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2.
J Environ Manage ; 289: 112551, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33865025

RESUMO

Life cycle assessment and kinetic modeling were used to elucidate the impact of thermal intensification (TI) on resource consumption and the techno-economic feasibility of a Fenton process at laboratory scale. Increasing temperature from 25 to 55 °C lowers treatment time (96.5%) and electricity use (67.8%) due to the positive impact of temperature on the reaction rate; however, beyond 50 °C no significant diminution in energy use, emissions, and operating cost was observed. The environmental footprint of the process is linked with energy use, operating pH, and the electricity share of the country; nevertheless, the impact of transport and infrastructure materials was lower. At 55 °C and pH of 2.8, emissions of precursors of freshwater and marine eutrophication, particulate matter formation, and ionizing radiation were reduced more than half; besides, in most of the midpoint categories, pondered by the ReCiPe-2016 method, emissions were lowered ca. 43.3%. The endpoint categories human health, ecosystem quality, and resource availability had a significant decline in disability-adjusted life years (46.0%), time-integrated species loss (42.0%), and surplus cost (33.1%). Harnessing the energy present in the wastewater itself decreased 41.9% global warming potential (GWP), but the use of steam for heating raised it 718.8%. In countries where electricity generation is dependent on fossil fuels, GWP could increase (2.0-20.0%) whereas GWP would decrease (8.8-9.4%) when renewable energy sources dominate. Operating at 55 °C and pH of 5.5 rose the reaction time (1835.5%), GWP (29.3%), particulate matter formation (44.3%), terrestrial acidification (21.8%), marine (48.9%), and freshwater eutrophication (66.7%). TI of Fenton processes could increase their treatment capacity with a small reduction in the quality of the effluent; furthermore, they can be made affordable for low-to-medium scale industries in emerging economies due to decreased resources consumption and emissions, leading to a lower treatment cost (US$0.49/m3).


Assuntos
Ecossistema , Combustíveis Fósseis , Eutrofização , Aquecimento Global , Humanos , Águas Residuárias
3.
Environ Sci Technol ; 55(8): 5258-5271, 2021 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-33709686

RESUMO

Earlier research in this journal suggests that nuclear power systems have prevented 1.84 million air pollution-related deaths from 1971 to 2009 and could save an additional 7 million deaths by 2050. Building on that work, we adopt a broader lens that looks at renewable energy and nuclear power as well as a greater range of energy pathways. We examine via 10 hypothetical scenarios and two time frames the varying impact of different technology configurations on the full potential of avoided carbon emissions and avoided mortality across China, the European Union, India, and the United States. From 2000 to 2020, we estimate the substitution of fossil fuels by nuclear power has saved as many as 42 million lives. Similarly, substituting fossil fuels with hydropower has saved 42.1 million lives (slightly more than that for nuclear power). Finally, other forms of renewable energy have saved another 38 million lives . We project that from 2021 to 2040, nuclear power could save an additional 46.1 million lives and displace 1198 GtCO2; hydropower could save a further 46.2 million lives and displace 1281.47 GtCO2; substituting fossil fuels with other renewable energy could similarly save an additional 41.2 million lives as well as displace over 1250 GtCO2. We offer a critical thought experiment on just how much potential low-carbon options have to provide positive externalities compared to fossil fuels.


Assuntos
Dióxido de Carbono , Carbono , Carbono/análise , Dióxido de Carbono/análise , China , Combustíveis Fósseis , Índia , Energia Renovável , Estados Unidos
4.
Environ Sci Technol ; 55(8): 4183-4189, 2021 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-33666422

RESUMO

Energy supply limits development through fuel constraints and climatic effects. Production of renewable energy is a central pillar of sustainability but will need to play an increasingly important role in energy generation in order to mitigate fossil-fuel based greenhouse-gas emissions. Global freshwaters represent a vast reservoir of biomass and biogenic CH4. Here we demonstrate the great potential for the optimized use of this nonfossil carbon as a source of energy that is replenishable within a human lifetime. The feasibility of up-scaled adsorption-driven technologies to capture and refine aqueous CH4 still awaits verification, yet recent estimates of global freshwater CH4 production imply that the worldwide energy demand could be satisfied by using the "biofuel" building up in lakes and wetlands. Biogenic CH4 is mostly generated from biomass produced through atmospheric CO2 uptake. Its exploitation in freshwaters can thus secure large amounts of carbon-neutral energy, helping to sustain the planetary equilibrium.


