Sudden stratospheric warmings (SSWs) are important processes that exert impacts on tropospheric weather and climate. This study used the duration to describe the variations in the displacement SSWs and defined Pacific–North American (PNA) and Western Pacific (WP) combined indices (PWC Index) to describe the combinations of PNA and WP. We found that the duration of the displacement SSWs (SSW1) first increased and then decreased around 2000. The decadal variation in SSW1 can be explained by PWC Index, since the teleconnection combinations with the same signs (+PNA+WP/−PNA−WP) can affect upward planetary wave 1 and SSW1 more efficiently than +PNA−WP/−PNA+WP. The second mode of tropical Pacific sea surface temperature plays a more important role in modulating the decadal variations in PWC Index and displacement SSWs than the first mode.