Insoluble particles in Antarctic ice: background aerosol size distribution and diatom concentration

Insoluble particle size distributions were measured covering the radius range 0.05-1.31 μm for six sections of ice core from Dome C, Antarctica. Two of the sections are from the Holocene, two are from the last glacial maximum (LGM), and another two are from the period that preceded it. Concludes that the southern hemisphere insoluble background aerosol size distribution has not changed significantly over the 26 000 year period studied. The concentration of diatoms in a sample of Holocene ice is compared with that in two samples of LGM ice and it is found that the concentration of diatoms whose largest dimension was ≥ 10 μm was 20 times larger during the LGM, the same as the ratio measured for the concentration of insoluble particles. The higher dust levels were mainly due to an increase in wind strength rather than to increased continental aridity. -from Authors