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William Dampier, one of England’s greatest navigators, named, described, and drew a profile of Long Island, Papua New Guinea in 1700. As this island produced a very large volcanic eruption with a disputed seventeenth- or eighteenth-century date, his observations assist in determining whether the eruption occurred before or after his visit. This contribution uses Dampier’s recorded observations to elucidate where the Roebuck was when the Long Island profile was drawn so that an appropriate comparison can be made with a modern profile of the island. This comparison confirms that the most recent major eruption of Long Island occurred before Dampier’s observations were made.

Correspondence from a long-established sugar mill provided the opportunity to construct the longest flood series for a river in Fiji—the Ba River in northwest Viti Levu—from 1892 to 2002. Flood waters reached the mill floor every four years on average. Contrary to common lore, this study could detect no increase in the frequency of major floods over the course of the 20th century, despite intensification of land use and siltation of the river channel over that time. Large, slow-moving tropical cyclones situated northwest of the valley have generated large floods, but so too have tropical rainstorms. Major floods have occurred in months when the Southern Oscillation Index (SOI) was both negative and positive, suggesting that the SOI is a poor indicator of flood potential for the Ba River.

The most important natural perils in Australia are tropical cyclones, earthquakes, bushfires, thunderstorms, floods, landslides and tsunamis. However, as far as residential buildings are concerned, the correct relative order of importance depends on the frames of reference used. Certainly, meteorological perils are more significant than geological hazards. Residential building damage produced by the most important natural hazards is assessed. Governance is shown to be poorly related to actual risk. Tropical cyclone wind-loading codes are amongst the best in the world, but the more limited potential for storm surge damage is largely ignored. While land-use regulations are strong in some states, almost no attention has been paid to appropriate building materials for flood-prone properties. Hail is probably the most important peril along the populated south-eastern seaboard, but no regulations govern roofing materials. Other issues relating to the present understanding of damage to buildings are raised.

Flooding in the business district of Kempsey, New South Wales, Australia, in 2001 allowed the collection and analysis of commercial flood damage data. Analysis indicated that direct losses were significant, totalling A$2.5 million. Data were variable owing to differences in the vulnerability of businesses to flood damage, differences in the impacts of the hazard upon businesses and survey uncertainty. Little direct relationship was found between direct commercial damage and over-floor water depth. Simple averaging and stage-damage curve loss estimation methods ignore the large variability present and result in inaccurate estimation of direct commercial damage. Probability loss estimation methods account for the variability present by assessing the chance of loss values occurring at specified depths of over-floor flooding.

Understanding the spatial structure of fine spatial resolution images is instrumental for either pixel- or object-based image analysis. In this Letter, the characteristic scale of scene variation in images is evaluated using statistics of sub-images produced by a wavelet transform. Six statistics, namely mean, variance, standard deviation (SD), coefficient of variation, skewness and kurtosis, were calculated for three directional sub-images and their derivative energy signature image at a sequence of wavelet decomposition levels. A simulated image, an aerial AUSIMAGE image (spatial resolution 0.2 ml and a recent Systeme Probatoire de l'Observation de la Terre (SPOT)-5 High Resolution Geometric (HRG) panchromatic image (spatial resolution 2.5 m) were analysed. It was found that with energy signature images, the change rate of SD over spatial resolution ranges between two successive decomposition levels (ASD/AR) suggested a synoptic and approximate description for the characteristic scale of scene variation. However, by comparing the result with the ranges of geostatistical variograms, it is suggested that the geostatistical method can correctly identify the characteristic scales of scene variation: semivariances can be calculated at any lag and orientation, while standard wavelet transforms are decomposed at only limited spatial resolution and orientation levels.

Earthquakes, tropical cyclones and floods are the most important natural perils in terms of human deaths on a global basis. In Australia, at least 4300 deaths in the last 200 years have been produced by heatwaves; about 2000–2200 each by tropical cyclones and floods; and bushfires and lightning strikes have each killed at least 650 people. On a global basis it appears that floods, tropical storms, droughts and earthquakes are the most damaging natural perils. In Australia, in terms of median damage per event, hailstorms are the most expensive insured natural peril, while three events—the 1989 Newcastle earthquake, 1974's Cyclone Tracy, and the 1990 Sydney hailstorm—produced 36 per cent of the total insured damage in the period since 1967. The Newcastle earthquake and the Sydney hailstorm have provided opportunities for new understandings of these perils and their consequences. While much has been learnt from the devastation of Rabaul town by the 1994 eruption, a rare opportunity for a detailed st...

(1974). Landslide form and hillslope morphology: An example from New Zealand. Australian Geographer: Vol. 12, No. 5, pp. 425-438.