Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Remobilization of Old Permafrost Carbon to Chukchi Sea Sediments During the End of the Last Deglaciation
Stockholm University, Faculty of Science, Department of Environmental Science and Analytical Chemistry.
Stockholm University, Faculty of Science, Department of Environmental Science and Analytical Chemistry.ORCID iD: 0000-0002-9611-0815
Stockholm University, Faculty of Science, Department of Geological Sciences. Aarhus University, Denmark.ORCID iD: 0000-0002-4866-3204
Stockholm University, Faculty of Science, Department of Environmental Science and Analytical Chemistry. National Research Council, Italy.ORCID iD: 0000-0002-1686-3375
Show others and affiliations
Number of Authors: 142019 (English)In: Global Biogeochemical Cycles, ISSN 0886-6236, E-ISSN 1944-9224, Vol. 33, no 1, p. 2-14Article in journal (Refereed) Published
Abstract [en]

Climate warming is expected to destabilize permafrost carbon (PF-C) by thaw-erosion and deepening of the seasonally thawed active layer and thereby promote PF-C mineralization to CO2 and CH4. A similar PF-C remobilization might have contributed to the increase in atmospheric CO2 during deglacial warming after the last glacial maximum. Using carbon isotopes and terrestrial biomarkers (Delta C-14, delta C-13, and lignin phenols), this study quantifies deposition of terrestrial carbon originating from permafrost in sediments from the Chukchi Sea (core SWERUS-L2-4-PC1). The sediment core reconstructs remobilization of permafrost carbon during the late Allerod warm period starting at 13,000 cal years before present (BP), the Younger Dryas, and the early Holocene warming until 11,000 cal years BP and compares this period with the late Holocene, from 3,650 years BP until present. Dual-carbon-isotope-based source apportionment demonstrates that Ice Complex Deposit-ice- and carbon-rich permafrost from the late Pleistocene (also referred to as Yedoma)-was the dominant source of organic carbon (66 +/- 8%; mean +/- standard deviation) to sediments during the end of the deglaciation, with fluxes more than twice as high (8.0 +/- 4.6 g.m(-2).year(-1)) as in the late Holocene (3.1 +/- 1.0 g.m(-2).year(-1)). These results are consistent with late deglacial PF-C remobilization observed in a Laptev Sea record, yet in contrast with PF-C sources, which at that location were dominated by active layer material from the Lena River watershed. Release of dormant PF-C from erosion of coastal permafrost during the end of the last deglaciation indicates vulnerability of Ice Complex Deposit in response to future warming and sea level changes.

Place, publisher, year, edition, pages
2019. Vol. 33, no 1, p. 2-14
Keywords [en]
past carbon cycling, permafrost, climate change feedback, carbon isotope, coastal erosion, deglaciation
National Category
Earth and Related Environmental Sciences
Identifiers
URN: urn:nbn:se:su:diva-166611DOI: 10.1029/2018GB005969ISI: 000458243500001OAI: oai:DiVA.org:su-166611DiVA, id: diva2:1299200
Available from: 2019-03-26 Created: 2019-03-26 Last updated: 2025-02-07Bibliographically approved
In thesis
1. Remobilization of terrestrial carbon across temporal and spatial scales deduced from the Arctic Ocean sediment record
Open this publication in new window or tab >>Remobilization of terrestrial carbon across temporal and spatial scales deduced from the Arctic Ocean sediment record
2021 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Arctic warming is expected to trigger large-scale environmental change including remobilization of terrestrial organic carbon (terrOC). Permafrost and peatland systems contain more than twice as much carbon as the atmosphere, and may upon destabilization expose large amounts of their carbon to microbial decomposition and release climate-forcing greenhouse gases (GHG). Remobilization of terrOC also causes lateral leakage of organic matter via Arctic rivers with further translocated organic matter degradation and GHG release, while a remainder is exported to the Arctic Ocean and re-deposited in sediments. Arctic Ocean sediments are thus receptors of terrOC remobilization for a large part of the circum-Arctic drainage basin, and offer an archive to study past terrOC remobilization, e.g. during warming periods of the last deglaciation.

