Laboratory Experiments on Convective Entrainment Using a Saline Water Tank

Entrainment fluxes in a shear-free convective boundary layer have been measured with a saline water tank set-up. The experiments were targeted towards measuring the entrainment behaviour for medium to high Richardson numbers and use a two-layer design, i.e. two stacked non-stratified (neutral) layers with different densities. With laser induced fluorescence (LIF), the entrainment flux of a fluorescent dye is measured for bulk Richardson numbers in the range 30–260. It is proposed that a carefully chosen combination of top-down and bottom-up processes improves the accuracy of LIF-based entrainment observations. The observed entrainment fluxes are about an order of magnitude lower than reported for thermal water tanks: the derived buoyancy entrainment ratio, $A$ , is found to be $A \approx 0.02$ , which is to be compared with $A\approx 0.25$ for a thermal convection tank (Deardorff et al., J Fluid Mech 100:41–64, 1980). An extensive discussion is devoted to the influence of the Reynolds and Prandtl numbers in laboratory experiments on entrainment.     

Physically based evaluation of climate models over the Iberian Peninsula

A novel approach is proposed for evaluating regional climate models based on the comparison of empirical relationships among model outcome variables. The approach is actually a quantitative adaptation of the method for evaluating global climate models proposed by Betts (Bull Am Meteorol Soc 85:1673–1688, 2004). Three selected relationships among different magnitudes involved in water and energy land surface budgets are firstly established using daily re-analysis data. The selected relationships are obtained for an area encompassing two river basins in the southern Iberian Peninsula corresponding to 2 months, representative of dry and wet seasons. The same corresponding relations are also computed for each of the thirteen regional simulations of the ENSEMBLES project over the same area. The usage of a metric based on the Hellinger coefficient allows a quantitative estimation of how well models are performing in simulating the relations among surface magnitudes. Finally, a series of six rankings of the thirteen regional climate models participating in the ENSEMBLES project is obtained based on their ability to simulate such surface processes.     

The 2010/2011 Canterbury earthquakes: context and cause of injury

The aim of this study was to investigate causes of injury during the 2010/2011 Canterbury earthquakes. Data on patients injured during the Darfield (4 September 2010) and Christchurch (22 February 2011) earthquakes were sourced from the New Zealand Accident Compensation Corporation. The total injury burden was analyzed for demography, context of injury, causes of injury, and injury type. Injury context was classified as direct (shaking of the primary earthquake or aftershocks causing unavoidable injuries), action (movement of person during the primary earthquake or aftershocks causing potentially avoidable injuries), and secondary (cause of injury after shaking ceased). Nine categories of injury cause were identified. Three times as many people were injured in the Christchurch earthquake as in the Darfield earthquake (7,171 vs. 2,256). The primary shaking caused approximately two-thirds of the injuries from both quakes. Actions during the primary shaking and aftershocks led to many injuries (51.3 % Darfield and 19.4 % Christchurch). Primary direct caused the highest proportion of injuries during the daytime Christchurch quake (43.6 %). Many people were injured after shaking stopped in both events: 499 (22.1 % Darfield) and 1,881 (26.2 % Christchurch). Most of these people were injured during clean-up (320 (14.2 %) Darfield; 622 (8.7 %) Christchurch). In both earthquakes, more females than males (1,453 vs. 803 Darfield; 4,646 vs. 2,525 Christchurch) were injured (except by masonry, damaged ground, and during clean-up); trip/fall (27.9 % Darfield; 26.1 % Christchurch) was the most common cause of injury; and soft tissue injuries (74.1 % Darfield; 70.4 % Christchurch) was the most common type of injury. This study demonstrated that where people were and their actions during and after earthquakes influenced their risk of injury.     

Book reviews

THE CAPITALIST SPACE ECONOMY: Geographical Analysis after Ricardo, Marx and Sraffa by E. Sheppard and T. J. Barnes. 15 × 22 cm, xviii and 328 pages. Unwin Hyman: London 1990 (ISBN 004 330401 X) £40.00 hard; (ISBN 004 330402 8) £14.95 (soft).

THE INTERNATIONAL STEEL INDUSTRY: Restructuring, State Policies and Localities by R. Hudson and D. Sadler. 14 × 22 cm, xii and 163 pages. Routledge: London 1989 (ISBN 0 415 02186 3) $A89.95 (hard).

INDUSTRIAL TRANSFORMATION AND CHALLENGE IN AUSTRALIA AND CANADA (Carleton Library No. 164) edited by R. Hayter and P. D. White. 15 × 23 cm, x and 340 pages. Carleton University Press: Ottawa 1990 (ISBN 0 88629 129 1) $A34.95 (hard); (ISBN 0 88629 128 3) $A 19.95 (soft).

LABOUR MIGRATION. The Internal Geographical Mobility of Labour in the Developed World edited by J. H. Johnson and J. Salt. 15 × 24 cm, viii and 215 pages. David Fulton: London 1990 (ISBN 1 85346 120 2) £30.00 (hard).

