FW: Ph.D research studentship in Palaeoceanography and Palaeoecol ogy of west equatorial Africa

[Katherine HARLE]

-----Original Message-----
From: F.Marret [mailto:f.marret at BANGOR.AC.UK] 
Sent: Saturday, January 26, 2002 1:47 AM
To: QUATERNARY at morgan.ucs.mun.ca
Subject: Ph.D research studentship in Palaeoceanography and
Palaeoecology of west equatorial Africa


Applications are invited for the following Ph.D. Research Studentship at
the School of Ocean Sciences, University of Wales (Bangor).

TITLE: Palaeoceanographic and palaeoenvironmental records of equatorial
climate since the Last Glacial Maximum from the Niger Fan

SUPERVISORS: Dr James Scourse and Dr Fabienne Marret

BACKGROUND

Investigating and understanding past global climate changes are of primary
importance in order to predict future climate. The need to establish
natural climate variability on millennial to decadal scales has increased
with the recent observation of the anthropogenic greenhouse effect.
Temperate to polar latitudes have been well documented from this point of
view, in particular in the Northern Hemisphere. However, it has recently
become clear that the tropics play a critical role in the heat transfer
from low to high latitudes. Therefore, any abrupt change in tropical
climate can have a dramatic consequence in northern latitudes.

Abrupt coolings, such as the Younger Dryas, between 11,000 and 10,000 14C
years ago, and the Little Ice Age which culminated between AD 1680 and
1750, are particularly well recorded in the Northern Hemisphere. Abrupt
climatic changes synchronous with these events, in particular the Younger
Dryas cooling, have been reported in the tropics, mainly expressed in terms
of changes in precipitation.  It is known that during the Last Glacial
Maximum the equatorial African region was drier than present; savannahs
were more widespread and rainforest vegetation survived locally in refuges.
However, information of past climate changes on a millennial to century
scale for this region is hampered by the paucity of high-resolution records
either on the continent or from the adjacent oceanic margin.

Deltas and fans adjacent to large rivers draining monsoonal regions have
been identified as important and under-exploited palaeoclimate archives.
Moreover, high sedimentation rates often characterise fan records from
equatorial regions. These sequences integrate the monsoonal signal through
fluctuations in past rainforest and savannah dynamics. A recently published
Integrated marine and terrestrial proxy record of oceanic and environmental
change from the Congo Fan indicates abrupt palaeodischarge events during
the last deglaciation (Marret et al. 2001). These have been interpreted in
terms of latitudinal migration of the Inter-Tropical Convergence Zone
(ITCZ). If this is the case, then similar fan accumulations in west-central
Africa should show similar signals phased in sequence with the Congo. We
have access to high-resolution core records from the Niger Fan which will
enable testing of this hypothesis.

OBJECTIVES AND WORK PROGRAMME

The aim of this proposal is to generate high-resolution palynological
records (pollen, freshwater algae, dinoflagellate cysts) from Niger Fan
cores covering the last 30,000 years. Cores recovered by German research
cruises (RV Meteor) to the research area are housed in the Department of
Geology, University of Bremen, Germany and the project will involve
sampling trips to Bremen. Closely-spaced samples will be processed for
palynological analysis, and analysed, in the School of Ocean Sciences. This
will be undertaken with the assistance of a supportive team consisting of
the project supervisor, Mr Brian Long (research technician) and Dr Fabienne
Marret (post-doctoral researcher) The age models for the core material, and
associated faunal (principally foraminiferal) and geochemical (stable
isotopes, biomarkers) data, will be generated in conjunction with
collaborators in Bremen and at the Netherlands Institute for Sea Research
in Texel, The age models will be based on AMS 14C chronologies.  The
project will be linked into a recently funded project (Leverhulme Trust) on
the Congo Fan to Dr Scourse and Dr Marret which will run from February 2002
to January 2005. The studentship will therefore be undertaken in the
context of a large and vibrant research group which is itself part of a
larger network of European scientists. Fabienne Marret will form an
important part of the supervisory team. The studentship may also involve a
preliminary cruise (Dakar to Cape Town) on the RV Marion Dufresne as part
of the IMAGES project in summer 2002 (application pending) to take new
cores from the Niger, Ogooué and Congo fans.

REFERENCE

MARRET, F., SCOURSE, J.D., VERSTEEGH, G., JANSEN, J.H.F. & SCHNEIDER, R.
2001. Integrated marine and terrestrial evidence for abrupt Congo River
palaeodischarge fluctuations during the last deglaciation. Journal of
Quaternary Science 16, 761-766.


ENQUIRIES

Enquiries to Dr James Scourse (01248 382876, j.scourse at bangor.ac.uk).
Further details are available on the School website:
http://www.sos.bangor.ac.uk/pgrad/phd/projects2002/index.htm

APPLICATIONS

Details of the application procedure and copies of the application form can
be obtained from the Postgraduate Admissions Secretary, Gillian Roberts
(01248 382846, oss089 at bangor.ac.uk). The deadline for applications is 4th
March.


--
Dr. Fabienne Marret   f.marret at bangor.ac.uk
School of Ocean Sciences  tel: (44) (0)1248 388123
University of Wales, Bangor  fax: (44) (0)1248 716367
Menai Bridge
Anglesey
LL59 5EY
UK
http://www.sos.bangor.ac.uk/
Celtic Sea Project
http://www.st-and.ac.uk/~www_sgg/personal/jre1link/index.htm