Multidecadal to millennial marine climate oscillations across the Denmark Strait (~ 66° N) over the last 2000 cal yr BP

Abstract

Abstract. In the area of Denmark Strait (∼ 66 • N), the two modes of the North Atlantic Oscillation (NAO) and Arctic Oscillation (AO) are expressed in changes of the northward flux of Atlantic water and the southward advection of polar water in the East Iceland current. Proxies from marine cores along an environmental gradient from extensive to little or no drift ice, capture low frequency variations over the last 2000 cal yr BP. Key proxies are the weight% of calcite, a measure of surface water stratification and nutrient supply, the weight% of quartz, a measure of drift ice transport, and grain size. Records from Nansen and Kangerlussuaq fjords show variable ice-rafted debris (IRD) records but have distinct mineralogy associated with differences in the fjord catchment bedrock. A comparison between cores on either side of the Denmark Strait (MD99-2322 and MD99-2269) show a remarkable millennial-scale similarity in the trends of the weight% of calcite with a trough reached during the Little Ice Age. However, the quartz records from these two sites are quite different. The calcite records from the Denmark Strait parallel the 2000 yr Arctic summer-temperature reconstructions; analysis of the detrended calcite and quartz data reveal significant multi-decadal-century periodicities superimposed on a major environmental shift occurring ca. 1450 AD.

Variability in the Northern North Atlantic and Arctic Oceans Across the Last Two Millennia: A Review

“…These results are also consistent with the trends seen in diatom‐based April sea ice cover in the southern Denmark Strait (Figure f; Miettinen et al, ). Another record from the eastern side of the Denmark Strait shows a step increase in quartz content (indicator of drift ice) at ~1,600–2,000 compared to the earlier half of the last millennium (Andrews & Jennings, ). Yet, other records from the cores in SE Greenland Fjords indicate variable source for the recorded drift ice through the last 2,000 years (Andrews et al, ).…”

Quantifying Provenance and Transport Pathways of Holocene Sediments From the Northwestern Greenland Margin

“…In addition, the study of late Quaternary sediments from the Baffin Bay have provided important information to distinguish (i) variations in the provenance of detrital particles (Andrews et al, , ; Sheldon et al, ; Simon, ; Simon et al, , ), (ii) climate and atmospheric changes in source regions and surrounding land masses (e.g., Andrews & Jennings, 2014; Thomas et al, ), and (iii) variations in sediment propagation and ocean current trajectories (e.g., Georgiadis et al, ; Jennings et al, ; Simon, ). In this regard, the present study proposes new mineralogical and geochemical data from three marine sediment cores recovered from the Upernavik cross‐shelf trough (AMD14‐204), Melville Bay cross‐shelf trough (AMD14‐210), and Kane Basin (AMD14‐Kane2B).…”

Timber Logging in Central Siberia is the Main Source for Recent Arctic Driftwood

“…Mineralogy (X-Ray Diffraction, qXRD) was previously analyzed at about 100-yr intervals and at 30-yr resolution for the last 2 cal ka B.P. (Andrews and Jennings, 2014). IP 25 data were obtained with a mean 100-yr resolution for the past 8 cal ka B.P.…”