Blar i Bergen Open Research Archive på forfatter "Dokken, Trond Martin"
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A brief history of climate – the northern seas from the Last Glacial Maximum to global warming
Eldevik, Tor; Risebrobakken, Bjørg; Bjune, Anne Elisabeth; Andersson, Carin; Birks, Harry John Betteley; Dokken, Trond Martin; Drange, Helge; Glessmer, Mirjam Sophia; Li, Camille; Nilsen, Jan Even Øie; Otterå, Odd Helge; Richter, Kristin; Skagseth, Øystein (Peer reviewed; Journal article, 2014-12)The understanding of climate and climate change is fundamentally concerned with two things: a well-defined and sufficiently complete climate record to be explained, for example of observed temperature, and a relevant ... -
Consistent fluctuations in intermediate water temperature off the coast of Greenland and Norway during Dansgaard-Oeschger events
Sessford, Evangeline; Jensen, Mari Fjalstad; Tisserand, Amandine Aline; Muschitiello, Francesco; Dokken, Trond Martin; Nisancioglu, Kerim Hestnes; Jansen, Eystein (Peer reviewed; Journal article, 2019-11-01)Rapid warmings epitomize the Dansgaard-Oeschger events that are recorded in Greenland ice cores and imprinted in ocean sediment cores. While the abrupt climate changes appear connected to perturbations in sea ice and ocean ... -
Dansgaard-Oeschger and Heinrich event temperature anomalies in the North Atlantic set by sea ice, frontal position and thermocline structure
Pedro, J.B.; Andersson, Carin; Vettoretti, G.; Voelker, A.H.L.; Waelbroeck, C.; Dokken, Trond Martin; Jensen, Mari Fjalstad; Rasmussen, S.O.; Sessford, Evangeline; Jochum, M.; Nisancioglu, Kerim Hestnes (Journal article; Peer reviewed, 2022)We use eighteen timescale-synchronised near-surface temperature reconstructions spanning 10–50 thousand years before present to clarify the regional expression of Dansgaard-Oeschger (D-O) and Heinrich (H) events in the ... -
Dansgaard-Oeschger cycles: Interactions between ocean and sea ice intrinsic to the Nordic seas
Dokken, Trond Martin; Nisancioglu, Kerim Hestnes; Li, Camille; Battisti, David Stephen; Kissel, Catherine (Peer reviewed; Journal article, 2013-09)Dansgaard-Oeschger (D-O) cycles are the most dramatic, frequent, and wide-reaching abrupt climate changes in the geologic record. On Greenland, D-O cycles are characterized by an abrupt warming of 10 ± 5°C from a cold ... -
High resolution benthic Mg/Ca temperature record of the intermediate water in the Denmark Strait across D-O stadial-interstadial cycles
Sessford, Evangeline; Tisserand, Amandine Aline; Risebrobakken, Bjørg; Andersson, Carin; Dokken, Trond Martin; Jansen, Eystein (Peer reviewed; Journal article, 2018)Dansgaard‐Oeschger (D‐O) climate instabilities that took place during Marine Isotope Stage 3 are connected to changes in ocean circulation patterns and sea ice cover. Here we explore in detail the configuration of the water ... -
Inception of the Northern European Ice Sheet due to contrasting ocean and insolation forcing
Risebrobakken, Bjørg; Dokken, Trond Martin; Otterå, Odd Helge; Jansen, Eystein; Gao, Yongqi; Drange, Helge (Peer reviewed; Journal article, 2007-01)About 115,000 years ago the last interglacial reached its terminus and nucleation of new ice sheet growth was initiated. Evidence from the northernmost Nordic Seas indicate that the inception of the last glacial was related ... -
Independent tephrochronological evidence for rapid and synchronous oceanic and atmospheric temperature rises over the Greenland stadial-interstadial transitions between ca. 32 and 40 ka b2k
