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.
Web site and data base development
The web site, with linkages to other relevant sites, can be seen at http://users.monash.edu.au/~pkershaw/
. It contains a near complete reference list, mapped location and metadata
for almost all terrestrial and marine/terrestrial records covering at
least the last 40,000 years in the Australian-Southeast Asian region.
Publications
A PAGES News issue, edited by Kershaw et al., provides a broad coverage
of scientific highlights for the hemisphere including ones that summarise
long term developments in the Antarctic and their importance to both
hemispheric and global changes in atmospheric and oceanic circulation
patterns, a contribution on land-ocean correlation that is noted as
a PASH2 contribution, and revelations from potentially very long terrestrial
records drilled by the International Continental Drilling Program whose
contributors include active PASH2 members.
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