Assuntos
Gases de Efeito Estufa , Metano , Dióxido de Carbono/análise , Combustíveis Fósseis , Água Doce , Humanos , Metano/análise , Áreas Alagadas
5.
Environ Pollut ; 275: 116615, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33571855

RESUMO

To prevent spreads of Coronavirus disease-2019 (COVID-19), China adopted the lockdown measures in late January 2020, providing a platform to study the response of air quality and atmospheric chemical and physical properties to strict reduced emissions. In this study, the continuous measurements of aerosol light absorption were conducted in Nanjing, east China, from January 3 to March 31, 2020. Our results showed that the contribution of black carbon (BC) to light absorption at the different wavelengths was more than 75% and the rest light absorption was contributed by brown carbon (BrC), which was mainly originated from primary emissions. Secondary BrC absorption, which was mainly produced by photochemical oxidation, constituted a minor fraction (2-7%) of the total absorption. Compared with the sampling in the pre-lockdown, the significant decreases of BC (43%) and secondary BrC absorption (31%) were found during the lockdown period, resulting in a substantial decrease of solar energy absorbance by 36% on a local scale. The control measures also changed the diurnal variations of light absorption. Due to the reduced emissions, the relative fraction of fossil fuel to BC also dropped from 78% in the pre-lockdown to 71% in the lockdown. The concentrations of BC, PM2.5 and NO2 decreased 1.1 µg m-3, 33 µg m-3 and 9.1 ppb whereas O3 concentration increased 9.0 ppb during the COVID-19 lockdown period. The decreased concentrations of BC, PM2.5 and NO2 were mainly contributed by both emission reduction (51-64%) and meteorological conditions (36-49%). Our results highlighted that the balance of control measures in alleviation of particulate matter (PM) and O3 pollution, and meteorology should be seriously considered for improvement of air quality in this urban city of China.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Aerossóis/análise , Poluentes Atmosféricos/análise , Poluição do Ar/análise , China , Cidades , Controle de Doenças Transmissíveis , Monitoramento Ambiental , Combustíveis Fósseis/análise , Humanos , Material Particulado/análise
6.
Environ Res ; 195: 110754, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33577774

RESUMO

The burning of fossil fuels - especially coal, petrol, and diesel - is a major source of airborne fine particulate matter (PM2.5), and a key contributor to the global burden of mortality and disease. Previous risk assessments have examined the health response to total PM2.5, not just PM2.5 from fossil fuel combustion, and have used a concentration-response function with limited support from the literature and data at both high and low concentrations. This assessment examines mortality associated with PM2.5 from only fossil fuel combustion, making use of a recent meta-analysis of newer studies with a wider range of exposure. We also estimated mortality due to lower respiratory infections (LRI) among children under the age of five in the Americas and Europe, regions for which we have reliable data on the relative risk of this health outcome from PM2.5 exposure. We used the chemical transport model GEOS-Chem to estimate global exposure levels to fossil-fuel related PM2.5 in 2012. Relative risks of mortality were modeled using functions that link long-term exposure to PM2.5 and mortality, incorporating nonlinearity in the concentration response. We estimate a global total of 10.2 (95% CI: -47.1 to 17.0) million premature deaths annually attributable to the fossil-fuel component of PM2.5. The greatest mortality impact is estimated over regions with substantial fossil fuel related PM2.5, notably China (3.9 million), India (2.5 million) and parts of eastern US, Europe and Southeast Asia. The estimate for China predates substantial decline in fossil fuel emissions and decreases to 2.4 million premature deaths due to 43.7% reduction in fossil fuel PM2.5 from 2012 to 2018 bringing the global total to 8.7 (95% CI: -1.8 to 14.0) million premature deaths. We also estimated excess annual deaths due to LRI in children (0-4 years old) of 876 in North America, 747 in South America, and 605 in Europe. This study demonstrates that the fossil fuel component of PM2.5 contributes a large mortality burden. The steeper concentration-response function slope at lower concentrations leads to larger estimates than previously found in Europe and North America, and the slower drop-off in slope at higher concentrations results in larger estimates in Asia. Fossil fuel combustion can be more readily controlled than other sources and precursors of PM2.5 such as dust or wildfire smoke, so this is a clear message to policymakers and stakeholders to further incentivize a shift to clean sources of energy.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Ásia , Criança , Pré-Escolar , China , Exposição Ambiental , Europa (Continente) , Combustíveis Fósseis , Humanos , Índia , Lactente , Recém-Nascido , América do Norte , Material Particulado/análise , Material Particulado/toxicidade
7.
Environ Sci Pollut Res Int ; 28(13): 15607-15626, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33538968

