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21.
This paper examines constraints and enabling factors towards ‘integration’ as they are perceived by actors involved in an ongoing strategy development process. The paper examines stakeholder perspectives on current progress in coastal flood risk management in London and the Thames Estuary. The case-study suggests that important steps have been taken towards an integrated and adaptive strategy development process, particularly through the development of informal stakeholder networks. However, constraints in enabling learning within the strategy development process mean that practical pathways of integration in such a large, global-scale city remain challenging to identify and perhaps even more so to implement. 相似文献
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Common bivalve larvae from New Zealand: Leptonacea 总被引:1,自引:1,他引:0
J. D. Booth 《新西兰海洋与淡水研究杂志》2013,47(2):241-254
The late stage larvae of three erycinid bivalves (Mollusca: Pelecypoda: Leptonacea) taken from the brood chamber of the adult are described (Kellia cycladiformis, Lasaea rubra hinemoa, and L. maoria), and the provisionally identified late stage larva of the erycinid Arthritica bijurca taken from the plankton is described. Also, the D‐shaped larvae of the erycinid bivalves Kellia cycladiformis, Borniola reniformis, Arlhritica crassijormis, and A. bifurca taken from the parent brood chamber are described. The seasonal occurrence of each late stage larva in the plankton at the Bay of Islands (35° 15'S, 174° 10'E), Wellington Harbour (41° 16'S, 174° 51'E), and Raumati Beach (40° 56'S, 174° 58'E), New Zealand is described. Aspects of the reproductive cycles of Lasaea rubra hinemoa and Arthritica bifurca are presented. 相似文献
24.
James M. Murphy Ben B. B. Booth Chris A. Boulton Robin T. Clark Glen R. Harris Jason A. Lowe David M. H. Sexton 《Climate Dynamics》2014,43(9-10):2855-2885
We describe results from a 57-member ensemble of transient climate change simulations, featuring simultaneous perturbations to 54 parameters in the atmosphere, ocean, sulphur cycle and terrestrial ecosystem components of an earth system model (ESM). These emissions-driven simulations are compared against the CMIP3 multi-model ensemble of physical climate system models, used extensively to inform previous assessments of regional climate change, and also against emissions-driven simulations from ESMs contributed to the CMIP5 archive. Members of our earth system perturbed parameter ensemble (ESPPE) are competitive with CMIP3 and CMIP5 models in their simulations of historical climate. In particular, they perform reasonably well in comparison with HadGEM2-ES, a more sophisticated and expensive earth system model contributed to CMIP5. The ESPPE therefore provides a computationally cost-effective tool to explore interactions between earth system processes. In response to a non-intervention emissions scenario, the ESPPE simulates distributions of future regional temperature change characterised by wide ranges, and warm shifts, compared to those of CMIP3 models. These differences partly reflect the uncertain influence of global carbon cycle feedbacks in the ESPPE. In addition, the regional effects of interactions between different earth system feedbacks, particularly involving physical and ecosystem processes, shift and widen the ESPPE spread in normalised patterns of surface temperature and precipitation change in many regions. Significant differences from CMIP3 also arise from the use of parametric perturbations (rather than a multimodel ensemble) to represent model uncertainties, and this is also the case when ESPPE results are compared against parallel emissions-driven simulations from CMIP5 ESMs. When driven by an aggressive mitigation scenario, the ESPPE and HadGEM2-ES reveal significant but uncertain impacts in limiting temperature increases during the second half of the twenty-first century. Emissions-driven simulations create scope for development of errors in properties that were previously prescribed in coupled ocean–atmosphere models, such as historical CO2 concentrations and vegetation distributions. In this context, historical intra-ensemble variations in the airborne fraction of CO2 emissions, and in summer soil moisture in northern hemisphere continental regions, are shown to be potentially useful constraints, subject to uncertainties in the relevant observations. Our results suggest that future climate-related risks can be assessed more comprehensively by updating projection methodologies to support formal combination of emissions-driven perturbed parameter and multi-model earth system model simulations with suitable observational constraints. This would provide scenarios underpinned by a more complete representation of the chain of uncertainties from anthropogenic emissions to future climate outcomes. 相似文献
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Summary. Particle-motion plots of shear waves have been studied for the section FG of the FENNOLORA seismic experiment. Shear-wave splitting is observed on some records and the polarization of the first arriving shear waves show two peaks at about N35°W and N65°E. These results can be interpreted as being due to crack-induced anisotropy with the crack direction dominated by a (dominant) horizontal stress around N35°W. This is consistent with in situ stress measurements and focal mechanism studies in Scandinavia. the results show that seismic refraction experiments may be useful in providing evidence of crack-induced anisotropy in the stable continental crust. 相似文献
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Andrei M. Sobolev Edmund C. Sutton Dinah M. Cragg Peter D. Godfrey 《Astrophysics and Space Science》2005,295(1-2):189-196
In studies of the environment of massive young stellar objects, recent progress in both observations and theory allows a unified treatment of data for maser and quasi-thermal lines. Interferometric maser images provide information on the distribution and kinematics of masing gas on small spatial scales. Observations of multiple masing transitions provide constraints on the physical parameters.Interferometric data on quasi-thermal molecular lines permits an investigation of the overall distribution and kinematics of the molecular gas in the vicinity of young stellar objects, including those which are deeply embedded. Using multiple transitions of different molecules, one can obtain good constraints on the physical and chemical parameters. Combining these data enables the construction of unified models, which take into account spatial scales differing by orders of magnitude.Here, we present such a combined analysis of the environment around the ultracompact HII region in W3(OH). This includes the structure of the methanol masing region, physical structure of the near vicinity of W3(OH), detection of new masers in the large-scale shock front and embedded sources in the vicinity of the TW young stellar object. 相似文献
30.
Geochemical prospecting for baryte and celestite using a portable radioisotope fluorescence analyser
T.K. Ball S.J. Booth E.F.P. Nickless R.T. Smith 《Journal of Geochemical Exploration》1979,11(3):277-284
A method is described for determining the Ba and Sr content of soils in the field laboratory using a portable, isotope source, X-ray fluorescence analyser. The application of these techniques to the exploration for vein-type barytes and stratiform celestite deposits in the west of England is described. Satisfactory accuracy is achieved in comparison with other methods, along with considerable economies in time and effort. Detection limits (2 × standard deviation) are 200–300 ppm for Ba and about 500 ppm for Sr. 相似文献