Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 647
Filtrar
3.
Nature ; 583(7815): 242-248, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32641817

RESUMO

Enhanced silicate rock weathering (ERW), deployable with croplands, has potential use for atmospheric carbon dioxide (CO2) removal (CDR), which is now necessary to mitigate anthropogenic climate change1. ERW also has possible co-benefits for improved food and soil security, and reduced ocean acidification2-4. Here we use an integrated performance modelling approach to make an initial techno-economic assessment for 2050, quantifying how CDR potential and costs vary among nations in relation to business-as-usual energy policies and policies consistent with limiting future warming to 2 degrees Celsius5. China, India, the USA and Brazil have great potential to help achieve average global CDR goals of 0.5 to 2 gigatonnes of carbon dioxide (CO2) per year with extraction costs of approximately US$80-180 per tonne of CO2. These goals and costs are robust, regardless of future energy policies. Deployment within existing croplands offers opportunities to align agriculture and climate policy. However, success will depend upon overcoming political and social inertia to develop regulatory and incentive frameworks. We discuss the challenges and opportunities of ERW deployment, including the potential for excess industrial silicate materials (basalt mine overburden, concrete, and iron and steel slag) to obviate the need for new mining, as well as uncertainties in soil weathering rates and land-ocean transfer of weathered products.


Assuntos
Agricultura , Dióxido de Carbono/isolamento & purificação , Produtos Agrícolas , Sedimentos Geológicos/química , Aquecimento Global/prevenção & controle , Objetivos , Silicatos/química , Atmosfera/química , Brasil , China , Política Ambiental/economia , Política Ambiental/legislação & jurisprudência , Aquecimento Global/economia , Índia , Ferro/isolamento & purificação , Mineração , Política , Probabilidade , Silicatos/isolamento & purificação , Aço/isolamento & purificação , Temperatura , Fatores de Tempo , Estados Unidos
4.
Nature ; 583(7814): 72-77, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32612223

RESUMO

Forests provide a series of ecosystem services that are crucial to our society. In the European Union (EU), forests account for approximately 38% of the total land surface1. These forests are important carbon sinks, and their conservation efforts are vital for the EU's vision of achieving climate neutrality by 20502. However, the increasing demand for forest services and products, driven by the bioeconomy, poses challenges for sustainable forest management. Here we use fine-scale satellite data to observe an increase in the harvested forest area (49 per cent) and an increase in biomass loss (69 per cent) over Europe for the period of 2016-2018 relative to 2011-2015, with large losses occurring on the Iberian Peninsula and in the Nordic and Baltic countries. Satellite imagery further reveals that the average patch size of harvested area increased by 34 per cent across Europe, with potential effects on biodiversity, soil erosion and water regulation. The increase in the rate of forest harvest is the result of the recent expansion of wood markets, as suggested by econometric indicators on forestry, wood-based bioenergy and international trade. If such a high rate of forest harvest continues, the post-2020 EU vision of forest-based climate mitigation may be hampered, and the additional carbon losses from forests would require extra emission reductions in other sectors in order to reach climate neutrality by 20503.


Assuntos
Agricultura Florestal/estatística & dados numéricos , Agricultura Florestal/tendências , Florestas , Biodiversidade , Biomassa , Sequestro de Carbono , Monitoramento Ambiental , Política Ambiental/economia , Política Ambiental/legislação & jurisprudência , Europa (Continente) , União Europeia/economia , Agricultura Florestal/economia , Agricultura Florestal/legislação & jurisprudência , Aquecimento Global/prevenção & controle , História do Século XXI , Imagens de Satélites , Madeira/economia
9.
PLoS One ; 15(5): e0230961, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32374737

RESUMO

Is it appropriate for scientists to engage in political advocacy? Some political critics of scientists argue that scientists have become partisan political actors with self-serving financial agendas. However, most scientists strongly reject this view. While social scientists have explored the effects of science politicization on public trust in science, little empirical work directly examines the drivers of scientists' interest in and willingness to engage in political advocacy. Using a natural experiment involving the U.S. National Science Foundation Graduate Research Fellowship (NSF-GRF), we causally estimate for the first time whether scientists who have received federal science funding are more likely to engage in both science-related and non-science-related political behaviors. Comparing otherwise similar individuals who received or did not receive NSF support, we find that scientists' preferences for political advocacy are not shaped by receiving government benefits. Government funding did not impact scientists' support of the 2017 March for Science nor did it shape the likelihood that scientists donated to either Republican or Democratic political groups. Our results offer empirical evidence that scientists' political behaviors are not motivated by self-serving financial agendas. They also highlight the limited capacity of even generous government support programs to increase civic participation by their beneficiaries.


Assuntos
Comportamento/ética , Financiamento Governamental , Pessoal de Laboratório/ética , Política , Política Ambiental/economia , Política Ambiental/legislação & jurisprudência , Financiamento Governamental/ética , Financiamento Governamental/normas , Programas Governamentais/economia , Programas Governamentais/ética , Programas Governamentais/normas , Política de Saúde/economia , Política de Saúde/legislação & jurisprudência , Humanos , Pessoal de Laboratório/economia , Pessoal de Laboratório/psicologia , Má Conduta Profissional/ética , Política Pública , Setor Público/ética , Publicações/economia , Publicações/ética , Publicações/legislação & jurisprudência , Publicações/normas , Ciência/economia , Ciência/ética , Confiança , Estados Unidos
12.
Nature ; 580(7802): 232-234, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32269340

