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On the surface, the severity of the Antarctic environment is sufficient to account for the injury rates that might occur there. However, it is argued that injury occurrence is the outcome of multiple factors. A number of such factors…
The foraging behaviour of Adélie penguins Pygoscelis adeliae was studied simultaneously at Shirley Island (SI, 110° E) and at Petrel Island (PI, 140° E) in approximate conjunction with the ship-based krill survey conducted on board the RSV Aurora Australis.
An inductive-limit model has been used to determine … footprint sizes for a variety of common airborne … electromagnetic-survey geometries. The model accounts … both for variations in the height and orientation of … the electromagnetic transmitter…
Until recently, the IGS network of global tracking sites was predominently populated y Rogue/Turborogue GPS receivers. Firmware used in these receivers was found to perform poorly during periods of high ionospheric disturbances and, during 1999/2000…
Bubbles of air trapped in ice sheets provide an important record of past atmospheric gas composition. Understanding of climate change and atmospheric composition over the last 400,000 years has been greatly improved using ice core analysis.
Laboratory ice deformation experiments are described that use an apparatus designed to apply a simple shear stress configuration. Ice samples are deformed by the application of horizontal parallel forces, with no vertical forces imposed…
A Rayleigh lidar was operated at Kingston, Tasmania on 22 nights between March 1997 and April 1999. During this interval, profiles of scattering ratio obtained from the lidar data indicate that the stratospheric aerosol layer extended up to a maximum altitude of about 34km.
Middle-atmosphere gravity wave spectra of energy against vertical wavenumber are usually assumed to have a log-log slope of -3, based on a number of studies over many years and geographical locations, as well as from theoretical work.
Pc3-4 pulsations observed at high-latitudes have been examined for evidence of magnetic field line resonances. Previous studies have suggested that these pulsations are due to harmonics of the lower frequency Pc5 pulsations.
High-resolution Fabry-Perot spectrometer observations of the OH(62) Q1(1) line, l834.46 nm, were made at Mawson, 67.6ºS 62.9ºE, and Davis, 68.6ºS 78.0ºE, Antarctica, in 1997. The observing program resulted in three sets of continuous OH observations suitable for tidal analysis: July 25…
Variations in the atmospheric, near-surface vertical electric field component Ez measured at the Russian Antarctic station Vostok in 1998 are analyzed in conjunction with changes of the interplanetary magnetic field (IMF).
The so-called ionosonde drift technique of determining ionospheric velocities from angle-of-arrival and Doppler shift measurements is now well established. In the standard digital ionosonde technique, commonly called the drift mode…
Ionospheric Total Electron Content (TEC) determined from July 1991 to June 1995 is examined from southern Australia using Global Positioning System (GPS) satellite data recorded by the Defence Science and Technology Organisation at Salisbury, South Australia.
A UMLCAR ( University of Massachusetts Lowell, Centre for Atmospheric Research) Digital Ionosonde (DPS-4) has operated at the Australian Antarctic polar cap station Casey (80.8oS geomagnetic latitude) since early 1993, primarily to study the dynamics of the southern polar cap ionosphere.
We report the first systematic survey of cosmic ray precursors of geomagnetic storms. Our data set comprises the 14 “major” geomagnetic storms (peak Kp >= 8–) identified by Gosling et al. (1990) together with 25 large storms (peak Kp >= 7–) observed from 1992 through 1998.
The Weimer and IZMEM statistical convection models are driven with a time series of interplanetary magnetic field (IMF) measurements made onboard the Wind spacecraft. The model outputs are used to infer convection velocity at Casey, Antarctica (80.8°S geomagnetic latitude)…
Signatures of the ionospheric cusp in HF digital ionosonde measurements of plasma drift made at the polar cap station Casey, Antarctica (-80.8° geomagnetic latitude) are investigated. Measurements recorded during the campaign interval February 13-17…
Ground-based Fabry-Perot spectrometer observations from the Australian Antarctic stations of Davis and Mawson show an upward wind ~100 m s-1 in the thermosphere at ~240 km altitude on the night of Day of Year 159 in 1997.
A two-day workshop was held at the Australian Academy of Sciences to discuss how reconstructions of past climate change might be better applied to modelling future potential climate change. Recommendations included: (1)…
Traditionally many marine mammal populations are estimated by visual surveys of the number of ‘available’ animals (eg pack-ice seals hauled out on ice floes) with correction for the number not available (those in the water). However…
Ideally, evidence from long-duration spaceflight should be used to predict likely occurrences of behavioral health events and for planning management strategies for such events. With small numbers of space travelers, and limited … long-duration missions of a year or more…
Eight years ofaltimetry and hydrographic data are used to examine the formation, propagation and vertical … characteristics ofcold-core rings formed north ofthe Subantarctic Front, SAF, in the region south ofTasmania. Altimetry allows us to follow the spatial–temporal evolution of these cold…