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10.
In the Willamette River, OR, main channel temperatures can be too warm for cold water fishes, causing fish to concentrate in secondary channel features that provide thermal refugia. However, temperature regimes vary among and within features. Improved understanding of physical processes controlling thermal regimes is needed. This study developed a dimensionless index for assessment of thermal refugia on the upper Willamette River. The novel hyporheic insolation (HIN) index uses minimal field measurements to predict thermal refugia resulting from buffering. Continuous water temperature measurements at one side channel, eight alcoves, and six beaver ponds provided data to ground truth calculated predictions. Water temperature records were first used to characterize stratification at sites. Calculation of the Richardson number, an index of stability, showed two well-mixed sites and 13 stratified sites. At stratified sites, calculated values characterized the ratio of cooling flux from hyporheic discharge to heat flux from incoming solar radiation. As increased, measured temperatures at sites decreased. Despite overall scatter, a logarithmic fit to bin-averaged values showed R2 = 0.91. Calculations suggest that secondary channel features characterized by stratification and cool hyporheic discharge can provide thermal refugia. Accordingly, the HIN index may serve as a practical tool grounded in physical processes governing temperature across a floodplain. 相似文献
11.
Wellbore integrity is one of the key performance criteria in the geological storage of CO 2. It is significant in any proposed storage site but may be critical to the suitability of depleted oil and gas reservoirs that may have 10’s to 1000’s of abandoned wells. Much previous work has focused on Portland cement which is the primary material used to seal wellbore systems. This work has emphasized the potential dissolution of Portland cement. However, an increasing number of field studies (e.g., Carey et al., 2007), experimental studies (e.g., Kutchko et al., 2006) and theoretical considerations indicate that the most significant leakage mechanism is likely to be flow of CO 2 along the casing–cement microannulus, cement–cement fractures, or the cement–caprock interface.In this study, we investigate the casing–cement microannulus through core-flood experiments. The experiments were conducted on a synthetic wellbore system consisting of a 5-cm diameter sample of cement that was cured with an embedded rectangular length of steel casing that had grooves to accommodate fluid flow. The experiments were conducted at 40 C and 14 MPa pore pressure for 394 h. During the experiment, 6.2 l of a 50:50 mixture of supercritical CO 2 and 30,000 ppm NaCl-rich brine flowed through 10-cm of limestone before flowing through the 6-cm length cement–casing wellbore system. Approximately 59,000 pore volumes of fluid moved through the casing–cement grooves. Scanning electron microscopy revealed that the CO 2–brine mixture impacted both the casing and the cement. The Portland cement was carbonated to depths of 50–250 m by a diffusion-dominated process. There was very little evidence for mass loss or erosion of the Portland cement. By contrast, the steel casing reacted to form abundant precipitates of mixed calcium and iron carbonate that lined the channels and in one case almost completely filled a channel. The depth of steel corroded was estimated at 25– m and was similar in value to results obtained with a simplified corrosion model.The experimental results were applied to field observations of carbonated wellbore cement by Carey et al. (2007) and Crow et al. (2009) to show that carbonation of the field samples was not accompanied by significant CO 2–brine flow at the casing–cement interface. The sensitivity of standard-grade steel casing to corrosion suggests that relatively straight-forward wireline logging of external casing corrosion could be used as a useful indicator of flow behind casing. These experiments also reinforce other studies that indicate rates of Portland cement deterioration are slow, even in the high-flux CO 2–brine experiments reported here. 相似文献
12.
The six mainstem reservoirs in the Missouri River basin (MRB) are managed mainly to prevent flooding from snowmelt and heavy rainfall, a goal for which the interannual variabilities of precipitation ( ), evapotranspiration ( ), and surface air temperature ( ) are vitally important. We tested the hypothesis that under the expected higher variability owing to global climate change, the months with the highest contributions to the interannual variability of , , and in the MRB will remain unchanged and quantified likely temporal trends in these quantities. Using high-resolution, downscaled Coupled Model Intercomparison Project Phase 5 multi-model ensemble data sets, we compared the multi-year ratio of monthly and annual interannual variability and temporal trends in , , and during 2011–2020 with three future decades. Results showed that the 6 months with the highest interannual variability in and (April–September) are the same in all four decades. However, for , only 4 months (December–March) retain their status as highly variable throughout the four decades; September and October variability is exceeded by the variability in other months. This implies that, compared to and , the cyclical change in the probabilities of in the MRB is less stable under future global climate change. This finding can be used to consider the need to alter existing strategies for reservoir release while minimizing the likelihood of aggravating flooding below the reservoirs. 相似文献
13.
