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An obituary for aircraft designer Jim Bede is presented.

Objective:To examine the short‐term health effects of air pollution on daily mortality in four Australian cities (Brisbane, Melbourne, Perth and Sydney), where more than 50% of Australians reside.

Objective:To examine the short‐term health effects of air pollution on daily mortality in four Australian cities (Brisbane, Melbourne, Perth and Sydney), where more than 50% of Australians reside. Methods:The study used a similar protocol to APHEA2 (Air Pollution and Health: A European Approach) study and derived single‐city and pooled estimates. Results:The results derived from the different approaches for the 1996‐99 period showed consistent results for different statistical models used. There were significant effects on total mortality, (RR=1.0284 per 1 unit increase in nephelometry [10‐4.m‐1], RR=1.0011 per 1ppb increase in NO2), and on respiratory mortality (RR=1.0022 per 1ppb increase in O3). No significant differences between cities were found, but the NO2and particle effects may refer to the same impacts. Meta‐analyses carried out for three cities yielded estimates for the increase in the daily total number of deaths of 0.2% (‐0.8% to 1.2%) for a 10 μg/m3increase in PM10concentration, and 0.9% (‐0.7% to 2.5%) for a 10 μg/m3increase in PM2.5concentration. Conclusions:Air pollutants in Australian cities have significant effects on mortality.

Grass pollen is an important risk factor for allergic rhinitis and asthma in Australia and is the most prevalent pollen component of the aerospora of Brisbane, accounting for 71.6% of the annual airborne pollen load. A 5-year (June 1994–May 1999) monitoring program shows the grass pollen season to occur during the summer and autumn months (December–April), however the timing of onset and intensity of the season vary from year to year. During the pollen season, Poaceae counts exceeding 30 grains m –3 were recorded on 244 days and coincided with maximum temperatures of 28.1 ± 2.0 °C. In this study, statistical associations between atmospheric grass pollen loads and several weather parameters, including maximum temperature, minimum temperature and precipitation, were investigated. Spearman’s correlation analysis demonstrated that daily grass pollen counts were positively associated ( P < 0.0001) with maximum and minimum temperature during each sampling year. Precipitation, although considered a less important daily factor ( P < 0.05), was observed to remove pollen grains from the atmosphere during significant periods of rainfall. This study provides the first insight into the influence of meteorological variables, in particular temperature, on atmospheric Poaceae pollen counts in Brisbane. An awareness of these associations is critical for the prevention and management of allergy and asthma for atopic individuals within this region.

The influence of meteorological parameters on airborne pollen of Australian native arboreal species was investigated in the sub-tropical city of Brisbane, Australia over the five-year period, June 1994–May 1999. Australian native arboreal pollen (ANAP), shed by taxa belonging to the families Cupressaceae, Casuarinaceae and Myrtaceae accounts for 18.4% of the total annual pollen count and is distributed in the atmosphere during the entire year with maximum loads restricted to the months May through November. Daily counts within the range 11–100 grains m−3occurred over short intervals each year and were recorded on 100 days during the five-year sampling period. Total seasonal ANAP concentrations varied each year, with highest annual values measured for the family Cupressaceae, for which greater seasonal frequencies were shown to be related to pre-seasonal precipitation (r2= 0.76, p= 0.05). Seasonal start dates were near consistent for the Cupressaceae and Casuarinaceae. Myrtaceae start dates were variable and established to be directly related to lower average pre-seasonal maximum temperature (r2= 0.78, p= 0.04). Associations between daily ANAP loads and weather parameters showed that densities of airborne Cupressaceae and Casuarinaceae pollen were negatively correlated with maximum temperature (p< 0.0001), minimum temperature (p< 0.0001) and precipitation (p< 0.05), whereas associations with daily Myrtaceae pollen counts were not statistically significant. This is the first study to be conducted in Australia that has assessed the relationships between weather parameters and the airborne distribution of pollen emitted by Australian native arboreal species. Pollen shed by Australian native Cupressaceae, Casuarinaceae and Myrtaceae species are considered to be important aeroallergens overseas, however their significance as a sensitising source in Australia remains unclear and requires further investigation.

