Knowledge of microparticle geometry is essential for accurate calculation of ice core volume-related dust metrics (mass, flux, and particle size distributions) and subsequent paleoclimate interpretations, yet particle shape data remain sparse in most of ice core records. The approach and results of this work are of interest for the broad geoscience community, since it potentially enables a better characterization of all data obtained from the dust in ice cores. This study of samples from South Pole ice core (SPC14) indicates that coarser particles (>5.0 μm diameter) show greater variation in measured aspect ratios than finer particles (<5.0 μm). While fine particle volumes can be accurately estimated using the spherical assumption, applying the same assumption to coarse particles has a large effect on inferred particle volumes.
Knowledge of microparticle geometry is essential for accurate calculation of ice core...
Ice core microparticle data typically use geometry assumptions to calculate particle mass and flux. We use dynamic particle imaging, a novel technique for ice core dust analyses, combined with traditional laser particle counting and Coulter counter techniques to assess particle shape in the South Pole Ice Core (SPC14) spanning 50–16 ka. Our results suggest that particles are dominantly ellipsoidal in shape and that spherical assumptions overestimate particle mass and flux.
Ice core microparticle data typically use geometry assumptions to calculate particle mass and...