This thesis investigates terrOC in Arctic Ocean sediments to study OC remobilization from permafrost and other terrestrial systems across temporal and spatial scales. As a first – historical – approach, permafrost OC remobilization and degradation during past warming episodes are studied using OC, dual-isotope source apportionment (13C-OC; 14C-OC) and terrestrial biomarkers (lignin phenols, long-chained n-alkanes and n-alkanoic acids) in glacial-cycle sediment cores from the Siberian continental margin. The results reveal that permafrost systems were highly vulnerable to OC release throughout past warming events, foremost during the Bølling–Allerød (14.7-12.9 kyr before present - BP) warming period and the early Holocene climate optimum (11.7-7.5 kyr BP). The sediment record shows that climate warming of about 1°C and 1.5°C (Northern Hemisphere) then triggered large-scale thawing of mostly coastal permafrost and permafrost soils in the Siberian hinterland. These results are consistent with the hypothesis that large-scale permafrost OC remobilization may have contributed to the observed rise in atmospheric CO2 during the last deglaciation, and thereby stresses the importance of permafrost thawing in the light of anthropogenic climate change. 

The second – spatial – study angle in this thesis investigates the contemporary Earth system and studies terrOC remobilization from permafrost and other terrestrial sources using terrOC accumulation in surface sediments of the circum-Arctic shelf seas. This includes establishment and application of the Circum-Arctic Sediment Carbon Database (CASCADE), which is a data collection of thousands of observations of OC, 13C-OC, 14C-OC and terrestrial biomarkers from the published literature and yet-unpublished records. This offers the opportunity to study large-scale remobilization of terrOC in the circum-Arctic by integrating input from terrOC sources over large areas. Mass accumulation rates of the different terrOC sources (by 210Pb dating and dual-isotope source apportionment of OC) reveal that surface (incl. permafrost) soils remobilize more than twice as much terrOC as coastal erosion of old Pleistocene permafrost. Furthermore, vulnerabilities of terrOC stocks to large-scale remobilization are discussed, which suggests permafrost soils to be the most vulnerable terrOC pool to remobilization by climate warming. 

This thesis highlights the vulnerability of terrOC stores to Arctic warming over time and space, and thus contributes to a better understanding of climate-carbon couplings in the Earth system.

Place, publisher, year, edition, pages
Stockholm: Department of Environmental Science, Stockholm University, 2021. p. 48
Keywords
Arctic, climate change, permafrost, carbon, paleoclimate
National Category
Earth and Related Environmental Sciences
Research subject
Applied Environmental Science
Identifiers
urn:nbn:se:su:diva-192062 (URN)978-91-7911-480-0 (ISBN)978-91-7911-481-7 (ISBN)
Public defence
2021-05-28, De Geersalen, Geovetenskapens hus, Svante Arrhenius väg 14, online via Zoom, public link is available at the department website, Stockholm, 10:00 (English)
Opponent
Supervisors
Available from: 2021-05-05 Created: 2021-04-12 Last updated: 2025-02-07Bibliographically approved

Open Access in DiVA

No full text in DiVA

Other links

Publisher's full text

Authority records

Martens, JannikWild, BirgitPearce, ChristofTesi, TommasoAndersson, AugustO'Regan, MattJakobsson, MartinSköld, MartinGustafsson, Örjan

Search in DiVA

By author/editor
Martens, JannikWild, BirgitPearce, ChristofTesi, TommasoAndersson, AugustO'Regan, MattJakobsson, MartinSköld, MartinGustafsson, Örjan
By organisation
Department of Environmental Science and Analytical ChemistryDepartment of Geological SciencesDepartment of Mathematics
In the same journal
Global Biogeochemical Cycles
Earth and Related Environmental Sciences

Search outside of DiVA

GoogleGoogle Scholar

doi
urn-nbn

Altmetric score

doi
urn-nbn
Total: 162 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf