‘Torrents of Terror’: the August 1998 Storm and the Magnitude,Frequency and Impact of Major Floods in the Illawarra Region of New South Wales

The Illawarra Region some 80 kilometres south of Sydney is characterised by a prominent coastal escarpment that rises to 700 m within 12 km of the coast and forms a locus for frequent, high intensity rainfall events. One of the most recent recorded events occurred on 17 August 1998 with rainfall intensities at several pluviometers exceeding 120 mm hr^‐1 over a duration of one hour, with up to 249 mm falling in 3.5 hours during the main storm burst. Detailed pluviometer data indicate that the storm was non‐stationary and moved down catchment producing a widespread zone of 120 mm hr^‐1 intensity rainfall over a 30 minute duration across mid‐lower catchment areas after similar intensity but longer duration rainfall in catchment headwaters. Slope‐area reconstructions of peak discharge indicate that small catchments on the escarpment within the zone of maximum intensity experienced close to 100% rainfall‐runoff relationships, with peak discharges correlated to short duration (<1 hr) peak rainfall intensities. Widespread erosion occurred particularly where urban development had encroached on natural water courses. Debris/hyperconcentrated flows originating from both anthropogenic and natural sediment sources caused damage to urban areas. This paper provides an overview of the spatial and temporal characteristics of the 17 August 1998 storm, the hydrologic and geomorphic response of the streams, and the nature of damage to urban areas. It reassesses the frequency of recent high‐magnitude rainfall/flood events in the region, discussing the relationships between rainfall intensities, estimates of flood magnitudes and stormwater channel capacities.     

Cognitive Maps and Spatial Behavior Of Consumers

Two multidimensional scaling algorithms are used to externally measure cognitive maps of supermarket locations for a sample of sixty-one supermarket shoppers. Issues raised in the construction of the cognitive maps are discussed. The relationship between the derived cognitive maps and consumer behavior is compared to the relationship between physical maps and consumer behavior. Behavior is shown to be more closely related to cognitive maps. Differences in cognitive maps are defined and canonically correlated with consumers' socioeconomic and locational attributes. While aggregate cognitive maps are closely associated with physical maps, there is substantial variation between individual maps. This variation is related to shopping behavior and selected socioeconomic and locational characteristics of consumers.     

RESIDENCE PATHS AND COMMUNITY PERCEPTION: A CASE STUDY FROM THE TORONTO URBAN FIELD

A typology of residence paths to Toronto urban field locations is developed to explore the importance of urban emigrants to the resettlement of the city's countryside and path relationships with local community perceptions. Residence paths are described by childhood and prior community types, current urban field residence location, and length of residence. Paths are dominated by large city residential experiences, but rural residential backgrounds are evident. Community perceptions, emphasizing satisfaction, are positive. Multiple classification analysis, in three model forms, identifies path-based variations in community satisfaction, and the strength of paths as predictors of satisfaction. Interpretations include links to ideas on the urban field advanced by Russwurm. L'auteur essaie de développer une typologie des sentiers de résidence dans le champ urbain de Toronto pour evaluer l'importance des émigrants urbains dans la colonisation de la périphérie rurale des villes. De plus, i l analyse les attitudes de la communauté locale en rapport avec ces sentiers. Ceux-ci sont tracés d'après les souvenirs d'enfance, les indications de cornmunautés antérieures, I'emplacement actuel de residences urbaines et la durke de residence. Les sentiers sont caracterisés par les expériences résidentielles propres à la grande ville mais on dégage également des arrière-fonds résidences rurales. Les attitudes de la communauté, qui révèlent une certaine satisfaction, s'averent positives. Une analyse à classement multiple, sous forme de trois modèles presente les variations de la satisfaction de la communauté fondées sur les sentiers et le poids des sentiers comme prédicteurs de satisfaction éventuelle. Parmi les interprétations, on trouve des liens avec les idées de Russwurm sur les champs urbains.