CITIES IN SPACE: CITY AS PLACE by D. Herbert and C. Thomas. 15 × 23 cm, xi and 340 pages. David Fulton: London 1990 (ISBN 1 85346 138 5) £35.00 (hard); (ISBN 1 85346 109 1) £14.95 (soft).

THE NEW URBAN FRONTIER. Urbanisation and City Building in Australasia and the American West by L. Frost. 15 × 23 cm, xvii and 226 pages. New South Wales University Press: Sydney (ISBN 0 86840 268 0) $A24.95 (soft).

SYDNEY: A Social Atlas by R. Horvath, G. E. Harrison and R. M. Dowling. 19 × 28 cm, 110 pages. Sydney University Press: Sydney 1989 (ISBN 0 424 00144 6) $A19.95 (soft).

CHANGE AND ADJUSTMENT IN NORTHERN NEW SOUTH WALES edited by D. J. Walmsley. 17 × 23 cm. 118 pages. Department of Geography and Planning, University of New England: Armidale 1990 (ISBN 0 85834 887 X) $A10.00 (soft).

ANNOTATED BIBLIOGRAPHY OF URANIUM IN AUSTRALIA (Cover Title: URANIUM IN AUSTRALIA 1970–1987: An Annotated Bibliography) by C. O'Faircheallaigh, A. Webb and D. Wade‐Marshall. 18 × 25 cm, xi and 306 pages. North Australia Research Unit, Australian National University: Darwin 1989 (ISBN 07315 05433).     

A combined spectrophotometric and morphometric study of the lunar mare dome fields near Cauchy, Arago, Hortensius, and Milichius

In this study we examine the spectral and morphometric properties of the four important lunar mare dome fields near Cauchy, Arago, Hortensius, and Milichius. We utilize Clementine UV-vis multispectral data to examine the soil composition of the mare domes while employing telescopic CCD imagery to compute digital elevation maps in order to determine their morphometric properties, especially flank slope, height, and edifice volume. After reviewing previous attempts to determine topographic data for lunar domes, we propose an image-based 3D reconstruction approach which is based on a combination of photoclinometry and shape from shading. Accordingly, we devise a classification scheme for lunar mare domes which is based on a principal component analysis of the determined spectral and morphometric features. For the effusive mare domes of the examined fields we establish four classes, two of which are further divided into two subclasses, respectively, where each class represents distinct combinations of spectral and morphometric dome properties. As a general trend, shallow and steep domes formed out of low-TiO₂ basalts are observed in the Hortensius and Milichius dome fields, while the domes near Cauchy and Arago that consist of high-TiO₂ basalts are all very shallow. The intrusive domes of our data set cover a wide continuous range of spectral and morphometric quantities, generally characterized by larger diameters and shallower flank slopes than effusive domes. A comparison to effusive and intrusive mare domes in other lunar regions, highland domes, and lunar cones has shown that the examined four mare dome fields display such a richness in spectral properties and 3D dome shape that the established representation remains valid in a more global context. Furthermore, we estimate the physical parameters of dome formation for the examined domes based on a rheologic model. Each class of effusive domes defined in terms of spectral and morphometric properties is characterized by its specific range of values for lava viscosity, effusion rate, and duration of the effusion process. For our data set we report lava viscosities between about 10² and , effusion rates between 25 and , and durations of the effusion process between three weeks and 18 years. Lava viscosity decreases with increasing R₄₁₅/R₇₅₀ spectral ratio and thus TiO₂ content; however, the correlation is not strong, implying an important influence of further parameters like effusion temperature on lava viscosity.     

XTE J1550–564: a superluminal ejection during the September 1998 outburst

In 1998 September, the X-ray transient XTE J1550–564 underwent amajor outburst in soft and hard X-rays, followed by a radio flare. Australian Long Baseline Array imagesobtained shortly after the peak in the radio flare showed evolving structure.The components observed have an apparent separation velocity of >2c.     

Flood hazard and damage assessment in the Ebro Delta (NW Mediterranean) to relative sea level rise

The impact of relative sea-level rise (RSLR), damage to and possible responses in the Ebro Delta (NW Mediterranean) has been analyzed. Impact was determined by delineating delta areas prone to flooding under different RSLR scenarios. The surface areas of the different habitats were then quantified for flooding impact and affected ecosystems were assessed. The obtained results enabled us to characterize the Ebro Delta as a coastal environment that is highly sensitive to changes in sea level, with affected flooded areas likely to range between about 45 and 60 % for different RSLR scenarios, from which about 26 % would be inundated by subsidence only. In absolute terms, the habitat most likely to be affected by flooding was cropland. In relative terms, the most affected habitats were those typical of the lowest areas: saltwater wetlands, riparian buffer and areas of saline vegetation. Under present deltaic evolution with no sediment supply, adaptation is considered a plausible option for managing the Ebro delta under a RSLR scenario. This implies permitting surface area losses or land use changes in the lower parts of the delta, where natural values will be reinforced, and concentrating agriculture in the higher parts of the deltaic plain.