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Thesis (M.L.Arch.)--University of Adelaide, Dept. of Architecture, 2002. / "February 2002" Bibliography: leaves 117-128.

Thesis (M.S. in Meteorology and Physical Oceanography) Naval Postgraduate School, September 1994. / Thesis advisor(s): Robert H. Bourke, and James H. Wilson. "September, 1994." "NPS-OC-94-05." Includes bibliographical references (p. 171-172). Also available online.

Examining fish behaviour through acoustic tracking is a technique being employed more and more. Typically, research using this method focuses on detections without fully considering the influence of both the physical and acoustic environment. Here we link the aquatic environment of Cumberland Sound with factors influencing the detection effectiveness of fish tracking equipment and found multi-path signal interference to be a major issue while seasonal variabilty had little impact. Cumberland Sound is a remote Arctic embayment, where three species of deep-water fish are currently tracked, that can be considered as two separate layers. Above the 300 m deep sill, the cold Baffin Island Current follows a geostrophic pattern, bending into the sound along the north shore, circulating before leaving along the south shore. The warm deep water is replenished from the recirculated arm of the West Greenland Current occasionally flowing over the sill and down to a stable depth. This influx of water prevents deep water hypoxia, allowing the deep-dwelling fish populations in the sound to thrive. To complement the work done in Cumberland Sound, a year-long study of the underwater soundscape of another Arctic coastal site, Cambridge Bay, Nunavut, was conducted over 2015. Unlike other Arctic locations considered to date, this site was louder when covered in ice with the loudest times occurring in April. Sounds of anthropogenic origin were found to dominate the soundscape with ten times more snowmobile traffic on ice than open water boat traffic. / Graduate

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Airborne lidar measurements of Arctic polar stratospheric clouds (PSCs) in January 1984 and January 1986 are reported. The locales and altitudes of the clouds coincided in both years with very cold ambient temperatures. During the 1984 experiment, PSCs were observed on three flights north of Thule, Greenland; peak backscatter occurred near 20 km (at temperatures below 193 K). A single PSC formation was seen between Iceland and Scotland during the 1986 experiment, with beak backscatter occurring near 22 km (at temperatures from 188-191 K). A sequence of observations in this same area by the SAM II satellite sensor depicts the history of cloud development and dissipation. Enhancements in aerosol backscattering in excess of a factor of 100 were measured during the 1984 experiment at latitudes near the Pole where 50-mb temperatures approached the frost point. Depolarization in the backscattered signal was estimated as 30-40%, similar to that measured in cirrus clouds. Farther south, with 50-mb temperatures several degrees warmer, backscatter enhancement factors ranged from 20-30, and little or no depolarization was observed. Results similar to the latter were found during the 1986 experiment--enhancement factors near 50 (at the 30-mb level, with temperatures 3-5 K above the frost point), and little depolarization. The contrast in observations suggested the existence of distinct cloud growth regimes delineated by temperatures, as proposed in recent articles addressing Antarctic ozone depletion. A theoretical model was developed which interposes a stage of nitric acid trihydrate deposition between the two stages of cloud formation and growth assumed in earlier models (aerosol droplet precursors and ice particles). The calculated temperature dependence of backscatter and extinction agreed well with experimentally observed values, except for small systematic errors at the 30-mb level which may be due to poor characterization of the temperature field there. A companion theoretical study of PSC formation at 70 mb in the Antarctic showed that about 80% and 30% of the nitric acid and water vapor supplies, respectively, may be sequestered in relatively large (4-μm radius) cloud particles at a temperature near 189 K. Such large particles would fall at a rate of about 2 km wk⁻¹, suggesting that PSCs may act as a sink for these stratospheric trace gases.

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No description available.