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Papers by Stuart Henderson

Australian Meteorological and Oceanographic Journal, Dec 1, 2014

Philosophical Transactions of the Royal Society A, May 15, 2001

Journal of Southern Hemisphere Earth Systems Science, 2021

While the Montreal Protocol is reducing stratospheric ozone loss, recent increases in some ozone ... more While the Montreal Protocol is reducing stratospheric ozone loss, recent increases in some ozone depleting substance (ODS) emissions have been identified that may impact southern hemisphere climate systems. In this study, we discuss characteristics of the 2018 and 2019 Antarctic ozone holes using surface in situ, satellite and reanalysis data to gain a better understanding of recent ozone variability. These ozone holes had strongly contrasting characteristics. In 2018, the Antarctic stratospheric vortex was relatively stable and cold in comparison to most years of the prior decade. This resulted in a large and persistent ozone hole that ranked in the upper-tercile of metrics quantifying Antarctic ozone depletion. In contrast, strong stratospheric warming in the spring of 2019 curtailed the development of the ozone hole, causing it to be anomalously small and of similar size to ozone holes in the 1980s. As known from previous studies, the ability of planetary waves to propagate into ...

Journal of Southern Hemisphere Earth Systems Science, 2019

We reviewed the 2015 and 2016 Antarctic ozone holes, making use of a variety of ground-based and ... more We reviewed the 2015 and 2016 Antarctic ozone holes, making use of a variety of ground-based and spacebased measurements of ozone and ultraviolet radiation, supplemented by meteorological reanalyses. The ozone hole of 2015 was one of the most severe on record with respect to maximum area and integrated deficit and was notably longlasting, with many values above previous extremes in October, November and December. In contrast, all assessed metrics for the 2016 ozone hole were at or below their median values for the 37 ozone holes since 1979 for which adequate satellite observations exist. The 2015 ozone hole was influenced both by very cold conditions and enhanced ozone depletion caused by stratospheric aerosol resulting from the April 2015 volcanic eruption of Calbuco (Chile).

International Journal of Environmental Research and Public Health, 2019

Seasonality in glucose metabolism has been observed in adult populations; however, little is know... more Seasonality in glucose metabolism has been observed in adult populations; however, little is known of the associations between season and glucose metabolism in children. In this study, we examined whether markers of glucose metabolism (fasting glucose, insulin and HbA1c) varied by season in a paediatric population (6–13 years of age) located in Perth (Western Australia, n = 262) with data categorised by weight. Linear regression was used to analyse the nature of the relationships between mean daily levels of terrestrial ultraviolet radiation (UVR) (prior to the day of the blood test) and measures of glucose metabolism. Fasting blood glucose was significantly lower in autumn compared to spring, for children in combined, normal and obese weight categories. Fasting insulin was significantly lower in autumn and summer compared to winter for individuals of normal weight. HbA1c was significantly higher in summer (compared with winter and spring) in overweight children, which was in the op...

Australian Meteorological and Oceanographic Journal, 2014

Australian Meteorological and Oceanographic Journal, 2011

Photochemistry and Photobiology, 2009

A study to assess the potential exposure to solar UV radiation of expeditioners on Australian Ant... more A study to assess the potential exposure to solar UV radiation of expeditioners on Australian Antarctic resupply voyages was carried out over the Austral summers of 2004/2005 to 2006/2007. Subjects wore UVR‐sensitive polysulphone (PS) badges on the chest for the duration of their working day, which generally ranged from 5 to 10 h, but could be as long as 14 h. Measurements were carried out during unloading of two vessels while they were at the three Australian Antarctic stations. The subjects wore standard Australian Antarctic Division clothing assemblages, although the face and hands and in some cases more of the limbs were uncovered and subjected to exposure to UVR. The badges worn by the subjects received exposures ranging from 0.2 to 18 standard erythemal doses (SEDs), with a median of 3.2 SEDs. However, comparison with occupational exposure limits showed that more than 80% of the subjects’ PS badges received UVR exposures in excess of the limits while 31% received more than fiv...

