Empirical modelling of site-specific errors in continuous GPS data   总被引：2，自引：2，他引：0  

Michael Moore  Christopher Watson  Matt King  Simon McClusky  Paul Tregoning 《Journal of Geodesy》2014,88(9):887-900

Continuous global positioning system (GPS) stations propagate biases and spurious signals into the derived parameter time series when the measurements are subject to site-specific effects, such as multipath. This is a particular problem in the investigation of geophysical and atmospheric phenomena where signals may be small in magnitude. A methodology to remove these erroneous signals from long-term time series will significantly increase the usefulness of the derived time series. This work provides the theoretical basis for use of an empirical site model (ESM) derived from post-fit phase residuals to mitigate unmodelled site-specific errors. Additionally, we also investigate the effectiveness of applying an ESM to a regional GPS network and a short baseline solution. Under most observing scenarios, we show that the ESM approach is predicted to improve the precision and accuracy of the site coordinates. However, it is important to note that we found some scenarios where the ESM can introduce a bias. For instance, when the antenna is mounted close to the ground. In this scenario, for a short baseline, we observed the introduction of a 4-mm bias in height. Use of an ESM for the same short baseline with an uncalibrated radome substantially improves the results by removing a large bias of over 10 mm in height. Similarly, application of an ESM derived from historic data yields similar improvements. This demonstrates that the ESM can be a powerful tool when applied to appropriate site-specific configurations and could potentially be implemented in routine GPS analysis for a broad range of applications.  相似文献   

Equipped to deal with uncertainty in climate and impacts predictions: lessons from internal peer review   总被引：1，自引：0，他引：1  

Anna Wesselink  Andrew Juan Challinor  James Watson  Keith Beven  Icarus Allen  Helen Hanlon  Ana Lopez  Susanne Lorenz  Friederike Otto  Andy Morse  Cameron Rye  Stephane Saux-Picard  David Stainforth  Emma Suckling 《Climatic change》2015,132(1):1-14

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Lessons from China: building technological capabilities for low carbon technology transfer and development     

Jim Watson  Rob Byrne  David Ockwell  Michele Stua 《Climatic change》2015,131(3):387-399

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Transgressions of the man on the moon: climate change,Indigenous expertise,and the posthumanist ethics of place and space     

Annette Watson  Orville Huntington 《GeoJournal》2014,79(6):721-736

Indigenous peoples have been enrolled in climate change research for decades, participating in data-gathering, as writing collaborators, and serving as the symbolic “canary in the coal mine” for public outreach and policy-making. They have indeed experienced some of the most rapid environmental changes, but rather than emphasize their vulnerabilities, we argue their expertise is narrowly understood in formulating knowledge; the research on climate change has a limited understanding of what it might mean to be inter- or trans-disciplinary because research is formulated exclusively through the assumptions of Enlightenment thought, without sufficiently engaging non-Western subjectivities. Qualitative social sciences and “Indigenous methodologies” can be used to better achieve trans-disciplinarity; in this article we re-tell a story told by Native elders from tribes across Alaska about the “man on the moon.” While literally referring to the US moon landing, elders invoke this story when addressing climate change: it teaches the ethics of the human-nature relationship, developed from a “more-than-human” (or “posthuman”) philosophy. Our data comes from participant-observation and oral history; we draw upon poststructuralist theory, and frame our analysis through the literatures of critical geography, science studies, and American Indian studies. To ensure that Indigenous peoples are not used as props in Western policy agendas, researchers must engage with non-Enlightenment intellectual traditions. More than being a source of data or a symbol of humanity’s ruin, Indigenous wisdom can productively inform sustainable policy agendas to adapt to climate change. What can be learned, for example, is a more-than-human ethics of place and space.  相似文献   

TitaniQ: a titanium-in-quartz geothermometer   总被引：21，自引：10，他引：11  

David A. Wark  E. Bruce Watson 《Contributions to Mineralogy and Petrology》2006,152(6):743-754

