Exploration of elemental details of single mineral dust particles in the EPICA Dome C ice core during interglacial and glacial periods

Abstract

The single particle inductively coupled plasma time-of-flight mass spectrometer (sp-ICP-TOFMS, model: icpTOF R from TOFWERK, Switzerland) coupled to the Bern continuous flow analysis (CFA) has demonstrated its ability to resolve signals of individual insoluble particles in the meltwater. This offers valuable insights into the characteristics of mineral dust obtained from the elemental composition of the mineral dust as - in contrast to bulk analyses - it allows deciphering of the complete elemental range of particle composition, which can be a mixture of different minerals (Erhardt et al. 2019).  To apply this new technique for the first time to sections of an Antarctic ice core covering several glacial and interglacial stages, we conducted aerosol chemical CFA measurements on a selection of 18 Antarctic EPICA Dome C (EDC) 55 cm ice core sections, from both glacial and interglacial periods over the last 800 kyr using CFA-sp-ICP-TOFMS. We present the new preliminary results of our CFA campaign with a nominal 55 cm bag mean resolution (or 110 cm where two consecutive bags were measured). The depth resolution corresponds to a time period in the range of 40 to 602 years of precipitation history in the Holocene, the last glacial period, and various marine isotope stages (MIS 9, 11, 15, 16, 17, and 18). Our goal is to extract detailed information about changes in climate and environmental conditions from individual elemental mineral dust particles. We compare the element-bearing particle number concentration (PNC) measured with sp-ICP-TOFMS for both major and minor crustal elements to the dust PNC optically measured with a laser absorption particle sensor (Abakus from Klotz, Germany), irrespective of its elemental composition, providing a complementary perspective. Furthermore, we examine the variability of dust composition using the elemental mass ratio of individual mineral dust particles during different warm and cold periods.