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Laser ablation ICPMS facility
established
A new analytical system has recently been commissioned. Based around
a 193nm excimer UV laser, the laser-ablation system was constructed
by colleagues at the Australian National University as part of a
long-running collaborative venture. Now coupled to the VIEPS/CODES
multi-collector ICP mass spectrometer, the system allows detailed
isotopic studies to be performed on samples using analytical volumes
a few tens of microns in diameter as opposed to the more traditional
analysis of ‘bulk’ samples. The potential applications
are wide-ranging and include dating of individual growth bands in
minerals, and tracing the complex magmatic evolution of minerals
growing in magma chambers, to analysis of climatic variations recorded
in speleothems.
For further details contact Dr
Jon Woodhead
The new laser ablation facility, with laser (left)
and MC-ICP mass spectrometer (centre)
School
of Earth Sciences Researchers Win ARC Linkage Grant
Congratulations to Prof AJ Gleadow, Dr BP Kohn, Dr
RW Brown and Mr MS Krochmal on winning a 2002 round 2 ARC Linkage
Grant titled: "Developing a fully automated analytical system
for the next generation of fission-track thermochronology".
This was one of only three Earth Science related Linkage Grants
funded in the country in this round.
The project will be conducted in partnership with
Autoscan Systems Pty Ltd and aims to develop a revolutionary new
generation of research tools for analysing the temperature history
of rocks in the upper several kilometres of the earth?s crust with
new opportunities for the commercialisation of the outcomes. The
approach will bring together and integrate several rapidly-developing
technologies at the forefront of international developments in this
field. The information obtained will contain vital clues about the
processes that operate within the crust, the evolution of its surface
environments over long periods of time, the long-term stability
of the ancient continental cores, and the formation of important
hydrocarbon and mineral resources.
More details can be found at the ARC website: www.arc.gov.au/funded_grants/selection_linkage_projects.htm
Water
on Mars? Or is it that Simple?
Ongoing research into the true role of water on Mars continued
in 2001 with the transfer to the University of Melbourne of the
unique research program ‘White Mars’, led by Dr Nick
Hoffman. In this program we look at the behaviour of carbon dioxide
on Mars, which is stable as a solid in the polecaps and as a gas
in the atmosphere. What is less well known is that liquid carbon
dioxide is stable in the subsurface of Mars. This has fundamental
consequences for the exploration of Mars and for its geological
evolution.
In August 2001, a major presentation to the NASA conference ‘Geophysical
Detection of Subsurface Water on Mars was used to point out that
liquid carbon dioxide is actually more likely and easier to access
than liquid water, given the extreme cold of Mars’ surface
and subsurface. For instance, the consequences of deep drilling
on Mars, in an attempt to find deposits of liquid water, is more
likely to hit a high pressure pocket of liquid carbon dioxide and
result in an uncontrolled blowout of carbon dioxide – endangering
or destroying the drilling equipment. This presentation sparked
widespread debate which concluded with a recognition that carbon
dioxide-based models could not be ruled out on the basis of any
available evidence and were therefore viable models for Mars.
The failure to account for liquid carbon dioxide in the subsurface
means that most models of Mars’ evolution are inappropriate
and misleading. Although there is plenty of ice on the Red Planet,
there may never have been very much liquid water, if any. Channel
features on the surface of Mars may well have been carved by boiling
clouds of exploding liquid carbon dioxide, suspending dust, sand,
and rocks as in a giant volcanic eruption on Earth, but flowing
downhill as a river of dust and gas.
Major research results announced during 2001 also included publication
of two new papers suggesting that the fill of the northern plains,
and of Hellas Basin could have taken place in a series of catastrophic
flows lubricated by liquid carbon dioxide, rather than exclusively
liquid water. These results challenge the conventional view that
Mars was once warmer and wetter than it is now, with clear consequences
for the chance of finding evidence of fossil life on Mars’
surface. Papers were also presented at another NASA conference in
March, exploring the thermal structure of the permafrost on a frozen
Mars, with CO2 in the subsurface; and on flow events in the Athabasca
Valles region of Elysium – where very young and well-preserved
flow events show paradoxical combinations of hot (volcanic?) and
cold (fluvial?) textures that can be reconciled with a CO2-rich
model.
