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171.
172.
Jason F. Shogren 《Climatic change》2000,45(3-4):489-491
173.
Thermochron iButtons incorporate the latest in digital technology, making them smaller, less expensive, durable and potentially more reliable than many other temperature logging devices. The objective of this study was to test the accuracy of an inexpensive air temperature measurement system, composed of a Thermochron iButton and radiation shield. Sixty‐one iButtons were subjected to a sequence of two water baths (0 °C and 24·9 °C) to assess the absolute accuracy of the sensors. Five solar radiation shields were tested in a greenhouse setting to evaluate the reduction in radiative heating. Significant differences (p < 0·05) were detected between instruments subsequent to both water‐bath treatment analyses. The accuracy of the sensors was well within the manufacturer's stated specification of ±1·0 °C with a collective temperature variance of ±0·21 °C. Temperature responses generated by the Thermochron iButtons in different radiation shields were consistent, but varied significantly (p < 0·05) from 28 to 44 °C based on diurnal temperature ranges. Results indicate that the Thermochron iButton is an accurate, inexpensive alternative to more expensive temperature data‐logging systems, and is well suited for obtaining quality spatially distributed data for hydrologic and water quality investigations. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
174.
Vega Anthony J. Miller Paul W. Rohli Robert V. Heavilin Jason 《Natural Hazards》2021,105(2):1281-1297
Natural Hazards - Nuisance flooding (NF; also known as high-tide, or “sunny day” flooding) is an increasingly prevalent phenomenon afflicting coastal developments worldwide. NF often... 相似文献
175.
Xie Wan-li Guo Qianyi Wu Jason Y. Li Ping Yang Hui Zhang Maosheng 《Natural Hazards》2021,106(1):805-827
Natural Hazards - Loess landslides have complicated deformation mechanisms. Accurately describing the internal failure deformation of loess landslides and establishing a theoretical method of... 相似文献
176.
Natural Hazards - Research concerning the behavior of international linguistic minorities at institutions of higher education during disasters is very limited. Many international groups suffer from... 相似文献
177.
A multi-proxy lacustrine record of Holocene climate change on northeastern Baffin Island, Arctic Canada 总被引:3,自引:0,他引:3
Jason P. Briner Neal Michelutti Donna R. Francis Gifford H. Miller Yarrow Axford Matthew J. Wooller Alexander P. Wolfe 《Quaternary Research》2006,65(3):431-442
Reconstructions of past environmental changes are critical for understanding the natural variability of Earth's climate system and for providing a context for present and future global change. Radiocarbon-dated lake sediments from Lake CF3, northeastern Baffin Island, Arctic Canada, are used to reconstruct past environmental conditions over the last 11,200 years. Numerous proxies, including chironomid-inferred July air temperatures, diatom-inferred lakewater pH, and sediment organic matter, reveal a pronounced Holocene thermal maximum as much as 5°C warmer than historic summer temperatures from 10,000 to 8500 cal yr B.P. Following rapid cooling 8500 cal yr B.P., Lake CF3 proxies indicate cooling through the late Holocene. At many sites in northeastern Canada, the Holocene thermal maximum occurred later than at Lake CF3; this late onset of Holocene warmth is generally attributed to the impacts of the decaying Laurentide Ice Sheet on early Holocene temperatures in northeastern Canada. However, the lacustrine proxies in Lake CF3 apparently responded to insolation-driven warmth, despite the proximity of Lake CF3 to the Laurentide Ice Sheet and its meltwater. The magnitude and timing of the Holocene thermal maximum at Lake CF3 indicate that temperatures and environmental conditions at this site are highly sensitive to changes in radiative forcing. 相似文献
178.
