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
Synthesis of proxy response to climate change in central Sweden during the late Holocene
Stockholm University, Faculty of Science, Department of Physical Geography and Quaternary Geology.
Stockholm University, Faculty of Science, Department of Physical Geography and Quaternary Geology.
Stockholm University, Faculty of Science, Department of Physical Geography and Quaternary Geology.
Stockholm University, Faculty of Science, Department of Physical Geography and Quaternary Geology.
(English)Article in journal (Other academic) In Progess
Abstract [en]

Biological and geochemical proxies from two lakes and two peat sites in central Sweden are used to test if the inferred climate change can be connected to previously reported temperature anomalies, inferred from stacked pollen mean annual and mean July temperatures mainly in Fennoscandia, during the late Holocene. We show that the reported temperature deviations (lower temperatures between 3800-3000, higher temperatures between 3000-500, and lower temperatures again between 500-50 cal yr BP), can be related to recorded changes in the investigated proxies. These periods correspond to changes inferred from two of the sites; in one of the lakes the reconstructed evaporation and input ratio (E/I) show a high ratio from a dry and likely warmer climate, with decreased importance of precipitation input, and vice versa for a low ratio, and, from one of the peat humification records. Beyween 600-300 cal yr BP magnetic susceptibility increased in a lacustrine sediment record and water table rose according to peat records. The proxies from central Sweden seem to support a late Holocene temperature maximum around ca 2000 cal yr BP, although this is speculative since it is represented by a few samples only.

National Category
Geology
Research subject
Quarternary Geology
Identifiers
URN: urn:nbn:se:su:diva-36882OAI: oai:DiVA.org:su-36882DiVA: diva2:290879
Available from: 2010-01-28 Created: 2010-01-28 Last updated: 2010-01-29Bibliographically approved
In thesis
1. Late Holocene humidity variability in central Sweden
Open this publication in new window or tab >>Late Holocene humidity variability in central Sweden
2010 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

The aim of this thesis was to reconstruct humidity variability in central Sweden during the late Holocene. A multi-proxy approach was used to infer humidity changes as recorded in a lake and a mire. Age-models were constructed based on radiocarbon dating and the Askja-1875 tephra. Stable isotopes (δ18O and δ13C) on Chara spp encrustations and Pisidium spp mollusc shells and carbon content were analysed in the lake record, whereas peat stratigraphy, humification, testate amoebae assemblages, C/N ratio and stable isotopes (δ13C and δ15N) were analysed in the mire record. Stable isotopes (δ2H and δ18O) on lake water showed that Lake Blektjärnen responded to changes in the balance between evaporation and input water (E/I ratio). A high E/I ratio results from a dry and probably warmer climate during which evaporation and atmospheric equilibration likely enrich lake water in 18O and 13C, respectively, and vice versa for a low E/I ratio. The relatively high Chara δ18O and δ13C values between ca 4400 and 4000 cal yr BP thus suggest relatively dry and likely warm conditions, whereas depleted values suggest wetter and probably cooler conditions between ca 4000 and 3000 cal yr BP. Again, drier and probably warmer conditions were inferred from the relatively enriched δ18O values between ca 2500 and 1000 cal yr BP, and depleted δ18O values were recorded between ca 1000 and 50 cal yr BP indicating wetter and likely cooler conditions. The results from the mire mainly indicated vegetation succession, however, the changes inferred at ca 2600 and 1000 cal yr BP could have been triggered by climate change. This study shows that the proxies responded sensitively to humidity changes in the investigated archives allowing for reconstruction of climate change in central Sweden during late Holocene.

Place, publisher, year, edition, pages
Stockholm: Department of Physical Geography and Quaternary Geology, Stockholm University, 2010. 60 p.
Series
Dissertations from the Department of Physical Geography and Quaternary Geology, ISSN 1653-7211 ; 20
Keyword
humidity change, stable isotopes, Chara spp, Pisidium spp, testate amoebae assemblages, humification, C/N ratio, late Holocene, central Sweden
National Category
Geology
Research subject
Quarternary Geology
Identifiers
urn:nbn:se:su:diva-36884 (URN)978-91-7155-929-6 (ISBN)
Public defence
2010-03-05, De Geersalen, Geovetenskapens hus, Svante Arrhenius väg 14, Stockholm, 13:00 (English)
Opponent
Supervisors
Note
At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 1: Submitted. Paper 3: Accepted. Paper 5: In progress.Available from: 2010-02-11 Created: 2010-01-28 Last updated: 2010-10-07Bibliographically approved

Open Access in DiVA

No full text

Search in DiVA

By author/editor
Andersson, SofiaBergman, JonasWastegård, StefanSchoning, Kristian
By organisation
Department of Physical Geography and Quaternary Geology
Geology

Search outside of DiVA

GoogleGoogle Scholar

urn-nbn

Altmetric score

urn-nbn
Total: 92 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