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1.
Climate change is likely to adversely affect many countries throughout the world, but the responses of different countries to this threat vary widely. Attempts to explain the differences in countries’ mitigative policies have been largely deficient. This study seeks to assess the degree to which vulnerability may improve the level of explanation of adopted mitigation policies, studying over 90 countries between 1990 and 2011. Vulnerability is defined to be comprised of two basic factors: impacts (expected damages due to climate change) and adaptive capacity (the ability to adjust to these damages). As there may be a gap between declared and implemented policies, these components of mitigation policy are examined separately. In addition, other variables which mediate between these ‘extreme ends’ of mitigation policies are tested.The effect of vulnerability on climate change mitigation policies is examined by multiple regressions, incorporating a wide range of control variables. The results indicate that climate impacts do not affect mitigation policies. Adaptive capacity has a positive effect on the level of declared policy, but this effect becomes insignificant once implemented policy is examined. However, other tests suggest a possible transition from declarations to actions by high adaptive capacity countries. This finding suggests that high adaptive capacity countries do not view mitigation and adaptation as substitutes. Further analyses indicate that the insignificancy of impacts is caused by the uncertainty in their assessment. 相似文献
2.
Morphometry and distribution of isolated caves as a guide for phreatic and confined paleohydrological conditions 总被引：1，自引：0，他引：1
Isolated caves are a special cave type common in most karst terrains, formed by prolonged slow water flow where aggressivity is locally boosted. The morphometry and distribution of isolated caves are used here to reconstruct the paleohydrology of a karstic mountain range. Within a homogenous karstic rock sequence, two main types of isolated caves are distinguished, and each is associated with a special hydrogeologic setting: maze caves form by rising water in the confined zone of the aquifer, under the Mt. Scopus Group (Israel) confinement, while chamber caves are formed in phreatic conditions, apparently by lateral flow mixing with a vadose input from above. 相似文献
3.
Shmuel M. Rubinstein Itay Barel Ze’ev Reches Oleg M. Braun Michael Urbakh Jay Fineberg 《Pure and Applied Geophysics》2011,168(12):2151-2166
Faults are intrinsically heterogeneous with common occurrences of jogs, edges and steps. We therefore explore experimentally
and theoretically how fault edges may affect earthquake and slip dynamics. In the presented experiments and accompanying theoretical
model, shear loads are applied to the edge of one of two flat blocks in frictional contact that form a fault analog. We show
that slip occurs via a sequence of rapid rupture events that initiate from the loading edge and are arrested after propagating
a finite distance. Each successive event extends the slip size, transfers the applied shear across the block, and causes progressively
larger changes of the contact area along the contact surface. Resulting from this sequence of events, a hard asperity is dynamically
formed near the loaded edge. The contact area beyond this asperity is largely reduced. These sequences of rapid events culminate
in slow slip events that precede a major, unarrested slip event along the entire contact surface. We suggest that the 1998
M5.0 Sendai and 1995 off-Etorofu earthquake sequences may correspond to this scenario. Our work demonstrates, qualitatively,
how the simplest deviation from uniform shear loading may significantly affect both earthquake nucleation processes and how
fault complexity develops. 相似文献
4.
Institutional conditions for IWRM: the Israeli case 总被引：3，自引：1，他引：2
Fischhendler I 《Ground water》2008,46(1):91-102
Many places in the world are experiencing a water crisis. This water crisis is attributed to a governance crisis, whereas often fragmented institutional and physical water structures are used to explain a policy of overexploitation. The Israeli water system, which adopted integrated water resource management (IWRM), is often cited as a model for other countries struggling with fragmented water systems. Yet, despite the exceptional degree of integration, Israel in the past two decades has adopted an unsustainable water policy. The aim of this study is to understand this failure and thereby to postulate on the institutional conditions required for successful implementation of IWRM. The study focuses on the politics of water allocation during the drought of 1999 to 2002. It was found that the failure originates in setting administrative divisions in the decision-making process and in differential checks, with no balances implicitly instituted within the integrated water system. These two factors have resulted in a water system that is physically integrated but is not coupled by a balanced institutional structure. This case study teaches us that when reforming the water sector along IWRM lines, measures must be taken to ensure that the physical integration coincides with a balanced institutional integration-otherwise the results may be worse than if there were no integration at all. 相似文献
5.
Gypsum precipitation kinetics were examined from a wide range of chemical compositions , ionic strengths (4.75-10 m) and saturation state with respect to gypsum (1.16-1.74) in seeded batch experiments of mixtures of Ca2+-rich Dead Sea brine and -rich seawater. Despite the variability in the experimental solutions, a single general rate law was formulated to describe the heterogeneous precipitation rate of gypsum from these mixtures:
6.
ABSTRACTThe literature on environmental security often stresses the complementarity between sustainability and broader security goals. Less emphasis has been placed on possible trade-offs between security objectives and aspects of sustainability. This study examines the conditions under which these synergies and trade-offs are likely to occur, and how the trade-offs can be reconciled, especially during times of peacebuilding. As a case study, we analyse the effect of Israeli security concerns on environmental infrastructure designed to treat wastewater in the West Bank. This study identifies several sustainability–security trade-offs: (1) economic—in which security concerns raise costs of wastewater infrastructure, thereby crowding-out other potentially productive investments; (2) equity—in which security concerns result in disproportionate exposure of populations to environmental hazards; and (3) environmental—in which security concerns increase ecological footprints. Yet, our case study also indicates that both sides used a variety of creative measures to reconcile these trade-offs.
EDITOR D. Koutsoyiannis GUEST EDITOR K. Aggestam 相似文献
7.
