Analysis of seasonal sea-ice cover of an area measuring 1.25 x 10⁶ km² off the northwestern side of the Antarctic Peninsula indicates that there were four periods of extensive ice cover during the last 18 years. Variability in seasonal timing, areal extent, seasonal duration and persistence of sea-ice over multiple years is apparent and is consistent with features described by Stammerjohn and Smith (1996) for ice cover in the Bellingshausen Sea. Periods of extensive winter ice cover peaked in 1980, 1986, 1991and 1995 and were foreshadowed by the late retreat of ice during the springs of 1985, 1990 and 1994. Ice cover during the summer months and winter ice cover during years between periods of extensive ice cover decreased during the second half of the time series. Maximum ice cover during the periods of extensive ice cover did not change. Annual curves of sea-ice cover were integrated over time to produce an annual index of sea-ice cover in units of 10⁶ km²/month. This index may be used in conjunction with studies of variability in biological production, particularly the reproductive success of Antarctic krill, in the Antarctic Peninsula area.