Relationships between weather parameters andairborne pollen loads of PinusinBrisbane, Australia have been investigated overthe five-year period, June 1994–May 1999.Pinuspollen accounts for 4.5% of the annualairborne pollen load in Brisbane where thePinusseason is confined to the winter months,July–early September. During the samplingperiod loads of 11–>100 grains m3wererecorded on 24 days and 1–10 grains m3on204 days. The onset and peak dates wereconsistent across each season, whereas the enddates varied. The onset of the Pinuspollen season coincided with the coolestaverage monthly temperatures (< 22°C),lowest rainfall (< 7mm), and four weeks afterdaily minimum temperatures fell to 5–9°Cin late autumn. Correlations obtained betweendaily airborne Pinuspollen counts andtemperature/rainfall parameters show thatdensities of airborne Pinuspollen arenegatively correlated with maximum temperature(p < 0.0001), minimum temperature (p < 0.0001)and rainfall (p < 0.05) during the mainpollination period. The mean duration of eachpollen season was 52 days; longer seasons wereshown to be directly related to lower averageseasonal maximum temperatures (r2= 0.85,p = 0.025). These results signify that maximumand minimum temperatures are the majorparameters that influence the onset andduration of the Pinuspollen season inthe environs of Brisbane. Respiratory allergyis an important health issue in Brisbane,Australia, but it remains unknown whether ornot airborne Pinuspollen is acontributing factor.

The main objective of this paper was to establish the effect of anthropogenic heat flux on the formation of mixing depth specially in urban areas. In this study an energy balance mixing depth model was developed for the simulation of mixing depth incorporating the heat island effect. To demonstrate the effect of heat island, mixing depths were simulated under two conditions. Under the first condition, hourly gridded anthropogenic heat flux and variant surface characteristics were considered, while under the second condition anthropogenic heat flux term was ignored and constant surface characteristics were considered throughout the modelling domain. The release of anthropogenic heat flux in the urban environment was found to be responsible for the growth of the unstable layer in the lower atmosphere even during the night. This resulted in higher mixing depth values in urban areas compared to the surrounding countryside. The maximum differential surfaces sensible heat flux between urban and rural areas was estimated as 130 W/m2. From the simulation of mixing depth, it was revealed that the maximum increment in mixing depth in urban areas was 300 m due to the heat island effect. This increment in mixing depth in urban areas can provide an extra space for dilution and mixing of pollutants.

The authors investigated the effects of ambient air pollution on hospital admissions in Brisbane, Australia. The authors used the Air Pollution on Health: European Approach protocol to examine the effects of particles, ozone, sulfur dioxide, and nitrogen dioxide on daily hospital admissions for asthma and respiratory, cardiovascular, and digestive disorders (control diagnosis) that occurred during the period 1987-1994. Ozone was consistently associated with admissions for asthma and respiratory disease—with little evidence of a threshold. In two-pollutant models, the ozone effect was relatively unaffected by the control for high levels of other pollutants. Particulate pollution (measured by nephelometry) was associated positively with admissions for respiratory disease and admissions for asthma in summer, whereas a negative association was observed for cardiovascular admissions. Although sulfur dioxide was associated significantly with admissions for respiratory and cardiovascular disease, a significant association was also found for the control diagnosis of digestive disorders. No significant associations were found for nitrogen dioxide over the study period, although significantly positive seasonal interactions were found for asthma and respiratory disease in autumn, winter, and spring. It was concluded that current levels of ambient air pollution in Brisbane make a significant contribution to the variation in daily hospital admissions for asthma and respiratory disease.

