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91.
Global climate change mitigation action is hampered by systematic under-assessment of national ‘fair shares’, largely on the basis of perceived national interests. This paper aims to inform discussions centred on South Africa’s nationally determined contribution (NDC) by estimating (1) emissions reduction pathways for the country using the Climate Equity Reference Calculator (CERC) assuming a maximum 2°C aggregate warming target and (2) the likely economy-wide net mitigation costs or savings associated with reaching these pathways if known lower-cost mitigation measures, identified through the national mitigation potential analysis, are prioritised. The cumulative net savings associated with achieving the CERC ‘fair share’ emissions pathway, assuming the moderate use of low carbon power generation measures, would reach $5.3 billion by 2030. Net savings could be substantially greater reaching $46.8 billion by 2030 assuming power generation focuses on moving towards full decarbonisation. An unconditional commitment to the mitigation action implied by the ‘fair share’ emissions pathway therefore seems reasonable and prudent purely from the point of view of net country-wide savings. Only if power generation moves towards full decarbonisation would there be a reasonable chance of achieving the more ambitious CERC domestic emissions pathway. However, the significant additional cost associated with achieving the domestic emissions pathway should be conditional on international assistance.
Key policy insights
South Africa can only achieve its ‘fair share’ of the global mitigation effort if greater use is made of renewable energy options, and can realise significant net savings if it does so.
Further emissions reductions would incur costs and require significant upscaling of the share of renewable energy and full implementation of all non-power generation mitigation measures available.
Committing to this further mitigation action contingent on international finance would both strengthen the nation’s position in climate negotiations and support the provision of finance for those vulnerable developing nations that bear little or no responsibility for climate change.
92.
International agricultural carbon market projects face significant challenges in delivering greenhouse gas mitigation objectives whilst also seeking to provide additional benefits for poverty alleviation. The carbon credit producer (the smallholder farmer) and carbon credit buyer in the carbon market transaction typically operate at different spatial and temporal scales. Buyers operate at a global scale, responding to opportunities for financial speculation and both private and public climate action plans. Farmers operate within households, farms, and immediate agricultural landscapes, pursuing livelihood and food security needs. These different scales often result in mismatches of timing, payment, and knowledge in market transactions and can be partially rectified by project developers who serve to broker the relationship between the farmers and the buyers. We examined eight East African agricultural carbon market projects to determine how project developers function as bridging organizations and minimize the mismatches between these actors. Results show that projects better bridged the timing and payment gap between buyers and producers when project developers provided non-monetary benefits or direct monetary assistance to farmers. However, knowledge gaps remained a significant barrier for farmers wishing to participate in the market. We discuss how project developers brokered relationships in ways that reflected their interests and highlight the limitations, trade-offs, and challenges that must be overcome if win-win outcomes of poverty alleviation and climate change mitigation are to be realized. 相似文献
93.
Concentration of damage of buildings near the edge of cliff-type topographies has been observed during a number of recent
earthquakes and interpreted by numerical dynamic analyses that illustrate the amplification of the horizontal acceleration
and the generation of parasitic vertical acceleration near the tip of slopes. The paper performs a detailed parametric numerical
analysis to investigate the ability of mitigating this topographic effect using anchors and piles. A typical field case, the
Aegion slope of Greece, is considered. Different input motions are applied. The results illustrated that anchors and piles
can be effective in mitigating the topographic effect. The main issue is that if the part of the slope in which topographic
amplification occurs is connected to that at larger depths, in which the acceleration is smaller, then the accelerations at
the top of the slope have to become more uniform and smaller. For typical diameter and material properties of anchors/piles
the effectiveness of the mitigation depends on the length, inclination, location and number of anchors/piles. An optimum configuration
of anchors/piles mitigating the topographic effect is proposed. 相似文献
94.
The adverse ecological effects of elevated levels of phosphorus (P) and fine sediment (termed silt) in surface waters are a major environmental issue both nationally and internationally. Increasingly, the Water Framework Directive (WFD) will provide the basis for the integrated management of European waters, but there is a more immediate need for action to safeguard designated wildlife sites from the effects of eutrophication and siltation. We outline the policy drivers behind the control of these pollution problems, the nature and extent of ecological risks and approaches to target-based management within catchments. Tackling diffuse sources of P and silt requires accurate apportionment of local sources and contributing areas, and integration of practical action with the development of an improved quantitative understanding of the management changes needed in catchments to meet environmental objectives. Such an approach can be used to refine policies on land-based emissions of these pollutants and operational strategies for control. The critical role of catchment appraisal through modelling within this approach is stressed. Management measures to control agricultural sources of P and silt will also help to address other key catchment management objectives (flood risk management, water resource management, terrestrial and wetland habitat restoration). Climate change predictions indicate that the need for integrated catchment management, to increase the resilience of catchments, wildlife and people to extremes of weather conditions (drought and flood) and temperature trends, has never been greater. 相似文献
95.
