基于GRACE RL06的云贵高原水储量变化反演及分析

云贵高原河流湖泊众多、季节性水文活动剧烈,监测其水储量长期变化具有重要意义。联合利用GRACE RL06数据及GLDAS进行云贵高原陆地、地表和地下水储量变化反演,针对GRACE信号泄露、C20项误差和区域水储量加权策略进行了对比研究,并利用相关性分析、趋势分析和L-S时频分析对2003年1月至2010年12月云贵高原水储量变化时序进行了特征分析。结果表明,GRACE与GLDAS反演水储量时序之间相关系数达0.94,且两者变化趋势一致;水储量变化年周期显著,并存在0.5、2、3年周期;2003~2010年底地下水储量变化以2007年6月为节点,呈先减后增趋势,分别为-4.4、0.7mm/a,且总体呈增加趋势,为5.4mm/a,有效揭示了2003~2006年夏季干旱及2010年初严重干旱的旱情发展过程。

Inversion and Analysis of Water Storage Variations in Yunnan-Guizhou Plateau Based on GRACE RL06

It is of great significance to monitor the long-term water storage variations in Yunnan-Guizhou Plateau since this region has the large number of rivers and lakes, the vigorous seasonal hydrologic activities. The terrestrial water storage (TWS) variations, surface water variations and groundwater storage (GWS) variations in Yunnan-Guizhou Plateau are estimated by the gravity recovery and climate experiment mission (GRACE) RL06 data and global land data assimilation system (GLDAS) model. A comparative study is investigated on GRACE signal leakage, C20 error and the weighted strategy of regional water storage variations. Correlation analysis, trend analysis and L-S spectral analysis method are employed to analyze the time series of water storage variations in Yunnan-Guizhou Plateau from January 2003 to December 2010. The results show that the correlation coefficient between water storage variations time series derived from GRACE and GLDAS is 0.94, and the variations trend of both is consistent; The annual period of water storage variations is significant, and there are semi-annual, two years and three years period; With June 2007 as the time node, the GWS variations from year 2003 to 2010 show firstly decrease and then slowly increase, respectively -4.4 mm/a and 0.7 mm/a, and the overall increase trend is 5.4 mm/a. So, it effectively reveals the summer drought in 2003-2006 and the drought development process of severe drought in early 2010.