Journal cover Journal topic
Climate of the Past An interactive open-access journal of the European Geosciences Union
doi:10.5194/cp-2016-119
© Author(s) 2016. This work is distributed
under the Creative Commons Attribution 3.0 License.
Research article
30 Nov 2016
Review status
This discussion paper is under review for the journal Climate of the Past (CP).
A 21,000 year record of organic matter quality in the WAIS Divide ice core
Juliana D'Andrilli1,2, Christine M. Foreman1,2, Michael Sigl3, John C. Priscu4, and Joseph R. McConnell3 1Dept. Chemical and Biological Engineering, Montana State University, Bozeman, Montana, USA
2Center for Biofilm Engineering, Montana State University, Bozeman, 59717, USA
3Division of Hydrologic Science, Desert Research Institute, Reno, 89512, USA
4Dept. of Land Resources & Environmental Science, Montana State University, Bozeman, 59717, USA
Abstract. Englacial ice contains a significant reservoir of organic material (OM), preserving a chronological record of materials from Earth's past. Here, we investigate if OM quality surveys in ice core research can provide paleoecological information on the dynamic nature of our Earth through time. Temporal trends in OM quality from the early Holocene extending back to the Last Glacial Maximum (LGM) of the West Antarctic Ice Sheet Divide (WD) ice core were measured by fluorescence spectroscopy. Fluorescent intensity fluctuations and PARAFAC modelling of fluorescent OM from the LGM (27.0–18,0 kyrs BP; before present 1950), through the last deglaciation (LD; 18.0–11.5 kyrs BP), to the early to mid-Holocene (11.5–6.0 kyrs BP) provided evidence of different types of OM chemical species in the WD ice core over 21.0 kyrs. Two proteinaceous PARAFAC components (C1 and C2) were characteristic of fluorescent OM prevailing in all climate periods, suggesting a strong signature of labile microbial OM. A humic-like component (C3), characteristic of terrestrial and marine OM fluorescence, was only observed during the Holocene, suggesting that recalcitrant OM may be an ecological marker of warmer climates. Fluctuations in WD ice core OM fluorescence over 21.0 kyrs BP may be driven by environmental changes at the source, and potentially its interaction with the atmosphere. We suggest that fluorescent OM signatures observed during the LGM were the result of greater continental dust loading of microbially derived proteinaceous material in a drier climate, with lower marine influences when sea ice extent was higher, and continents had more expansive tundra cover. As the climate warmed, the OM quality record in the WD ice core changed, reflecting shifts in carbon productivity as a result of global ecosystem response.

Citation: D'Andrilli, J., Foreman, C. M., Sigl, M., Priscu, J. C., and McConnell, J. R.: A 21,000 year record of organic matter quality in the WAIS Divide ice core, Clim. Past Discuss., doi:10.5194/cp-2016-119, in review, 2016.
Juliana D'Andrilli et al.
Juliana D'Andrilli et al.
Juliana D'Andrilli et al.

Viewed

Total article views: 112 (including HTML, PDF, and XML)

HTML PDF XML Total Supplement BibTeX EndNote
92 20 0 112 2 0 1

Views and downloads (calculated since 30 Nov 2016)

Cumulative views and downloads (calculated since 30 Nov 2016)

Viewed (geographical distribution)

Total article views: 112 (including HTML, PDF, and XML)

Thereof 111 with geography defined and 1 with unknown origin.

Country # Views %
  • 1

Saved

Discussed

Latest update: 21 Jan 2017
Publications Copernicus
Download
Short summary
Climate driven trends in organic matter (OM) character over 21.0 kyrs, preserved in Antarctic ice cores, were measured by fluorescence spectroscopy. Microbially derived OM character prevailed throughout the record; however, fluctuations in OM type were observed, reflecting environmental shifts as a result of global ecosystem response in a warming climate. Terrestrial/marine OM signatures were detected in warm climates. Thus, ice cores contain significant chronological OM records of Earth’s past.
Climate driven trends in organic matter (OM) character over 21.0 kyrs, preserved in Antarctic...
Share