The role of uncertainties in the design of international water treaties: an historical perspective 总被引：1，自引：1，他引：0
Water is one natural resource whose management is especially susceptible to uncertainties, many of which are being exasperated by climate change. Some of these uncertainties originate from knowledge deficits in physical conditions while others relate to behavioral and social variability related to water supply and use. However, to our knowledge no quantitative analysis of how uncertainties have been translated into transboundary water treaty structures exists. The present paper partially fills this gap through an examination of how uncertainty has been reflected in basin specific transboundary treaties and how that reflection has changed over the last century. While we could identify only minor trends in the frequency with which uncertainties are mentioned in treaties, we did find two clear patterns in the strategies adopted to deal with them. First, treaties seem to adopt a portfolio approach that spreads the dangers of uncertainty by concurrently including several management strategies simultaneously. Second, there is a trend towards more open-ended strategies in recent decades, rather than hard codification of rules as had earlier been more common. 相似文献
8.
The Sr/Ca of aragonitic coral skeletons is a commonly used palaeothermometer. However skeletal Sr/Ca is typically dominated by weekly-monthly oscillations which do not reflect temperature or seawater composition and the origins of which are currently unknown. To test the impact of transcellular Ca2+ transport processes on skeletal Sr/Ca, colonies of the branching coral, Pocillopora damicornis, were cultured in the presence of inhibitors of Ca-ATPase (ruthenium red) and Ca channels (verapamil hydrochloride). The photosynthesis, respiration and calcification rates of the colonies were monitored throughout the experiment. The skeleton deposited in the presence of the inhibitors was identified (by 42Ca spike) and analysed for Sr/Ca and Mg/Ca by secondary ion mass spectrometry. The Sr/Ca of the aragonite deposited in the presence of either of the inhibitors was not significantly different from that of the solvent (dimethyl sulfoxide) control, although the coral calcification rate was reduced by up to 66% and 73% in the ruthenium red and verapamil treatments, respectively. The typical precision (95% confidence limits) of mean Sr/Ca determinations within any treatment was <±1% and differences in skeletal Sr/Ca between treatments were correspondingly small. Either Ca-ATPase and Ca channels transport Sr2+ and Ca2+ in virtually the same ratio in which they are present in seawater or transcellular processes contribute little Ca2+ to the skeleton and most Ca is derived from seawater transported directly to the calcification site. Variations in the activities of Ca-ATPase and Ca-channels are not responsible for the weekly-monthly Sr/Ca oscillations observed in skeletal chronologies, assuming that the specificities of Ca transcellular transport processes are similar between coral genera. 相似文献
9.
Conflict resolution mechanisms are recognised as indispensable constituting elements of transboundary water agreements. Earlier studies confirm, however, that such mechanisms are either incomplete, unsophisticated or absent from treaties. We argue that transaction costs, which occur during treaty negotiation, may constitute a barrier to the adoption of conflict resolution mechanisms in water treaties. Transaction costs are never equal and depend largely on the context in which negotiations take place. A content analysis of the treaties in the Transboundary Freshwater Dispute Database demonstrates that the adoption of conflict resolution mechanisms to transboundary water treaties is not random, but may be affected by external factors that influence the transaction cost of negotiating such mechanisms. Water scarcity and a history of cooperative hydro-relations are factors that coincide with the presence of conflict resolution mechanisms in treaties and are therefore considered to lower transaction costs. External resource dependency is believed to stir transaction costs to such an extent that it prevents the adoption of mature mechanisms. The same goes for political freedom, political heterogeneity and the presence of colonial signatories as these factors correlate with mechanism absence and the adoption of a low number of conflict resolution mechanisms per treaty. The effect of hydrological variability resulted insignificant, indicating that variability remains largely ignored by negotiators of transboundary water treaties. Our research further shows that if a mechanism for conflict resolution contains one element of maturity (e.g. institutionalisation or an activation procedure based on a unilateral rule) other elements of maturity are also likely to be present, providing negotiators with an incentive to negotiate conflict resolution mechanisms with at least one mature characteristic. Finally, the adoption of a high number of mechanisms coincides with the presence of institutionalised forms for conflict resolution, supporting the incentive of negotiating more than two mechanisms per treaty. 相似文献
10.
The Dead Sea brine is supersaturated with respect to gypsum (Ω = 1.42). Laboratory experiments and evaluation of historical data show that gypsum nucleation and crystal growth kinetics from Dead Sea brine are both slower in comparison with solutions at a similar degree of supersaturation. The slow kinetics of gypsum precipitation in the Dead Sea brine is mainly attributed to the low solubility of gypsum which is due to the high Ca2+/SO42− molar ratio (115), high salinity (∼280 g/kg) and to Na+ inhibition.Experiments with various clay minerals (montmorillonite, kaolinite) indicate that these minerals do not serve as crystallization seeds. In contrast, calcite and aragonite which contain traces of gypsum impurities do prompt precipitation of gypsum but at a considerable slower rate than with pure gypsum. This implies that transportation inflow of clay minerals, calcite and local crystallization of minerals in the Dead Sea does not prompt significant heterogeneous precipitation of gypsum. Based on historical analyses of the Dead Sea, it is shown that over the last decades, as inflows to the lake decreased and its salinity increased, gypsum continuously precipitated from the brine. The increasing salinity and Ca2+/SO42− ratio, which results from the precipitation of gypsum, lead to even slower kinetics of nucleation and crystal growth, which resulted in an increasing degree of supersaturation with respect to gypsum. Therefore, we predict that as the salinity of the Dead Sea brine continues to increase (accompanied by Dead Sea water level decline), although gypsum will continuously precipitate, the degree of supersaturation will increase furthermore due to progressively slower kinetics. 相似文献