Archives for November 15, 2007

A revised Holocene sea-level curve for the southeast coast of New South Wales, Australia, is presented
based on a review of previously published geochronological results for fossil molluscs, organic-rich
mud, mangrove roots and fixed biological indicators. It is supplemented by new radiocarbon and amino acid
racemization-derived ages on fossil molluscs from transgressive sandsheet facies in back-barrier settings within
shallow incised valleys along the southern coast of New South Wales. This data base has been limited to fossils
with accurate descriptions of their facies associations and stratigraphic relationships to present mean sea
level. Results show that sea level during the Holocene marine transgression rose to between −15 and −11 m at
9400–9000 cal. yr BP. Sea level then rose to approximately −5 m by 8500 cal. yr BP and to approximately
−3.5 m between 8300 and 8000 cal. yr BP inundating shallow incised valleys resulting in the deposition of
shell-rich transgressive sandsheets within shallow incised bedrock valleys. Present sea level was attained
between 7900 and 7700 cal. yr BP, approximately 700–900 years earlier than previously proposed. Sea level
continued to rise to between +1 and +1.5 m between 7700 and 7400 cal. yr BP, followed by a sea-level highstand that lasted until about 2000 cal. yr BP followed by a gradual fall to present. A series of minor negative
and positive oscillations in relative sea level during the late-Holocene sea-level highstand appear to be superimposed over the general sea-level trend. However, the precise nature of the oscillations are difficult to quantify because of problems associated with accurately determining palaeotidal and wave regimes, climatic
conditions and the antecedent morphology of the shallow marine environments during the mid Holocene.

Holocene sea-level change on the southeast coast of Australia: a review

Craig R. Sloss
School of Earth & Environmental Sciences, University of Wollongong, Wollongong NSW 2522, Australia, c.r.sloss@massey.ac.nz

The Holocene, Vol. 17, No. 7, 999-1014 (2007)DOI: 10.1177/0959683607082415

Colin V. Murray-Wallace

School of Earth & Environmental Sciences, University of Wollongong, Wollongong NSW 2522, Australia

Brian G. Jones

School of Earth & Environmental Sciences, University of Wollongong, Wollongong NSW 2522, Australia

Melting Arctic Ocean sea ice may have been caused by a reversal in the ocean’s circulation that had been going on for about a decade, scientists from NASA and the University of Colorado said.

Rocky Mountain News: ‘Ocean circulation may contribute to warming’

A study of the world’s power stations has shown the extent to which developed countries produce more carbon dioxide per head than emerging economies.

Australians were found to be the world’s worst polluters per capita, producing five times as much carbon from generating power as China.

The US came second with eight tonnes of carbon per head – 16 times more than that produced by India.

BBC News website: ‘Australians named worst emitters’

Two events loom on the horizon that might settle the issue once and for all; one shaped by human hands, one entirely natural.

At Cern, the giant European physics facility, an experiment called Cloud is being constructed which will research the notion that cosmic rays can stimulate the formation of droplets and clouds. There may be some results within three or four years.

By then, observations suggest that the Sun’s output may have started to wane from its “grand maximum”.

If it does, and if Henrik Svensmark is right, we should then see cosmic rays increase and global temperatures start to fall; if that happens, he can expect to see a Nobel Prize and thousands of red-faced former IPCC members queuing up to hand back the one they have just received.

But if the Sun wanes and temperatures on our planet continue to rise, as the vast majority of scientists in the field believe, the solar-cosmic ray concept of global warming can be laid to eternal rest.

BBC News website: Sun and global warming: A cosmic connection?