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171.
Victoria A. Sinclair Stephen E. Belcher Suzanne L. Gray 《Boundary-Layer Meteorology》2010,134(3):387-409
We report the characteristics of the three-dimensional, time evolving, atmospheric boundary layer that develops beneath an
idealised, dry, baroclinic weather system. The boundary-layer structure is forced by thermal advection associated with the
weather system. Large positive heat fluxes behind the cold front drive a vigorous convective boundary layer, whereas moderate
negative heat fluxes in the warm sector between the cold and warm fronts generate shallow, stably stratified or neutral boundary
layers. The forcing of the boundary-layer structure is quantified by forming an Eulerian mass budget integrated over the depth
of the boundary layer. The mass budget indicates that tropospheric air is entrained into the boundary layer both in the vicinity
of the high-pressure centre, and behind the cold front. It is then transported horizontally within the boundary layer and
converges towards the cyclone’s warm sector, whence it is ventilated out into the troposphere. This cycling of air is likely
to be important for the ventilation of pollution out of the boundary layer, and for the transformation of the properties of
large-scale air masses. 相似文献
172.
Julie A. Winkler Suzanne Thornsbury Marco Artavia Frank-M. Chmielewski Dieter Kirschke Sangjun Lee Malgorzata Liszewska Scott Loveridge Pang-Ning Tan Sharon Zhong Jeffrey A. Andresen J. Roy Black Robert Kurlus Denys Nizalov Nicole Olynk Zbigniew Ustrnul Costanza Zavalloni Jeanne M. Bisanz Géza Bujdosó Lesley Fusina Yvonne Henniges Peter Hilsendegen Katarzyna Lar Lukasz Malarzewski Thordis Moeller Roman Murmylo Tadeusz Niedzwiedz Olena Nizalova Haryono Prawiranata Nikki Rothwell Jenni van Ravensway Harald von Witzke Mollie Woods 《Climatic change》2010,103(3-4):445-470
A conceptual framework for climate change assessments of international market systems that involve long-term investments is proposed. The framework is a hybrid of dynamic and static modeling. Dynamic modeling is used for those system components for which temporally continuous modeling is possible, while fixed time slices are used for other system components where it can be assumed that underlying assumptions are held constant within the time slices but allowed to vary between slices. An important component of the framework is the assessment of the “metauncertainty” arising from the structural uncertainties of a linked sequence of climate, production, trade and decision-making models. The impetus for proposing the framework is the paucity of industry-wide assessments for market systems with multiple production regions and long-term capital investments that are vulnerable to climate variations and change, especially climate extremes. The proposed framework is pragmatic, eschewing the ideal for the tractable. Even so, numerous implementation challenges are expected, which are illustrated using an example industry. The conceptual framework is offered as a starting point for further discussions of strategies and approaches for climate change impact, vulnerability and adaptation assessments for international market systems. 相似文献
173.
Currently, the effect of dike breaches on downstream discharge partitioning and flood risk is not addressed in flood safety assessments. In a bifurcating river system, a dike breach may cause overland flows which can change downstream flood risk and discharge partitioning. This study examines how dike breaches and overflow affect overland flow patterns and discharges of the rivers of the Rhine delta. For extreme discharges, an increase in flood risk along the river branch with the smallest discharge capacity was found, while flood risk along the other river branches was reduced. Therefore, dike breaches and resulting overland flow patterns must be included in flood safety assessments.
相似文献174.
