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31.
Tristan Sturm  Eric Oh 《Geoforum》2010,41(1):154-163
The aftermath of Hurricane Katrina has piqued interest in the insurance industry, and this scrutiny has led to assumptions that the industry has become unstable and unprofitable with the increased incidence of disasters in highly-insured regions of the world. This paper challenges that assumption by arguing that the insurance industry has responded by spreading risk through scaled and networked recovery schemes. We found that because of competitive strategies of risk-spreading and displacement arrangements, the industry has actually profited as a whole. Regional insurance companies have always relied on the higher financial scales of the reinsurance industry in Munich, Zurich, and London. But with claims reaching into the billions of dollars, the reinsurance industry itself has raised premiums, spread risk farther afield, and jumped scale by spreading risk to futures markets called Alternative Risk Transfers (ARTs). However, the recession beginning in 2008 has called into question the viability of using futures markets as insurance. It is shown through a media analysis of four major business publications (The Economist, The New York Times, The Financial Times and The Wall Street Journal) how the industry responded to the costs of the 2004, 2005, and 2006 hurricane seasons. Because geography is rather new to this literature, this paper also offers a broad review of the insurance industry.  相似文献   
32.
Increasing attention by consumers to the social and environmental dimensions of the food they eat has generated many different responses, including certification programs, watch lists and local/slow food movements. This article examines the more recent entry of seafood into these consumer social movements. Although a concern with the family farm—as well as tendency to equate national security with food security—has long connected terrestrial food production with other cultural concerns, fisheries have tended to be regarded more as natural resources. Considering seafood as part of the “food system” would enhance the management of fisheries, while the long engagement in fisheries with co- and adaptive management and the politics of knowledge would enrich the debate in the agri-foods literature. The article also offers suggestions on how fisheries management could better govern for sustainable food systems, and provides further ideas about food, sustainability and governance.  相似文献   
33.
运用SI-Harris算子提取遥感图像点特征   总被引:1,自引:0,他引:1  
推导了SI-Harris算子(尺度不变Harris算子)的理论公式,并将其应用于遥感图像的点特征提取。重点对Harris算子与SI-Harris算子在不同空间分辨率遥感图像上的点特征提取进行实验比较,利用"重复率"指标对实验结果进行定量评价。实验表明:SI-Harris算子"重复率"较Harris算子有明显提升,可用于不同空间分辨率遥感图像的点特征提取,进而可服务于不同空间分辨率遥感图像的匹配。  相似文献   
34.
The rhetorical zeal for green enterprise as a global fix for the tripartite challenges of economic recession, environmental degradation and social inequality is increasingly visible in state and non-state pronouncements around the globe under the banner of ‘The Green Economy’. In particular, many policy-facing statements call for transitions leading to a transformation in development practices. Yet there is little detail either in policy or research regarding the types of transitions needed and how they are to be initiated, nor agreement about what a transformed economy might look like. Despite this, there are emergent activities within the cleantech arena which are being heralded as actually existing examples of green economy activities. One means through which these activities are seeking to exert influence over development trajectories is by clustering both at the subnational and transnational level. While diverse in formation, many of these clusters are hybridised, involving actors from public, private and civil society sectors. Critiquing the efficacy of mainstream industrial cluster theory to analyse hybridised cleantech clustering, this paper presents a unique synthesis of current thought on multiscalar environmental governance and socio-spatial formations to explore the practices and potentialities of these hybridised cleantech clusters. Surveying the landscape of cleantech clustering and meta-clustering, before focusing in depth on one case study, the contribution of clustering to transitioning towards a transformed green economy is considered. Despite strong forces, both within and beyond cleantech clusters, for maintaining neoliberalised approaches to cleantech activity, it is concluded that for as long as cleantech clusters remain open and inclusive of actors proposing alternative pathways they do represent potential, albeit provisional, assemblages for transformation.  相似文献   
35.
东川拖布卡金矿矿化层位与找金方向   总被引:10,自引:3,他引:7  
薛步高 《云南地质》2005,24(3):243-253
超大型拖布卡金矿的发现,表明东川地区具备找金前景.“黑层”是金的成矿前提,断裂加蚀变是成矿必备条件,基性与中性岩脉在容矿层中的侵位,是找富金的重要标志.金成矿全过程应是多旋回(晋宁、华力西、燕山、喜马拉雅山)成矿作用,且受剪切破碎带控制的黑层型金矿.  相似文献   
36.
