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171.
Making local futures tangible—Synthesizing, downscaling, and visualizing climate change scenarios for participatory capacity building 总被引:1,自引:0,他引:1
Alison Shaw Stephen Sheppard Sarah Burch David Flanders Arnim Wiek Jeff Carmichael John Robinson Stewart Cohen 《Global Environmental Change》2009,19(4):447-463
Local in its causes and global in its impacts, climate change still poses an unresolved challenge for scientists, politicians, entrepreneurs, and citizens. Climate change research is largely global in focus, aims at enhanced understanding, and is driven by experts, all of which seem to be insufficient to anchor climate change action in regional and local contexts. We present results from a participatory scenario study conducted in collaboration with the municipality of Delta in SW British Columbia, Canada. This study applies a participatory capacity building approach for climate change action at the local level where the sources of emissions and the mechanisms of adaptation reside and where climate change is meaningful to decision-makers and stakeholders alike. The multi-scale scenario approach consists of synthesizing global climate change scenarios, downscaling them to the regional and local level, and finally visualizing alternative climate scenarios out to 2100 in 3D views of familiar, local places. We critically discuss the scenarios produced and the strengths and weaknesses of the approach applied. 相似文献
172.
Michael H. Robinson Clark R. Alexander Chester W. Jackson Christopher P. McCabe David Crass 《Geoarchaeology》2010,25(3):312-326
Archaeological sites in beach and estuarine environments are continually threatened by diverse natural marine processes. Shoreline erosion, bluff retreat, and sea level rise all present potential for site destruction. Using historic maps, aerial imagery, and field survey methods in a GIS, 21 potentially significant archaeological sites on Georgia barrier islands were selected for determination of site‐specific rates of shoreline change using a powerful, new, moving‐boundary GIS analysis tool. A prioritized list of sites, based on the order of site loss from erosion, was generated to assist coastal managers in identifying and documenting sites most at risk. From the original selection of 21 sites, 11 sites were eroding, 8 shorelines were stable, and 2 shorelines were accreting. The methodology outlined here produces critical information on archaeological site loss rates and provides a straightforward means of prioritizing sites for detailed documentation. © 2010 Wiley Periodicals, Inc. 相似文献
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An Evaluation of Methods for the Chemical Decomposition of Geological Materials for Trace Element Determination using ICP-MS 总被引:3,自引:0,他引:3
Zongshou Yu Philip Robinson Peter McGoldrick 《Geostandards and Geoanalytical Research》2001,25(2-3):199-217
Complete dissolution is essential to obtain accurate analytical results using ICP-MS. In this study, decomposition techniques (i.e. acid digestions using Savillex Teflon vials, a high pressure digestion system and microwave oven, a combined lithium tetraborate fusion - HF/HNO3 acid decomposition and sodium peroxide sinter) for the total dissolution of different types of geological reference materials have been investigated. Savillex Teflon vial HF/HNO3 digestion is effective for basaltic samples. The high pressure HF/HClO4 digestion (PicoTrace TC-805 digestion system, Bovenden, Germany) allows dissolution of basalts and ironstones. Granites and magnetite-rich samples can be dissolved using a high pressure HF/H2 SO4 method. Geological samples cannot be effectively attacked by microwave acid digestion. A combined lithium tetraborate fusion - HF/HNO3 acid digestion method allows complete dissolution of many different types of geological materials; however, this method precludes the determination of volatile elements due to the high fusion temperature (1000 °C). A sodium peroxide sinter method at 480 °C has the potential for the rapid determination of Y, Sc and REE in different types of geological materials. However, the lack of ultra-pure reagents precludes the use of lithium tetraborate fusion and sodium peroxide sinter methods for the measurement of geological samples with low trace element abundances. 相似文献
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The impact of land use change on water resources in sub-Saharan Africa: a modelling study of Lake Malawi 总被引:1,自引:0,他引:1
Ian R. Calder Robin L. Hall Heidi G. Bastable Henry M. Gunston Osborne Shela Amon Chirwa Robinson Kafundu 《Journal of Hydrology》1995,170(1-4):123-135
A modelling study to investigate the effects of land use change from natural forest to agricultural land on large-scale catchment runoff in southern Africa is described. The evaporative component of the model considers the catchment to be composed of one of three surface types—forest, agricultural land or water surface. Values of the model parameters for the forest and agricultural lands were obtained from experimental studies carried out in the dry zone of India. Estimates of average monthly potential evaporation, together with measurements of monthly rainfall, were used in the model to predict the monthly levels of Lake Malawi. These were compared with observed levels. From 1896 to 1967 the major fluctuations in lake level, both seasonally and annually, are well described by this model (excepting the period from 1935 to 1945, immediately following the time when there was no outflow from the lake) using a value of 64% for the forest coverage of the catchment. The overall agreement between prediction and observation indicates that variations in rainfall alone, without changes in either evaporative demand or in the hydraulic regime of the lake, are sufficient to explain lake level changes. For the more recent period (1954–1994), model predictions of lake level which take into account a decrease in forest cover of 13% over the period 1967–1990 (consistent with the actual decrease in forest cover for this period) agree well with observations both annually and seasonally. Without this decrease in forest cover, the model predicted that the lake level would have been about 1 m lower than that observed during the southern African drought of 1992. The model, in conjunction with real-time rainfall data obtained from land-based gauges, radar or satellite observations, can be used for real-time water resource management applications such as the operation of barrages regulating the flow from Lake Malawi or for the issuing of flood or drought warnings. 相似文献
179.
History of forest hydrology 总被引:24,自引:0,他引:24
Hydrology as a science and a technology is examined, as are some of the myths on the role of forests in hydrology and water resources. The history of catchment area research is traced, in Europe, in the USA and in East Africa, with particular reference to forest hydrology and, in the earlier years, to water quantity rather than water quality. The importance of associating physical process studies with hydrological systems' investigations, to enhance understanding of why particular catchments behave as they do, is stressed. Recent advances in hydrochemistry have been exploited to elucidate water flow paths within experimental catchments. Stimulated by requirements for research into acidification of surface waters, research catchments have proved to be valuable outdoor laboratories from which a much improved understanding of the flow processes has been achieved. Conflicting claims about the impacts of forestry are described and discussed. 相似文献
180.
T. R. Robinson 《Annales Geophysicae》1994,12(4):316-332
Physical processes which affect the absorption of radio waves passing through the auroral E-region when Farley-Buneman irregularities are present are examined. In particular, the question of whether or not it is legitimate to include the anomalous wave-enhanced collision frequency, which has been used successfully to account for the heating effects of Farley-Buneman waves in the auroral E-region, in the usual expression for the radio-wave absorption coefficient is addressed. Effects also considered are those due to wave coupling between electromagnetic waves and high-frequency electrostatic waves in the presence of Farley-Buneman irregularities. The implications for radio-wave heating of the auroral electrojet of these processes are also discussed. In particular, a new theoretical model for calculating the effects of high-power radio-wave heating on the electron temperature in an electrojet containing Farley-Buneman turbulence is presented. 相似文献