Abstract:The effects of atmospheric mass loading (ATML) on GPS fiducial stations in Crustal Motion Observation Network of China are studied. The historical data are reanalyzed in a consistent way and the results derived from three categories of solutions: global reference frame solutions, regional frame solutions, and regional frame solutions with ATML corrections at the observation level (the phase of processing daily observations with GAMIT software) are analyzed as well. The magnitudes of white noises and flicker noises, seasonal terms, and estimation of rates and rate uncertainties are compared with each other. It is shown that applying nontidal ATML corrections at the observation level can bring about small improvements in reducing the magnitudes of horizontal white noises and vertical flicker noises, as well as vertical annual fluctuations; however, it does little effects to rate estimations.