An intercomparison of eight climate simulations, each driven with estimated natural and anthropogenic forcings for the last millennium, indicates that the so-called “Erik” simulation of the ECHO-G coupled ocean-atmosphere climate model exhibits atypical behaviour. The ECHO-G simulation has a much stronger cooling trend from 1000 to 1700 and a higher rate of warming since 1800 than the other simulations, with the result that the overall amplitude of millennial-scale temperature variations in the ECHO-G simulation is much greater than in the other models. The MAGICC (Model for the Assessment of Greenhouse-gas-Induced Climate Change) simple climate model is used to investigate possible causes of this atypical behaviour. It is shown that disequilibrium in the initial conditions probably contributes spuriously to the cooling trend in the early centuries of the simulation, and that the omission of tropospheric sulphate aerosol forcing is the likely explanation for the anomalously large recent warming. The simple climate model results are used to adjust the ECHO-G Erik simulation to mitigate these effects, which brings the simulation into better agreement with the other seven models considered here and greatly reduces the overall range of temperature variations during the last millennium simulated by ECHO-G. Smaller inter-model differences remain which can probably be explained by a combination of the particular forcing histories and model sensitivities of each experiment. These have not been investigated here, though we have diagnosed the effective climate sensitivity of ECHO-G to be 2.39±0.11 K for a doubling of CO2. 相似文献
Although participatory approaches to geographic information system (GIS) use have significantly altered the technological and social practices of GIS‐based research and decision making, they have received relatively little attention within discussions of participatory research. This paper examines how participation and representation are negotiated in participatory GIS research through everyday practices of knowledge production. Inclusion and exclusion in the production of knowledge in participatory GIS are mediated within several intersecting arenas of research practice simultaneously, often with contradictory implications, priorities, and outputs. 相似文献
Government policies for the use of publicly owned environmental resources in Australia are often justified as being for the economic good of the nation. Yet there has been little enquiry about how Australians perceive economic good in the context of the use of environmental resources. The residents of five State government electorates of Perth and one in regional south west Western Australia were surveyed. Their perceptions of economics, the environment and resources in relation to public policy were assessed. The differences in the responses were greater between the different electorates, than between the different socio-economic strata within the same electorate. This paper examines the spatial variability of the results and raises the possibility of developing a socio-locational indicator of attitudes which could provide a tool for policy implementation. 相似文献
In both nature and synthetic experiments, the common iron oxide haematite (α‐Fe2O3) can incorporate significant amounts of U into its crystal structure and retain radiogenic Pb over geological time. Haematite is a ubiquitous component of many ore deposit types and, therefore, represents a valuable hydrothermal mineral geochronometer, allowing direct constraints to be placed on the timing of ore formation and upgrading. However, to date, no suitable natural haematite reference material has been identified. Here, a synthetic haematite U‐Pb reference material (MR‐HFO) is characterised using LA‐ICP‐MS and ID‐TIMS. Centimetre‐scale ‘chips’ of synthesised α‐Fe2O3 were randomly microsampled via laser ablation‐extraction and analysed using ID‐TIMS. Reproducible U/Pb and Pb/Pb measurements were obtained across four separate chips (n = 13). Subsequently, an evaluation of the suitability MR‐HFO in constraining U‐Pb data via LA‐ICP‐MS is presented using a selection of natural samples ranging from Cenozoic to Proterozoic in age. The MR‐HFO normalised U‐Pb ratios are more concordant and ages more accurate versus the same LA‐ICP‐MS spot analyses normalised to zircon reference material, when compared with independently acquired ID‐TIMS data from the same natural haematite grains. Results establish MR‐HFO as a suitable reference material for LA‐ICP‐MS haematite U‐Pb geochronology. 相似文献
Since the UK introduced a Climate Change Act (CCA) in 2008, similar legislation has followed in a number of states, with each having a slightly different take. What unites these examples is that they all represent framework legislation that aims to facilitate climate change mitigation by creating continuous policy processes whereby mechanisms for the reduction of greenhouse gas (GHG) emissions are developed and implemented. This article is concerned with the extent to which they are living policy processes or rather symbolic gestures. We analyse seven European CCAs with regard to GHG emission reduction targets, planning/implementation mechanisms, and feedback/evaluations prescribed by the laws. These three features correspond with three aspects of climate policy integration (CPI): interpretations of CPI as a norm; CPI as a process of governing; CPI as a policy outcome. We show that CCAs address all three aspects of CPI and constitute living policy processes, although to varying extents. However, CCAs are also policy processes in that they are part of a political system, affected by political forces external to the legislation, positively and negatively.
