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The economic evaluation of drought impacts is essential in order to define efficient and sustainable management and mitigation strategies. The aim of this study is to evaluate the economic impacts of a drought event on the agricul...
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The economic evaluation of drought impacts is essential in order to define efficient and sustainable management and mitigation strategies. The aim of this study is to evaluate the economic impacts of a drought event on the agricultural sector and measure how they are transmitted from primary production to industrial output and related employment. We fit econometric models to determine the magnitude of the economic loss attributable to water storage. The direct impacts of drought on agricultural productivity are measured through a direct attribution model. Indirect impacts on agricultural employment and the agri-food industry are evaluated through a nested indirect attribution model. The transmission of water scarcity effects from agricultural production to macroeconomic variables is measured through chained elasticities. The models allow for differentiating the impacts deriving from water scarcity from other sources of economic losses. Results show that the importance of drought impacts are less relevant at the macroeconomic level, but are more significant for those activities directly dependent on water abstractions and precipitation. From a management perspective, implications of these findings are important to develop effective mitigation strategies to reduce drought risk exposure.
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The consequences of poverty and inequality for growth have long preoccupied academics and policy-makers. This paper revisits the inequality-growth and poverty-growth links. Using a panel of 158 countries between 1960 and 2010, we ...
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The consequences of poverty and inequality for growth have long preoccupied academics and policy-makers. This paper revisits the inequality-growth and poverty-growth links. Using a panel of 158 countries between 1960 and 2010, we find that the correlation of growth with poverty is consistently negative: A 10 p.p. decrease in the headcount poverty rate is associated with a subsequent increase in per capita GDP between 0.5 and 1.2% per year. In contrast, the correlation of growth with inequality is empirically fragile-it can be positive or negative, depending on the empirical specifi-cation and econometric approach employed. However, the indirect effect of inequality on growth through its correlation with poverty is robustly negative. Closer inspection shows that these results are driven by the sample observations featuring high poverty rates.
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Fine details of the cross section for electron-impact ionization of metastable two-electron Li~+ (1s2s ~3S_1) ions are scrutinized by both experiment and theory. Beyond direct knockoff ionization, indirect ionizationmechanisms pro...
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Fine details of the cross section for electron-impact ionization of metastable two-electron Li~+ (1s2s ~3S_1) ions are scrutinized by both experiment and theory. Beyond direct knockoff ionization, indirect ionizationmechanisms proceeding via formation of intermediate double-K-vacancy (hollow) states either in a Li~+ ion or in a neutral lithium atom and subsequent emission of one or two electrons, respectively, can contribute to the net production of Li~(2+) ions. The partial cross sections for such contributions are less than 4% of the total single-ionization cross section. The characteristic steps, resonances, and interference phenomena in the indirect ionization contribution are measured with an experimental energy spread of less than 0.9 eV and with a statistical relative uncertainty of the order of 1.7%, requiring a level of statistical uncertainty in the total single-ionization cross section of better than 0.05%. The measurements are accompanied by convergent-close-coupling calculations performed on a fine energy grid. Theory and experiment are in remarkable agreement concerning the fine details of the ionization cross section. Comparison with previous R-matrix results is less favorable.
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Long-term changes in temperature can negatively affect human livelihoods with resulting implications for health outcomes. While increasing attention has been paid to the direct health consequences of climate change, there has been...
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Long-term changes in temperature can negatively affect human livelihoods with resulting implications for health outcomes. While increasing attention has been paid to the direct health consequences of climate change, there has been less focus on indirect health effects, partly due to the relative complexity of establishing and modeling these outcomes. Here, I leverage a dataset of over 400,000 individuals across 25 countries in Sub-Saharan Africa, coupled with high-resolution climate data for the region, to test the effect of long-run temperature changes on HIV prevalence. I find that warmer periods are linked with an increase in HIV prevalence, particularly for younger generations. Both economic and behavioral changes likely drive this linkage: I find evidence that male migration and sex-market use increase with higher temperatures. I generate projections for future HIV prevalence using two methods. First, I project directly using the empirical estimate, an approach frequently used in econometric studies of climate change impacts. Second, I develop a mechanistic model of HIV spread, incorporating the estimated temperature effect. I find that agreement between the models is strong (77%). Under the RCP8.5 scenario for warming, I find that climate change will lead to between 11.6 and 16.0 million additional cases of HIV by 2050, an increase in prevalence of 1.4-2.1 percentage points.
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Responses of infaunal saltmarsh benthic invertebrates to whole-ecosystem fertilization and predator removal were quantified in Plum Island Estuary, Massachusetts, USA. Throughout a growing season, we enriched an experimental creek...
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Responses of infaunal saltmarsh benthic invertebrates to whole-ecosystem fertilization and predator removal were quantified in Plum Island Estuary, Massachusetts, USA. Throughout a growing season, we enriched an experimental creek on each flooding tide to
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The exponential development of the urban real estate sector has become one of the main forces behind the development of China's urban economy. The massive development of urban buildings, however, aggregates domestic environmental ...
