The southernmost boundary of the PFZ (and hence, the southern border of the subantarctic region) is the Antarctic Convergence, located approximately 200 kilometers south of the Antarctic Polar Front (APF).
Sydgrænsen for PFZ (og dermed også sydgrænsen for den subantarktiske region) er den antarktiske konvergens, som findes ca. 200 km syd for den antarktiske polarfront (APF).