDP upward trends. In future, the precipitation series in Shenzhen is affected by past trends, of which the annual precipitation amount would go downward, PCD would intensify, precipitation would be less stable, annual precipitation would be less uniform, and PCP would delay continuously. The research findings offer scientific basis for rational water storage and water use in Shenzhen, and are of practical guiding significance for the dispatching, utilization of water resources and flood control in Shenzhen.