TY  - JOUR
A1  - Bakke, Jostein
A1  - Lie, Øyvind
A1  - Heegaard, Einar
A1  - Dokken, Trond
A1  - Haug, Gerald H.
A1  - Birks, Hilary H.
A1  - Dulski, Peter
A1  - Nilsen, Trygve
T1  - Rapid oceanic and atmospheric changes during the Younger Dryas cold period
N2  - The Younger Dryas event, which began approximately 12,900 years ago, was a period of rapid cooling in the Northern Hemisphere, driven by large-scale reorganizations of patterns of atmospheric and oceanic circulation(1-3). Environmental changes during this period have been documented by both proxy-based reconstructions(3) and model simulations(4), but there is currently no consensus on the exact mechanisms of onset, stabilization or termination of the Younger Dryas(5-8). Here we present high-resolution records from two sediment cores obtained from Lake Krakenes in western Norway and the Nordic seas. Multiple proxies from Lake Krakenes are indicative of rapid alternations between glacial growth and melting during the later Younger Dryas. Meanwhile, reconstructed sea surface temperature and salinity from the Nordic seas show an alternation between sea-ice cover and the influx of warm, salty North Atlantic waters. We suggest that the influx of warm water enabled the westerly wind systems to drift northward, closer to their present-day positions. The winds thus brought relatively warm maritime air to Northern Europe, resulting in rising temperatures and the melting of glaciers. Subsequent input of this fresh meltwater into the ocean spurred the formation of sea ice, which forced the westerly winds back to the south, cooling Northern Europe. We conclude that rapid alternations between these two states immediately preceded the termination of the Younger Dryas and the permanent transition to an interglacial state.
Y1  - 2009
UR  - http://www.nature.com/ngeo/index.html
U6  - https://doi.org/10.1038/ngeo439
SN  - 1752-0894
ER  - 
TY  - GEN
A1  - Battarbee, Richard W.
A1  - Lamb, Henry F.
A1  - Bennett, Keith
A1  - Edwards, Mary
A1  - Bjune, Anne E.
A1  - Kaland, Peter E.
A1  - Berglund, Björn E.
A1  - Lotter, André F.
A1  - Seppä, Heikki
A1  - Willis, Kathy J.
A1  - Herzschuh, Ulrike
A1  - Birks, Hilary H.
T1  - John Birks
BT  - pioneer in quantitative palaeoecology
T2  - The Holocene
N2  - We describe the career of John Birks as a pioneering scientist who has, over a career spanning five decades, transformed palaeoecology from a largely descriptive to a rigorous quantitative science relevant to contemporary questions in ecology and environmental change. We review his influence on students and colleagues not only at Cambridge and Bergen Universities, his places of primary employment, but also on individuals and research groups in Europe and North America. We also introduce the collection of papers that we have assembled in his honour. The papers are written by his former students and close colleagues and span many of the areas of palaeoecology to which John himself has made major contributions. These include the relationship between ecology and palaeoecology, late-glacial and Holocene palaeoecology, ecological succession, climate change and vegetation history, the role of palaeoecological techniques in reconstructing and understanding the impact of human activity on terrestrial and freshwater ecosystems and numerical analysis of multivariate palaeoecological data.
T3  - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 420 
KW  - climate change
KW  - ecosystem history
KW  - Holocene
KW  - late-glacial
KW  - numerical data analysis
KW  - palaeoecology
KW  - palaeolimnology
Y1  - 2018
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-404544
ER  -