Atmospheric circulation patterns and the spatial variability of atmospheric chemistry and moisture transport in central West Antarctica are investigated using new 40 year long (1954--1994 A.D.) glaciochemical and accumulation rate records developed from four firn cores from this region. The cores sites lie on a 200 km traverse from 82¿ 22' S, 119¿ 17' W to 81¿ 22' S, 107¿ 17' W. The glaciochemical records represent the major ionic species present in Antarctic snow: Na+, K+, Mg2+, Ca2+, Cl-, NO3-, and SO42-. High spatial variability appears in comparisons of full record averages and poor intersite linear correlation results. Accumulation rates show 50--100% changes over distances of 50--100 km and sea-salt concentrations drop by 50% between the middle two sites. One likely contributor to the high variability seen at this spatial scale is variability in synoptic- and finer-scale meteorology. Empirical orthogonal function (EOF) analysis shows that 80% or more of the variance in site chemistry can be attributed to two types of air masses: winter season air (50--70% of site variance) with a strong marine signature (heavy loading of sea-salt species) and summer season air (21% of the variance), marked by marine biogenic non-sea-salt SO4 plus NO3. This pattern of winter and summer regimes appears at other West Antarctic sites suggesting it may apply to the entire region. We show that a general picture of the patterns of variability in West Antarctica can best be drawn by using an analysis technique that fully exploits high resolution, multiparameter, multisite data sets. ¿ 1999 American Geophysical Union