Photochemistry and Photobiology, 2007

In recent years, SunSmart campaigns have emphasized the importance of the use of shade as a strat... more In recent years, SunSmart campaigns have emphasized the importance of the use of shade as a strategy in the reduction of human exposure to solar UV radiation (UVR), particularly in early life with the provision of shade in schools. Trees can play an important role in shade provision, either as the main shade provider or to augment shade structures and increase UVR protection provided to the general population. A study to measure the protection provided by a range of trees common in Australian urban environments was undertaken during the summers of 2004/2005 and 2005/2006. Solar UVR beneath the trees was measured using UVR sensitive polysulphone badges positioned horizontally within the shaded area and were compared with those in full sunshine to give an indication of the protection provided. Measurements made on sunny days during the months of October to April indicated that the shade cover provided by the trees depended upon the tree species and changed with season as a result of c...

Philosophical Transactions of the Royal Society of London. Series A: Mathematical, Physical and Engineering Sciences, 2001

Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2001

Journal of Southern Hemisphere Earth Systems Science, 2022

The Antarctic ozone hole remains the focus of scientific attention because of its importance to t... more The Antarctic ozone hole remains the focus of scientific attention because of its importance to the health of the biosphere and its influence on the climate of the southern hemisphere. Here we examine the general characteristics of the 2020 Antarctic ozone hole using a variety of observational and reanalysis data and compare and contrast its behaviour with earlier years. The main feature of the 2020 ozone hole was its relatively large size, and persistence to the beginning of the 2020/2021 summer, with new maximum records being set for the ozone hole daily area and ozone mass deficit during November and December. This was in strong contrast to 2019 when the ozone hole was one of the smallest observed. We show that a key factor in 2020 was the relative stability and strength of the stratospheric polar vortex, which allowed low temperatures in the Antarctic lower stratosphere to enhance ozone depletion reactions in relative isolation from the rest of the global atmosphere. These condi...

Physical Review Letters, 2002

We describe direct measurements of the dynamics of two colloidal spheres before hydrodynamic inte... more We describe direct measurements of the dynamics of two colloidal spheres before hydrodynamic interactions have had time to fully develop. We find that the dynamics of the two spheres are coupled at times significantly shorter than t n , the time required for vorticity to diffuse between the two spheres. From the distance dependence of the measured coupling, we infer that hydrodynamic interactions develop in a sonic time scale.

Journal of Physics: Condensed Matter, 2002

We have used a high-resolution back-focal-plane detector to make simultaneous measurements of the... more We have used a high-resolution back-focal-plane detector to make simultaneous measurements of the axial and lateral force constants of a micron-sized particle in a single-beam optical gradient trap. We measure the optical force applied to the trapped particle as a function of the relative index of refraction of particle and medium, the radius of the particle, and the laser beam power. Results are compared with recent theoretical predictions.

Photochemistry and Photobiology, 2013

During August 2011 stratospheric ozone over much of Southern Australia dropped to very low levels... more During August 2011 stratospheric ozone over much of Southern Australia dropped to very low levels (approximately 265 Dobson Units) for over a week above major population centers. The weather during this low ozone period was mostly clear and sunny, resulting in measured solar ultraviolet radiation (UVR) levels up to 40% higher than normal, with UV Index > 3 despite being winter. Satellite ozone measurements and meteorological assimilated data indicate that the event was likely due in large part to the anomalous southward movement over Australia of ozone‐poor air in the lower stratosphere originating from tropical latitudes. At the time, a study measuring the UVR exposures of outdoor workers in Victoria was underway and a number of the workers recorded substantial UVR exposures and were sunburnt. Given the cities and populations involved (approximately 10 million people), it is likely that many people could have been exposed to anomalously high levels of solar UVR for that time of ...