Evidence
of more Extreme Storms and Wave Heights over the Northern Hemisphere
Oceans
Ian Simmonds and Kevin Keay have made an exhaustive study of surface
pressure synoptic charts for the Northern Hemisphere from the last
40 years. An overall aim of the work is to identify the nature of
atmospheric variability in that hemisphere, and to document and
understand the changes that have taken place over the second half
of the 20th century. A particular focus has been in determining
the rate at which mechanical energy is being transferred from the
atmosphere (via storms, etc.) to the ocean. This rate of energy
input determines the type and height of waves.
Ian and Kevin have shown that this rate of energy transfer has
increased over most parts of the Pacific and in the northern parts
of the Atlantic since the middle of last century. Using a simple
ocean model they have found that this would be expected to result
in greater mean heights of ocean waves in the northern oceans, a
situation consistent with the ocean-based observations of wave behaviour
over this time. The research shows that extratropical cyclonic systems
in the Northern Hemisphere have become much more intense during
the period. The two Figures shown illustrate how the number of very
intense cyclones have increased in both the Pacific and Atlantic
since 1958. At the same time the total number of cyclones in the
hemisphere have decreased. Taken together, the trends are consistent
with expectations from global warming, in the sense of a greater
number of extreme weather and oceanic events.
The work has just been published in the journal Meteorology
and Atmospheric Physics.
Ian
Simmonds wins inaugural AMOS Medal
Council of the Australian Meteorological and Oceanographic
Society is pleased to announce the award of the inaugural AMOS Medal
to Ian Simmonds of the School of Earth Sciences in the University
of Melbourne.
This new medal emphasizes leadership in meteorology, oceanography
and related fields in Australia, particularly through education
and development of young scientists, and through personal example
in research. It has been introduced by Council to complement the
existing awards of the Priestly Medal for personal excellence in
research and the Christopher Taylor Award for operational forecasting.
Ian completed a B.Sc. with first class honours at Monash followed
by a PhD at Flinders University. He held postdoctoral positions
with the Canadian Atmospheric Environmental Service in Montreal
and the Geophysical Fluid Dynamics Laboratory at Princeton before
returning as a research fellow to the former Department of Meteorology
of the University of Melbourne. He was appointed to a lectureship
in that Department in 1981, and in more recent years has played
a major, if not the major role, in the survival of meteorology as
an active discipline at Melbourne University, in spite of very severe
resource restrictions, the run down of staff and the absorption
of the Meteorology Group into Earth Sciences.
Ian's contributions to the advancement of meteorology and oceanography
in Australia over the last twenty years, through his teaching at
all levels, his graduate and postgraduate supervision and his personal
research and leadership, have been second to none. He has shown
genuine flair as an undergraduate teacher and his enthusiastic and
informed lecturing style and personal commitment have proved highly
attractive to students, whether as interludes that broadens degree
courses based on other subjects or as paths to honours and beyond.
Some 35 students have completed honours under his supervision. His
ability to attract and retain the interest of students of the highest
calibre and to set them on course to becoming successful leaders
and researchers in the atmospheric sciences is widely acknowledged
and the solid foundation provided by his teaching has enabled many
of these students to go on to extremely successful careers as operational
meteorologists with the Bureau of Meteorology and elsewhere. It
has also provided the basis for successful postgraduate studies
and eventual research and teaching careers for many others, 21 of
whom have completed higher degrees under his
supervision while a further 11 are currently under supervision.
In his own research, Ian has established himself nationally and
inter-nationally as a dynamical modeller of the atmosphere and oceans,
of general climatology and antarctic problems. Under his guidance,
Earth Sciences has developed comprehensive atmospheric and oceanic
modelling capabilities, developing and maintaining its own atmospheric
general circulation model for some 20 years, a feat unmatched by
any other Australian university. This modelling has in recent years
been broadened under Ian's direct leadership with the development
of advanced dynamical / thermodynamical models for snow cover and
sea ice. Special mention should be made of Ian's work on the use
of spectral models for data analysis and NWP, on modelling to understand
Antarctic processes, and the mechanisms through which local sea
surface temperature and soil moisture anomalies influence the persistence
and predictability of Australian climate variability. His interests
remain as wide ranging as ever, much of his work carried out and
published jointly with students.
Ian Simmonds has made significant contributions to current knowledge
in meteorology, climatology and oceanography, much of his work having
been done in collaboration with others who are often his students.
By his dedication to teaching of quality, his influence in these
fields, directly and through his students, will continue for years
to come. He is a fitting model for young students and scientists
and an excellent recipient for the inaugural AMOS Medal.
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