In the Upper Colorado River Basin (UCRB), there is a deep reliance on seasonal snowpack for maintenance of water resources. The term “snow drought” has recently emerged to describe periods of anomalously low snowpack. Unique seasonal patterns in precipitation and temperature that drive snow drought can have distinct hydrologic signatures, and these relationships have not been carefully studied in the UCRB. Here we examine snow drought with a new classification scheme using peak snow water equivalent (SWE) and the ratio of basin-wide modeled peak SWE to accumulated (onset to peak) precipitation (SWE/ P) that clusters snow drought years into three distinct groups—“warm,” “dry,” and “warm & dry”—that minimize within-group variance. Over the period 1916–2018, we identify 14 warm years ( = 160 mm; = 0.24), 24 dry years ( = 117 mm; = 0.35), and 21 warm & dry years ( = 94 mm; = 0.23). An elevation-based analysis reveals two distinct patterns: warm snow droughts see severe SWE reductions primarily at lower (<2600 m) elevations (65% at lower elevations, 37% overall), whereas “dry” scenarios exhibit a consistent reduction across all elevations (39% overall). Using naturalized streamflow data, we also differentiate snow droughts by their earlier streamflow timing and decreased peakedness (warm: 7 days, 2%; dry: 7 days, 2%; warm & dry: 13 days, 5%). This research provides new insights into snow drought patterns relevant for regional water management. 相似文献
14.
PIONEERS IN BRITISH PLANNING Gordon Cherry (Ed.) The Architectural Press, London, 1981. 232 pp with index and illustrations. Price £8.95 paperback. PLANNING PROCEDURES John Stephenson Northwood Books, 1982 Price £9.95 hardback, 192 pages INDUSTRIAL LOCATION POLICY FOR ECONOMIC REVITALISATION Morris L. Sweet Praeger, 1981 THE POLITICS OF TOWN PLANNING Gordon Cherry Longmans, 1982. 165 pp. THE POLITICS OF LOCAL GOVERNMENT IN THE UNITED KINGDOM Alan Alexander Longman, 1982, 143 pp. Price £3.95 paperback LAND USE AND LIVING SPACE Robin Best Methuen U.P., 1981 URBAN PROJECTS MANUAL A guide to preparing upgrading and new development projects accessable to low income groups. Forbes Davidson and Geoff Payne (Eds) University Press 1983 Price £7.50 LONDON'S GREEN BELT: CONTAINMENT IN PRACTICE Richard Munton George Allen & Unwin, 1983 OUTDOOR RECREATION AND RESOURCE MANAGEMENT John Pigram Croom Helm, 1983 THE IDEAL CITY — ITS ARCHITECTURAL EVOLUTION IN EUROPE Rosenau, H. Methuen & Co. Ltd., London & New York. Third Edition 1983. 195 pages illustrated. Hardback. ENVIRONMENTAL HAZARDS IN THE BRITISH ISLES A. H. Perry George Allen and Unwin, 1981 RECREATION AND RESOURCES: LEISURE PATTERNS AND LEISURE PLACES J. Allan Patmore Blackwell, 1983 相似文献
15.
URBANIZATION AND COMMUNITY BUILDING IN MODERN NORWAY J. S. Tortenson, M. F. Metcalfe, T. F. Rasmussen Urbana Press, Oslo 1985. 312 pp., figs and tables. REGIONAL DEVELOPMENT POLICY R. Riddell Gower, 1985. £18.50 REVIEW OF SERVICE INDUSTRIES: A GEOGRAPHICAL APPRAISAL P. W. Daniels Methuen, 1985. £27.50. ARABIC‐ISLAMIC CITIES: BUILDING AND PLANNING PRINCIPLES Besim Selim Hakim KPI Ltd., London, 1986. pp. 192. £46 (h/b) FIFTY YEARS OF LANDSCAPE DESIGN Sheila Harvey and Stephen Rettig The Landscape Press, 1985. £12.50 CAPABILITY BROWN AND THE EIGHTEENTH CENTURY ENGLISH LANDSCAPE Roger Turner Weidenfeld & Nicholson. £16.95. 相似文献
16.
