Cooperative Research Centre

About: Cooperative Research Centre is a based out in . It is known for research contribution in the topics: Population & Sea ice. The organization has 7633 authors who have published 8607 publications receiving 429721 citations.

A Dynamic and Spatial Scaling Approach to Advection Forecasting

Abstract: Quantitative nowcasts of rainfall are frequently based on the advection of rain fields observed by weather radar. Spectral Prognosis (S-PROG) is an advection-based nowcasting system that uses the observations that rain fields commonly exhibit both spatial and dynamic scaling properties, that is, the lifetime of a feature in the field is dependent on the scale of the feature (large features evolve more slowly than small features), and that features at all scales between the outer and inner observed scales are present in the field. The logarithm of the radar reflectivity field is disaggregated into a set or cascade of fields, in which each field in the set (or level in the cascade) represents the features of the original field over a limited range of scales. The Lagrangian temporal evolution of each level in the cascade is modeled using a simple autoregressive (lag 2) model, which automatically causes the forecast field to become smooth as the structures at the various scales evolve through their life cycles, or can be used to generate conditional simulations if the noise term is included. This paper describes the model and presents preliminary results.

Observed decreases in oxygen content of the global ocean

Abstract: Comparing the high-quality oxygen climatology from the World Ocean Circulation Experiment to earlier data we reveal near-global decreases in oxygen levels in the upper ocean between the 1970s and the 1990s. This globally averaged oxygen decrease is −0.93 ± 0.23 mmol l−1, which is equivalent to annual oxygen losses of −0.55 ± 0.13 × 1014 mol yr−1 (100–1000 m). The strongest decreases in oxygen occur in the mid-latitudes of both hemispheres, near regions where there is strong water renewal and exchange between the ocean interior and surface waters. Approximately 15% of global oxygen decrease can be explained by a warmer mixed-layer reducing the capacity of water to store oxygen, while the remainder is consistent with an overall decrease in the exchange between surface waters and the ocean interior. Here we suggest that this reduction in water mass renewal rates on a global scale is a consequence of increased stratification caused by warmer surface waters. These observations support climate model simulations of oxygen change under global warming scenarios.

Stable isotope dilution analysis of wine fermentation products by HS-SPME-GC-MS.

Abstract: The aim of this study was to quantify, in a single analysis, 31 volatile fermentation-derived products that contribute to the aroma of red and white wine. We developed a multi-component method based on headspace solid-phase microextraction coupled with gas chromatography mass spectrometry (HS-SPME-GC-MS). The 31 volatile compounds analysed include ethyl esters, acetates, acids and alcohols. Although these compounds have a range of functional groups, chemical properties, volatilities, affinities for the SPME fibre, and are found in wine at various concentrations, the accuracy of the analysis was achieved with the use of polydeuterated internal standards for stable isotope dilution analyses (SIDA). Nine of the labelled standards were commercially available, while 22 were synthesised. The method was validated by a series of duplicate spiked standard additions to model, white and red wine matrices over the concentration range relevant for each compound in wine. This demonstrated that the appropriate use of SIDA helped to account for matrix effects, for instance potential sources of variation such as the relative response to the MS detector, ionic strength, ethanol content and pH of different wine matrices. The resultant calibration functions had correlation coefficients (R2) ranging from 0.995 to 1.000. Each compound could be quantified at levels below its aroma threshold in wine. Relative standard deviations were all <5%. The method was optimised for the best compromise (over the 31 compounds) of wine dilution factor, level of sodium chloride addition, SPME fibre, SPME temperature, SPME time, GC column and MS conditions. Confirmation of identity was achieved by retention time and peak shape, and measurement of at least three ions for each analyte and internal standard with the MS operating in selected ion monitoring mode to facilitate more precise quantitation with a high sampling rate. The method is a valuable research tool with many relevant applications. A novel method for the combined chiral separation and SIDA quantification of 2- and 3-methylbutanoic acid is also demonstrated.

Aspects of geochronology and crustal evolution in the Eastern Fold Belt, Mt Isa Inlier∗

Abstract: Zircon U‐Pb SHRIMP ages and crustal Sm‐Nd signatures are reported for metasediments, meta‐volcanics, and a variety of pre‐ and post‐tectonic granitoid intrusives in the Eastern Fold Belt of the Mt Isa Inlier. These enable tracing of the broad crustal evolution of the rocks, erection of a chrono‐stratigraphic framework in the Eastern Fold Belt, and correlation of these rocks with those in other parts of the Mt Isa Inlier and in other Proterozoic inliers of northern Australia. The SHRIMP results and Sm‐Nd model ages provide quantitative information related to the provenance history of the metasediments and the sources and crustal interactions of magmatic rocks. Most of the latter have Nd Tdm of 2270–2200 Ma, suggesting similar source(s) to the metasediments and gneisses (2360–2140 Ma). The Nd TDM model ages are younger than those found in the Kalkadoon‐Leichhardt Belt, suggesting that the Eastern Fold Belt crust received less Archaean source input. Rocks of Barramundi age (1870–1840 Ma) are not found in the...