Project

climate dynamics; paleoclimate; isotopes; greenhouse gases; radionuclides; water cycle

Lead
Lay summary
A hierarchy of climate models is being used to provide quantitative information about processes of past and future climate change. Our model of reduced complexity, the Bern3D model, will be further developed by adding and testing modules of atmospheric energy balance, ocean sedimentation and marine ecosystems. With the coupling to a dynamic vegetation model Bern3D will become a comprehensive large-scale climate model. This model will be applied to a number of research questions: simulation of glacial-interglacial cycles and its coupling to the carbon cycle; novel paleoceanographic tracers and their geographical fingerprints during abrupt climate change; future climate change and carbon cycle feedback, in particular ocean acidification; modelling the methane and nitrogen cycles.We are involved in two deep drilling projects in Antarctica (Talos Dome) and Greenland (NEEM), as well as we plan future projects within the International Partnerships in ice Coring Sciences (IPICS. The greenhouse gas records from EPICA ice cores (EDC and EDML), and from Talos Dome will be completed in the next two years. An emphasis will be research on high-resolution windows to investigate millennial-scale variability during earlier ice ages, and natural greenhouse gas fluctuations during the interglacials. A major new focus will be the development of reliable experimental techniques to determine the isotopic composition of greenhouse gases (d13C of CO2 and CH4, and dD of CH4). This ambitious goal must be reached if we are to quantify processes of air enclosed in ice cores provide firstly an independent constraint on the time scale which is indispensable when these records are combined with other archives and secondly an independent novel paleothermometer for mean global ocean temperature. Continuous Flow Analysis will be performed in Greenland to measure the first continuous Holocene record. From these data we hope to be able to reconstruct northern hemispheric climate patterns over the last 10,000 years. The field deployment will also provide important information regarding an optimization of the equipment.We will utilize our radio tracer palette to contribute to national and international projects in hydrology, water resources management and reconstruction of climate change using groundwater. The noble gas tracer 85Kr, 37Ar and 39Ar are particularly suited to provide time information about groundwater processes. With 37Ar we have a tool to detect possible underground nuclear tests. The radiocarbon laboratory provides data for our own research in Alpine glacier retreat during the Holocene and environmental monitoring.

Direct link to Lay Summary

Last update: 21.02.2013

Number	Title	Start	Funding scheme

We were advised by the SNF to extend the duration and submit a proposal of two years duration. This project therefore covers a time that goes beyond the original detailed research plan [Science Plan 2007-2010, 2006]. It is also important to note that the Division of Climate and Environmental Physics at the University of Bern has achieved an important strategic milestone in its history by the establishment of a new chair of Experimental Climate Physics and the appointment of Prof. Hubertus Fischer on May 1, 2008. H. Fischer's research will be incorporated in this research proposal to enable and ensure intensive scientific interactions between the different research streams in our Division.A hierarchy of climate models is being used to provide quantitative information about processes of past and future climate change. Our model of reduced complexity, the Bern3D model, will be further developed by adding and testing modules of atmospheric energy balance, ocean sedimentation and marine ecosystems. With the coupling to a dynamic vegetation model Bern3D will become a comprehensive large-scale climate model. In the coming two years, this model will be applied to a number of research questions: (i) simulation of glacial-interglacial cycles and its coupling to the carbon cycle; (ii) novel paleoceanographic tracers and their geographical fingerprints during abrupt climate change; (iii) future climate change and carbon cycle feedback, in particular ocean acidification; (iv) modelling the methane and nitrogen cycles.Our research into climate reconstruction based on polar ice cores will be enhanced significantly in the coming two years as we are involved in two deep drilling projects in Antarctica (Talos Dome) and Greenland (NEEM), as well as the planning of future projects within the International Partnerships in Ice Coring Sciences (IPICS). The greenhouse gas records from the EPICA ice cores (EDC and EDML), and from Talos Dome will be completed in the next two years. An emphasis will be research on high-resolution windows to investigate millennial-scale variability during earlier ice ages, and natural greenhouse gas fluctuations during the interglacials. A major new focus of our research will be the development of reliable experimental techniques to determine the isotopic composition of greenhouse gases (d13C of CO2 and CH4, and dD of CH4). This ambitious goal must be reached if we are to quantify processes responsible for natural greenhouse gas changes. Changes of the elemental composition of air enclosed in ice cores provide firstly an independent constraint on the time scale which is indispensable when these records are combined with other archives and secondly an independent novel paleothermometer for mean global ocean temperature. Continuous Flow Analysis will be performed in the next two years in Greenland to measure the first continuous Holocene record. From these data we hope to be able to reconstruct northern hemispheric climate patterns over the last 10,000 years. The field deployment will also provide important information regarding an optimization of the equipment.We will utilize our radio tracer palette to contribute to national and international projects in hydrology, water resources management and reconstruction of climate change using groundwater. The noble gas tracers 85Kr, 37Ar and 39Ar are particularly suited to provide time information about groundwater processes. With 37Ar we have a tool to detect possible underground nuclear tests. The radiocarbon laboratory provides data for our own research in Alpine glacier retreat during the Holocene and environmental monitoring. In addition we offer dating services of organic samples for the Swiss research community.