Sulphate and chloride aerosols during Holocene and last glacial periods preserved in the Talos Dome Ice Core, a peripheral region of Antarctica

Abstract

A B S T R A C T Antarctic ice cores preserve the record of past aerosols, an important proxy of past atmospheric chemistry. Here we present the aerosol compositions of sulphate and chloride particles in the Talos Dome (TD) ice core from the Holocene and Last Glacial Period. We find that the main salt types of both periods are NaCl, Na 2 SO 4 and CaSO 4 , indicating that TD ice contains relatively abundant sea salt (NaCl) from marine primary particles. By evaluating the molar ratio of NaCl to Na 2 SO 4 , we show that about half of the sea salt does not undergo sulphatisation during late Holocene. Compared to in inland Antarctica, the lower sulphatisation rate at TD is probably due to relatively little contact between sea salt and sulphuric acid. This low contact rate can be related to a reduced time of reaction for marine-sourced aerosol before reaching TD and/or to a reduced post-depositional effect from the higher accumulation rate at TD. Many sulphate and chloride salts are adhered to silicate minerals. The ratio of sulphate-adhered mineral to particle mass and the corresponding ratio of chloride-adhered mineral both increase with increasing dust concentration. Also, the TD ice appears to contain Ca(NO 3 ) 2 or CaCO 3 particles, thus differing from aerosol compositions in inland Antarctica, and indicating the proximity of peripheral regions to marine aerosols.

Compositions of Dust and Sea Salts in the Dome C and Dome Fuji Ice Cores From Last Glacial Maximum to Early Holocene Based on Ice‐Sublimation and Single‐Particle Measurements

“…We classify the measured particles into four categories: "terrestrial dust," "sea salts," "mixture of terrestrial dust and sea salts," and "others/unknown," according to the combinations of detected elements, which are consistent with previous works for the DF, Talos Dome, and NEEM (Greenland) ice cores (Iizuka et al, 2009;Iizuka, Tsuchimoto, et al, 2012;Iizuka, Uemura, et al, 2012;Iizuka et al, 2013Iizuka et al, , 2016Oyabu et al, 2014Oyabu et al, , 2015; Figure 2). Below, we describe the typical particle compositions for each classification and discuss the uncertainties associated with possible misclassifications.…”

Spatial distributions of soluble salts in surface snow of East Antarctica

“…For salt concentrations, both the combination sublimationÁEDS method and the IDM method have a close relationship at depths from the surface snow to 4-m depth in the Dome Fuji region (Iizuka et al, 2012b). However, the relation is less close for Holocene ice of the Talos Dome ice core (Iizuka et al, 2013), which was drilled in a coastal area (Delmonte et al, 2010;Stenni et al, 2011). Specifically, the particles in the Talos Dome ice contain a lot of NaCl according to the sublimationÁEDS method.…”

“…Another area with this same issue is the Talos Dome site. Holocene ice at Talos Dome has a certain amount of NaCl yet is mismatched with the IDM (Iizuka et al, 2013 does not form NaCl. Similarly, Holocene ice in the Dome Fuji ice core has negligible NaCl, yet closely matches the IDM (Iizuka et al, 2012a(Iizuka et al, , 2012bOyabu et al, 2014).…”

Chemical compositions of sulfate and chloride salts over the last termination reconstructed from the Dome Fuji ice core, inland Antarctica

“…Using this method, Iizuka et al . [, ] showed that sea salt in Talos Dome, a peripheral dome, remains a primary aerosol as NaCl during warm periods, whereas more than 90% of the sea salt in Dome Fuji came from a secondary aerosol as Na 2 SO 4 . With the same method, Iizuka et al .…”