A 125-year record of climate and chemistry variability at the Pine Island Glacier ice divide, Antarctica

Abstract

Abstract. The Mount Johns (MJ) ice core (79º55' S; 94º23' W) was drilled near the Pine Island Glacier ice divide on the West Antarctic Ice Sheet during the 2008–2009 austral summer, to a depth of 92.26 m. The upper 45 m of the record covers approximately 125 years (1883–2008) showing marked seasonal variability. Trace element concentrations in 2,137 samples were determined using inductively coupled plasma mass spectrometry. In this study, we reconstruct mineral dust and sea salt aerosol transport and investigate the influence of climate variables on the elemental concentrations to the MJ site. The ice core record reflects changes in emissions as well as atmospheric circulation and transport processes. Our trajectory analysis shows distinct seasonality, with strong westerly transport in the winter months and a secondary northeasterly transport in the summer. During summer months, the trajectories present slow-moving (short) transport and are more locally influenced than in other seasons. Finally, our reanalysis trace element correlations suggest that marine derived trace element concentrations are strongly influenced by sea ice concentration and sea surface temperature anomalies. The results show that seasonal elemental concentration maxima in sea-salt elements correlate well with the sea ice concentration winter maxima in the West Amundsen and Ross Seas. Lastly, we observed an increased concentration of marine aerosols when sea surface temperature decreased.

Mass and Number Size Distributions of rBC in Snow and Firn Samples From Pine Island Glacier, West Antarctica

“…Long‐range transport of large particles generated in the atmosphere far away from Antarctica has been suggested by Ellis et al (2016), which is not unreasonable considering mineral dust up to 5,000 nm can be transported over long distances (Gaiero et al, 2007; Mahowald et al, 2014) and be deposited in Antarctic snow (Delmonte et al, 2013; Li et al, 2008). Dust up to 2,400 nm has been found at the sampling site, associated with remote continental sources (e.g., South America—Cataldo et al, 2013; Schwanck et al, 2017), suggesting that large BC particles could also be transported this far. Further studies on rBC transport and deposition in snow, along with rBC size distributions from the atmosphere above it, would be of extreme value to improve our understanding in BC deposition in Antarctica.…”

“…Seasonal sample discrimination was based on the core dating presented in Marquetto, Kaspari, and Simões (2020). Antarctic ice core BC records show a well‐defined seasonality, with peak concentrations in the dry season due to increased biomass burning activity in the Southern Hemisphere (SH) during this time of the year (Bisiaux, Edwards, McConnell, Curran, et al, 2012; Sand et al, 2017; Winstrup et al, 2019); more efficient transport to the ice core site (Marquetto, Kaspari, & Simões, 2020; Neff & Bertler, 2015; Schwanck et al, 2017; Stohl & Sodemann, 2010); and weaker precipitation (Legrand & Mayewski, 1997; Sinclair et al, 2010). The wet season is identified by much lower BC concentrations.…”

Evidence of Recent Active Volcanism in the Balleny Islands (Antarctica) From Ice Core Records

“…The levels of SO 4 2− and MPC in the two intervals are above the detection threshold, suggesting an additional input of SO 4 2− and microparticles during these periods. In Antarctica, the 1994–1992 CE and 1984–1982 CE ice core layers have been linked to the well‐documented eruptions of Mount Pinatubo/Cerro Hudson (1991 CE; Cole‐Dai & Mosley‐Thompson, 1999; Hoffmann et al., 2020; Jiang et al., 2012; Osipov et al., 2014; Plummer et al., 2012; Schwanck et al., 2017; Thoen et al., 2018; Zhang et al., 2002) and El Chichón (1982 CE; Inoue et al., 2017; Jiang et al., 2012; Kohno et al., 1999; Plummer et al., 2012; Thoen et al., 2018; Traufetter et al., 2004), the two volcanic eruptions with the greatest SO 2 emissions worldwide of the 1977–2007 CE period (Shinohara, 2008). Therefore, we propose the excess of SO 4 2− and MPC identified during these periods (1994–1992 CE & 1984–1982 CE) were derived from the large low‐latitude (mid‐latitude) Pinatubo (Cerro Hudson) and El Chichón eruptions.…”

“…Additionally, two previously identified ice core horizons were targeted as examples of well‐dated volcanic events recorded in ice core layers. The 1994–1992 CE horizon for the Mount Pinatubo (Philippines, 15.13°N, 120.35°E) and Cerro Hudson (Chile, 45.92°S, 72.97°W) eruption (Pinatubo/Hudson) (1991 CE) (Cole‐Dai & Mosley‐Thompson, 1999; Hoffmann et al., 2020; Jiang et al., 2012; Osipov et al., 2014; Plummer et al., 2012; Schwanck et al., 2017; Thoen et al., 2018; Zhang et al., 2002) and the 1984–1982 CE horizon for the El Chichón eruption (1982 CE) (Mexico, 17.36°N, 93.22°W) (Jiang et al., 2012; Plummer et al., 2012; Thoen et al., 2018; Traufetter et al., 2004). Both eruptions are observed in younger ice core horizons because of the lagged deposition of volcanic sulfates over the Antarctic ice sheet after large low‐latitude eruptions (Cole‐Dai et al., 1997).…”

Particle‐Size Distributions and Solubility of Aerosol Iron Over the Antarctic Peninsula During Austral Summer

“…Major sources of atmospheric Fe deposited on West Antarctica and its adjacent offshore waters are believed to be the drylands of Australia and Patagonia (Gaiero, 2007; Gassó & Stein, 2007; Li et al, 2008; Pereira et al, 2004), occasional volcanic eruptions in South America (Browning et al, 2015), and local dust sources and biomass burning (Winton et al, 2014; Winton et al, 2016). Evidence in ice cores (Cataldo et al, 2013; Conway et al, 2015; McConnell et al, 2007; Schwanck et al, 2017) indicates the existence of dust and associated Fe deposited on West Antarctica. Iron from dust has also been found in snow on sea ice in the McMurdo Sound region (de Jong et al, 2013; Winton et al, 2014).…”