SHI Changxing 《国际泥沙研究》1999,(2)
1DEFINITIONOFSEDIMENTHAZARDHazardsaredefinedasthenaturaleventsthatcauselossesofhumanlifeandproperty.Reasonably,thesedimenthazardsarethehazardsoccasionedbythenatUralphenomenonandprocessesthatarerelatedwithsedimenterosion,transport,andaccumulation.Thelandslideandsoilerosionarethedirectresultsofsedimentmovement.Theoccurrenceofsomeotherhazardsisnotthedirectresultofbutrelatedtosedimentmovement.Forexample,inadditiontometeorolog.icalconditions,somekindsoflandformsarefavorabletoformationoff… 相似文献
96.
Landslides are a recognized but poorly studied phenomena in the eastern footslopes of the Aberdare ranges in central Kenya.
The Aberdare ranges traverse the Murang'a, Kiambu, Nyeri and Nyandarua districts of Kenya where fatal landslides have occurred
in the past. A detailed study of a major landslide which occurred at Maringa village in Murang'a district on 30 April 1997,
has been undertaken. The landslide buried three houses at the toe of a slope and killed all the 11 occupants in their sleep.
It is shown that the geology and climate of the study area contribute to the prevalence of landslides not only in Murang'a
but in all the andosol-covered areas throughout the eastern footslopes of Aberdare ranges. Rapid weathering of pyroclastic
rocks in a warm and wet climate create a regolith which is generally weaker than the underlying better-cemented basalt and
basaltic agglomerates. The landsliding occurred when the weathered pyroclastic regolith become saturated after a heavy rainstorm
on high mechanically unstable slope which slid over the more stable basalts. Over-saturation of clay soils (andosol) which
were also derived from weathering of pyroclastic rocks contributed to the slope failure. The results of the study show that
besides fatalities and injuries, the landslide destroyed homes, plantations and roads.
Received: 16 March 1998 · Accepted: 22 September 1998 相似文献
97.
Mitigation options for methane, nitrous oxide and nitric oxide emissions from agricultural ecosystems 总被引：9，自引：0，他引：9
Zheng Xunhu Wang Mingxing Wang Yuesi Shen Renxing Li Jing J. Heyer M. Koegge H. Papen 《大气科学进展》2000,17(1):83-92
1.IntroductionNitrousoxide(N,O)andmethane(CH.)arethemostimportantgreenhousegassesintheatmospherewithitscontributiontoglobalwarmingjustlowerthanCO2.Theirconcentrationsinatmospherehavebeennotedtoincreasecurrentlyattherateof0.25%yr--'andl.02%yr',respectively(IPCC,1995).Atpresent,theincreaseofNZOandCH4intheatmospherehasbeenestimatedtoaccountfor20--25%oftheglobalwarming(FAO&IAEA,1992;Bailes&Bridges,1992).NOdoesnotabsorbradiationdirectlyintheatmosphere,buttheincreasingconcentrationofNOmay… 相似文献
98.
How to share responsibility for greenhouse gas emissions between consumers and producers is a highly sensitive question in international climate policy negotiations. Traditional ‘Production-Based Accounting’ (PBA), which assigns responisibility to the region where emissions are released, has frequently been challenged by ‘Consumption-Based Accounting’ (CBA) schemes that suggest that greenhouse gas emissions generated to produce traded goods and services should be attributed to their final consumers. PBA and CBA both lack a sound foundation in economic theory as they do not consider the economic benefits accruing to producers or consumers if carbon emissions do not carry a price that reflects their social costs. We build on well-established economic theory to derive how to share responsibility for trade-related emissions between producers and consumers and apply this novel approach for the most prominent bilateral trade relationships using multi-regional input–output data. We propose an ‘Economic Benefit Shared Responsibility’ (EBSR) scheme, in which China is attributed significantly higher responsibility for emissions than in CBA, while lower emissions and responsibility are attributed to both the US and the EU. 相似文献
99.
Extreme rainfall-induced debris flow can be catastrophic to an urban area,and installation of slit-type barriers can prevent such damage while minimizing negative impact on environments.However,the performance of slit-type barriers against debris flows remains poorly identified partly due to the innate complexity in interactions between debris flow and solid structure.This paper investigated the flow behaviors of debris affected by slit-type barriers using the computational fluid dynamics(CFD)method,in which the numerical model based on the volume of fluid method was verified using the physical modeling results.The sensitivity analysis was performed by building metamodels to determine the primary parameters influencing the barrier performance against debris flows among various variables,in which the effect of input properties and design parameters,particularly the soil concentration in fluidized debris,initial velocity and volume of debris,the barrier height,and the opening ratio,was evaluated from the perspectives of the flow energy reduction and debris trapping.The initial velocity and volume of debris were found to play a significant role in determining the debris flow characteristics.A decrease in the opening ratio in the channel primarily facilitated the energy reduction and trapping due to the reduced opening size.However,the barrier height exhibited a limited effect when the height was sufficiently high to block the debris flow volume.In addition,it was observed that the double barrier system effectively increased the energy reduction while keeping the benefit of open-type barrier.The developed simulation method and obtained results provide an effective tool and an insight that can contribute to an optimum design of the debris-flow barrier. 相似文献
100.