Berben, Sarah M.P.; Dokken, Trond Martin; Abbott, Peter M.; Cook, Eliza; Sadatzki, Henrik; Simon, Margit Hildegard; Jansen, Eystein (Journal article; Peer reviewed, 2020)Understanding the dynamics that drove past abrupt climate changes, such as the Dansgaard-Oeschger (DO) events, depends on combined proxy evidence from disparate archives. To identify leads, lags and synchronicity between ... -
Insolation and Glacial Meltwater Influence on Sea‐Ice and Circulation Variability in the Northeastern Labrador Sea During the Last Glacial Period
Griem, Lisa; Voelker, Antje H.L.; Berben, Sarah Miche Patricia; Dokken, Trond Martin; Jansen, Eystein (Journal article; Peer reviewed, 2019)The variable amounts of ice rafted debris (IRD) and foraminifers in North Atlantic sediments are related to the abrupt, millennial‐scale alteration from Greenland stadials to interstadials during the last glacial period ... -
Mg/Ca ratios in the planktonic foraminifer Neogloboquadrina pachyderma (sinistral) in the northern North Atlantic/Nordic Seas
Meland, Marius Yddal; Jansen, Eystein; Elderfield, Henry; Dokken, Trond Martin; Olsen, Are; Bellerby, Richard G. J. (Peer reviewed; Journal article, 2006-06-15)In core top samples in the Nordic Seas, Mg/Ca ratios of N. pachyderma (sin.) are generally consistent with previous high-latitude calibration data but do not reflect the modern calcification temperature gradient from 2ºC ... -
A multi-decadal record of oceanographic changes of the past ~165 years (1850-2015 AD) from Northwest of Iceland
Simon, Margit Hildegard; Muschitiello, Francesco; Tisserand, Amandine Aline; Olsen, Are; Moros, Matthias; Perner, Kerstin; Bårdsnes, Siv Tone; Dokken, Trond Martin; Jansen, Eystein (Journal article; Peer reviewed, 2020)Extending oceanographic data beyond the instrumental period is highly needed to better characterize and understand multi-decadal to centennial natural ocean variability. Here, a stable isotope record at unprecedented ... -
Refining benthic foraminiferal Mg/Ca-temperature calibrations using core-tops from the western tropical Atlantic: Implication for paleotemperature estimation
Tisserand, Amandine Aline; Dokken, Trond Martin; Waelbroeck, Claire; Gherardi, Jeanne-M.; Scao, Vincent; Fontanier, Christophe; Jorissen, Frans (Peer reviewed; Journal article, 2013-04)Benthic foraminiferal Mg/Ca has been shown to have great potential as a proxy for reconstructing deep water temperatures. However, the exact relationship between Mg uptake in benthic foraminifera and temperature is still ... -
Sea ice variability in the southern Norwegian Sea during glacial Dansgaard-Oeschger climate cycles
Sadatzki, Henrik; Dokken, Trond Martin; Berben, Sarah Miche Patricia; Muschitiello, Francesco; Stein, Ruediger; Fahl, Kirsten; Menviel, Laurie; Timmermann, Axel; Jansen, Eystein (Peer reviewed; Journal article, 2019-03-06)The last glacial period was marked by pronounced millennial-scale variability in ocean circulation and global climate. Shifts in sea ice cover within the Nordic Seas are believed to have amplified the glacial climate ... -
Tephra horizons identified in the western North Atlantic and Nordic Seas during the Last Glacial Period: Extending the marine tephra framework
Rutledal, Sunniva; Berben, Sarah Miche Patricia; Dokken, Trond Martin; Bilt, Willem van der; Cederstrøm, Jan Magne; Jansen, Eystein (Journal article; Peer reviewed, 2020)Geochemically distinct volcanic ash (tephra) deposits are increasingly acknowledged as a key geochronological tool to synchronize independent paleoclimate archives. Recent advances in the detection of invisible (crypto) ...