Some of the key uncertainties in terms of future climate change is the sensitivity of the climate system to external forcing, uncertainties in key feedback factors (e.g. sea-ice/albedo, carbon cycle), and how ocean circulation may respond to forcings and to possible destabilisation of major ice sheets (Greenland and Antarctica).
Recent studies (e.g. Forest et al. 2006) indicate that the sensitivity of the climate system to a doubling of CO2 in the atmosphere lies between 1.5 and 4.5ºC with 3ºC as the most likely value. The upper bound for the sensitivity is less certain than the lower. One way of narrowing down this large uncertainty is to use the paleoclimate record, wherefrom it is possible to analyse sensitivity over a range of external forcings, boundary conditions and greenhouse gas levels. Entering detailed accounts of several glacial-interglacial cycles into this, allows for a wide range of observations for this purpose. With the availability of ice core GHG records over the last 670.000 years (Siegenthaler et al. 2005) and possibly the last 1 million years in the future, it will be important to provide records of the state of the ocean on comparable resolution. The aim of AMOCINT is to acquire marine sediment cores required for this purpose.
Main Objectives:
1. Survey and core sites for sampling of high sedimentation rate interglacial sections available to the Calypso coring system of the RV Marion Dufresne.
2. Conduct detailed site surveys for targeted IODP drilling to recover thick marine sediment sections over past interglacials at key locations for monitoring Atlantic Meridional Overturning Circulation (AMOC) variability.
3. Provide a feasibility study based on already available Calypso Cores and new cores taken within AMOCINT: Produce time series of North Atlantic circulation parameters with century scale resolution for the last interglacial and previous interglacials over the past 800.000 years and provide detailed comparisons with ice core records from Antarctica and Greenland.
Project Leader:
Professor Eystein Jansen
University of Bergen, Norway
Principal Investigators:
Dr. Catherine Kissel
CEA/CNRS/UVSQ, Gif-sur-Yvette, France
Dr. Silvia Nave
Instituto Nacional de Engenharia Tecnologia e Inovação (INETI), Alfragide, Portugal
Dr. Mara Weinelt
University of Kiel, Germany
Associated Partner:
Professor Henry Elderfield
University of Cambridge, United Kingdom
