Abstract
Principal component analysis was performed on displacements of GPS stations in and around Izu Peninsula in 1997. As the first component, displacements due to earthquake swarm activity in March was extracted. The second component had high factor loading in height component of all stations. The second component is supposed to be due to estimation error of range between antennas and satellites. Pattern of temporal change of the component is similar to that of barometric pressure in winter and to atmospheric temperature in summer . It suggests the component be related to atmospheric delay .