The scale factor of a superconducting gravimeter (SG) at the Esashi Earth Tides Station, Japan, was revised by repeating co-located absolute gravity measurements with an FG5 gravimeter. Although the calibration results from the absolute gravimeter (AG) show an apparent secular change in the scale factor of the SG (0.4% for the period 1993–2002), the relative scale factors, which are determined by tidal analysis with the response method, indicate that it has changed by no more than 0.01% during the above period. If the mean scale factor over the 10 years is adopted, a value of –56.082±0.029 Gal/V (1 Gal =10–8 m s–2) is obtained, which is about 0.4% smaller than that used in the global geodynamics project (GGP) database. Based on this newly determined scale factor, the tidal gravity factors at Esashi have been re-estimated. The observed tidal factors, corrected for the ocean tide effects with recent models, indicate that the theoretical gravity factors for an inelastic Earth model are more consistent with the observations than are those for an elastic model.  相似文献   
37.
《The Journal of geography》2012,111(6):258-266
Abstract

People generally do not perceive New England to be tornado-prone. Yet, there is a long history of such storms in the six states going back to the late seventeenth century. Usually, New England tornadoes are small and short-lived; even so, some have caused many deaths and much property damage. There is a greater probability for a person to be affected by a tornado in southern New England than in much of the American Midwest. As building and population density increases, so does the hazard potential. Data from awareness surveys indicate that the lack of tornado knowledge remains a serious problem for teachers, students, and the public, and government information about such storms is not being widely disseminated.  相似文献   
38.
Although tropical deforestation bears a close relationship with climate change, its exact contribution to climate warming and its threshold of exerting a noticeable influence remain unknown. This study attempts to bridge this knowledge gap by analyzing deforestation data of Heilongjiang Province, China in relation to climate data. It is found that forest cover was reduced from 238,335 km2 in 1958 to 216,009 km2 in 1980, and further to 207,629 km2 in 2000. During this period the provincial annual temperature rose by 1.68 °C, against the nation-wide warming of 0.99 °C during the same period. At the provincial level the observed deforestation caused a warming in the vicinity of 0.69 °C. This warming does not bear any definite relationship with latitude and elevation. At the local scale, deforestation is related inversely to the rise in decadal temperature in the form of ΔT = −0.013ΔF + 0.4114 (R2 = 0.30). There is a positive relationship between the accuracy (R2 value) of predicting climate warming from deforestation and its severity. The critical threshold for deforestation to exert a noticeable impact on climate warming (e.g., R2 = 50%) appears to be 5 km2. The amount of forest cover at the beginning of a period can inhibit temperature rise, but its exact effect on climate warming is difficult to quantify.  相似文献   
39.
Recently, there is increasing evidence on the interaction of atmospheric high-frequency (HF) variability with climatic low-frequency (LF) variability. In this study, we examine this relationship of HF variability with large scale circulation using idealized experiments with an aqua-planet Atmospheric GCM (with zonally uniform SST), run in different zonal momentum forcing scenarios. The effect of large scale circulation changes to the HF variability is demonstrated here. The HF atmospheric variability is enhanced over the westerly forced region, through easterly vertical shear. Our study also manifests that apart from the vertical wind shear, strong low-level convergence and horizontal zonal wind shear are also important for enhancing the HF variance. This is clearly seen in the eastern part of the forcing, where the HF activity shows relatively maximum increase, in spite of similar vertical shear over the forced regions. The possible implications for multi-scale interaction (e.g. MJO–ENSO interaction) are also discussed.  相似文献   
40.
A cluster analysis of daily outgoing longwave radiation (OLR) anomalies from 1979 to 2002 over the Southern Africa/Southwest Indian Ocean (SWIO) region for the November to February season reveals seven robust and statistically well separated recurrent patterns of large-scale organized convection. Among them are three regimes indicative of well defined tropical–temperate interactions linking the hinterland parts of Southern Africa to the mid-latitudes of the SWIO. Preferred transitions show a tendency for an eastward propagation of these systems. Analysis of daily rainfall records for South Africa shows that six of the OLR regimes are associated with spatially coherent and significant patterns of enhanced or reduced daily rainfall over the country. Atmospheric anomalies from the NCEP/DOE II reanalysis dataset show that the OLR regimes are associated with either regional or near-global adjustments of the atmospheric circulation, the three regimes representative of tropical–temperate interactions being in particular related to a well-defined wave structure encompassing the subtropical and temperate latitudes, featuring strong vertical anomalies and strong poleward export of momentum in the lee of the location of the cloud-band. The time-series of OLR regimes seasonal frequency are correlated to distinctive anomaly patterns in the global sea-surface-temperature field, among which are shown to be those corresponding to El Nino and La Nina conditions. The spatial signature of El Nino Southern Oscillation’s (ENSO) influence is related to the combination of an increased/decreased frequency of these regimes. It is shown in particular that the well-known “dipole” in convection anomalies contrasting Southern Africa and the SWIO during ENSO events arises as an effect of seasonal averaging and is therefore not valid at the synoptic scale. This study also provides a framework to better understand the observed non-linearities between ENSO and the seasonal convection and rainfall anomalies over the region.  相似文献   
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