A one‐dimensional model is developed for the estimation of hourly mixing height values from routinely measured upper air and surface meteorological data. A diagnostic technique is used in the model to calculate the convective and mechanically induced mixing height values under different atmospheric, and day and night‐time conditions. In the scheme, for the day‐time hours, the mixing height is determined as the larger of the convective and mechanically induced mixing height values. For the night‐time hours, only the mechanically induced mixing height values are considered. Three‐hourly mixing height values are modelled using once‐a‐day upper air temperature profile data (from radio‐sonde) and three‐hourly surface meteorological data. The spatial and temporal variation of mixing height are modelled in the Brisbane airshed and their relationship with the atmospheric stability, solar radiation and transport wind speed is developed.

Environmental monitoring of airspora components at two sites in the Brisbane area was carried out for an 18 month period, to cover two peak periods for asthma incidence in this region. Fungal spores, especially those assigned to the Fungi Imperfecti, comprised the most numerous group, and pollen numbers in all samples were consistently low with grass the most abundant pollen. Cladosporium was the most abundant single taxon found throughout the year.Daily spore and pollen counts showed great variability over time. Spore and pollen levels at the two sites tended to show similar temporal patterns, although the magnitudes varied, possibly reflecting differences in microclimate and vegetation. Most fungal spora were present throughout the entire period with total spore counts peaking in late summer/autumn. Pollen groupings showed distinct peaks with Poaceae and Compositae abundant in autumn, Myrtaceae, Cupressaceae and Plantago peaking in spring and Pinus present only in winter. Overall numbers of spores were comparable with those reported in other more southern Australian areas, although grass pollen numbers were generally lower. Associations between airspora levels and different meteorological parameters are complex, but indicate strong relationships between wet air spora and humidity and rainfall, and significant relationships between temperature and humidity on both Alternaria and Cladosporium.

The results of several studies have indicated significant associations between daily mortality and air pollution, with little evidence of a threshold. In the current study, the authors examined daily mortality during the period 1987–1993 for the Brisbane region, which is the fastest-growing urban region in Australia (annual average concentration of particulate matter less than 10 μm in diameter = 27 μg/m3, maximum hourly sulfur dioxide level = 60 ppb, and maximum daily ozone hourly level = 118 ppb). The authors conducted a general estimating equation analysis, and they used autoregressive Poisson models for daily mortality to examine associations with air pollution variables. The authors used research methods developed in the Air Pollution on Health, European Approach (APHEA), project to control confounding effects of weather and temporal trends. The air pollutants examined included particulate pollution (measured by nephelometry [bsp data]), sulfur dioxide, ozone, and nitrogen dioxide. The results indicated that the associations between total daily mortality and particulate levels found in studies in the United States and other countries may be applicable in Brisbane, Australia. Ozone levels were also associated significantly with total daily mortality. There was little evidence of interaction between the ozone effects (mainly in summer) and particulates or with sulfur dioxide and nitrogen dioxide. The associations between pollutants (ozone, bsp) and daily mortality were significant only for individuals who were older than 65 y of age; positive associations were also found with cardiovascular disease categories, and the regression coefficients–when significant–were higher than those for total mortality. The results indicated a possible threshold for ozone levels, but a similar result for particulate levels was not apparent.

The main objective of this research is to identify the possible pollutant transport trajectories from the source to the receptor and to identify the location of areas of high pollution potential for ozone. In order to identify the regions which would most probably be affected by ozone and its precursors, a mesoscale trajectory model is developed and forward air‐parcel trajectories originating from Brisbane city are estimated. Eight trajectories per day, starting at 00, 03, 06, 09, 12, 15, 18 and 21 hours, are calculated for one complete calendar year. The probability distribution of trajectories shows seasonal and diurnal characteristics and prevailing transport routes of air pollution. Computer‐driven trajectories indicate that air parcels are concentrated in a region between mountainous ranges in the West and islands in the East. This study identifies potential pollutant transport paths and zones of high concentrations that would assist planners in selecting appropriate areas for future industrial and urban development.

Focuses on the development of the Ecological Footprint (EF) needed to assess the production of natural resources. Definition of EF; Effect of unsustainable consumption pattern on the deterioration of the global environment; Incorporation of consumption and human resources demands into an aggregate indicator of sustainability.