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61.
The direction of UK energy policy requires a renewed impetus if the goal of climate change stabilization is to be met. Cost is not the main issue: a transformation to a low-carbon energy system may be no more expensive than meeting future energy demands with fossil fuels. Institutional barriers are preventing the large-scale adoption of the necessary technologies. New institutions to promote low-carbon technologies have not yet led to investment on the necessary scale. Further changes to the operation of the UK electricity markets to create a ‘level playing field’ for small-scale and intermittent generation are necessary. UK policy can contribute to international agreements following on from the Kyoto Accord, which also need to address the institutional barriers to energy technology development and transfer.  相似文献   
62.
《水文科学杂志》2013,58(5):992-1003
Abstract

The extreme Tyne (Northumbria, UK) flood in January 2005 provided the opportunity to reassess flood risk and to link peak discharge and flooded area to probability of occurrence. However, in spite of the UK guidance on flood risk assessment given in the Flood Estimation Handbook (FEH), there is still considerable subjectivity in deriving risk estimates. A particular problem for the Tyne arises from the effects of river bed gravel extraction both on the reliability of gauged discharges and in the interpretation of historical level data. In addition, attenuation and drawdown of Kielder Water has reduced downstream flood risk since 1982. Estimates from single-site, pooled estimates and historical information are compared. It is concluded that the return period of the observed flood was around 71 years on the lower Tyne and was probably the largest flood since 1815.  相似文献   
63.
Windy pits are open fissures within the Corallian strata of the North York Moors. Here we present nine thermal ionization mass spectrometry (TIMS) U–Th dates on speleothem from the windy pits, the first radiometric dates on calcite for these features and for this region. The dates cluster within three time periods: the interglacial peaks of marine isotope stage (MIS) 7 (~208 to ~190 ka), MIS 5 (~127 ka to ~109 ka) and the Holocene, correlating with the marine isotope record and with the broad pattern of interglacial calcite deposition observed for northern England. However, of the two high‐resolution studies available for comparison, the windy‐pit dates match only the Lancaster Hole dates. The location of the windy pits outside of the Devensian ice limits, within the ice‐free but periglaciated region, suggests that the region has remained ice‐free since some time before MIS 7. The prevalence of widespread and prolonged permafrost conditions suggests a plausible mechanism for these open rift caves in slope‐side periglacial mass movement. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
64.
The sources and sinks of manganese in underground coal mine workings are poorly understood compared to those of iron. The geochemical system in the secondary egress drift of Caphouse Colliery near Horbury, UK, is an ideal system for studying these processes. Five locations along the drift and four secondary inflows to the drift were sampled 24 times through the year commencing May 2005. During the sampling period, the pH in the main channel varied from 6.73 to 7.93 and increased along the flow path. The secondary inflows to the drift from the strata were of higher alkalinity (mean = 385 mg/L as CaCO3) than the main flow (mean = 330 mg/L as CaCO3); the affects of mixing between the less alkaline main channel and the more alkaline secondary inflows and of carbon dioxide exsolution are evident in the form of carbonate and hydroxide precipitates. SEM and XRD analysis of precipitates collected from the drift confirm the presence of calcium and manganese carbonates and ferric hydroxide. PHREEQC speciation and solubility modelling confirms supersaturation of the water in the main channel with respect to ferric oxy-hydroxides; iron, manganese, magnesium and calcium carbonates; and manganese oxides. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
65.
Fish populations in estuaries are often monitored with traditional sampling gears such as trawls. Trawling is relatively expensive and may be hindered by environmental conditions such as tides and substrates. Power station cooling-water intake screens have been effectively used as estuarine fish sampling devices for many years, but very few quantitative comparisons of intake fish-catch characteristics with samples from other collection methods have been made. Fish collected at the cooling-water intake of a large power station in the lower Forth estuary, UK, were more similar in assemblage composition to fish caught by nearby pelagic trawling than to fish caught by Agassiz (demersal) trawling, mostly because the intake and pelagic-trawl catches were largely composed of clupeids (Sprattus sprattus and Clupea harengus). The intake catch was typified by pelagic, demersal, and benthic species, however, and was less variable than the catches made by the two trawls. Monthly trends in relative abundance correlated reasonably well between the intake and trawl samples. Fish collected at the intake tended to be significantly smaller than those collected by trawling, which was probably attributable to the intake's smaller mesh size. The study highlighted the utility of a cooling-water intake as an efficient, low-cost fish sampling device, which should be considered as an alternative to trawling as the cost of the latter increases into the future.  相似文献   
66.
