Dartmoor's overlooked glacial legacy     

David J.A. Evans  Stephan Harrison  Andreas Vieli  Ed Anderson 《Geology Today》2012,28(6):224-229

Traditionally regarded as a relict permafrost and periglacial landscape that lay beyond the limits of Pleistocene glaciation, the granite uplands of northern Dartmoor in south‐west England in fact contain geomorphological evidence for the former existence of a plateau ice cap, making the area the location of the southernmost independent glacier mass in the British Isles. In addition to weakly U‐shaped valleys, the most prominent evidence comprises arcuate and linear bouldery ridges and hummocky valley floor drift, which are interpreted as latero‐frontal moraines deposited by the outlet glacier lobes of a plateau ice cap. Inset sequences of these depositional landforms, in association with meltwater channels, demarcate the receding margins of the glacier lobes. A numerical model of ice cap development shows that a predominantly thin plateau icefield type glaciation is required in order to produce significant ice flow into surrounding valleys. The highest and most extensive plateau areas were occupied by ice for the longest cumulative period of time throughout the Pleistocene, thereby explaining: (1) the lack of tors in such areas as the product of ‘average’ glacial conditions preferentially removing tors or dampening their production rates, (2) the survival of high relief tors during glaciation if they occupied summits too narrow to develop thick and erosive glacier ice, and (3) the survival of subdued tors in areas glaciated less regularly during the Pleistocene.  相似文献   

DISCUSSION OF "An Economical Approach to Determining the Extent of Ground-Water Contamination and Formulating a Contaminant Removal Plan", by Kiyoshi W. Mido, January-February issue, v. 19, no. 1, pp. 41–47     

David S. Ward  Ed Tang 《Ground water》1981,19(5):552-553

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Comparison of the turbulent transfer processes near the surface     

Gordon A. McBean 《Boundary-Layer Meteorology》1973,4(1-4):265-274

In order to parameterize the surface fluxes, it is desirable first to understand the turbulent transfer processes. In this paper the spectral correlation coefficients for momentum, heat and moisture transfer from the Ladner, BOMEX and Suffield experiments are compared. Near-neutral to unstable stratifications were examined. Differences between heat and momentum transfer processes were found and the differences increased with instability. The transfer of a passive scalar, such as moisture was found to be dependent on the active-scalar/passive-scalar correlation.  相似文献   

A Modified Radial Diagram Approach for Evaluating Natural Attenuation Trends for Chlorinated Solvents and Inorganic Redox Indicators     

Grant R. Carey  Paul J. Van  Geel  Todd H. Wiedemeier  Edward A. McBean 《Ground Water Monitoring & Remediation》2003,23(4):75-84

Selection of monitored natural attenuation as a ground water remedy requires that sound scientific documentation clearly illustrating the effectiveness of this remedial alternative be presented to regulatory agencies and concerned citizens. An innovative radial diagram approach is applied to illustrate natural attenuation trends for total benzene, toluene, ethylbenzene, and xylenes (BTEX) and chlorinated ethenes at a former fire training area at Pittsburgh Air Force Base, New York. A BTEX-CAH (chlorinated aliphatic hydrocarbons) radial diagram map shows that concentrations of site contaminants are generally decreasing along the primary flowpath downgradient from the source area. This radial diagram map also suggests that there is a spatial correlation between decreasing CAH parent compound concentrations and increasing or stable daughter product concentrations. This provides secondary evidence of intrinsic biodegradation of TCE downgradient from the source area. A SEQUENCE-Redox™ map suggests that there is a spatial correlation between trends in electron acceptor and metabolic byproduct concentrations, and the decline in total BTEX concentrations downgradient from the source area. This correlation provides secondary evidence for the intrinsic biodegradation of total BTEX in the aquifer. This study demonstrates that radial diagram visual aids can provide a clear and efficient approach for documenting natural attenuation lines of evidence, as an alternative or a complement to using multiple contour maps, tabulated data, or log-linear plots.  相似文献   

Climate Change and Extreme Weather: A Basis for Action   总被引：2，自引：0，他引：2  

McBean  Gordon 《Natural Hazards》2004,31(1):177-190

The economic and social costs of extreme weather-related events have been increasing around the globe. There is some debate over how much of this past increase has been due to social factors and how much due to changes in frequency or characteristics of extreme events. The Intergovernmental Panel on Climate Change (2001a) has affirmed that humans are having a role in changing the climate and will have a larger role in the future. Although the changes in extreme events are by their nature both difficult to detect and difficult to model, the consensus is that there will be changes in the future. Through a risk-based decision-making analysis, it is concluded that society should make the additional investments to reduce vulnerability to this increased risk.  相似文献   

