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91.
Neil Gunningham 《Climate Policy》2013,13(2):302-320
The question of whether China is on the verge of a ‘shale gas revolution’ is examined. This has potentially significant consequences for energy policy and climate change mitigation. Contrary to the optimistic reading of some commentators, it argues that various technological, environmental, political, regulatory and institutional factors will constrain the growth of China's shale gas market and that such a revolution might in any event have consequences that are at best mixed, at worst antithetical to climate change mitigation.Policy relevanceChina's reserves of unconventional gas have the potential to transform energy policy, as has occurred in the US, resulting in the substitution of shale gas for coal in the energy mix. Because gas emits only approximately half the GHG per unit as coal, such a move would have important implications for climate policy. However, substantial obstacles stand in the way of the ‘energy revolution’ that some policy analysts see China as embarking upon. The need to acknowledge these obstacles, particularly those relating to regulation and governance (and whether or to what extent they can be overcome), is an issue of profound importance to the future of climate and energy policy. 相似文献
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93.
Neil Dello Russo Michael J. Mumma Karen Magee-Sauer Boncho P. Bonev I.S. McLean 《Icarus》2006,184(1):255-276
We obtained high-resolution (λ/Δλ∼25,000) spectra of Comet C/1999 H1 (Lee) on UT 1999 August 19.6 and 21.6 using the cross-dispersed Near InfraRed SPECtrometer (NIRSPEC) at the Keck Observatory atop Mauna Kea, HI. Here we present spectra of Comet Lee between 2.874 and 3.701 μm (3479-2702 cm−1) representing the most complete high-resolution infrared survey of a comet to date in this wavelength region. Using published line lists and laboratory spectra we have identified 444 of the 545 distinct emission features present in these spectra. We have tabulated the rest frequencies, assignments, relative intensities, and signal-to-noise ratios of all detected emissions. In addition to gaining insights into the chemistry of Comet Lee, this survey provides a valuable tool for planning future high-resolution infrared observations of comets and other astronomical targets, and for retrospective comparison to existing high-resolution infrared datasets. 相似文献
94.
Roger W. Stump 《The Professional geographer》1987,39(4):438-449
This study examines the hypothesis that the determinants of denominational switching vary regionally among white American Protestants. Data for the analysis are taken from the National Opinion Research Center's General Social Survey for 1974 through 1984. Using logistic regression, the analysis compares the determinants of switching among respondents residing in the nine Census regions of the U.S. Results reveal significant regional differences in the determinants of switching, especially in the effects of conversion, childhood affiliation and interdenominational marriage. 相似文献
95.
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97.
The dates of recession of eleven outlet glaciers of the Hielo Patagónico Norte (Northern Patagonian Icefield) from their recent maximum positions have been inferred from dendrochronology, lichenometry, radiocarbon dating and historical sources. We have refined the dating for part of the Little Ice Age period in this area placing a glacial advance to between AD 1650 and 1766 with the latter date favoured as conformable with historical records and an uncalibrated radiocarbon determination. Glacier recession from maximal positions began in the early 1860s–1870s. Recession was largely synchronous on the western and eastern sides of the Icefield. This synchronicity suggests that climate forcing over-rides second-order controls on glacier behaviour such as the nature of the terminal environment (e.g. calving/non-calving) or differences in glacier drainage basin area. We argue that this icefield-wide glacier recession represents a response to post-Little Ice Age warming, and provides further evidence for the global extent and near synchronous termination of the Little Ice Age. 相似文献
98.
Summary. The frozen flux approximation of Roberts & Scott is a constraint on the core field that can be used to aid interpretation of the very sparse datasets that palaeomagnetism and archaeomagnetism provide. It gives bounds on the size of the components of the magnetic field at a point, of the Gauss coefficients, and, if valid over such long time periods, limits the shape of the field during transitions between normal and reversed polarities. The maximum intensity at a point, consistent with the present flux, is 281 μT or 4 times the maximum field observed today. The present dipole is about 50 per cent of its upper bound. Polarity reversal is impossible if the transition field is purely axisymmetric. None of the measurements we consider violate the frozen flux approximation. 相似文献
99.
Neil Kennan 《The Australian geographer》1988,19(2):284-289
The implementation of an ‘appropriate’ housing subdivision in Lae, Papua New Guinea represents a new approach in creating an acceptable environment for the urban poor. The unique hexagonal design of the Tensiti development and its aims and policy implications are discussed. It appears that at least some of the urban poor of Lae now live in a settlement which satisfies the demands of town planners, urban administrators and the realities of the settlers' basic needs and resources. 相似文献
100.