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21.
Declan G. De Paor 《Journal of Structural Geology》1984,6(3):335-337
By combining a compass, counterweight and gimbal, an instrument for simultaneous measurement of dip, strike, pitch, plunge and trend data has been constructed. The instrument automatically locates the strike of the surface on which it is placed. It may serve as a useful teaching aid in the structural laboratory. 相似文献
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1961-2005年宁夏极端降水事件变化趋势分析 总被引：11，自引：0，他引：11
利用1961-2005年宁夏逐日降水量资料,将降水量划分为9个级别,分析了宁夏45 a来各级别降水日数的变化趋势。结果表明：年降水量以平均3.6 mm/10 a的速率减少;近15 a来,冬、春季降水量明显减少,夏、秋季10.0 mm以下降水日数明显减少,25.0 mm以上降水日数明显增加。以1986年为界的气候变暖前后25.1～50.0 mm级别的降水日数夏季和年增加的显著性概率分别达到了5%和1%,降水频率分布呈现向高级别降水量增加的变化趋势。 相似文献
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Adaptation to climate change in Africa: Challenges and opportunities identified from Ethiopia 总被引：6，自引：0，他引：6
Africa is widely held to be highly vulnerable to future climate change and Ethiopia is often cited as one of the most extreme examples. With this in mind we seek to identify entry points to integrate short- to medium-term climate risk reduction within development activities in Africa, drawing from experiences in Ethiopia. To achieve this we employ a range of data and methods. We examine the changing nature of climate risks using analysis of recent climate variability, future climate scenarios and their secondary impacts. We assess the effects of climate variability on agricultural production and national GDP. Entry points and knowledge gaps in relation to mainstreaming climate risks in Ethiopia are identified using the Government's plan for poverty reduction. We end with a case study incorporating climate risks through drought insurance within the current social protection programme in Ethiopia, which provides support to 8.3 million people.Rainfall behaviour in Ethiopia shows no marked emergent changes and future climate projections show continued warming but very mixed patterns of rainfall change. Economic analysis highlights sensitivities within the economy to large-scale drought, however, while the effects are clear in major drought years in other years the relationship is weak. For social protection fairly small positive and negative effects on the number of recipients and frequency of cash payments during drought occur under the extreme range of climate model rainfall projections (2020s).Our analysis highlights several important challenges and opportunities for addressing climate risks. Challenges primarily relate to the large uncertainties in climate projections for parts of Africa, a weak evidence base of complex, often non-deterministic, climate-society interactions and institutional issues. Opportunities relate to the potential for low-regrets measures to reduce vulnerability to current climate variability which can be integrated with relatively modest effort within a shift in Africa from a disaster-focused view of climate to a long-term perspective that emphasises livelihood security and vulnerability reduction. 相似文献
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Joanna Pardoe Declan Conway Emilinah Namaganda Katharine Vincent Andrew J. Dougill Japhet J. Kashaigili 《Climate Policy》2018,18(7):863-877
The threat of climate change is emerging at a time of rapid growth for many economies in sub-Saharan Africa (SSA). Dominant narratives comprising ambitious development plans are common and often based around sectors with strong inter-dependencies that are highly exposed to climate variability. Using document analysis and key informant interviews, this article examines how climate change is addressed in policy, how it is being mainstreamed into water, energy and agriculture sector policies and the extent to which cross-sectoral linkages enable coordinated action. These questions are addressed through a case study of Tanzania, highlighting broader lessons for other developing countries, particularly those in SSA facing similar challenges. The article finds that, while the agriculture and water sectors are increasingly integrating climate change into policies and plans in Tanzania, practical coordination on adaptation remains relatively superficial. Publication of the Tanzania National Adaptation Plan of Action (NAPA) in 2007 marked a step change in the integration of climate change in sectoral policies and plans; however, it may have reinforced a sectoral approach to climate change. Examining the policies for coherence highlights overlaps and complementarities which lend themselves to a coordinated approach. Institutional constraints (particularly structures and resources) restrict opportunities for inter-sectoral action and thus collaboration is confined to ad hoc projects with mixed success to date. The results highlight the need for institutional frameworks that recognize and address these constraints to enable development goals to be pursued in a more sustainable and climate-resilient manner.
KEY POLICY INSIGHTS
The NAPA has been successful at encouraging climate change mainstreaming into sectoral policies in Tanzania; however, the cross-sectoral collaboration crucial to implementing adaptation strategies remains limited due to institutional challenges such as power imbalances, budget constraints and an ingrained sectoral approach.
Collaboration between nexus sectors in Tanzania is largely through ad hoc projects with limited progress on establishing deeper connections to enable collaboration as a process. Regular cross-sectoral planning meetings and consistent annual budgets could provide a platform to enhance cross-sectoral coordination.
Plans to develop hydropower and agriculture are prevalent across sub-Saharan Africa. Insights from Tanzania highlight the importance of institutional and policy frameworks that enable cross-sectoral coordination.
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Declan G. De Paor 《Tectonophysics》1981,73(4):T9-T14
This paper describes a new technique of strain analysis using passively deformed linear markers which were initially uniformly or symmetrically distributed in a plane. The axial ratio of the strain ellipse is determined from the quartiles or other percentiles of the deformed distribution. The technique permits statistical testing of assumptions and rapid reconstruction of the undeformed state. 相似文献
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Declan G. De Paor 《Physics of the Earth and Planetary Interiors》1985,39(3):208-209
The dynamic recrystallisation mechanisms in a magnesium alloy have been investigated during uniaxial large strain compression at T = 0.7?0.95 Tm (Tm = melting temperature). Previous work at T = 0.45?0.64 Tm has shown that the metal is a useful analogue for minerals with a high plastic anisotropy.The high strain microstructures were akin to those in high grade tectonites. Initial grain sizes and shapes had been completely transformed with the recrystallised grainsize related solely to the flow stress. Two processes were responsible for the transformation, grain boundary migration and the formation of new high angle boundaries by progressive misorientation across subgrain boundaries. Estimates of the grain boundary migration velocity suggest that solute-escape migration does not occur.This type of recrystallisation mechanism where grain boundary migration and subgrain rotation are equally involved has not previously been described. A ‘recrystallisation mechanism diagram’ has been produced to show the relationship of this mechanism, to other recrystallisation mechanisms. In the diagram a particular mechanism is defined in terms of the relative contribution of the following processes; subgrain rotation, subgrain growth, grain boundary bulging and grain growth. Consideration of normalised experimentally defined stress grain size relationships reveals that there is a systematic relationship between the normalised stress grain size relationship and the type of recrystallisation mechanism, as defined by the ‘mechanism diagram’.The implications of these results to the interpretation of upper mantle olivine palaeoblast grain size profiles (Ave Lallement et al.) are discussed. 相似文献
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