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Full-Text Articles in Physical Sciences and Mathematics
Radiocarbon In Corals From The Cocos (Keeling) Islands And Implications For Indian Ocean Circulation, Q Hua, Colin D. Woodroffe, Scott Smithers, M Barbetti, David Fink
Radiocarbon In Corals From The Cocos (Keeling) Islands And Implications For Indian Ocean Circulation, Q Hua, Colin D. Woodroffe, Scott Smithers, M Barbetti, David Fink
Faculty of Science - Papers (Archive)
Annual bands of a Porites coral from the Cocos (Keeling) Islands, eastern Indian Ocean, were analysed by radiocarbon for 1955–1985 AD. A rapid oceanic response of the site to bomb 14C is found, with a maximum D14C value of 132% in 1975. This value is considerably higher than those for the northwestern Indian Ocean, suggesting that surface waters reaching Cocos are not derived from the Arabian Sea. Instead, D14C values for Cocos and those for Watamu (Kenya) agree well over most of the study interval, suggesting that the South Equatorial Current carries 14C-elevated water rather than 14C-depleted water westward across …
Macrochannels And Their Significance For Flood-Risk Minimisation, West Dapto, New South Wales, E. L. Roper, Ivars Reinfelds, Gerald C. Nanson
Macrochannels And Their Significance For Flood-Risk Minimisation, West Dapto, New South Wales, E. L. Roper, Ivars Reinfelds, Gerald C. Nanson
Faculty of Science - Papers (Archive)
A prominent characteristic of streams draining catchments in West Dapto, New South Wales, are well developed macrochannels that have formed within alluvial terraces in mid-catchment zones. A detailed hydraulic modelling study using HEC-RAS, HEC-GeoRAS and Arcview GIS indicates that these macrochannels are scaled to accommodate high magnitude floods. They offer a significant degree of natural protection from flood events up to and in excess of 100 years recurrence interval, essentially by operating as 'bankfull' channels during such events. Macrochannel landforms can be clearly distinguished and mapped on fine-scale digital elevation models (DEMs) and other GIS data sources such as rectified …
Comparisons Between Sciamachy And Ground-Based Ftir Data For Total Columns Of Co, Ch4, Co2 And N2o, B Dils, M De Maziere, T Blumenstock, M Buchwitz, R De Beek, Nicholas B. Jones, David W. Griffith, P Demoulin, A G Frankenberg, H Duchatelet, Hans Fast
Comparisons Between Sciamachy And Ground-Based Ftir Data For Total Columns Of Co, Ch4, Co2 And N2o, B Dils, M De Maziere, T Blumenstock, M Buchwitz, R De Beek, Nicholas B. Jones, David W. Griffith, P Demoulin, A G Frankenberg, H Duchatelet, Hans Fast
Faculty of Science - Papers (Archive)
Total column amounts of CO, CH4, CO2 and N2O retrieved from SCIAMACHY nadir observations in its near-infrared channels have been compared to data from a ground-based quasi-global network of Fourier-transform infrared (FTIR) spectrometers. The SCIAMACHY data considered 5 here have been produced by three different retrieval algorithms, WFM-DOAS (version 0.4, 0.41 for CH4), IMAP-DOAS (version 0.9) and IMLM (version 5.5) and cover the January to December 2003 time period. Comparisons have been made for individual data, as well as for monthly averages. To maximize the number of reliable coincidences that satisfy the temporal and spatial collocation criteria, the 10 SCIAMACHY …
Illuminating Southeast Asian Prehistory : New Archaeological And Paleoanthropological Frontiers For Luminescence Dating, Richard G. Roberts, Michael J. Morwood, Kira E. Westaway
Illuminating Southeast Asian Prehistory : New Archaeological And Paleoanthropological Frontiers For Luminescence Dating, Richard G. Roberts, Michael J. Morwood, Kira E. Westaway
Faculty of Science - Papers (Archive)
Since the explorations of Alfred Russel Wallace and Eugène Dubois in the nineteenth century, Southeast Asia has been one of the world's focal points for studies of biogeography and biodiversity, human evolution and dispersal, environmental change, and the spread of culture, farming, and language. Yet despite its prominence, reliable chronologies are not available for many of the critical archaeological, evolutionary, and environmental turning points that have taken place in the region during the last 1.5 million years. In this paper, we discuss some of these chronological problems and describe how luminescence dating may help overcome them. "Luminescence dating" is a …
An Automated Gis Method For Modeling Relative Wave Exposure Within Complex Reef-Island Systems: A Case Study Of The Great Barrier Reef, Marjetta L. Puotinen
An Automated Gis Method For Modeling Relative Wave Exposure Within Complex Reef-Island Systems: A Case Study Of The Great Barrier Reef, Marjetta L. Puotinen
Faculty of Science - Papers (Archive)
Patterns of wave energy play a significant role in shaping the long-term structure of coral reef communities worldwide. For example, sections of reefs have been shown to vary greatly in morphology (dominant size class, growth form) as coral colonies adapt in response to local-scale differences in the wave heights typically experienced. These differences result in zonation (crest, lagoon, and slope), producing characteristic growth forms and species assemblages that vary in their vulnerability to damage from waves (Done 1993). Those communities experiencing the greatest typical wave energy align themselves parallel to the water flow, adopt stream-lined forms and are usually smaller …
Evidence For Altitude-Dependent Photolysis-Induced 18o Isotopic Fractionation In Stratospheric Ozone, Vanessa E. Haverd, Geoffrey C. Toon, David W. Griffith
Evidence For Altitude-Dependent Photolysis-Induced 18o Isotopic Fractionation In Stratospheric Ozone, Vanessa E. Haverd, Geoffrey C. Toon, David W. Griffith
Faculty of Science - Papers (Archive)
We present vertical profiles of 18O fractionations in ozone, measured by balloon-borne infrared remote sensing between 15 and 40 km. The magnitudes of the 16O16O18O (668O3) and 16O18O16O (686O3) fractionations are 13.5 +/- 2.7% and 7.7 +/- 2.2%, averaged over the 20-35 km altitude range, in good agreement with previous atmospheric measurements by mass spectrometry and both infrared and far infrared remote sensing spectroscopy. We use our fractionation profiles, together with known fractionation effects of the ozone formation reaction, to deduce …
Rotational Effects In The Band Oscillator Strengths And Predissociation Linewidths For The Lowest 1pi U X 1sigma + G Transitions Of N2, V. E. Haverd, B.R. Lewis, S.T. Gibson, G. Stark
Rotational Effects In The Band Oscillator Strengths And Predissociation Linewidths For The Lowest 1pi U X 1sigma + G Transitions Of N2, V. E. Haverd, B.R. Lewis, S.T. Gibson, G. Stark
Faculty of Science - Papers (Archive)
A coupled-channel Schrödinger equation (CSE) model of photodissociation, which includes the effects of all interactions between the , , and and the and states, is employed to study the effects of rotation on the lowest- band oscillator strengths and predissociationlinewidths. Significant rotational dependences are found which are in excellent agreement with recent experimental results, where comparisons are possible. New extreme-ultraviolet (EUV)photoabsorption spectra of the key transition of are also presented and analyzed, revealing apredissociationlinewidth peaking near . This behavior can be reproduced only if the triplet structure of the state is included explicitly in the CSE-model calculations, with a spin-orbit …