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201.
Stewart Cohen Denise Neilsen Scott Smith Tina Neale Bill Taylor Mark Barton Wendy Merritt Younes Alila Philippa Shepherd Roger Mcneill James Tansey Jeff Carmichael Stacy Langsdale 《Climatic change》2006,75(3):331-358
The research activity described in this report is a comprehensive regional assessment of the impacts of climate change on
water resources and options for adaptation in the Okanagan Basin. The ultimate goal of the project is to develop integrated
climate change and water resource scenarios to stimulate a multistakeholder discussion on the implications of climate change
for water management in the region.
The paper describes two main objectives: (a) providing a set of research products that will be of relevance to regional interests
in the Okanagan, and (b) establishing a methodology for participatory integrated assessment of regional climate change impacts
and adaptation that could be applied to climate-related concerns in Canada and other countries.
This collaborative study has relied on field research, computer-based models, and dialogue exercises to generate an assessment
of future implications, and to learn about regional views on the prospects for adaptation. Along the way, it has benefited
from strong partnerships with governments, researchers, local water practitioners, and user groups. Building on the scenario-based
study components, and a series of interviews and surveys undertaken for the water management and adaptation case study components,
a set of stakeholder dialogue sessions were organized which focused on identifying preferred adaptation options and processes
for their implementation. Rather than seeking consensus on the “best” option or process, regional interests were asked to
consider a range of available options as part of an adaptation portfolio that could address both supply side and demand side
aspects of water resources management in the Okanagan.
The Canadian Crown reserves the right to retain a non-exclusive, royalty free licence in and to any copyright. 相似文献
202.
L. Mahrt Dean Vickers Jim Edson James M. Wilczak Jeff Hare Jørgen Højstrup 《Boundary-Layer Meteorology》2001,100(1):47-61
The adjustment of the boundary layer immediately downstream froma coastline is examined based on two levels of eddy correlation data collected on a mast at the shore and six levels of eddy correlation data and profiles of mean variables collected from a mast 2 km offshore during the Risø Air-Sea Experiment. The characteristics of offshore flow are studied in terms of case studies and inter-variable relationships for the entire one-month data set. A turbulent kinetic energy budget is constructed for each case study.The buoyancy generation of turbulence is small compared to shear generation and dissipation. However, weakly stable and weakly unstable cases exhibit completely different vertical structure. With flow of warm air from land over cooler water, modest buoyancy destruction of turbulence and reduced shear generation of turbulence over the less rough sea surface cause the turbulence to rapidly weaken downstream from the coast. The reduction of downward mixing of momentum by the stratification leads to smaller roughness lengths compared to the unstable case. Shear generation at higher levels and advection of stronger turbulence from land often lead to an increase of stress and turbulence energy with height and downward transport of turbulence energy toward the surface.With flow of cool air over a warmer sea surface, a convective internal boundary layer develops downstream from the coast. An overlying relatively thick layer of downward buoyancy flux (virtual temperature flux) is sometimes maintained by shear generation in the accelerating offshore flow. 相似文献
203.
Robert L Cullers Sambhudas Chaudhuri Bill Arnold Moon Lee Carlton W Wolf 《Geochimica et cosmochimica acta》1975,39(12):1691-1703
The REE (rare earth element) content of a wide variety of clay mineral groups have been analyzed using radiochemical neutron activation and have been found to be quite variable in absolute REE content (range of ∑REE = 5.4–1732) and less variable in relative REE content (range of chondritenormalized La/Lu = 0.9–16.5). The variable REE content of the clay mineral groups is probably determined by the REE content of the source rock from which the clay mineral was derived and not from the separate minerals in the rock.The clay-sized fractions of the Havensville and Eskridge shales of Kansas and Oklahoma have similar relative REE distributions and identical negative Eu anomaly size as the composite of NAS (N. American shales), but an absolute REE content (range of ∑REE = 46–348) that may differ significantly from the composite of NAS. The clay-sized fraction of samples from any given outcrop did not vary much in absolute or relative REE content, but samples from northern Oklahoma, probably composed of continental to near-shore marine sediments, have higher absolute REE contents and higher La/Lu ratios than samples of marine deposits in Kansas (e.g. mean ∑REE in Oklahoma = 248; mean ∑REE in Kansas = 69–116). The differencess in the REE content between samples in Oklahoma and Kansas may be caused by chemical weathering processes in the source area, exchange reactions in the environment of deposition, or diagenesis and do not appear to be a result of the different clay minerals.Most samples have Eu anomalies relative to chondrites (range of Eu/Sm ratios of samples = 0.035–1.17; chondrites = 0.35). Some montmorillonites and kaolinites are anomalous in Eu relative to the NAS (range of Eu/Sm ratios of samples = 0.056–0.21; NAS = 0.22). These anomalies may be inherited from source rocks with Eu anomalies originally produced by igneous processes, or they may be produced by chemical weathering processes in the source area. 相似文献
204.
G. Lain Ellis Glenn A. Goodfriend James T. Abbott P. E. Hare David W. Von Endt 《Geoarchaeology》1996,11(3):189-213
Detailed racemization analyses were carried out on samples of the land snail Rabdotus mooreanus from archaeological sites at Fort Hood, in central Texas. D -alloisoleucine/L -isoleucine (A/I) values were determined for 260 individual shells from 29 proveniences, including sites in alluvium, colluvium, and rockshelters, as well as burned rock middens. A/I values show a good correlation with radiocarbon age, and so provide reasonably precise estimates of ages. Analyses indicate the presence of redeposited material in a large number of proveniences. These result from sedimentary processes involved in burial of the sites as well as from later disturbance (aboriginal or recent) of site stratigraphy. Because amino acid racemization analyses are relatively easy to carry out, this method lends itself to very detailed chronostratigraphic analyses of archaeological sites, thus permitting assessment of site integrity and assisting in the interpretation of site formation processes. © 1996 John Wiley & Sons, Inc. 相似文献