S
Sigfus J Johnsen
Researcher at University of Copenhagen
Publications - 209
Citations - 50997
Sigfus J Johnsen is an academic researcher from University of Copenhagen. The author has contributed to research in topics: Ice core & Ice sheet. The author has an hindex of 94, co-authored 209 publications receiving 47832 citations. Previous affiliations of Sigfus J Johnsen include Niels Bohr Institute & Denver Federal Center.
Papers
More filters
Journal ArticleDOI
The 20-yr cycle in Greenland ice core records
W. D. Hibler,Sigfus J Johnsen +1 more
TL;DR: In this paper, the authors examined characteristic oscillations in Greenland ice core oxygen isotope records and found that the strongest spectral peak occurs at a period of 20±0.5 yr with a statistically significant amplitude.
Journal ArticleDOI
Retrieving the paleoclimatic signal from the deeper part of the EPICA Dome C ice core
Jean-Louis Tison,M. de Angelis,Geneviève C Littot,Eric W. Wolff,Hubertus Fischer,Margareta Hansson,Matthias Bigler,Roberto Udisti,Anna Wegner,Jean Jouzel,Barbara Stenni,Sigfus J Johnsen,Valérie Masson-Delmotte,Amaelle Landais,Vladimir Ya. Lipenkov,L. Loulergue,J. M. Barnola,Jean-Robert Petit,Barbara Delmonte,G. Dreyfus,Dorthe Dahl-Jensen,Geoffroy Durand,Bernhard Bereiter,Adrian Schilt,Renato Spahni,K. Pol,Reginald Lorrain,Roland Souchez,Denis Samyn +28 more
TL;DR: In this article, the bottom 60 m of the EPICA (European Project for Ice Coring in Antarctica) Dome C ice core from central Antarctica is divided into two distinct facies: the lower 12 m showing visible solid inclusions and the upper 48 m which are referred to as the "basal clean ice facies".
Journal ArticleDOI
Rapid oscillations in Vostok and GRIP Ice Cores
TL;DR: In this article, the spectral properties of climatic times series derived from two recent ice cores in Greenland and East Antarctica were investigated, and it was found that the signals behave in a similar way in the high frequency part of their spectra.
Journal ArticleDOI
Links between MIS 11 millennial to sub-millennial climate variability and long term trends as revealed by new high resolution EPICA Dome C deuterium data - A comparison with the Holocene
K. Pol,Maxime Debret,Valérie Masson-Delmotte,Emilie Capron,Olivier Cattani,Gabrielle Dreyfus,Gabrielle Dreyfus,S. Falourd,Sigfus J Johnsen,Jean Jouzel,Amaelle Landais,Bénédicte Minster,Barbara Stenni +12 more
TL;DR: In this paper, a detailed deuterium measurements conducted on the EPICA Dome C ice core, Antarctica, with a ~50 year temporal resolution was used to describe the Antarctic temperature variability during the long interglacial period occurring ~400 thousand years before the present (Marine Isotopic Stage, MIS 11).
Journal ArticleDOI
Speculations about the next glaciation
TL;DR: In this article, a spectacular 10'8O16O ratio drop in precipitation indicative of rapid cooling occurred at Camp Century, Greenland, 89,500 y.a. The timing is based upon an assumption of δ periodicity being constant in time.