Journal cover Journal topic
Climate of the Past An interactive open-access journal of the European Geosciences Union
Journal topic

Journal metrics

Journal metrics

  • IF value: 3.174 IF 3.174
  • IF 5-year value: 3.841 IF 5-year 3.841
  • CiteScore value: 3.48 CiteScore 3.48
  • SNIP value: 1.078 SNIP 1.078
  • SJR value: 1.981 SJR 1.981
  • IPP value: 3.38 IPP 3.38
  • h5-index value: 42 h5-index 42
  • Scimago H index value: 58 Scimago H index 58
Discussion papers
https://doi.org/10.5194/cp-2018-167
© Author(s) 2018. This work is distributed under
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/cp-2018-167
© Author(s) 2018. This work is distributed under
the Creative Commons Attribution 4.0 License.

Research article 17 Dec 2018

Research article | 17 Dec 2018

Review status
This discussion paper is a preprint. It is a manuscript under review for the journal Climate of the Past (CP).

A large increase in the carbon inventory of the land biosphere since the Last Glacial Maximum: constraints from multi-proxy data

Aurich Jeltsch-Thömmes1,2, Gianna Battaglia1,2, Olivier Cartapanis2,3, Samuel L. Jaccard2,3, and Fortunat Joos1,2 Aurich Jeltsch-Thömmes et al.
  • 1Climate and Environmental Physics, Physics Institute, University of Bern, Bern, Switzerland
  • 2Oeschger Centre for Climate Change Research, University of Bern, Bern, Switzerland
  • 3Institute of Geological Sciences, University of Bern, Bern, Switzerland

Abstract. Atmospheric CO2 increased by about 90ppm across the transition from the Last Glacial Maximum (LGM) to the end of the preindustrial (PI) period. The contribution of changes in land carbon stocks to this increase remains uncertain. Estimates of the PI-LGM difference in land biosphere carbon inventory (∆land) range from −400 to +1,500GtC, based on upscaling of scarce paleo soil carbon or pollen data. A perhaps more reliable approach infers ∆land from reconstructions of the stable carbon isotope ratio in the ocean and atmosphere assuming isotopic mass balance with recent studies yielding ∆land values of about 300–400GtC. Surprisingly, however, earlier studies considered a mass balance for the ocean–atmosphere–land biosphere system only. Thereby, these studies neglect carbon exchange with sediments, weathering-burial flux imbalances, and the influence of the deglacial reorganization on the isotopic budgets. We show this neglect to significantly bias low deglacial ∆land in simulations using the Bern3D Earth System Model of Intermediate Complexity v.2.0s. We constrain ∆land to ∼850GtC (median estimate; 450 to 1250GtC 1σ range) by using reconstructed changes in atmospheric δ13C, marine δ13C, deep Pacific carbonate ion concentration, and atmospheric CO2 as observational targets in a Monte Carlo ensemble with half a million members. Sensitivities of the target variables to changes in individual deglacial carbon cycle processes are established from factorial simulations over the past 21,000 years with the Bern3D model. These are used in the Monte Carlo ensemble and provide forcing–response relationships for future model–model and model–data comparisons. Uncertainties in the estimate of ∆land remain considerable due to model and proxy data uncertainties. Yet, it is likely that ∆land is larger than 450GtC and highly unlikely that the carbon inventory in the land biosphere was larger for the LGM than during the recent preindustrial period.

Aurich Jeltsch-Thömmes et al.
Interactive discussion
Status: open (until 17 Feb 2019)
Status: open (until 17 Feb 2019)
AC: Author comment | RC: Referee comment | SC: Short comment | EC: Editor comment
[Subscribe to comment alert] Printer-friendly Version - Printer-friendly version Supplement - Supplement
Aurich Jeltsch-Thömmes et al.
Aurich Jeltsch-Thömmes et al.
Viewed  
Total article views: 412 (including HTML, PDF, and XML)
HTML PDF XML Total BibTeX EndNote
346 63 3 412 2 3
  • HTML: 346
  • PDF: 63
  • XML: 3
  • Total: 412
  • BibTeX: 2
  • EndNote: 3
Views and downloads (calculated since 17 Dec 2018)
Cumulative views and downloads (calculated since 17 Dec 2018)
Viewed (geographical distribution)  
Total article views: 233 (including HTML, PDF, and XML) Thereof 231 with geography defined and 2 with unknown origin.
Country # Views %
  • 1
1
 
 
 
 
Cited  
Saved  
No saved metrics found.
Discussed  
No discussed metrics found.
Latest update: 16 Jan 2019
Publications Copernicus
Special issue
Download
Short summary
A long standing question in climate science is concerned with which processes contributed to the increase in atmospheric CO2 after the last ice age. From the range of possible processes we try to constrain the change in carbon storage in the land biosphere. By combining ice-core and marine sediment data in a modeling framework we show that the carbon storage in the land biosphere increased largely after the last ice age. This will help to further understand processes at work in the Earth system.
A long standing question in climate science is concerned with which processes contributed to the...
Citation
Share