Key policy insights
CCAs can provide a normative basis for policymaking on climate change at the national level, especially through quantitative emission reduction targets.
Whilst CCAs can bring some stability and predictability to policymaking on climate change (mainly because legislation is more difficult to amend or remove than policy strategies), they are still vulnerable to political developments.
Most CCAs lack either short/medium-term (Denmark, Finland, Ireland, Sweden) or long-term (Austria) targets. Given EU Member States’ aim to decarbonise in the next three decades and the Paris Agreement's global goal of pursuing efforts to limit warming to 1.5°C, states need to find ways to guide this process. One approach could be the inclusion of short-term, medium-term and long-term targets in their CCAs.
Since sanctioning mechanisms are lacking across all the CCAs analysed here, it is not clear what will happen if legally binding targets are not met. Just as it is difficult to imagine speed limits and speed cameras without accompanying penalties, it is hard to imagine how CCAs without sanctions can deliver decarbonization.
We assess women’s perceptions of health risks in relation to quality of life concerns, with attention to variables viewed as central to maintaining or improving health and well-being. In this paper, we specifically underscore how a life-threatening disease—malaria—is experienced and bio-cyclically understood and managed in relation to seasonal hunger, food insecurities, and livelihood vulnerabilities. The study, conducted June–July 2013, draws on field data and interviews with 60 women farmers of the Luhya community along the Yala River in Kakamega County, Western Province, Kenya. Major findings suggest the following: (1) women’s perceived desired quality of life is shaped by priorities for children’s education, nutrition, food security, and economic security in their rural communities; (2) malaria emerged as a challenging household health problem that curtails livelihood opportunities for most study participants; and (3) local understandings of malaria transmission, particularly how and when female mosquitoes become infected with malaria-causing protozoans, was low, but malaria symptoms were relatively well-understood. The interest and motivation to institute new malaria risk reduction practices at the community level are explored, including attention to building upon the Luhya tradition of oral storytelling in order to promote actions to eliminate malaria. This analysis of local narratives of health risks illustrates these points and demonstrates how women’s constructions of health risks and well-being provide a basis for developing interventions targeting income generation and microloan opportunities that could support Kenyan women in their intersecting approaches to malaria, securing nutritious diets, and enhancing the local health environment. 相似文献
Natural Hazards - The south coast of Java has a long history of deadly seismogenic tsunamis. The most recent tsunami events in 1994 and 2006 killed hundreds due to lack of awareness and... 相似文献
Abstract— We used the nuclear reaction 37Cl (n,γ) 38Ar, achieved during neutron irradiation for dating meteorites by the 39Ar‐40Ar technique, to calculate the elemental Cl concentration of 132 samples of 94 different meteorites (mostly finds) representing several different classes. determined k and ca concentrations are also reported. Total [Cl] varies considerably, both among meteorites of the same class and among different meteorite classes. The range in [Cl] is approximately 15–177 ppm for ordinary chondrites; approximately 24–650 ppm for enstatite chondrites; approximately 4–177 ppm for eucrites; approximately 7–128 ppm for mesosiderites; approximately 35–268 ppm for acapulcoites and lodranites; and approximately 12–507 ppm for winonaites and iron silicates. As expected, most differentiated meteorites have lower [Cl] compared to chondrites and iron silicates. Analyses of 11 interior samples (~0.1 g each) of a large L6 chondrite varied over 68–129 ppm, which is a measure of the homogeneity of Cl distribution. By evaluating Ar release during stepwise sample degassing, we separated the Cl into low‐temperature and high‐temperature components, the former of which may consist of terrestrial contamination. Most samples show low‐temperature Cl concentrations of <40 ppm, but for several samples terrestrial Cl contamination constitutes significant fractions of the total Cl. Among most differentiated meteorites, finds show considerably greater low‐temperature [Cl] compared to falls. 相似文献