During three summer campaigns in January/February 2000, 2001, and 2002 the ionic composition of the aerosol at the European Project for Ice Coring in Antarctica (EPICA) deep-drilling site at Kohnen Station was measured in daily resolution. In 2000 and 2002 we observed mean (¿std) non-sea-salt sulfate (nss-SO42-) concentrations of 353 ¿ 100 ng m-3 and 320 ¿ 250 ng m-3, as well as methane sulfonate (MS) concentrations of 59 ¿ 36 ng m-3 and 74 ¿ 80 ng m-3, respectively. For the summer campaign in 2001, significantly lower nss-SO42- and MS levels of 164 ¿ 150 ng m-3 and 19 ¿ 12 ng m-3, respectively, were typical. The mean MS/nss-SO42- ratio ranged from about 0.1 to 0.2. MS and nss-SO42- concentrations and their variability were roughly comparable to coastal stations at summer. Supported by air mass back trajectory analyses, this finding documented an efficient long-range transport to Kohnen via the free troposphere. MS/nss-SO42- ratios exhibited a strong dependence on the MS concentration with systematically higher ratios at higher MS concentrations, a peculiarity which is also evident in a firn core drilled at this site.