Results of balloon borne soundings with electrochemical ozone sondes carried out at 70,77¿ S; 11,85¿ E are discussed. During polar spring in 1985 the high time resolution of soundings (about 12 launches per months) gives a detailed picture on the vertical distribution and height variations of different maxima of ozone partial pressure near the margin of the ozone hole crossing the continental coast above Queen Maud Land in recent time. ¿ American Geophysical Union 1987