3.3 Determination of the water vapor mass trajectory
In order to better estimate the contribution rate of lake evaporation in
the Xiying Reservoir, our research first judged the characteristics of
the movement path of the advection water vapor which affects the
precipitation of Xiying Reservoir, so as to determine the initial value
of advection water vapor. Therefore, this research used TrajStat
software and the global data assimilation system data for calculation of
airflow backward trajectory at 500m height of the Xiying Reservoir for
72 hours during sampling period based on HYSPLIT Model. The Angle
Distance algorithm was used to cluster all the air mass trajectories.