A comparison of permafrost prediction models along a section of Trail Ridge Road, Rocky Mountain National Park, Colorado, USA 总被引:1,自引:0,他引:1
The distribution of mountain permafrost along Trail Ridge Road (TRR) in Rocky Mountain National Park, Colorado, was modeled using ‘frost numbers’ and a ‘temperature of permafrost model’ (TTOP) in order to assess the accuracy of prediction models. The TTOP model is based on regional observations of air temperature and heat transfer functions involving vegetation, soil, and snow; whereas the frost number model is based on site-specific ratios of ground temperature measurements of frozen and thawed degree-days. Thirty HOBO© temperature data loggers were installed near the surface as well as at depth (30 to 85 cm). From mid-July 2008 to 2010, the mean annual soil temperature (MAST) for all surface sites was − 1.5 °C. Frost numbers averaged 0.56; TTOP averaged − 1.8 °C. The MAST was colder on western-facing slopes at high elevations. Surface and deeper probes had similar MASTs; however, deeper probes had less daily and seasonal variation. Another model developed at the regional scale based on proxy indicators of permafrost (rock glaciers and land cover) classified 5.1 km2 of permafrost within the study area, whereas co-kriging interpolations of frost numbers and TTOP data indicated 2.0 km2 and 4.6 km2 of permafrost, respectively. Only 0.8 km2 were common among all three models. Three boreholes drilled within 2 m of TRR indicate that permafrost does not exist at these locations despite each borehole being classified as containing permafrost by at least one model. Addressing model uncertainty is important because nutrients stored within frozen or frost-affected soils can be released and impact alpine water bodies. The uncertainty also exposes two fundamental problems: empirical models designed for high latitudes are not necessarily applicable to mountain permafrost, and the presence of mountain permafrost in the alpine tundra of the Colorado Front Range has not been validated. 相似文献
179.
Jason Phillips 《Applied geography (Sevenoaks, England)》2012,32(2):376-392
The question of how sustainable a mining site is at the end of its operational life has been somewhat unanswered. The fundamental problem has been how to evaluate the sustainability of a mining site once operations cease and is abandoned. Environmental Impact Assessment (EIA) is certainly a way to evaluate sustainability of such sites, but only through inference and subjective evaluation. This is because the topic of sustainability still hotly debated, and is predominantly focussed on an anthropocentric approach. Even with quantitative-based EIAs, the question is how to directly evaluate sustainability from the data available using a consistent quantitative approach rather than on a case-by-case basis or subjective evaluation.However, by using the ideas and concepts concerning the coupled relationship between the environment and humans prevalent in sustainability science, the question of what is and how to evaluate sustainability has become capable of being answered. Based on previous work of the author in the development and application of a mathematical model of sustainability, the paper applies the model to the results of a quantitative EIA evaluation for nine clusters of abandoned limestone quarries located in the southern Palestinian West Bank.The results indicate that seven of the nine clusters were deemed to be unsustainable, whilst the other two clusters were considered as sustainable at a very weak level only. The results are discussed within the broader context of the coupled environment-human system using one of the supporting frameworks for the development and application of the mathematical model of sustainability: Earth System Analysis. Within this context, the discussion indicates the fact that unmanaged impacts by humans has created the situation for unsustainability to occur. The paper therefore provides for the clearest indication yet of the nature of sustainability at the end of the mining operational life-cycle without an effective and proper management strategy or policies. 相似文献
180.
We investigate the internal thermal evolution of Kuiper belt objects (KBOs), small (radii <1000 km), icy (mean densities ) bodies orbiting beyond Neptune, focusing on Pluto's moon Charon in particular. Our calculations are time-dependent and account for differentiation. We review evidence for ammonia hydrates in the ices of KBOs, and include their effects on the thermal evolution. A key finding is that the production of the first melt, at the melting point of ammonia dihydrate, ≈176 K, triggers differentiation of rock and ice. The resulting structure comprises a rocky core surrounded by liquids and ice, enclosed within a >100-km thick undifferentiated crust of rock and ice. This structure is especially conducive to the retention of subsurface liquid, and bodies the size of Charon or larger (radii >600 km) are predicted to retain some subsurface liquid to the present day. We discuss the possibility that this liquid can be brought to the surface rapidly via self-propagating cracks. We conclude that cryovolcanism is a viable process expected to affect the surfaces of large KBOs including Charon. 相似文献