TY  - JOUR
AU  - Andrews JT, Belt S. T.
PY  - 2009//
TI  - Sea ice and marine climate variability for NW Iceland/Denmark Strait over the last 2000 cal. yr BP
JO  - The Holocene
SP  - 775
EP  - 784
VL  - 19
IS  - 5
N2  - MD99-2263 is a 46 cm box core collected from Djupall, a trough that cuts across the NW Iceland Shelf and ends above Denmark Strait. We provide a multiproxy record that   documents changes in the regional marine climate over the last ~1700 yr. The depth/age model is based on seven calibrated radiocarbon dates on mollusk shells and on 210Pb and 137Cs. Sediment accumulation rates were variable (0.2--0.8 mm/yr) but increased dramatically ~AD 1500. Grain-size, magnetic   properties, quantitative mineral composition of the <2 mm sediment fraction, benthic foraminiferal composition, benthic and planktic {Delta}18O ratios, and   abundances/fluxes of the sea ice biomarker IP25 were determined. To better compare the various proxies, 12 of the critical climate proxies were co-ordinated into 100-yr/sample time series, which were examined by Principal  Component Analysis. The 1st axis explained 49% of the variance and the 2nd axis explained an additional 17%. The variables most strongly associated with the 1st axis were sediment properties (phi mean, clay%) and the sea ice biomarker. Mineralogical indicators of drift ice rafting, such as the presence of quartz and potassium- and sodium-feldspars, coincide with the IP25 biomarker data and show an increase after AD 1200, but high values of quartz and some feldspars  also occurred between c. AD 300 and 900 with pronounced minima between AD 900 and 1100. Overall, our data suggest a simple two-fold division in climate   conditions over the last 1700 yr, with the major change occurring c. AD 1200. In the last few decades, conditions have reverted towards those experienced  prior to AD 1200.
SN  - 0959-6836
UR  - http://dx.doi.org/10.1177/0959683609105302
N1  - exported from refbase (http://publi.ipev.fr/polar_references/show.php?record=1965), last updated on Wed, 03 Jul 2024 13:55:55 +0200
ID  - AndrewsJT2009
ER  -