Don said "You can't say that sea levels wont rise"
the following courtesy of
Volume 38 Number 24, 19 December 1997
"Study challenges theory on Greenhouse sea level
Dr Robert Haworth
A Department of Geography and Planning study has uncovered extensive
marine fossil deposits along Sydney's southern sea cliffs providing
evidence that sea levels around the city were at least two metres
higher 4000-6000 years ago than they are today.
The study, conducted by geographers Dr Robert Haworth and Dr Robert
challenges the belief held by many scientists that the earth's oceans
now at their highest levels in at least 6000 years. The findings also
important implications for the enhanced Greenhouse debate by suggesting
that natural climatic and sea level variations have been largely
overlooked in the debate's modelling assumptions.
The study was published recently by Marine Geology, the leading inter-
national journal of marine tectonic science.
During an investigation of sandstone cliff faces in southern Sydney,
Dr Haworth and Dr Baker discovered that massive rockfalls had covered
and preserved 4000-year-old fossils and Aboriginal engravings in a
geological "time capsule".
The geographers found extensive fossil shellcrust of common intertidal
organisms under the fallen rock, consistently preserved two metres
higher than the present range of these marine species. The fossils
were then dated using Carbon-14 dating methods. According to Dr Baker,
the heights and dates of the fossils were consistent with fossil
deposits found in 1989 in a sea cave at Valla, on the North Coast
of NSW, by UNE geologist Associate Professor Peter Flood.
"It is extremely unlikely that there would have been the same amount
of uplift in two parts of the coast so far apart in what is considered
one of the most tectonically stable coastlines in the world," said
Dr Baker. "These findings offer solid evidence that the sea level was
substantially higher a few thousand years ago along the NSW coastline
and that it dropped sharply over a short period of time."
He said that further studies of the fossil shellfish sequence were
still required to develop one of the first fine detail graphs of sea
level fluctuations in the immediate past.
"It appears that there has been much more movement in sea levels
and possible associated climate change than we had previously
believed," said Dr Baker.
He added that the higher sea levels meant that many low-lying areas
of Sydney would have been submerged as recently as 4000 years ago.
"Botany Bay was probably lapping around the edges of the Sydney Cricket
Ground and Centennial Park," said Dr Baker.
"Areas such as Bankstown, on the Georges River, and Homebush, on the
Parramatta River, would have been large, shallow inland bays. In
other words, until a few thousand years ago, the Olympic site would
have been underwater!"
The geographers said the study's findings cast new light on the Global
Warming debate, adding that any discussion on global warming should be
put into the context of natural climatic fluctuations. "The point that
there have probably been continuous short-term changes in the sea level
has largely been ignored within discussions on global warming,"
said Dr Robert Haworth. "How can we be certain that present trends are
natural or human-induced when the background has been perpetually
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