Ice Core Records of Atmospheric CO ₂ Around the Last Three Glacial Terminations

Abstract

Air trapped in bubbles in polar ice cores constitutes an archive for the reconstruction of the global carbon cycle and the relation between greenhouse gases and climate in the past. High-resolution records from Antarctic ice cores show that carbon dioxide concentrations increased by 80 to 100 parts per million by volume 600 ± 400 years after the warming of the last three deglaciations. Despite strongly decreasing temperatures, high carbon dioxide concentrations can be sustained for thousands of years during glaciations; the size of this phase lag is probably connected to the duration of the preceding warm period, which controls the change in land ice coverage and the buildup of the terrestrial biosphere.

Anomalous flow below 2700 m in the EPICA Dome C ice core detected using δ<sup>18</sup>O of atmospheric oxygen measurements

“…It should be noted that the CO 2 concentration increase appears to lag slightly the increase in δD ratio of the ice by 800±600 years at the start of the last glacial termination (Monnin et al, 2001). Studies of the Vostok record found similar lags of around 1000 years at the start of glacial terminations (Caillon et al, 2003;Fischer et al, 1999;Petit et al, 1999). One exception to the exclusion of early glaciations is the minimum before 14.3, which occurs during the early cooling phase between interglacial 15 and glacial stage 14.…”

A reconstruction of atmospheric carbon dioxide and its stable carbon isotopic composition from the penultimate glacial maximum to the last glacial inception

“…However, and on the Talos Dome (blue diamonds) ice cores (EDC3 synchronized TALDICE-1a age scale) are shown (this study). CO 2 data previously measured on the Vostok ice core are plotted with grey downward pointing triangles after conversion to the EDC3 age scale (Lüthi et al, 2008) for the Petit et al (1999), and with light grey stars for the Fischer et al (1999) CO 2 data. Previous data by Lourantou et al (2010b) are presented with yellow, upward pointing triangles.…”

A corrosive concoction: The combined effects of ocean warming and acidification on the early growth of a stony coral are multiplicative

“…Concentrations of atmospheric CO 2 naturally fluctuate between below 200 up to around 280 ppm from glacial to interglacial cycles (Fischer et al 1999), but have risen dramatically in the last 200 years from the 280 ppm post-glacial and pre-industrial levels to modern concentrations of approximately 380 ppm (Feely et al, 2004). Ocean surface water pH has already fallen by 0.1 unit, compared to pre-industrial times, which equals a 30% increase of the H + -concentration (Caldeira and Wickett, 2003).…”