英国温室气体排放贸易制度的实践与评价   总被引:1,自引:0,他引:1  
温室气体排放贸易作为一种经济激励型的环境管理手段,对企业减少温室气体排放有成本效率作用。详细介绍了英国温室气体排放贸易制度框架,并对其政策的效果及存在的问题进行了评价。  相似文献   
67.
从2003年的《能源白皮书--构建一个低碳社会》到2007年的《能源白皮书--迎接能源挑战》,英国的气候变化政策发生了微妙变化,从强调自身减排蜕变到一再强调国际行动以及建立相应国际框架的重要性和必要性。其中的原因有3方面:1) 英国的温室气体尤其是CO2 排放由于各种原因出现反弹迹象,减排前景不明朗;2) 英国能源供应的对外依存度越来越高,出于对能源供应安全的考虑;3) 担心发展中国家的温室气体排放势头抵消其减排努力。可见,在能源政策方面,英国变得更加务实。  相似文献   
68.
A foraminiferal transfer function for mean tide level (MTL) is used in combination with AMS radiocarbon dated material to construct a record of relative sea‐level (RSL) change from Poole Harbour, southern Britain. These new data, based on multiple cores from duplicate sites, indicate four phases of change during the last 5000 cal. (calendar) yr: (i) rising RSL between ca. 4700 cal. yr BP and ca. 2400 cal. yr BP; (ii) stable to falling RSL from ca. 2400 cal. yr BP until ca. 1200 cal. yr BP; (iii) a brief rise in RSL from ca. 1200 cal. yr BP to ca. 900 cal. yr BP, followed by a period of stability; (iv) a recent increase in the rate of RSL rise from ca. 400–200 cal. yr BP until the present day. In addition, they suggest that the region has experienced long‐term crustal subsidence at a rate of 0.5 mm C14 yr?1. Although this can account for the overall rise in MTL observed during the past 2500 yr, it fails to explain the changes in the rate of rise during this period. This implies that the phases of RSL change recorded in the marshes of Poole Harbour reflect tidal range variations or ‘eustatic’ fluctuations in sea‐level. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
69.
The earliest attempts to find oil in Britain, dating from 1918–1922, based on anticlines flanking the Pennines, were largely unsuccessful. Renewal of exploration in the 1930s, aimed at a broader range of prospects, met with much criticism but went ahead after nationalization of the unknown and undiscovered oil resources (1934). The south of England ranked as first priority but the initial drilling of the new campaign carried out in 1935–1937 yielded only minor quantities of oil and gas. Attention was transferred in 1938 to Upper Palaeozoic prospects in the Midlands and north, resulting in small gas and oil discoveries in Scotland and Yorkshire, and discovery of a series of commerical oilfields in the Upper Carboniferous of Nottinghamshire. In the 1950s the first commercial discovery in the Jurassic was made at Kimmeridge in Dorset. Further Carboniferous discoveries were made in Nottinghamshire and Lincolnshire, and a series of fresh objectives defined by seismic reflection were drilled in the Mesozoic basin of southern England. This phase of exploration was terminated at the end of 1964 by adverse fiscal changes. Continuation of effective exploration operations remained uneconomic until the oil price rise in 1973.  相似文献   
70.
Detailed stratigraphic, palaeobotanical (diatom and pollen) and radiometric evidence from a sequence of buried estuarine deposits, buried peat and overlying estuarine ‘carse’ deposits at Wester Rhynd, in Lower Strathearn, suggests the occurrence of two brief marine incursions between the abandonment by the sea of a buried estuarine flat, probably the Low Buried Beach, at about 8765 ± 75 BP, and c. 8500 BP. The first incursion, shortly after 8565 ± 85 BP, caused bottom-living marine diatoms to be thrown without clastic material onto the rapidly accumulating terrestrial peat. The second, bracketed by dates of 8485 ± 80 and 8510 ± 85 BP, deposited an extremely thin (1 mm) layer of fine sand that interrupts an otherwise unbroken buried peat succession covering the period 8765 ± 75 to 7710 ± 70 BP. The marine diatom, lithostratigraphic and 14C evidence together are consistent with a storm, storm-surge or tsunami origin for these events, which are recognised principally from the diatom evidence, having left no mark in the pollen record.  相似文献   
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