基于小波分析的伊塞克湖水位变化特征

根据伊塞克湖1950—2010年期间的年平均水位资料，采用趋势分析和小波分析，对伊塞克湖年平均水位变化时间序列进行研究，从而揭示伊塞克湖水位变化的总体趋势和周期性变化规律。结果表明:（1） 1950—2010年期间，伊塞克湖水位总体呈下降趋势，共下降1.27 m，1950—1997年水位持续下降，1998年开始转为上升。（2） 20世纪90年代之前，人类活动是引起湖泊水位下降的主要驱动因子；20世纪90年代后，在全球气候变化的作用下，该地区降水量的增加影响到径流量的增加，从而引起湖泊水位的缓慢上升。（3） 1950—2010年间的周期性分析结果显示，伊塞克湖年平均水位存在21 a的主周期，并且2010年以后的一段时间伊塞克湖水位处于偏高时期。

Water Level Variations of Issyk-Kul Lake Based on Wavelet Analysis

Based on the average annual water level data of Issyk-Kul Lakefrom 1950 to 2010, using trend analysis and Morlet Wavelet analysis to study the Issyk-Kul Lake average annual water level, which reveals the overall trend and periodic variation regularity of water level of Issyk-Kul Lake. The results show as followings: (1) Water level presented overall downward trend, decline in total 1.27 m in the period from 1950 to 2010, water level continued to decline from 1950 to 1997,water level began to rise in 1998. (2) Before the 1990s, human activities are the main driving factor causing the lake level decline, the increased precipitation of the region increased runoff due to the role of global climate change, causing the water level to rise slowly. (3) Results from the Periodic analysis of 1950—2010 showed that Issyk-Kul Lake water level change primary period was 21-year, and the period of time Issyk-Kul Lake water level remain rising after 2010.