Analysis of an elongated narrow coronal streamer observed at the 1973 solar eclipse

A detailed photometric analysis has been made of a narrow elongated coronal streamer observed at the 1973 total eclipse. After deriving real intensity distributions, the electron density has been deduced under the assumption that the distribution is axially symmetric and that the decrease in density from the central axis follows the gaussian law. The results show that the gradient of the electron density is much steeper at the lower part, nearest to the solar limb, than those reported previously for larger scale streamers.On leave from the Observatorio de Huancayo, Instituto Geoflsico del Peru as a trainee of the Japan International Cooperation Agency.     

A ~ 40-year paleoenvironmental record from the Swan Oxbow,Yangtze River,China, inferred from testate amoebae and sedimentary pigments

Journal of Paleolimnology - We present a?~?40–year record of environmental change in the Swan Oxbow, Yangtze River, China, inferred from testate amoeba and sedimentary pigment...     

Effects of urbanization on stream hydrology and water quality: the Florida Gulf Coast

At the global scale, the population density of coastal areas is nearly three times that of inland areas, and consequently, land development represents a threat to coastal ecosystems. It is critical to understand how increasing urbanization affects coastal watersheds. To that end, the objective of this study was to examine the influence of urban development on stream water quality and hydrology in a coastal setting, a scenario that has received less attention than other physiographic regions. Stream hydrologic, physicochemical, and microbial data were collected in watersheds near Apalachicola, Florida with a range of impervious surfaces from 0 to 15%. Watersheds with greater impervious cover exhibited higher pH, specific conductance, and temperature, elevated nutrient concentrations and loads (, and total phosphorus), higher bacterial concentrations (fecal coliform and Escherichia coli), and increased maximum flow and hydrograph flashiness. Different responses to development here compared to other physiographic regions included lower total suspended solid concentrations, higher total dissolved solid concentrations, and a lack of response of base flow to increased urbanization. Additionally, Na⁺ and Cl^? concentrations were elevated to a greater extent than is often the case in non‐coastal areas. In the coming years, urban development is projected to increase substantially in coastal zones and thus there is risk of further stream degradation in coastal watersheds. Copyright © 2011 John Wiley & Sons, Ltd.     

Transportation mode-based segmentation and classification of movement trajectories

The knowledge of the transportation mode used by humans (e.g. bicycle, on foot, car and train) is critical for travel behaviour research, transport planning and traffic management. Nowadays, new technologies such as the Global Positioning System have replaced traditional survey methods (paper diaries, telephone) because they are more accurate and problems such as under reporting are avoided. However, although the movement data collected (timestamped positions in digital form) have generally high accuracy, they do not contain the transportation mode. We present in this article a new method for segmenting movement data into single-mode segments and for classifying them according to the transportation mode used. Our fully automatic method differs from previous attempts for five reasons: (1) it relies on fuzzy concepts found in expert systems, that is membership functions and certainty factors; (2) it uses OpenStreetMap data to help the segmentation and classification process; (3) we can distinguish between 10 transportation modes (including between tram, bus and car) and propose a hierarchy; (4) it handles data with signal shortages and noise, and other real-life situations; (5) in our implementation, there is a separation between the reasoning and the knowledge, so that users can easily modify the parameters used and add new transportation modes. We have implemented the method and tested it with a 17-million point data set collected in the Netherlands and elsewhere in Europe. The accuracy of the classification with the developed prototype, determined with the comparison of the classified results with the reference data derived from manual classification, is 91.6%.     

A numerical modelling study of coastal flooding

Summary A coastal ocean model capable of modelling tides, storm surge and the overland flow of floodwaters has been further developed to include the flux of water from tributaries and the forcing from wave breaking that leads to wave setup in the nearshore zone. The model is set up over the Gold Coast Broadwater on the east coast of Australia. This complex region features a coastal lagoon into which five tributaries flow and is subject to flooding from extreme oceanic conditions such as storm surge and wave setup as well as terrestrial runoff. Weather conditions responsible for storm surge, waves and flooding include cyclones of both tropical and mid-latitude origin. Two events are modelled. The first is an east coast low event that occurred in April 1989. This event verified well against available observations and analysis of the model simulations revealed that wave setup produced a greater contribution to the elevated water levels than the storm surge. The second case to be modelled was tropical cyclone Wanda, responsible for the 1974 floods. Modelled water levels in the Broadwater were reasonably well captured. Sensitivity experiments showed that storm surge and wave setup were only minor contributors to the elevated sea levels and their contribution was confined to the earlier stage of the event before the runoff reached its peak. The contribution due solely to runoff exhibited a tidal-like oscillation that was 180° out-of-phase with the tide and this was attributed to the greater hydraulic resistance that occurs at high tide. A simulation of this event with present day bathymetry at the Seaway produced sea levels that were 0.3–0.4 m lower than the simulation with 1974 bathymetry highlighting the effectiveness of deepened Seaway channel to reduce the impact of severe runoff events in the Broadwater. Received October 16, 2001 Revised December 28, 2001     

