The impact of climate changes on water level of Qinghai Lake in China over the past 50 years

Understanding the variation regularity of lake level and the potential driver factors can provide insights into lake conservation and management. In this study, inter- and inner-annual variations of lake level in Qinghai Lake during the period 1961-2012 were analyzed to determine whether climatic factor or runoff factor were responsible for the variations. The results showed that lake level decreased significantly during the period 1961-2004 at a rate of -7.6 cm/yr, while increasing significantly during the period 2004-2012 at a rate of 14 cm/yr, and all were significant at a p value of <0.01. Lake level was most sensitive to climate and river runoff. Precipitation and river runoff had directly positive effects on lake level, but inverse evaporation and wind speed played a significantly negative role on lake level. The relative contributions of influencing factors in the Southeast Asian monsoon (SEAM) and the westerly circulation periods on annual lake level variations were approximately 49.8% and 27.8%, respectively. The relative contributions of temperature, precipitation, evaporation, and wind speed on lake level variation were approximately 13.8%, 36.3%, 27.1%, and 18.4%, respectively. In general, the annual lake level was primarily influenced by precipitation and evaporation of the SEAM period.