Using new and existing ice core CO₂ data from 65 ∼ 30 ka a new chronology for CO₂ is established and synchronized with Greenland ice core records to study how high latitude climate change and the carbon cycle were linked during the last glacial period. Atmospheric CO₂ rose several thousand...
Ice core records show atmospheric methane mixing ratio and interpolar gradient varying with climate. Changes in wetland sources have been implicated as the basis for this observed variation in the record, but more recently, modeling studies suggest that changes in the CH₄ sink resulting from changes in sea surface temperature...
We have reconstructed chronology for the disturbed bottom parts of the GRIP and GISP2 ice cores using the combined paleoatmospheric records of CH₄ concentration and δ¹⁸O[subscript atm] in the trapped gases. Our reconstructed ages for basal ice samples are based on comparison of published measurements of CH₄ and δ¹⁸O[subscript atm]...
Atmospheric CO₂ records for the centennial scale cooling event 8200 years ago (8.2 ka event) may
help us understand climate-carbon cycle feedbacks under interglacial conditions, which are important for
understanding future climate, but existing records do not provide enough detail. Here we present a new CO₂
record from the Siple...
Full Text:
-termsofuse
Response of atmospheric CO2 to the abrupt
cooling event 8200 years ago
Jinho Ahn1, Edward J
Atmospheric CO₂ records for the centennial scale cooling event 8200 years ago (8.2 ka event) may
help us understand climate-carbon cycle feedbacks under interglacial conditions, which are important for
understanding future climate, but existing records do not provide enough detail. Here we present a new CO₂
record from the Siple...
Full Text:
MMaatteerriiaall
Response of atmospheric CO2 to the abrupt cooling event 8200 years
ago
Jinho Ahn1,*, Edward
Air trapped in glacial ice offers a means of
reconstructing variations in the concentrations of atmospheric
gases over time scales ranging from anthropogenic
(last 200 yr) to glacial/interglacial (hundreds of thousands of
years). In this paper, we review the glaciological processes by
which air is trapped in the ice and...
Radiocarbon measurements at ice margin sites and blue ice areas can potentially be used for ice dating, ablation rate estimates and paleoclimatic reconstructions. Part of the measured signal comes from in situ cosmogenic ¹⁴C production in ice, and this component must be well understood before useful information can be extracted...
We have measured the CO₂ concentration of air occluded during the last 40,000 years in the deep Siple Dome A (hereafter Siple Dome) ice core, Antarctica. The general trend of CO₂ concentration from Siple Dome ice follows the temperature inferred from the isotopic composition of the ice and is mostly...
Retreat of the Laurentide Ice Sheet (LIS) following the Last Glacial Maximum 21 000 yr BP affected regional to global climate and accounted for the largest proportion of sea level rise. Although the late Pleistocene LIS retreat chronology is relatively well constrained, its Holocene chronology remains poorly dated, limiting our...
Recent analysis of 38 globally distributed paleoclimatic records covering Marine Isotope Stage 3 (MIS 3) 60–26 ka demonstrated that the two leading empirical orthogonal functions (EOFs) explaining the data are the Greenland ice-core signal (“northern” signal) and the Antarctic ice-core signal (“southern” signal). Here singular spectral analysis (SSA) is used...