Microparticle Analysis of the Ross Ice Shelf Q-13 Core and Preliminary Results From THE J-9CORE

The concentration and size distribution of microparticles are measured on the Ross Ice Shelf at three sites: Q-13, base camp, and J-9. Results from the analysis of 2 611 samples representing the 100 m core from site Q-13 are presented. Increasing particle concentrations since 1800 are interpreted as a reflection of the gradual movement of the Q-13 drill site northward toward the Ross Sea under greater influence of the dissipating cyclonic storms in the Ross embayment. A substantial increase in particle concentrations found between 1920–40 may reflect an increase in the frequency and/or intensity of cyclonic storms dissipating in the Ross Sea. This is under investigation. Preliminary microparticle analyses of a small portion of each of 39 sections from the 416 m J-9 core indicate a substantial increase in particle concentrations between 250 and 350 m, possibly signaling the presence of late glacial, or Wisconsin, ice