RESUMO

One of the main problems facing our planetary bodies is unexpected and sudden climate change due to continuously increasing global energy demand, which currently is being met by fossil fuels. Hydrogen is considered as one of the major energy solutions of the twenty-first century, capable of meeting future energy needs. Being 61a zero-emission fuel, it could reduce environmental impacts and craft novel energy opportunities. Hydrogen through fuel cells can be used in transport and distributed heating, as well as in energy storage systems. The transition from fossil-based fuels to hydrogen requires intensive research to overcome scientific and socio-economic barriers. The purpose of this paper is to reflect the current state, related issues, and projection of hydrogen and fuel elements within the conceptual framework of 61a future sustainable energy vision. An attempt has been made to compile in this paper the past hydrogen-related technologies, present challenges, and role of hydrogen in the future.


Assuntos
Combustíveis Fósseis , Hidrogênio , Mudança Climática , Energia Renovável , Tecnologia
8.
Environ Pollut ; 276: 116645, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33592443

RESUMO

Black Carbon (BC) is an absorbing aerosol which has significant impact on the Earth - Atmosphere radiation balance and hence on climate. The variation of BC mass concentration and contribution of fossil fuel and biomass burning have been investigated over the Indian ocean sector of the Southern Ocean during austral summer. BC mass was in the range of 300-500 ng m-3 between 23.3oS to 24.5oS followed by decrease in BC to 150 ng m-3 as moving to higher southern latitudes till 41oS latitude. An increase in BC mass from 250 to 450 ng m-3 was found between 41 and 50oS due to trap of air masses by cyclonic wind and transport of aerosols from the southern part of African and eastern Madagascar regions. Higher BC concentration (250-350 ng m-3) was observed in the latitude range of 57-60oS which can be attributed to convergence of north-westerly and south-easterly winds. The dominant contributor to BC was fossil fuel, which was > 80% during half of the total observations, while > 20% biomass burning contributed to one fifth of observations. The coastal Antarctic region showed higher BC mass concentration with mixed type of contributions of biomass and fossil fuel. Such accumulation of BC near the Antarctic coast can have a crucial impact on the sea-ice albedo which significantly affect the Antarctic climate system locally and global climate in general.


Assuntos
Poluentes Atmosféricos , Combustíveis Fósseis , Aerossóis/análise , Poluentes Atmosféricos/análise , Regiões Antárticas , Biomassa , Carbono/análise , Monitoramento Ambiental , Oceano Índico
10.
Mar Pollut Bull ; 164: 112007, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33485021

RESUMO

Stable isotopes (δ13C and δ15N) in marine ecosystem are useful proxies for environmental record. In this study, a time-series analysis of δ13C and δ15N in two black coral samples collected from off-shore and near-shore environment was performed to investigate variations in climate and environment changes over the last 110 years. The results showed a decreasing trend of δ13C in both samples, implying an increase of fossil fuel consumption in modern age - the Suess effect. Meanwhile, a difference in δ15N between the offshore and nearshore black coral samples can be attributed to atmospheric transport of natural terrigenous source input and local anthropogenic activities. This study demonstrates that black coral has advantages as an environmental proxy compared with other traditional ones, and suggests that δ13C and δ15N in black coral can be used as new proxy indicators for climate changes related to anthropogenic activities.