Herbert W. Schnopper Eric Silver Stephen Murray Suzanne Romaine Simon Bandler Christine Jones William Forman Norman Madden Jeffery Beeman Eugene Haller Finn Christensen Niels Westergaard Juan Fabregat Victor Reglero Alvaro Gimenez Noah Brosch Elia Liebowitz Hagai Netzer Marco Barbera Alfonso Collura Salvatore Sciortino 《Astrophysics and Space Science》2001,276(1):49-65
The X-Ray Spectroscopic Explorer (XRASE) has a unique combination of features that will make it possible to address many of NASA's scientific goals. These include how galaxy clusters form, the physics and chemistry of the ISM, the heating of stellar coronae, the amount and content of intergalactic baryonic matter, the mass of black holes and the formation of disks and jets in AGN and galactic binaries. XRASE has a thin foil, multilayered telescope with a large collecting area up to 10 keV, especially in the Fe K region (1100 cm2). Its microcalorimeter array combines high energy resolution (7 eV at 6 keV) and efficiency with a field-of-view of 26 arcmin2 . A deep orbit allows for long, continuous observations. Monitoring instruments in the optical (WOM-X), UV (TAUVEX) and hard X-RAY (GRAM) bands will offer exceptional opportunities to make simultaneous multi-wavelength observations. 相似文献
175.
The paper explores intersections between the fashion and furniture industries as manifest across magazine, retail and manufacturing spaces. We argue that the temporality and spatiality of furniture have begun to shift. As a result, furniture retailers and manufacturers in Canada and the UK have been required to restructure their methods of operating. 相似文献
176.
Dominique Sorel Suzanne Lesage Susan Brown Kelly Millar 《Ground Water Monitoring & Remediation》2001,21(4):140-148
A first pilot-scale field experiment using vitamin B12 and reduced titanium was conducted in an in situ vertical circulation column at CFB Borden. The objective of the experiment was to test the applicability of the technology for restoring aquifer source zones contaminated by chlorinated solvents—tetrachloroethene (PCE) and 1,1,1-trichloroethane (1,1,1-TCA)—in a mixture of dense nonaqueous phase liquids (DNAPLs). Vitamin B12 promotes the reductive dechlorination of chlorinated organics. A highly reducing and slightly alkaline environment must be maintained (Eh < - 480 mV and 7 < pH < 9) to maximize the rate of degradation. In this field test, PCE and 1,1,1-TCA degraded to a limited extent under experimental conditions, with 1,1,1-TCA degrading more readily. Indigenous bacteria were found to metabolize citrate, which caused titanium to precipitate, limiting degradation. The addition of glucose at the end of a second field season effectively limited citrate degradation and helped recover the optimal redox potential by keeping reduced titanium in solution. A laboratory column was used to confirm field results. The column also produced a significant biomass, which provided an additional source of organic carbon onto which the solvents sorbed. 相似文献
177.
Suzanne Bayley Vernon D. Stotts Paul F. Springer John Steenis 《Estuaries and Coasts》1978,1(3):171-182
Submerged aquatic plant populations in the Susquehanna Flats of the Chesapeake Bay were followed for 18 years. An exotic species, eurasian water milfoil,Myriophyllum spicatum, increased dramatically from 1958 to 1962; at the same time the dominant native species declined. After 1962, milfoil populations declined and the native rooted aquatics gradually began to return to their former levels. In the late 1960's all species declined and in 1972 almost disappeared from the Susquehanna Flats. These fluctuations may have been related to several interrelated environmental factors in the Chesapeake Bay, including tropical storms, turbidity, salinity and disease. The utilization of the Susquehanna Flats by waterfowl appears to be related to the abundance and species composition of the submerged macrophytes present. 相似文献
178.
Raymond P. Morgan Suzanne B. Block Nancy I. Ulanowicz Cunera Buys 《Estuaries and Coasts》1978,1(4):255-258
Genetic variability for two popula-tions, Maine and Maryland, of the soft-shelled clam,Mya arenaria, was estimated from electrophoretic anal-yses of whole clams. Polymorphism (12.5% in Maine and 16.7% in Maryland clams) and heterozygosity per individ-ual (4.6% in Maine and 6.6% in Maryland) were low for the two populations based on 40 loci in Maine and 42 loci in MarylandMya. 相似文献
179.
Suzanne Y. Wass 《Contributions to Mineralogy and Petrology》1973,38(2):167-175
Dominant plagioclase (An59) and minor spinel form possible cumulates in alkali basaltic flows from the Southern Highlands, N.S.W. The mode of occurrence of the spinel, and the chemical composition of both the spinel and the plagioclase suggest the spinel originated by exsolution from plagioclase formed at high pressure. 相似文献
180.