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11.
Here we reconstruct the last advance to maximum limits and retreat of the Irish Sea Glacier (ISG), the only land-terminating ice lobe of the western British Irish Ice Sheet. A series of reverse bedrock slopes rendered proglacial lakes endemic, forming time-transgressive moraine- and bedrock-dammed basins that evolved with ice marginal retreat. Combining, for the first time on glacial sediments, optically stimulated luminescence (OSL) bleaching profiles for cobbles with single grain and small aliquot OSL measurements on sands, has produced a coherent chronology from these heterogeneously bleached samples. This chronology constrains what is globally an early build-up of ice during late Marine Isotope Stage 3 and Greenland Stadial (GS) 5, with ice margins reaching south Lancashire by 30 ± 1.2 ka, followed by a 120-km advance at 28.3 ± 1.4 ka reaching its 26.5 ± 1.1 ka maximum extent during GS-3. Early retreat during GS-3 reflects piracy of ice sources shared with the Irish-Sea Ice Stream (ISIS), starving the ISG. With ISG retreat, an opportunistic readvance of Welsh ice during GS-2 rode over the ISG moraines occupying the space vacated, with ice margins oscillating within a substantial glacial over-deepening. Our geomorphological chronosequence shows a glacial system forced by climate but mediated by piracy of ice sources shared with the ISIS, changing flow regimes and fronting environments.  相似文献   
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This paper describes an adaptation of the ‘leap-frog’ method of barometric altimetry which enables altimetric surveys to be undertaken by a single operator using a single barometer with no requirement for base stations. The method involves two readings at each station, the first bracketed by readings at the previous station, and the second bracketed by readings at the subsequent station. Linear interpolation is used to estimate what the readings would have been at each station at the time that readings were taken at the adjacent stations. Under suitable meteorological conditions errors are generally less than ±1 m, which is sufficiently accurate for a wide variety of geomorphological applications. The method has significant advantages in terms of cost and/or time over more accurate methods such as electronic distance measurement surveys or survey quality global positioning systems. The paper is accompanied by a Microsoft Excel template spreadsheet, BAROSURV.XLT, which converts temperature and pressure readings to relative elevations, and graphs the results. Notes on the use of BAROSURV.XLT are included in the ASCII text file BAROSURV.NOT.  相似文献   
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Geoff Kelly 《Geoforum》2007,38(2):326-338
The development of renewable energy sources is of prime interest to many countries seeking to pursue greenhouse gas emission reduction obligations. The increased use of renewables offers the possibility of not only contributing to emission reduction, but at the same time improving energy supply diversity and security, and developing employment and business in related supply industries. Two main mechanisms are in common use, one a quota (quantity) instrument often associated with tradable certificates, and the other a prescribed pricing mechanism. This paper considers the renewable energy development strategies of three countries (the UK, Australia, and New Zealand) all using a variant of the quota/certificate approach as the central instrument in their programs. The regulatory frameworks defining the application of the certificate systems differ notably, and the likely differing outcomes suggest that these regulatory settings may be at least as important as the selection of the basic policy instrument, in determining the overall success of programs of this nature.  相似文献   
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Independence,dependence and fragmentation in the South Pacific   总被引:1,自引:0,他引:1  
J. Connell Dr. 《GeoJournal》1981,5(6):583-588
Since the 1960s most island groups of the South Pacific have achieved independence and many new nations have been established; only the very smallest islands remain colonies. Most of the small nations are extremely small yet secession movements in many areas have resulted in fragmentation producing the break-up of the Gilbert and Ellice Islands and the disintegration of the Trust Territory of the Pacific Islands. This has emphasized the distinctive characteristics of the Pacific nations: their small size (in population and in area) and limited natural resources, their isolation from each other and from markets and fragmentation within multiple island countries. The extension of outside interests into the Pacific has brought rapid economic changes, the emergence of cash cropping and the decline of subsistence agriculture, increased dependence on imports (especially food, resulting in some nutritional problems) and rapid urbanization, producing growing dependence and inequality which regional ties between the Pacific nations have not been able to overcome. Outmigration from the smallest nations to USA and New Zealand is likely to be maintained and the unusual characteristics of these small island nations suggest that strategies of development that appear viable elsewhere have little chance of success in the Pacific.  相似文献   
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