Book reviews     

Michael Ed. Hohn  Melanie A. Wetzel  James R. Carr  W. E. Sharp  C. John Mann 《Mathematical Geology》1995,27(2):301-313

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Suffer a Sea Change? Contrasting perspectives towards urban policy and migration in coastal Australia     

Nicole Gurran  Ed Blakely 《The Australian geographer》2007,38(1):113-131

Has the notion of ‘sea change’ and its considerable implications for non-metropolitan coastal Australia been exaggerated? In this article alternative perspectives of ‘sea change’ in Australia are reviewed, and the policy implications of each assessed. One perspective regards migration to coastal areas beyond the capital cities as incidental to continued metropolitan primacy and unlikely to affect or change Australia's overall urban or economic structure. The other considers the movement as a significant and enduring process with major environmental and socio-economic repercussions. With reference to research conducted for the National Sea Change Taskforce, the article finds partial support for both positions, leading to a more revealing understanding of ‘sea change’ in Australia. A set of policy responses, sensitive to the particular qualities of Australian coastal environments and communities, are proposed for consideration by all three tiers of government.  相似文献   

Asymmetric measures of association, closed data, and multivariate analysis     

Michael Ed. Hohn  Edward B. Nuhfer 《Mathematical Geology》1980,12(3):235-246

The association between constant-sum variables X_i and X_j expressed as percentages can be calculated as a product-moment correlation between X_i and X_j/(100 – X_i ) and a correlation between X_j and X_i/(100 – X_j ). An asymmetric, square matrix may be formed from these coefficients, and multivariate analysis performed by two methods: singular value decomposition and canonical decomposition. Either analysis avoids problems in the interpretation of correlation coefficients determined from closed arrays, and provides information about dependencies among the variables beyond that obtained from the usual correlation coefficient between X_i and X_j.Two examples show the canonical decomposition to have the greater usefulness.  相似文献   

Upholding labour productivity under climate change: an assessment of adaptation options     

Ed Day  Nick Kingsmill  Hélia Costa  Anna Mavrogianni 《Climate Policy》2019,19(3):367-385

Changes in labour productivity feed through directly to national income. An external shock, like climate change, which may substantially reduce the productivity of workers is therefore a macroeconomic concern. The biophysical impact of higher temperatures on human performance is well documented. Less well understood are the wider effects of higher temperatures on the aggregate productivity of modern, diversified economies, where economic output is produced in contexts ranging from outdoor agriculture to work in air-conditioned buildings. Working conditions are at least to some extent the result of societal choices, which means that the labour productivity effects of heat can be alleviated through careful adaptation. A range of technical, regulatory/infrastructural and behavioural options are available to individuals, businesses and governments. The importance of local contexts prevents a general ranking of the available measures, but many appear cost-effective. Promising options include the optimization of working hours and passive cooling mechanisms. Climate-smart urban planning and adjustments to building design are most suitable to respond to high base temperature, while air conditioning can respond flexibly to short temperature peaks if there is sufficient cheap, reliable and clean electricity.

Key policy insights

• The effect of heat stress on labour productivity is a key economic impact of climate change, which could affect national output and workers’ income.

• Effective adaptation options exist, such as shifting working hours and cool roofs, but they require policy intervention and forward planning.

• Strategic interventions, such as climate-smart municipal design, are as important as reactive or project-level adaptations.

• Adaptation solutions to heat stress are highly context specific and need to be assessed accordingly. For example, shifting working hours could be an effective way of reducing the effect of peak temperatures, but only if there is sufficient flexibility in working patterns.

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An ensemble forecast of the South China Sea monsoon     

T. N. Krishnamurti  Mukul Tewari  Ed Bensman  Wei Han  Zhan Zhang  William K. M. Lau 《大气科学进展》1999,16(2):159-182

1.IntroductionThispaperexploresanensembleforecaststrategyforthelarge--scaletropicalpredictionproblem.Thisisgeneralizedfromarecentstudyontheuseofempiricalorthogonalfunction(EOF)--basedperturbationsforhurricanetrackensembleforecasts,(ZhangandKrishnamur...  相似文献