LANDSCAPE PLANNING Tom Turner (The Built Environment Series: Hutchinson) No price given. TREE FORM, SIZE AND COLOUR A Guide to Selection, Planting and Design Bodfan Gruffydd E. & F. N. Spon, London 1987. £26.50. SPON'S LANDSCAPE HANDBOOK Edited by Derek Lovejoy & Partners E. & F. N. Spon Ltd., London. Third Edition, 1986. 相似文献
17.
The World Bank, 1991: Urban Policy and Economic Development, an agenda for the 1990s The World Bank, Washington DC, 87 pp. Global Cities: Post‐Imperialism and the Internationalization of London Anthony D. King Routledge, London, 1990. Planning, Politics and the State: Political Foundations of Planning Thought Nicholas Low Unwin Hyman, London, 1991, 313 pp. Britain's Changing Environment — from the Air Tim Baylis Smith and Susan Owens (Eds) Cambridge University Press. Price £25. ISBN 0521 327121 Envisioning Information Edward R. Tufte Graphic Press, UK PO Box 8, Godalming, Surrey GU7 3HB. Price £30. 126 pages. A Dictionary of Landscape G. A. Gaulty Avebury Technical, Aldershot, 1991. 309 pp. ISBN 185 6282 147. Planning Law Practice and Precedents Stephen Tromans and Robert Turrall‐Clark Sweet & Maxwell, 1991; loose leaf. £135. 1006 pages. 相似文献
19.
ENGLISH STRUCTURE PLANNING Eds: D. T. Cross and M. R. Bristow Pion Ltd., London, 1983. £16.00. AN INTRODUCTION TO URBAN RENEWAL Michael S. Gibson and Michael J. Longstaff London: Hutchinson, 1982. 384 pp. INTEGRATED URBAN MODELS S. H. Putman Pion Ltd., 1983, 332 pp. EXPLANATION PREDICTION AND PLANNING: THE LOWRY MODEL M. T. Webber Pion Ltd., London, 1984, 214 pp. THE GOVERNMENT AND ADMINISTRATION OF METROPOLITAN AREAS IN WESTERN DEMOCRACIES Alan Norton Institute of Local Government Studies, University of Birmingham, 1983, 57 pp. THE MANAGEMENT OF SEMI‐NATURAL WOODLAND County Planning Officers’ Society (available from Hampshire County Planning Dept., price £2.00). 相似文献
20.
Traffic Mix Model (TRRU Research Report No. 30). A Methodology for Estimating Recreation Traffic Flows. August 1977, University of Edinburgh. 144 pps. “Recreation in the Highlands and Islands” Tourism and Recreation Research Unit, University of Edinburgh, December 1976. Research Report No. 22, 411pp with tables and diagrame; Research Report No. 31, 145 with tables and diagrams. Tourism and Recreation in the Chichester Area: a basis for planning Tourism and Recreation Research Unit, Research Report No. 35, University of Edinburgh. The Real Wealth of Nations S. R. Eyre Arnold, London, 1978. £7.95. Landscape Construction M. F. Downing E. & F. N. Spon, London, 1977 Planning and Organizing for Social Change. Action Principles from Social Science Research. Jack Rothman Columbia University Press. 628 p.p. Models and Cities and Regions A. G. Wilson, P. H. Rees, C. M. Leigh (editors) 1977 Wiley, £12.75. Ecology and Ekistics C. A. Doxiadis Edited by Gerald Dix Paul Elek, London 1977. Environmental Studies Series. 91 p.p. Paperback. £3.75. Tackling Urban Deprivation : The Contribution of Area‐Based Management T. Mason, K. Spencer, C. Vielba and B. Webster Institute of Local Government Studies, University of Birmingham, Dec. 1977. 93p.p. No price stated. Marketing Geography : with special reference to retailing R. L. Davies Methuen, 1976. £3.45. “Public Participation in Planning” Edited by W. R. D. Sewell and J. T. Coppock J. Wiley & Sons Ltd., Chichester, 1977. 208 p.p. £9.00. “The Individual Citizen and Public Participation” William Hampton and Raymond Walker Linked Research Project into Structure Planning, Interim Research Paper. 13, 1978. 24 p.p. £1.00. A Future for Planning Science Fiction Cities Town Planning discussion paper No. 27. Stephen Wood U.C.L. 1977. “The Bicycle Planning Book “ Mike Hudson (editor) Open Books Publishing Ltd. and Friends of the Earth, 1978. Paperback, £1.95. Residential Location and Urban Housing Markets G. K. Ingram (1977) (ed.) Cambridge, Mass : Ballinger Publishing Co., for the National Bureau of Economic Research. 相似文献
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