A comparison of the present and last interglacial periods in six Antarctic ice cores

Abstract

We compare the present and last interglacial periods as recorded in Antarctic water stable isotope records now available at various temporal resolutions from six East Antarctic ice cores: Vostok, Taylor Dome, EPICA Dome C (EDC), EPICA Dronning Maud Land (EDML), Dome Fuji and the recent TALDICE ice core from Talos Dome. We first review the different modern site characteristics in terms of ice flow, meteorological conditions, precipitation intermittency and moisture origin, as depicted by meteorological data, atmospheric reanalyses and Lagrangian moisture source diagnostics. These different factors can indeed alter the relationships between temperature and water stable isotopes. Using five records with sufficient resolution on the EDC3 age scale, common features are quantified through principal component analyses. Consistent with instrumental records and atmospheric model results, the ice core data depict rather coherent and homogenous patterns in East Antarctica during the last two interglacials. Across the East Antarctic plateau, regional differences, with respect to the common East Antarctic signal, appear to have similar patterns during the current and last interglacials. We identify two abrupt shifts in isotopic records during glacial inception at TALDICE and EDML, likely caused by regional sea ice expansion. These regional differences are discussed in terms of moisture origin and in terms of past changes in local elevation histories which are compared to ice sheet model results. Our results suggest that, for coastal sites, elevation changes may contribute significantly to inter-site differences. These elevation changes may be underestimated by current ice sheet models

A paleo-perspective on ocean heat content: Lessons from the Holocene and Common Era

“…in this core suggests that the planktonic record primarily represents changes in thermocline temperature/depth likely linked to climate change in the Southern Ocean (Kalansky et al, 2015). Antarctic ice cores (Masson-Delmotte et al, 2011;Mulvaney et al, 2012), terrestrial records (Verleyen et al, 2011) and Southern Ocean temperature reconstructions (Shevenell et al, 2011) show warming associated with the Younger Dryas and a near synchronous early HTM (~11.5-9 Ka) followed by a sharp cooling by ~8 ka. Based on the similarity with these records, it has been argued that the early Holocene temperature change in the thermostad originated in the southern high latitudes and was advected to the EEP thermostad by SAMW (Kalansky et al, 2015).…”

“…Based on opal accumulation records from cores in the South Atlantic and SW Pacific it has been argued that the SWW shifted southward after the Antarctic Cold Reversal (~ 13 Ka; (Anderson et al, 2009), and likely remained in a more poleward position until around 9-8 ka. This hypothesis is supported by different lines of paleoceanographic evidence including temperature records from Antarctic ice cores (e.g., (Masson-Delmotte et al, 2011;Mulvaney et al, 2012), reconstructions of Antarctic and Subantarctic SST (Bianchi and Gersonde, 2004;Kaiser et al, 2005;Pahnke and Sachs, 2006;Pahnke and Zahn, 2005;Shevenell et al, 2011) and sedimentary evidence for shifts in the precipitations belt in southern America (Bender et al, 2013;Lamy et al, 2010) (Fig. 4).…”

Limited Retreat of the Wilkes Basin Ice Sheet During the Last Interglacial

“…Solid colored lines depict data from Masson‐Delmotte et al. (2011) (running mean, thin black lines show original data), including the mean Holocene signature (horizontal dashed lines). The shaded curves illustrate the δ 18 O record after correction for surface elevation changes in a paleo‐ice‐sheet simulation (Sutter et al., 2019) using an elevation lapse rate of 0.8 K/100 m (Frezzotti et al., 2007) and a δ 18 O/temperature gradient of 0.7–1.4 permil/K.…”

Ice melt, sea level rise and superstorms: evidence from paleoclimate data, climate modeling, and modern observations that 2 °C global warming is highly dangerous

“…This distinctive spatial variation may help account for observed sea ice increasing in the Weddell and Ross Seas, while decreasing in the Amundsen and Bellingshausen Seas. Note also that the Weddell Sea and Ross Sea sectors are respectively the regions where the EDML and TALDICE Antarctic ice cores are suggestive of expanding sea ice (Masson-Delmotte et al, 2011) at end-Eemian time.…”