High-resolution analyses of an early Holocene climate event may imply decreased solar forcing as an important climate trigger | Health & Environmental Research Online (HERO)

HERO ID

1286875

Reference Type

Journal Article

Title

High-resolution analyses of an early Holocene climate event may imply decreased solar forcing as an important climate trigger

Author(s)

Bjorck, S; Muscheler, R; Kromer, B; Andresen, CS; Heinemeier, Jan; Johnsen, SJ; Conley, D; Koc, N; Spurk, M; Veski, S

Year

2001

Is Peer Reviewed?

Yes

Journal

Geology
ISSN: 0091-7613

Publisher

Geological Society of America (GSA)

Location

United States (USA)

Volume

29

Issue

12 (December 2001)

Page Numbers

1107-1110

Abstract

Early Holocene lacustrine, tree-ring, ice-core, and marine records reveal that the Northern Hemisphere underwent a short cooling event at 10 300 calendar yr B.P. (9100 (super 14) C yr B.P.). The records were compared on a common high-resolution time scale and show that the event lasted less than 200 yr, with a cooling peak of 50 yr, and the event coincides with a distinct Holocene thermohaline disturbance recognized in the North Atlantic Ocean. In spite of well-known freshwater forcings at the time of the event, the negligible difference between the modeled Delta (super 14) C record, based on the GISP2 (Greenland Ice Sheet Project 2) (super 10) Be data, and the measured values, does not allow for detectable Delta (super 14) C changes related to global ocean ventilation. We can, however, show that the onset of the cooling coincides with the onset of one of the largest Holocene (super 10) Be flux peaks. This finding may imply that the climate system is more sensitive to solar-related changes than previously thought and that such changes may be an important underlying mechanism for sub-Milankovitch climate variability.

Keywords

pollen; miospores; C-14; climate change; absolute age; orbital forcing; paleoclimatology; Cenozoic; Lake Starvatn; Milankovitch theory; causes; calibration; climate forcing; palynomorphs; cooling; tephrochronology; GISP2; C-14/C-12; beryllium; lower Holocene; lake sediments; stable isotopes; dates; marine sediments; Saksunarvatn Ash; ice cores; metals; carbon; Faeroe Islands; proxies; alkaline earth metals; isotopes; Be-10; tree rings; sediments; Atlantic Ocean Islands; Quaternary; correlation; radioactive isotopes; microfossils; lacustrine environment; high-resolution methods; Holocene