A tentative reconstruction of the last interglacial and glacial inception in Greenland based on new gas measurements in the Greenland Ice Core Project (GRIP) ice core

Amaelle Landais (1, 2) , Jérôme J Chappellaz (3) , Marc Delmotte (1, 4) , Jean Jouzel (1, 2) , Thomas Blunier (5) , Christine Bourg (1) , Nicolas Caillon (1, 2) , Stéphane Cherrier (1) , Bruno Malaize (1, 6) , Valérie Masson-Delmotte (1, 2) , Dominique Raynaud (3) , Jakob Schwander (5) , Jorgen Peder Steffensen (7)

1 LSCE - Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette]
2 GLACCIOS - Glaces et Continents, Climats et Isotopes Stables
3 LGGE - Laboratoire de glaciologie et géophysique de l'environnement
4 ICOS-RAMCES - ICOS-RAMCES
5 CEP - Climate and Environmental Physics [Bern]
6 EPOC - Environnements et Paléoenvironnements OCéaniques
7 UCPH - University of Copenhagen = Københavns Universitet

The disturbed stratigraphy of the ice in the lowest 10% of the Greenland GRIP ice core prevents direct access to climatic information older than 110 kyr. This is especially regretful since this period covers the previous interglacial corresponding to marine isotopic stage 5e (MIS 5e, 130-120 kyr B.P.). Here we present a tentative reconstruction of the disturbed GRIP chronology based on the succession of globally well mixed gas parameters. The GRIP d 18 O ice chronological sequence is obtained by comparing a new set of d 18 O of atmospheric O 2 and CH 4 measurements from the bottom section of the GRIP core with their counterpart in the Vostok Antarctic profiles. This comparison clearly identifies ice from the penultimate glacial maximum (MIS 6, 190-130 kyr B.P.) in the GRIP core. Further it allows rough reconstruction of the last interglacial period and of the last glacial inception in Greenland which appears to lay its Antarctic counterpart. Our data suggest that while Antarctica is already entering into a glaciation, Greenland is still experiencing a warm maximum during MIS 5e.

Mots clés: 1040 Geochemistry: Isotopic composition/chemistry; 1827 Hydrology: Glaciology (1863); 3344 Meteorology and Atmospheric Dynamics: Paleoclimatology; KEYWORDS: interglacial; ice cap; firn

Domaines: Océan, Atmosphère; Interfaces continentales, environnement

Amaelle Landais, Jérôme J Chappellaz, Marc Delmotte, Jean Jouzel, Thomas Blunier, et al.. A tentative reconstruction of the last interglacial and glacial inception in Greenland based on new gas measurements in the Greenland Ice Core Project (GRIP) ice core. Journal of Geophysical Research, 2003, 108 (D18), ⟨10.1029/2002JD003147⟩. ⟨hal-03105301⟩