Eastward propagation of the intraseasonal variability of sea ice and the atmospheric field in the marginal ice zone in the Antarctic

We investigate the intraseasonal variability of the sea-ice concentration i n the Antarctic marginal ice zone (MIZ), using daily sea-ice and atmospheri c data for eight winters (1990-97). From 5-31 day band-pass filtered sea-ic e concentration data for the whole sea-ice region, it is clearly shown that the lower-latitude MIZ has the maximum intraseasonal variability, taking t he form of a narrow, circumpolar belt with alternately increasing and decre asing areas. This coherent pattern propagates eastward as a wave. A similar wave also appeared for the atmospheric field around the MIZ. The eastward propagating waves for sea-ice and the atmosphere have almost same propertie s, a wavenumber of 2-4, a period of 10-15 days, and a phase velocity of 10- 18 degrees/day. The common propagating signatures suggest a close relations hip between the intraseasonal variability of sea-ice and atmospheric field in the Antarctic MIZ in winter.