RESUMO

Environmental change is rapidly accelerating, and many species will need to adapt to survive1. Ensuring that protected areas cover populations across a broad range of environmental conditions could safeguard the processes that lead to such adaptations1-3. However, international conservation policies have largely neglected these considerations when setting targets for the expansion of protected areas4. Here we show that-of 19,937 vertebrate species globally5-8-the representation of environmental conditions across their habitats in protected areas (hereafter, niche representation) is inadequate for 4,836 (93.1%) amphibian, 8,653 (89.5%) bird and 4,608 (90.9%) terrestrial mammal species. Expanding existing protected areas to cover these gaps would encompass 33.8% of the total land surface-exceeding the current target of 17% that has been adopted by governments. Priority locations for expanding the system of protected areas to improve niche representation occur in global biodiversity hotspots9, including Colombia, Papua New Guinea, South Africa and southwest China, as well as across most of the major land masses of the Earth. Conversely, we also show that planning for the expansion of protected areas without explicitly considering environmental conditions would marginally reduce the land area required to 30.7%, but that this would lead to inadequate niche representation for 7,798 (39.1%) species. As the governments of the world prepare to renegotiate global conservation targets, policymakers have the opportunity to help to maintain the adaptive potential of species by considering niche representation within protected areas1,2.


Assuntos
Conservação dos Recursos Naturais/legislação & jurisprudência , Ecossistema , Política Ambiental/legislação & jurisprudência , Internacionalidade , Animais , Biodiversidade , Governo Federal , Cooperação Internacional/legislação & jurisprudência , Tamanho da Amostra
13.
Artigo em Inglês | MEDLINE | ID: mdl-32168909

RESUMO

Local water governance is challenging given the significance to public health and the difficulties to manage it in a fragmented administrative system. A collaboration network is a popular governance tool in local governance to cope with functional fragmentation problems and institutional collective action (ICA) dilemmas. Empirical works are needed to examine the outcomes of such governance networks, especially in the context of environmental governance. With fuzzy-set qualitative comparative analysis (fsQCA), this article seeks to evaluate the outcomes of collaboration networks by investigating the influence of network structures on local water governance performance in China. Based on empirical analyses on a dataset of twenty local water governance networks implementing the Water Ecological Civilization Pilot Project in China, the findings suggest that a high overall bridging and bonding of social capital and a low network density are important determinants of effective collaboration networks. This study has policy implications for the design of local collaboration networks in facilitating effective environmental governance.


Assuntos
Conservação dos Recursos Naturais/legislação & jurisprudência , Política Ambiental/legislação & jurisprudência , Água , China , Governo , Projetos Piloto , Capital Social
18.
Nature ; 579(7800): 544-548, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32214266

RESUMO

Observations show robust near-surface trends in Southern Hemisphere tropospheric circulation towards the end of the twentieth century, including a poleward shift in the mid-latitude jet1,2, a positive trend in the Southern Annular Mode1,3-6 and an expansion of the Hadley cell7,8. It has been established that these trends were driven by ozone depletion in the Antarctic stratosphere due to emissions of ozone-depleting substances9-11. Here we show that these widely reported circulation trends paused, or slightly reversed, around the year 2000. Using a pattern-based detection and attribution analysis of atmospheric zonal wind, we show that the pause in circulation trends is forced by human activities, and has not occurred owing only to internal or natural variability of the climate system. Furthermore, we demonstrate that stratospheric ozone recovery, resulting from the Montreal Protocol, is the key driver of the pause. Because pre-2000 circulation trends have affected precipitation12-14, and potentially ocean circulation and salinity15-17, we anticipate that a pause in these trends will have wider impacts on the Earth system. Signatures of the effects of the Montreal Protocol and the associated stratospheric ozone recovery might therefore manifest, or have already manifested, in other aspects of the Earth system.


Assuntos
Atmosfera/química , Política Ambiental/legislação & jurisprudência , Cooperação Internacional/legislação & jurisprudência , Ozônio/análise , Vento , Regiões Antárticas , Atividades Humanas/legislação & jurisprudência , Oceanos e Mares , Chuva , Salinidade , Movimentos da Água
19.
Artigo em Inglês | MEDLINE | ID: mdl-32102174

RESUMO

A current and universal challenge, particularly in developing nations, is the establishment of effective environmental regulation policies that protect the ecological environment without adversely affecting the international competitiveness of the domestic manufacturing industry. To deal with this dilemma, this study investigates the export competitiveness of China's manufacturing industry from the viewpoint of export value added. The Porter hypothesis is applied for an empirical investigation of the effect of environmental regulation on export competitiveness and to determine the presence of intra-industry heterogeneity. Furthermore, this study seeks to understand the mechanisms through which environmental regulation affects export competitiveness by exploring the two main approaches to technological innovation. The findings reveal that environmental regulation has a promotion effect of approximately 2% on the export competitiveness of China's manufacturing industry; however, this effect is non-linear and displays a "U-shaped" tendency, indicating that certain prerequisites must be fulfilled to validate the Porter hypothesis. In addition, the effect of environmental regulation displays significant intra-industry heterogeneity, which is evident primarily in heavily polluting sub-industries and to a lesser extent in moderately polluting sub-industries but insignificant in lightly polluting sub-industries. Environmental regulation also differs significantly in the mechanisms through which it affects different approaches to technological innovation. Independent research and development is affected by environmental regulation through the compliance cost effect, which limits export competitiveness, while technology introduction is affected by the innovation offset effect, which favors export competitiveness. These findings offer political implications for the sustainable development of the ecological environment and foreign trade.


Assuntos
Comércio , Comportamento Competitivo , Política Ambiental , Invenções , Indústria Manufatureira , Tecnologia , China , Pesquisa Empírica , Política Ambiental/legislação & jurisprudência , Poluição Ambiental/prevenção & controle
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA