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4.
Artigo em Inglês | MEDLINE | ID: mdl-31438517

RESUMO

There is great potential for reducing greenhouse gas emissions (GHGE) from public-sector meals. This paper aimed to develop a strategy for reducing GHGE in the Swedish school food supply while ensuring nutritional adequacy, affordability, and cultural acceptability. Amounts, prices and GHGE-values for all foods and drinks supplied to three schools over one year were gathered. The amounts were optimized by linear programming. Four nutritionally adequate models were developed: Model 1 minimized GHGE while constraining the relative deviation (RD) from the observed food supply, Model 2 minimized total RD while imposing stepwise GHGE reductions, Model 3 additionally constrained RD for individual foods to an upper and lower limit, and Model 4 further controlled how pair-wise ratios of 15 food groups could deviate. Models 1 and 2 reduced GHGE by up to 95% but omitted entire food categories or increased the supply of some individual foods by more than 800% and were deemed unfeasible. Model 3 reduced GHGE by up to 60%, excluded no foods, avoided high RDs of individual foods, but resulted in large changes in food-group ratios. Model 4 limited the changes in food-group ratios but resulted in a higher number of foods deviating from the observed supply and limited the potential of reducing GHGE in one school to 20%. Cost was reduced in almost all solutions. An omnivorous, nutritionally adequate, and affordable school food supply with considerably lower GHGE is achievable with moderate changes to the observed food supply; i.e., with Models 3 and 4. Trade-offs will always have to be made between achieving GHGE reductions and preserving similarity to the current supply.


Assuntos
Dieta , Abastecimento de Alimentos , Efeito Estufa/prevenção & controle , Modelos Teóricos , Política Nutricional , Instituições Acadêmicas , Custos e Análise de Custo , Cultura , Ingestão de Energia , Alimentos , Abastecimento de Alimentos/economia , Gases de Efeito Estufa , Humanos , Política Nutricional/economia , Programação Linear , Instituições Acadêmicas/economia , Suécia
5.
Environ Sci Pollut Res Int ; 26(29): 30313-30323, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31432372

RESUMO

The Paris agreement (2015) seems a significant achievement towards a global mitigation policy to climate change. However, implementing the promised Intended Nationally Determined Contribution (INDC) targets by the participating countries has become a real challenge. In this aspect, the input-output life cycle assessment (IO-LCA) model provides an important assessment mechanism to design suitable abatement policies limiting the rising greenhouse gas (GHG) emissions. The present paper develops an IO-LCA model for Pakistan and estimates all the direct and indirect GHG emissions caused by all the production activities during all the stages of production. This task is achieved in three phases. In phase 1, the Pakistan input-output table (IOT) is constructed. In phase 2, the GHG environmental satellite accounts are created for each sector in the economy. In phase 3, the GHG emissions are linked to different categories of final demand.


Assuntos
Pegada de Carbono/economia , Desenvolvimento Econômico/tendências , Política Ambiental/economia , Efeito Estufa , Modelos Teóricos , Mudança Climática , Congressos como Assunto , Efeito Estufa/economia , Efeito Estufa/prevenção & controle , Paquistão , Formulação de Políticas
6.
Nature ; 572(7767): 51-55, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31367029

RESUMO

The cooling of the Earth's climate through the effects of anthropogenic aerosols on clouds offsets an unknown fraction of greenhouse gas warming. An increase in the amount of water inside liquid-phase clouds induced by aerosols, through the suppression of rain formation, has been postulated to lead to substantial cooling, which would imply that the Earth's surface temperature is highly sensitive to anthropogenic forcing. Here we provide direct observational evidence that, instead of a strong increase, aerosols cause a relatively weak average decrease in the amount of water in liquid-phase clouds compared with unpolluted clouds. Measurements of polluted clouds downwind of various anthropogenic sources-such as oil refineries, smelters, coal-fired power plants, cities, wildfires and ships-reveal that aerosol-induced cloud-water increases, caused by suppressed rain formation, and decreases, caused by enhanced evaporation of cloud water, partially cancel each other out. We estimate that the observed decrease in cloud water offsets 23% of the global climate-cooling effect caused by aerosol-induced increases in the concentration of cloud droplets. These findings invalidate the hypothesis that increases in cloud water cause a substantial climate cooling effect and translate into reduced uncertainty in projections of future climate.


Assuntos
Aerossóis/análise , Aerossóis/química , Mudança Climática/estatística & dados numéricos , Atividades Humanas , Modelos Teóricos , Temperatura Ambiente , Água/análise , Água/química , Poluição do Ar/análise , Efeito Estufa/prevenção & controle , Efeito Estufa/estatística & dados numéricos , Chuva , Incerteza
7.
Artigo em Inglês | MEDLINE | ID: mdl-31349658

RESUMO

National committed greenhouse gas emission reduction actions are the center of the Paris Agreement, and are known as 'Intended Nationally Determined Contributions' (INDC) that aim to slow down global warming. The climate response to INDC emission reduction is a focus in climate change science. In this study, data from 32 global climate models from the Coupled Model Intercomparison Project Phase 5 (CMIP5) were applied to investigate the changes in the mean and extreme high temperatures in Central Asia (CA) under the INDC scenario above the present-day level. The results show that the magnitude of warming in CA is remarkably higher than the global mean. Almost all the regions in CA will experience more intense, more frequent, and longer-lasting extreme high-temperature events. In comparison with the INDC scenario, the reduced warming of the 2.0 °C/1.5 °C target scenarios will help avoid approximately 44-61%/65-80% of the increase in extreme temperature events in terms of the intensity, frequency, and duration in CA. These results contribute to an improved understanding of the benefits of limiting global warming to the 2.0 °C/1.5 °C targets, which is paramount for mitigation and adaptation planning.


Assuntos
Mudança Climática/estatística & dados numéricos , Monitoramento Ambiental/métodos , Aquecimento Global/prevenção & controle , Aquecimento Global/estatística & dados numéricos , Efeito Estufa/prevenção & controle , Temperatura Alta , Ásia , Efeito Estufa/estatística & dados numéricos , Modelos Teóricos
8.
Genet Sel Evol ; 51(1): 18, 2019 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-31035930

RESUMO

BACKGROUND: Societal pressures exist to reduce greenhouse gas (GHG) emissions from farm animals, especially in beef cattle. Both total GHG and GHG emissions per unit of product decrease as productivity increases. Limitations of previous studies on GHG emissions are that they generally describe feed intake inadequately, assess the consequences of selection on particular traits only, or examine consequences for only part of the production chain. Here, we examine GHG emissions for the whole production chain, with the estimated cost of carbon included as an extra cost on traits in the breeding objective of the production system. METHODS: We examined an example beef production system where economic merit was measured from weaning to slaughter. The estimated cost of the carbon dioxide equivalent (CO2-e) associated with feed intake change is included in the economic values calculated for the breeding objective traits and comes in addition to the cost of the feed associated with trait change. GHG emission effects on the production system are accumulated over the breeding objective traits, and the reduction in GHG emissions is evaluated, for different carbon prices, both for the individual animal and the production system. RESULTS: Multiple-trait selection in beef cattle can reduce total GHG and GHG emissions per unit of product while increasing economic performance if the cost of feed in the breeding objective is high. When carbon price was $10, $20, $30 and $40/ton CO2-e, selection decreased total GHG emissions by 1.1, 1.6, 2.1 and 2.6% per generation, respectively. When the cost of feed for the breeding objective was low, selection reduced total GHG emissions only if carbon price was high (~ $80/ton CO2-e). Ignoring the costs of GHG emissions when feed cost was low substantially increased emissions (e.g. 4.4% per generation or ~ 8.8% in 10 years). CONCLUSIONS: The ability to reduce GHG emissions in beef cattle depends on the cost of feed in the breeding objective of the production system. Multiple-trait selection will reduce emissions, while improving economic performance, if the cost of feed in the breeding objective is high. If it is low, greater growth will be favoured, leading to an increase in GHG emissions that may be undesirable.


Assuntos
Criação de Animais Domésticos/economia , Criação de Animais Domésticos/métodos , Gases de Efeito Estufa/análise , Ração Animal/análise , Animais , Cruzamento , Bovinos/genética , Indústria de Laticínios/métodos , Feminino , Flatulência , Efeito Estufa/prevenção & controle , Gases de Efeito Estufa/metabolismo , Masculino , Leite , Fenótipo , Carne Vermelha
9.
Nat Commun ; 10(1): 2165, 2019 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-31092825

RESUMO

Mental disorders have been associated with various aspects of anthropogenic change to the environment, but the relative effects of different drivers are uncertain. Here we estimate associations between multiple environmental factors (air quality, residential greenness, mean temperature, and temperature variability) and self-assessed mental health scores for over 20,000 Chinese residents. Mental health scores were surveyed in 2010 and 2014, allowing us to link changes in mental health to the changes in environmental variables. Increases in air pollution and temperature variability are associated with higher probabilities of declined mental health. Mental health is statistically unrelated to mean temperature in this study, and the effect of greenness on mental health depends on model settings, suggesting a need for further study. Our findings suggest that the environmental policies to reduce emissions of air pollution or greenhouse gases can improve mental health of the public in China.


Assuntos
Poluição do Ar/efeitos adversos , Transtornos Mentais/epidemiologia , Saúde Mental/tendências , Adolescente , Adulto , Idoso , Poluição do Ar/prevenção & controle , China/epidemiologia , Política Ambiental , Feminino , Efeito Estufa/prevenção & controle , Gases de Efeito Estufa/efeitos adversos , Humanos , Masculino , Transtornos Mentais/etiologia , Saúde Mental/estatística & dados numéricos , Pessoa de Meia-Idade , Estações do Ano , Autoavaliação , Temperatura Ambiente , Adulto Jovem
12.
Environ Sci Pollut Res Int ; 26(16): 16053-16075, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30968296

RESUMO

A plethora of empirical work explored finance-income-environment nexus, aims to investigate high CO2 emissions determinants, over the last few couples of decades. The prior empirical work assist the idea that finance and income have diverse impacts on the environment. The lack of consensus on finance-income-environment nexus in the Central and Eastern European Countries in the perspective of Belt and Road Initiative need to be examined. Therefore, the present study explores the nexus between financial development, income level, and environmental quality for a panel of eighteen Central and Eastern European Countries, over the period of 1980-2016. The Dynamic Seemingly Unrelated Regression, the Fully Modified Ordinary Least Squares, and the Dumitrescu-Hurlin panel casualty approaches are employed. The environmental Kuznets curve hypothesis also investigated for both time series panel and country-wise. The Dynamic Seemingly Unrelated Regression long-run panel results reveal that (i) financial development index and income negatively impact on environmental quality; (ii) energy consumption is the key determinant of CO2 emissions and reduces environmental quality; (iii) urbanization and trade both enhance environmental quality via reduction of carbon emissions; and (iv) the environmental Kuznets curve hypothesis supported for the selected panel countries. The country-wise results depict that increase in environmental quality occurs due to increase in financial development (in four countries), income level (in five countries), trade (in five countries), and urbanization (in eight countries). However, the environmental quality decreases due to the increase in financial development (in six countries), income level (in eight countries), energy consumption (in twelve countries), trade (in six countries), and urbanization (in five countries). The environmental Kuznets curve hypothesis supported for five Central and Eastern European Countries. Additionally, the causality results confirmed the presence of feedback relationships among income and environmental quality, and financial development and energy consumption. Thus, we conclude that income level and financial development are the main drivers behind high carbon dioxide emissions in CEECs. The finding of the study opens up new insight for appropriate policymaking.


Assuntos
Dióxido de Carbono , Meio Ambiente , Efeito Estufa/prevenção & controle , Renda , China , Europa (Continente) , Administração Financeira , Cooperação Internacional , Modelos Teóricos , Classe Social , Urbanização
14.
Environ Monit Assess ; 191(2): 90, 2019 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-30666420

RESUMO

Reducing agricultural greenhouse gas (GHG) emissions is attracting increasing attention. Balanced fertilization (BF) of cropland has been widely promoted and applied and has great potential to reduce GHG emissions. This study assesses GHG mitigation of BF cropland systems including winter wheat and summer maize double-cropping system (wheat-maize) and winter oilseed rape (Brassica napus) and rice double-cropping system (rape-rice) in Shaanxi province, China. We determined the boundaries, scenarios, leakage, and sources of GHG mitigation and developed a measurement system for GHG mitigation under these cropping systems for BF farmland. In the measurement system, except for the changes in nitrogen fertilizer rates, soil carbon storage, mechanical fuel consumption, and fertilizer management mode (paddy), change in crop yield was recommended as a primary source of GHG mitigation. The BF cropland areas of wheat-maize and rape-rice were 2818.89 ha and 1671.73 ha, respectively. The use of BF reduced the GHG emissions of wheat-maize by 1.15 tCO2 equivalent (CO2e) ha-1 per year and the emissions of rape-rice by 1.05 tCO2e ha-1 per year. The BF cropland produced 5007.6 tCO2e per year. Our results do not only provide a reference for the assessment of GHG mitigation on BF cropland under double-cropping systems, but also will be helpful for improving the methodology of GHG mitigation on BF cropland.


Assuntos
Produção Agrícola/métodos , Produtos Agrícolas/crescimento & desenvolvimento , Monitoramento Ambiental/métodos , Fertilizantes/análise , Efeito Estufa/prevenção & controle , Gases de Efeito Estufa/análise , China , Fazendas , Estações do Ano , Solo/química
15.
Proc Natl Acad Sci U S A ; 116(12): 5270-5276, 2019 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-30254151

RESUMO

In this paper we present a simple model for assessing the willingness to pay for reductions in the risk associated with catastrophic climate change. The model is extremely tractable and applies to a multiregion world but with global externalities and has five key features: (i) Neither the occurrence nor the costs of a catastrophic event in any one year are precisely predictable; (ii) the probability of a catastrophe occurring in any one year increases as the levels of greenhouse gases in the atmosphere increase; (iii) greenhouse gases are a worldwide public bad with emissions from any one country or region increasing the risks for all; (iv) there is two-sided irreversibility; if nothing is done and the problem proves serious, the climate, economic activity, and human life will suffer permanent damage, but if we spend large sums on countermeasures and the problem turns out to be minor or even nonexistent, we will have wasted resources unnecessarily; and (v) technological progress may yield partial or even complete solutions. The framework that we propose can give a sense of the quantitative significance of mitigation strategies. We illustrate these for a core set of parameter values.


Assuntos
Mudança Climática/estatística & dados numéricos , Conservação dos Recursos Naturais/legislação & jurisprudência , Atmosfera , Efeito Estufa/prevenção & controle , Gases de Efeito Estufa/análise , Humanos , Políticas
16.
17.
Nature ; 564(7735): 249-253, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30542169

RESUMO

Land-use changes are critical for climate policy because native vegetation and soils store abundant carbon and their losses from agricultural expansion, together with emissions from agricultural production, contribute about 20 to 25 per cent of greenhouse gas emissions1,2. Most climate strategies require maintaining or increasing land-based carbon3 while meeting food demands, which are expected to grow by more than 50 per cent by 20501,2,4. A finite global land area implies that fulfilling these strategies requires increasing global land-use efficiency of both storing carbon and producing food. Yet measuring the efficiency of land-use changes from the perspective of greenhouse gas emissions is challenging, particularly when land outputs change, for example, from one food to another or from food to carbon storage in forests. Intuitively, if a hectare of land produces maize well and forest poorly, maize should be the more efficient use of land, and vice versa. However, quantifying this difference and the yields at which the balance changes requires a common metric that factors in different outputs, emissions from different agricultural inputs (such as fertilizer) and the different productive potentials of land due to physical factors such as rainfall or soils. Here we propose a carbon benefits index that measures how changes in the output types, output quantities and production processes of a hectare of land contribute to the global capacity to store carbon and to reduce total greenhouse gas emissions. This index does not evaluate biodiversity or other ecosystem values, which must be analysed separately. We apply the index to a range of land-use and consumption choices relevant to climate policy, such as reforesting pastures, biofuel production and diet changes. We find that these choices can have much greater implications for the climate than previously understood because standard methods for evaluating the effects of land use4-11 on greenhouse gas emissions systematically underestimate the opportunity of land to store carbon if it is not used for agriculture.


Assuntos
Agricultura/estatística & dados numéricos , Biocombustíveis/estatística & dados numéricos , Pegada de Carbono/estatística & dados numéricos , Conservação dos Recursos Naturais/métodos , Dieta/estatística & dados numéricos , Efeito Estufa/prevenção & controle , Solo/química , Animais , Biocombustíveis/provisão & distribução , Brasil , Sequestro de Carbono , Conservação dos Recursos Naturais/estatística & dados numéricos , Produtos Agrícolas/metabolismo , Fertilizantes/provisão & distribução , Abastecimento de Alimentos , Agricultura Florestal/estatística & dados numéricos , Florestas , Aquecimento Global/prevenção & controle , Humanos , Gado/metabolismo , Chuva
19.
PLoS One ; 13(11): e0206680, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30383842

RESUMO

Maintaining crop outputs to feed its large population with limited resources while simultaneously mitigating carbon emissions are great challenges for China. Improving the efficiency of resource use in crop production is important in reducing carbon emissions. This paper constructs a methodological framework combining emergy-based indicator accounting and a nonseparable undesirable output slack-based measurement (SBM) data envelopment analysis (DEA) model. This framework is used to explore the efficiency of inputs and outputs and the greenhouse gas (GHG) emissions reduction potential for crop production systems, using Zhejiang province, China, as a case study. It is found that an emergy synthesis and a nonseparable undesirable output SBM-DEA framework is compatible with the case study. Crop production in Zhejiang province has relied heavily on an increase in agrochemical inputs to maintain agricultural output. Energy and chemical fertilizer use are determined as the province's major carbon emissions sources. Although carbon emissions per unit of monetary output has decreased sharply, the carbon emissions per unit emergy output has increased, demonstrating a high carbon intensity reality. The DEA highlighted the differences in crop production efficiency, resource factor redundancy and carbon mitigation potential in the different prefectures of the province. To conclude this research, policies to support low carbon agriculture development, including subsidizing low carbon agriculture technology development and expansion and the cancellation of subsidies to high carbon production factors, such as chemical fertilizer production and sales, are discussed to conclude the research.


Assuntos
Produção Agrícola , Efeito Estufa/prevenção & controle , Gases de Efeito Estufa , Modelos Teóricos , Agroquímicos , China , Conservação dos Recursos Naturais/métodos , Produção Agrícola/métodos , Eficiência
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