Titanium is one of many trace elements to substitute for silicon in the mineral quartz. Here, we describe the temperature dependence of that substitution, in the form of a new geothermometer. To calibrate the “TitaniQ” thermometer, we synthesized quartz in the presence of rutile and either aqueous fluid or hydrous silicate melt, at temperatures ranging from 600 to 1,000°C, at 1.0 GPa. The Ti contents of quartz (in ppm by weight) from 13 experiments increase exponentially with reciprocal T as described by: Application of this thermometer is straightforward, typically requiring analysis of only one phase (quartz). This can be accomplished either by EPMA for crystallization temperatures above 600°C, or by SIMS for temperatures down to at least 400°. Resulting temperature estimates are very precise (usually better than ±5°C), potentially allowing detailed characterization of thermal histories within individual quartz grains. Although calibrated for quartz crystallized in the presence of rutile, the thermometer can also be applied to rutile-absent systems if TiO₂ activity is constrained.  相似文献   

Temporospatial dynamics and public health significance of bacterial flora identified on a major leatherback turtle (Dermochelys coriacea) nesting beach in the Southern Caribbean          下载免费PDF全文

Ayanna Carla N. Phillips  Johanna Coutou  Stacy Rajh  Neville Stewart  Antonio Watson  Adam Jehu  Hamish Asmath  Francis Dziva  Chandrashekhar Unakal  Ridley Holder  Raymond Raoul Carthy 《Marine Ecology》2017,38(2)

Grande Riviere beach, on the island of Trinidad, supports the largest nesting population of leatherback turtles in the Caribbean region. Throughout the nesting season, nests are naturally disturbed by newly nesting females, resulting in egg breakage and loss of some nest viability. This environment is ideal for the growth and proliferation of microorganisms. The range of bacterial flora present in beach sand and egg shells was examined, with emphasis on bacteria that may pose a threat to public and animal health. The extent to which the bacterial load and genera on the beach changed throughout the season was also assessed. Twenty‐five genera were identified, with Pseudomonas spp. found to be the most predominant environmental bacteria. Four genera identified possess zoonotic potential, while five additional genera are known to be of public and animal health significance. Distinct shifts in the density and distribution of bacteria were observed along the beach from early to peak nesting season. Shifts were seen across heavily traversed zones, thus highlighting the potential exposure threats posed to beach visitors and animals alike. Further studies aimed at speciating this population of bacteria, as well as isolating potential fungal pathogens may mitigate this threat. Identification of bacterial agents that are specifically pathogenic to leatherback turtles, turtle eggs, hatchlings and those who may interact with these animals will serve to enhance and guide efforts to better conserve this species and protect the health of all who visit this ecologically significant site.  相似文献   

Book Reviews     

Patty Jo Watson 《Geoarchaeology》2008,23(1):173-175

The Neolithic revolution in the Near East: Transforming the human landscape. Alan H. Simmons, 2007, The University of Arizona Press, Tucson, Arizona, xvii +339 pp., $55.00 (cloth).  相似文献   

Remains of pingos in Wales and the Isle of Man     

E. Watson 《Geological Journal》1971,7(2):381-392

Remains of pingos have already been reported from east central Wales. This paper records a further group from west central Wales and a probable group from the Isle of Man. When they are compared with contemporary pingos it is clear that they belong to the open system type, which, in contrast with the solitary pingo of the closed system type, tends to occur in clusters of mutually interfering forms and on melting to result in a complex pattern of ramparts. Much of the recently discovered group in central Wales shows this complexity and suggests later pingos developing on the sites of earlier ones as the injection centres migrated upslope. On more open sites simpler solitary pingos occur, including some elongated forms. The Isle of Man group consists of depressions without ramparts but their location and orientation suggest they represent pingo basins. It is argued that although the most convincing evidence for pingos consists of arcuate to annular ramparts enclosing basins, the ramparts may disappear through cultivation.  相似文献