Spatial Ion Concentration Variability - continued

Ca, Mg, and K are shown in Fig. 9, 10, and 11, respectively. Concentration values range from 0.1 ppb to 740 ppb for Ca, from 0.2 ppb to 1,930 ppb for Mg, and from 0.1 ppb to 600 ppb for K. All three species show overall low concentration values across Antarctica with a few distinctive exceptions. Local dust sources such as the McMurdo Dry Valleys, a strong marine influence such as Terra Nova, or coastal sites at the Antarctic Peninsula cause orders of magnitude higher concentrations. Intermediate concentration levels are rare. The continent-wide pattern might therefore be used to distinguish typical ‘global’ or hemispherical dust content from local Antarctic sources.