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This paper presents the mathematical background of the derivation of atmospheric gravity-wave spectra from Rayleigh lidar observations of fractional density and/or temperature fluctuations.
Sporadic E, abbreviated Es, is a very thin ionised layer and as its name suggests, it occurs sporadically at E region heights. To a radio wave Es often behaves as a smooth HF reflector. However, because of its complex structure and large spatial and temporal variability Es is a major problem…
This article aims to give a comprehensive view of the distribution patterns for natural and artificial radionuclides over Antarctica. We focus this study on 137Cs, 210Pb and tritium. Applying various statistical methods, we show that the deposition of radionuclides reveals a structured distribution…
HF signals that propagate via the ionosphere may exhibit Doppler shifts due to a number of processes that give rise to a time dependent refractive index. This paper examines the role of ULF (1–100mHz) wave energy, incident from the magnetosphere, in causing Doppler shifts in HF signals.
Apparent drift motion of polar cap arcs may be indicative of plasma convection processes in the ionospheric plasma. The dynamics of a number of individual polar cap events observed by a dual wavelength all-sky imager at Scott Base have been analysed in detail. The imager…
A number of static GPS measurement campaigns have been made on a floating Antarctic ice shelf, the Amery Ice Shelf, as part of ongoing glaciological studies designed to investigate the ice shelf dynamics, grounding zone definition and ice shelf strain.
In the spring of 1995 an extensive global positioning system (GPS) survey was carried out on the Amery Ice Shelf, East Antarctica, providing ground-truth ellipsoidal height measurements for the European remote-sensing satellite (ERS) radar altimeters.
The 500 km wide swath of the right-looking ERS Wind scatterometer and the orbital geometry allows measurement of the microwave backscatter of all the Antarctic region between latitudes 55°S and 80°S each three days.
16S rDNA clone library analysis was used to identify bacterial biodiversity in a variety of sea-ice microbial communities (SIMCO). DNA was extracted from seven Antarctic sea-ice samples and … one Arctic sea-ice sample and 16S rDNA PCR-amplified using universal and Archaea-specific primers.
The 500 km wide swath of the ERS Wind scatterometer and its orbit geometry allows the measurement of the microwave backscatter of all the Antarctic region between latitudes 55°S and 79°S every three days.
The ice-free habitats of continental Antarctica are among the most geographically isolated on Earth. Colonization of Antarctica requires the immigration of dissemules from distant biotic sites across large distances of snow or open ocean.
We perform a theoretical analysis of Antarctic sea ice thickness estimates made using a ship-borne electromagnetic instrument.
It is commonly presumed that historic material in Antarctica should be well preserved because of the severe, dry cold. Examination of several historic Antarctic sites, however, reveals that many buildings and artefacts suffer deterioration from humidity.
ODP hole 504B in the eastern Pacific intersected a thick zone of 1-5% sulfide sulfur at the contact between basalts and underlying sheeted dikes.
The extent of genetic variation and dispersal mechanisms were investigated over short distances of 1 – 100 m and up to 3 km, by the RAPD technique, for the moss Sarconeurum glaciale at three locations on Ross Island, Antarctica. At Arrival Heights, genetic variation occurred within single colonies…
Measurements of crystal size have been made on seven firn cores drilled at sites covering a range of mean annual temperature from -12.6 °C to -52.5 °C and a range of accumulation rate from 52 to 315 kg/sq.m/a. The sorting coefficient…
The temperature of upper 20 m was measured at four sites, S1, LJ, LJ24 and BJ, during a period of 21 months at the western Law Dome, Antarctica. the sensors were emplaced at the depths of 1, 2.5, 5, 7.5, 10, 15 and 20 m. S1 is in ablation sphere with a dynamo-metamorphosed ice…
A comprehensive, airborne survey of the Vanderford and Adams glaciers was started in January 1983, continued through the austral summer season 1984/5, and completed in February 1985. Ice thickness and surface-elevation data were collected over some 4500 square kilometres…
Ice velocity, surface elevation, and ice thickness were measured along oversnow traverse routes in the sector of Wilkes Land, East Antarctica, bounded by long. 93°E and 131°E, and the coast and lat. 75°S.
Around the Antarctic continent, polynyas form within the sea ice due to wind-forcing or upwelling of warm ocean water. Acting as ventillators in the ice cover, polynyas accelerate the exchange of energy, gas and aerosol at the ocean/atmosphere boundary…
The ERS-1 wind scatterometer is an active microwave instrument operating at 5.3 GHz in the C-band with VV-polarisation. Measurements of the microwave backscatter coefficient of the surface are made at regularly spaced points within a 500 km wide swath along each orbit.
Break-up of ice shelves has been regarded as an indicator of climate change1. Observations around the Antarctic Peninsula have shown a pattern of gradual retreat, associated with a regional atmospheric warming and increased summer melt and fracturing processes2-9.
The presence of water, snow and ice in abandoned Antarctic buildings can cause serious problems for their preservation. This is due to mechanical damage from the waters changing state and mass, as well as biological damage from the growth of mould and the corrosion of metals in wet conditions.
A Lowell Digital Ionosonde (DPS-4) has operated at the Australian Antarctic polar cap station Casey (-80.6o CGM latitude), since early 1993, primarily to study the dynamics of the southern polar cap ionosphere. To gain a better understanding of the ionospheric motions involved…