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Articles 1 - 11 of 11
Full-Text Articles in Physical Sciences and Mathematics
Coral Reefs And Reef Islands Of The Amirantes Archipelago, Western Indian Ocean, Sarah Hamylton, Tom Spencer, Annelise B. Hagan
Coral Reefs And Reef Islands Of The Amirantes Archipelago, Western Indian Ocean, Sarah Hamylton, Tom Spencer, Annelise B. Hagan
Faculty of Science - Papers (Archive)
No abstract provided.
Spatial Modelling Of Benthic Cover Using Remote Sensing Data In The Aldabra Lagoon, Western Indian Ocean, Sarah Hamylton, Tom Spencer, A Hagan
Spatial Modelling Of Benthic Cover Using Remote Sensing Data In The Aldabra Lagoon, Western Indian Ocean, Sarah Hamylton, Tom Spencer, A Hagan
Faculty of Science - Papers (Archive)
Spatially explicit ecological modelling was used to predict the distribution of 4 benthic components (live coral, carbonate sand, macroalgae and dead coral) inside the Aldabra lagoon, southern Seychelles, western Indian Ocean. Both classic ordinary least-squares and spatial autoregression techniques were carried out on a field data set of 774 spatially referenced records and 3 satellite remote sensing images to define an empirical relationship between local environmental conditions (water depth and water level variation) and benthic cover. This relationship was then used to generate a synoptic model of the spatial cover and distribution of each benthic component at the landscape (i.e. …
Accordion Vs. Quantum Tectonics: Insights Into Continental Growth Processes From The Paleozoic Of Eastern Gondwanan, Jonathan C. Aitchison, Solomon Buckman
Accordion Vs. Quantum Tectonics: Insights Into Continental Growth Processes From The Paleozoic Of Eastern Gondwanan, Jonathan C. Aitchison, Solomon Buckman
Faculty of Science - Papers (Archive)
The Early Paleozoic Lachlan Fold Belt of eastern Australia is widely regarded as an ancient convergent plate margin beneath which paleo-Pacific (Panthalassic) oceanic lithosphere was continuously subducted. It is cited as the type example of a retreating accretionary orogeny. However, sandstone compositions, the sedimentological nature and timing of chert accumulation and overall stratigraphic architecture are not necessarily consistent with this model. We suggest an alternative explanation for growth of Gondwanan continental margin. Oceanic lithosphere outboard of the passive Gondwana continental margin was subducted beneath an extensive intra-oceanic island arc that now crops out as an allochthonous element (Macquarie arc) within …
Long-Range Correlations In Fourier Transform Infrared, Satellite, And Modeled Co In The Southern Hemisphere, Olaf Morgenstern, Guang Zeng, Stephen W. Wood, John Robinson, Dan Smale, Clare Paton-Walsh, Nicholas B. Jones, David W. T Griffith
Long-Range Correlations In Fourier Transform Infrared, Satellite, And Modeled Co In The Southern Hemisphere, Olaf Morgenstern, Guang Zeng, Stephen W. Wood, John Robinson, Dan Smale, Clare Paton-Walsh, Nicholas B. Jones, David W. T Griffith
Faculty of Science - Papers (Archive)
We use Fourier transfonn infrared ground-based measurements and satellite and model data to assess long-range correlations in tropospheric carbon monoxide. We fmd that CO columns measured in New Zealand correlate well with those measured in Antarctica, if a transport-related lag is taken into account. The model suggests that this long-range correlation is part of a mode of anomalous CO comprising almost the whole southern extratropics, which is linked to biomass burning in the southern continents. No such mode is modeled for the Northern Hemisphere. The area of long-range correlations maximizes for the southern subtropical Pacific, which is identified as an …
Riverine Source Of Arctic Ocean Mercury Inferred From Atmospheric Observations, Jenny A. Fisher, Daniel J. Jacob, Anne L. Soerensen, Helen M. Amos, Alexandra Steffen, Elsie M. Sunderland
Riverine Source Of Arctic Ocean Mercury Inferred From Atmospheric Observations, Jenny A. Fisher, Daniel J. Jacob, Anne L. Soerensen, Helen M. Amos, Alexandra Steffen, Elsie M. Sunderland
Faculty of Science - Papers (Archive)
Methylmercury is a potent neurotoxin that accumulates in aquatic food webs. Human activities, including industry and mining, have increased inorganic mercury inputs to terrestrial and aquatic ecosystems. Methylation of this mercury generates methylmercury, and is thus a public health concern. Marine methylmercury is a particular concern in the Arctic, where indigenous peoples rely heavily on marine-based diets. In the summer, atmospheric inorganic mercury concentrations peak in the Arctic, whereas they reach a minimum in the northern mid-latitudes. Here, we use a global three-dimensional ocean–atmosphere model to examine the cause of this Arctic summertime maximum. According to our simulations, circumpolar rivers …
Atmospheric Carbon Dioxide Retrieved From The Greenhouse Gases Observing Satellite (Gosat): Comparison With Ground-Based Tccon Observations And Geos-Chem Model Calculations, A Cogan, H Boesch, R Parker, L Feng, Paul Palmer, J-F Blavier, Nicholas M. Deutscher, Ronald Macatangay, Justus Notholt, C M. Roehl, Thorsten Warneke, Debra Wunch
Atmospheric Carbon Dioxide Retrieved From The Greenhouse Gases Observing Satellite (Gosat): Comparison With Ground-Based Tccon Observations And Geos-Chem Model Calculations, A Cogan, H Boesch, R Parker, L Feng, Paul Palmer, J-F Blavier, Nicholas M. Deutscher, Ronald Macatangay, Justus Notholt, C M. Roehl, Thorsten Warneke, Debra Wunch
Faculty of Science - Papers (Archive)
