Project: Land-Ocean correlation of long Quaternary records from the southern hemisphere on orbital and sub-orbital timescales

Aim/background:

1. To determine the present state of knowledge on the nature and location of land and ocean records covering at least the last 40,000 years and determine and explain regional and temporal trends (in relation to tectonic, atmospheric, oceanographic and human influences), cyclicity (in relation to orbital and ice-volume forcing) and millennial-scale variability (in relation to ENSO, the Indian Ocean dipole, Heinrich events, Bond 'cycles', human impacts etc).
2. To identify critical gaps or areas of uncertainty and encourage and facilitate development of research proposals to fill them, particularly through involvement of the International Ocean Drilling Program (IODP) and the Continental Drilling Program (CDP).
3. To encourage and facilitate closer collaboration between marine and terrestrial researchers especially in examination of land and marine climate proxies within the same sediment cores, where possible.
4. To generate and compile a potentially exciting data set amenable to modelling as a means of better understanding controls over Australian and broader southern hemisphere and global climate change.
5. To provide evidence of changing vegetation and biodiversity directly through pollen and other biotic evidence and indirectly through dust and other inorganic components of sediment cores and to provide a firm base, chronologically and geographically, for other forms of biodiversity assessment.

It was considered that an independent project on the environmental history of the Australia and its relationships to other southern hemisphere continents would provide a firm and comprehensive historical basis for examination of the more recent evolution of the pattern and biodiversity of the landscape that could be applied by other related groups within the network and to the future informed management of this diversity.

Project:

Involvement has been facilitated by the project's CI, Peter Kershaw via his membership of the PAGES Scientific Steering Committee, Vice-president of the International Quaternary Association (INQUA) Palaeoclimate Commission (PALCOM), and PALCOM MIS11 and SQS working group on the Middle-Upper Pleistocene, as well as involvement in the INQUA Congress held in Cairns in July-August 07. The PALCOM working group on 'Marine Isotope Stage 11' is critical globally because the period is, in terms of orbital forcing' the most similar to the present interglacial and can provide a guide to future natural climate change. However, in Antarctica, as well as Australia, it generally marks a transition to a different climate state, providing complications that need to be addressed. The INQUA stratigraphic commission's working group on the 'Middle-Upper Pleistocene Boundary' aims at the resolution of differences emerging between records on land and the ocean with clear distinctions between the traditional Eemian and MIS5 in definition of the Last Interglacial period. Major geographical differences are also critical for understanding what is driving the onset of the Last Interglacial - the Antarctic, the tropics or the North Atlantic.

Due to distances involved between southern hemisphere continents, the number of involved researchers from northern hemisphere (particularly North America and Europe), the broad scope of the project and administrative requirements, it has not proved feasible to organize specific PASH2 meetings. However, symposia have been held at two relevant gatherings, the Southern Connections Conference in Adelaide, January 2007 and the INQUA Congress in Cairns

A follow up session, with the broader scope of the INQUA session, has been organised for the European Geosciences Union (EGU) in Vienna, April 2008.

Session CL7: 'Land-Atmosphere-Ocean linkages throughout the Quaternary' (Jan-Berend Stuut, Peter Kershaw, Isabel Cacho and Thorsten Kiefer)
'Interactions between ocean- and atmosphere processes are crucial for the identification of important feedbacks in climate change. Therefore, we need integrated studies of marine and terrestrial proxies and detailed land-sea correlations to establish the sensitivity and phase response of these different systems.
This session seeks to examine marine and terrestrial records on orbital to sub-millennial timescales, but with focus on different records from the same archive. We especially invite papers on sediment cores that establish links between land, atmosphere, and ocean by e.g., focusing on proxy records describing the different players derived from the same sediments.'
The possibility of publishing the papers gathered in this session in a special volume of a scientific journal with Quaternary emphasis will be explored.

Outcomes: