A study of the water level variation of Lake Balkhash:Its influencing factors based on wavelet analysis [基于小波分析的巴尔喀什湖水位变化特征及其影响因素]

作者：Huang K.; Ma L.^*; Abuduwaili J.

来源：Arid Zone Research, 2020, 37(3): 570-579.

DOI：10.13866/j.azr.2020.03.04

• Central Asia
• Climate change
• Lake Balkhash
• Runoff
• Water level
• Wavelet analysis

Based on the annual average lake level of the Lake Balkhash, runoff of Ili River, and the meteorological data in the basin, we analyzed the characteristics and regularity of the average water level change of Lake Balkhash from 1880 to 2016 by using the wavelet time-frequency analysis method. Water balance data showed that the runoff in the lower reaches of the Ili River is a key factor controlling variation in the lake level. Cross-wavelet analysis was applied to further analyze the relationship between the lake level changes and the main meteorological factors. The results suggested that the main cycle for 83 a is the central scale, with an average period of lake level change for 54 a. The lake level has experienced three transitions in water abundance and dryness since 1880, and it will gradually enter the next dry season in the future. The cross-wavelet analysis revealed that precipitation is the main driver of lake level change under natural conditions. In addition, the transition of the resonance cycle phase between temperature and runoff in the late 1980s indicates that the increasing meltwater supply due to rising temperature results in the recovery of lake level, instead of a negative effect of evaporation loss. The variation in runoff and lake level can be influenced by atmospheric circulation in the region through its control on precipitation. The relationship of cross-wavelet analysis between NAO and runoff is more closely related than SOI, which plays a more important role in lake level changes.

• 单位
  荒漠与绿洲生态国家重点实验室; 中国科学院大学