We retrieved column-averaged dry air mole fractions of atmospheric carbon dioxide (XCO 2) from backscattered short-wave infrared (SWIR) sunlight measured by the Japanese Greenhouse gases Observing SATellite (GOSAT). Over two years of XCO 2 retrieved from GOSAT is compared with XCO 2 inferred from collocated SWIR measurements by seven ground-based Total Carbon Column Observing Network (TCCON) stations. The average difference between GOSAT and TCCON XCO 2 for individual TCCON sites ranges from -0.87 ppm to 0.77 ppm with a mean value of 0.1 ppm and standard deviation of 0.56 ppm. We find an average bias between all GOSAT and TCCON …
Comment On The Ionization Energy Of B2f4, Bun Chan, Adam J. Trevitt, Stephen J. Blanksby, Leo Radom
Comment On The Ionization Energy Of B2f4, Bun Chan, Adam J. Trevitt, Stephen J. Blanksby, Leo Radom
Faculty of Science - Papers (Archive)
The Gn test sets(1) of accurate (uncertainty ≤ 1 kcal mol–1 ≈ 4 kJ mol–1) experimental data are widely employed in the development and assessment of quantum chemistry procedures. However, while all the data in the Gn sets nominally carry a sub-kcal mol–1 uncertainty, several of the experimental values show uncharacteristically large discrepancies when compared with values determined by high-level theoretical calculations. One of these questionable values is the adiabatic ionization energy (IE) of B2F4, for which the theoretical values calculated, for example, with the high-level G2 (1133.9, kJ mol–1),(1b) G3 (1135.4 kJ mol–1),(2) and G4 (1127.2 kJ mol–1)(3) procedures …
Evidence Of Enso Mega-Drought Triggered Collapse Of Prehistory Aboriginal Society In Northwest Australia, Hamish Mcgowan, Samuel K. Marx, P Moss, Andrew Hammond
Evidence Of Enso Mega-Drought Triggered Collapse Of Prehistory Aboriginal Society In Northwest Australia, Hamish Mcgowan, Samuel K. Marx, P Moss, Andrew Hammond
Faculty of Science - Papers (Archive)
The Kimberley region of northwest Australia contains one of the World's largest collections of rock art characterised by two distinct art forms; the fine featured anthropomorphic figures of the Gwion Gwion or Bradshaw paintings, and broad stroke Wandjina figures. Luminescence dating of mud wasp nests overlying Gwion Gwion paintings has confirmed an age of at least 17,000 yrs B.P. with the most recent dates for these paintings from around the mid-Holocene (5000 to 7000 yrs B.P.). Radiocarbon dating indicates that the Wandjina rock art then emerged around 3800 to 4000 yrs B.P. following a hiatus of at least 1200 yrs. …
Atmospheric Tomography: A Bayesian Inversion Technique For Determining The Rate And Location Of Fugitive Emissions, Ruhi Humphries, Charles Jenkins, Ray Leuning, Steve Zegelin, David Griffith, Christopher Caldow, Henry Berko, Andrew Feitz
Atmospheric Tomography: A Bayesian Inversion Technique For Determining The Rate And Location Of Fugitive Emissions, Ruhi Humphries, Charles Jenkins, Ray Leuning, Steve Zegelin, David Griffith, Christopher Caldow, Henry Berko, Andrew Feitz
Faculty of Science - Papers (Archive)
A Bayesian inversion technique to determine the location and strength of trace gas emissions from a point source in open air is presented. It was tested using atmospheric measurements of N2O and CO2 released at known rates from a source located within an array of eight evenly spaced sampling points on a 20 m radius circle. The analysis requires knowledge of concentration enhancement downwind of the source and the normalized, three-dimensional distribution (shape) of concentration in the dispersion plume. The influence of varying background concentrations of ~1% for N2O and ~10% for CO2 was removed by subtracting upwind concentrations from …
Channel Adjustments In Response To The Operation Of Large Dams: The Upper Reach Of The Lower Yellow River, Yuanxu Ma, He Qing Huang, Gerald C. Nanson, Yongi Li, Wenyi Yao
Channel Adjustments In Response To The Operation Of Large Dams: The Upper Reach Of The Lower Yellow River, Yuanxu Ma, He Qing Huang, Gerald C. Nanson, Yongi Li, Wenyi Yao
Faculty of Science - Papers (Archive)
The Yellow River in China carries an extremely large sediment load. River channel-form and lateral shifting in a dynamic, partly meandering and partly braided reach of the lower Yellow River, have been significantly influenced by construction of Sanmenxia Dam in 1960, Liujiaxia Dam in 1968, Longyangxia Dam in 1985 and Xiaolangdi Dam in 1997. Using observations from Huayuankou Station, 128 km downstream of Xiaolangdi Dam, this study examines changes in the river before and after construction of the dams. The temporal changes in the mean annual flow discharge and mean annual suspended sediment concentration have been strongly influenced by operation …
Development Of A Spatial Data Infrastructure For Coastal Management In The Amirante Islands, Seychelles, Sarah M. Hamylton, Justin Prosper
Development Of A Spatial Data Infrastructure For Coastal Management In The Amirante Islands, Seychelles, Sarah M. Hamylton, Justin Prosper
Faculty of Science - Papers (Archive)
Spatial data infrastructures play a key role in coastal management decision making in the Seychelles. This paper describes four components of a web-based spatial data infrastructure that were developed to facilitate coastal management of the Amirante Islands in the Seychelles. The four components include: (i) the institutional arrangement for using spatial data effectively to address local management challenges, (ii) the production of island habitat maps from remotely sensed data, (iii) the tasks undertaken for promoting access to and use of this spatial data, and (iv) an example of how this data is used for a specific coastal management application in …