Environmental Rationalism and Beyond: Toward a more just sharing of power and influence

Economics, especially the narrowly defined form of economics known as neo-liberal economics, along with its policy derivative known as economic rationalism, dominates public and political debate and decision-making in Australia and many other nations as the twentieth century approaches its close. In the context of environmental issues, as also in that of welfare issues, the present over-dominance is unhealthy. Despite the best attempts of environmental economists and ecological economists, they have had relatively little influence on the broader economic profession, or on the political and business communities. Economics and free trade also dominate the international scene at the expense of equity and environmental issues. Environmental debates, by their very nature, are usually complex, requiring interdisciplinary and multidisciplinary approaches which include the economic perspective, but much else besides. Despite the importance of local context and spatial and temporal location, there is a need for a meta-theory or national philosophy to allow the integration across space and time so often needed. The present meta-theory, firmly based in economic rationalism, is inadequate as a basis for environmental decision-making. We desperately need a new meta-theory that explicitly integrates economic, environmental, welfare and many other perspectives. Perhaps such a meta-theory could be broadly based on the concept of sustainability, though much more work is needed to refine such an approach. A major swing in public opinion from the old meta-theory to the new is essential as a forerunner to political action, and education at all levels is needed to bring about this change. There are some signs that this change is already informing public opinion, and that it may have begun to influence mainstream Australian politics.     

Las Matras Block, Central Argentina (37°S-67°W): the Southernmost Cuyania Terrane and its Relationship with the Famatinian Orogeny

The Las Matras Block in Central Argentina constitutes the southernmost part of the Cuyania terrane, which was accreted to the southwestern margin of Gondwana during the Early to Mid Ordovician Famatinian orogeny. The Grenville-aged rocks of the Las Matras Block are represented by the tonalitic to trondhjemitic Las Matras pluton. A new U-Pb conventional zircon age of 1244±42 Ma confirms previous Sm-Nd and Rb-Sr isochron ages of this pluton. Mineral composition data are consistent with the tonalitic-trondhjemitic character of the pluton, and constrain its emplacement level to 1.9 to 2.6 kb. This shallow level of emplacement and the undeformed character of the pluton are distinctive features of this southernmost basement. A regional comparison indicates that the igneous-metamorphic evolution of the Grenville-aged basement rocks of the Cuyania terrane occurred over a period of more than 200 million years, with ages older than 1200 Ma up to those close to 1000 Ma. The shallowest crustal level is found in Las Matras, suggesting a southward shallowing of the exposed level of basement. The deformation and metamorphism associated with the collisional Famatinian orogeny affect both the Cuyania terrane and the adjacent western margin of Gondwana, and the Gondwana margin was also the locus of the related arc magmatism, but the compressive effects of the collision decrease in intensity toward the south. The Famatinian metamorphism and magmatism continue even further south into the Patagonia region, but the southern continuity of the Cuyania terrane into this region remains uncertain.     

The Southern Oscillation,environmental anomalies,and mortality of two Southern African seabirds

Mass mortalities and breeding failures of seabirds in the Pacific Ocean have been directly or indirectly linked to local manifestations of the Southern Oscillation. Similar seabird mortalities have been reported in the Benguela upwelling system along the southern African coast. A Boolean factor analysis of binary data (occurrence vs. non-occurrence) showed that certain worldwide and southern African anomalous climatic events tended to co-occur in the same year, and that seabird mortalities and scarcities of small fish along the southern African coast occurred in either the same year, or the year before, the anomalous climatic events. The environmental conditions leading up to warm-water events in southern Africa appear as detrimental to seabird populations as the warm-water events themselves.