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The exponential development of the urban real estate sector has become one of the main forces behind the development of China's urban economy. The massive development of urban buildings, however, aggregates domestic environmental pressures. This study develops a four-quadrant matrix to elaborate the direct and indirect impacts on the construction and operation of urban residential buildings and applies a hybrid life cycle assessment (LCA) method to quantify the overall impacts. The results show that the total energy consumption, water consumption, chemical oxygen demand (COD), ammonia nitrogen (NH_3-N), sulphur dioxide (SO_2), and nitrogen oxides (NO_X) emissions of the overall life span of the urban residential buildings accounted for 5.4%, 5.6%, 3.0%, 3.5%, 3.9%, and 4.0%, respectively, of the national total in 2010. The indirect productive impacts accounted for 76.2% of the energy consumption, 86.4% of the water consumption, and 81.6% of the air pollution emission in 2010. With respect to the potential mitigation alternatives in the next five years, a scenario analysis suggests that a moderate slow-down of the construction of new buildings should be the highest priority, and promoting the application of greener housing materials and more advanced construction techniques should also be desired.
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This paper extends a model from 2003 to separate the direct and indirect impact of an export tax rebate on the intensive margin of firm-level export sales at the subnational level. The direct impact of the rebate is associated wit...
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This paper extends a model from 2003 to separate the direct and indirect impact of an export tax rebate on the intensive margin of firm-level export sales at the subnational level. The direct impact of the rebate is associated with a reduction of an exporting firm's variable costs, while the indirect impact manifests itself through higher regional wages as a result of increased demand for local labor. First, the empirical results imply that a 1 percent rise in the export tax rebate rate increases the export sales among continuing exporters by 0.2 percent through the direct channel. Second, through the indirect channel, a 1 percent difference in the regional rebate causes a 0.02 percent difference in exporters' sales growth. Both effects are statistically significant, and are consistent with the model's predictions.
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Today, many countries are promoting energy efficiency (EE) measures as part of their energy strategy. Among the goals sought with these actions are producing a decoupling between economic growth and energy consumption, reducing th...
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Today, many countries are promoting energy efficiency (EE) measures as part of their energy strategy. Among the goals sought with these actions are producing a decoupling between economic growth and energy consumption, reducing the dependence on fossil fuels as a primary energy source, and reducing greenhouse gas emissions. Measuring direct, indirect, and co-benefit effects of EE programs is crucial. However, in the current literature and practice, assessments of EE programs have focused on direct impacts (i.e., impacts whose energy savings can be directly and instantaneously quantified) due to their objectivity and simplicity to put evaluations in a cost-effectiveness framework. Moreover, several assessment methodologies studying the indirect effects of EE programs only focus on identifying the effects and quantifying a proxy of the effects in terms of the number of activities developed or the number of people attending EE training or dissemination events. Some few existing methodologies correctly assess the indirect effects of EE measures, but they often require a significant budget. We propose a new methodology to assess the impacts of EE programs, especially focusing on indirect effects (i.e., long-term effects on energy use), that is suitable for low-budget programs. We focus on those indirect effects having the capability of mobilizing long-term energy savings through transformations in energy markets. We attempt to measure the potential future energy savings that are sustainable in the long term due to a behavioral transformation of energy markets. In order to measure these indirect effects, we use three axes: presence, valuation, and mobilizing capacity. This methodology was applied to 12 EE programs (implemented during 2011 and 2012 in Chile) in order to obtain their indirect impact assessment.
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Emerging ridesharing travel could be an effective way in China to reduce travel demand by cars, which can further seek to shift personal transportation choices from an owned asset to a service used on demand and lessen the traffic...
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Emerging ridesharing travel could be an effective way in China to reduce travel demand by cars, which can further seek to shift personal transportation choices from an owned asset to a service used on demand and lessen the traffic jam and emissions. Drawing on the raw observed ridesharing trip data provided by DiDi Chuxing company, this study evaluated the direct environmental benefits of ridesharing resulted from the travel mode shift and the indirect environmental benefits resulted from the attitude change towards car purchase behavior. The megacity Beijing is taken as the empirical context given its more serious situation of traffic congestion and difficulties for car purchase. Estimation results show that direct annual energy savings made by ridesharing are approximately 26.6 thousand tce, and annual emission reductions of CO2 and NOx are approximately 46.2 thousand tons and 253.7 tons, respectively. Besides, using ridesharing service will lead to substantial energy savings and emission reductions from the long-term perspective attributing to the weakening willingness on purchasing new cars. Promoting EVs among ridesharing vehicles and switching to clean electricity generation as well as improving vehicle efficiency can further enhance the environmental benefits of ridesharing, with maximum effects amounting to 67% of energy savings and 57% of CO2 emission reductions compared to 2016 level of the fuel related energy consumption and emissions made by ridesharing. (C) 2017 Elsevier Ltd. All rights reserved.
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