Assuntos
Antozoários , Animais , Isótopos de Carbono/análise , Ecossistema , Combustíveis Fósseis , Isótopos , Isótopos de Nitrogênio/análise
11.
Environ Sci Pollut Res Int ; 28(12): 14253-14270, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33515405

RESUMO

The textile industry is a large source of pollution due to the production of raw materials (natural and synthetic fibers), preparation and finishing processes, as well as due to textile waste, especially the post-consumer waste. This paper is an attempt to change the perception concerning such waste. In the context of circular economy, textile waste has to be conceived as a source for carbon and energy. A new attitude is compulsory due to the increase of post-consumer waste quantity since the volume of textile consumption has lately increased. Fast fashion cycle and cheaper textile products having a shorter lifetime led to an increase of the quantity of post-consumer textile waste. Demands for pollution reduction generated the concern to upcycle the textile waste in order to recover, at least partially, the materials as well as the energy consumed for their manufacture, reducing accordingly the carbon and water footprints of these products,. The scarcity of raw materials and of fossil fuels, the high environmental impact of the simple disposal of waste, imposed a new policy regarding the transformation of the linear economy which characterizes today's textile industry into a circular one, leading to a lower environmental impact. This involves the valorization of post-consumer waste by recycling or at least by a partial recovery of the materials and energy spent for the manufacture of these products. A good management of post-consumer textile waste is mandatory for attaining a zero waste target. Some good practices in the field are presented by this paper.


Assuntos
Reciclagem , Gerenciamento de Resíduos , Combustíveis Fósseis , Indústria Têxtil , Têxteis
12.
Environ Sci Pollut Res Int ; 28(14): 17319-17330, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33394416

RESUMO

The accelerated urbanization in China was already coupled with a steadily increasing demand for energy usage. The present study major aim was to determine the asymmetric influence of urbanization, energy utilization, fossil fuel energy and CO2 emission on economic progress in China by using an annual time series data varies from 1975 to 2017. Stationarity amid variables was verified by applying the unit root tests, while non-linear autoregressive distributed lag (NARDL) bounds testing model was used to examine the asymmetric impacts on variables with short- and long-run dynamics. Outcomes revealed that via short-run estimates, the negative shocks of energy usage cause significantly to increase the economic efficiency, but positive shocks of energy utilization display the adverse linkage with the economic progress. Similarly, the negative shocks of GDP per capita growth demonstrate a substantial upsurge in the economic progress, and the positive shocks establish the adverse influence towards economic growth. Further, the outcomes of short-run dynamics also exposed the negative shocks of urbanization significantly affected the economic growth, but positive shocks exposed the adversative influence on economic growth. The outcomes display that fossil fuel energy consumption showed a constructive impact to economic progress, and additionally, the variable CO2 emission also uncovered a positive shocks having significant impact on economic progress. Furthermore, the outcomes of long-run analysis express that energy utilization has negative and positive shocks that expose the adverse influence on economic progress of China. GDP per capita growth exposed the constructive influence on the economic growth in both shocks. The negative and positive shocks of urbanization demonstrate a noteworthy influence on economic growth. The variable fossil fuel energy consumption also exposed an optimistic influence on economic progress, and finally the influence of CO2 emission on economic growth is insignificant as the results exposed. The reducing carbon alteration target aims to be reached for China, and in the next several decades, it will encourage the green energy options in order to decrease carbon dioxide emission to avoid environmental pollution by raising its energy intensity.


Assuntos
Dióxido de Carbono , Urbanização , Dióxido de Carbono/análise , China , Desenvolvimento Econômico , Combustíveis Fósseis
13.
Environ Sci Pollut Res Int ; 28(14): 17158-17169, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33394432

RESUMO

More than any other nations, the crude oil-exporting countries and especially the Organization of the Petroleum Exporting Countries (OPEC) are likely to experience a more difficult energy-transitioning regime because of the economies' high dependence on crude oil revenue. By using the Pooled Mean Group (PMG) Autoregressive Distributed Lag Models (ARDL) approach, this study examines the impact of the energy transition albeit from conventional to clean energy on carbon emissions in 11 members of the OPEC. While engaging the aforementioned objective, the study further examined the validity of the Environmental Kuznets Curve (EKC) hypothesis amidst urbanization drive among the countries. The result from the long-run estimates shows that fossil fuel utilization exerts a positively significant on environmental degradation in the selected countries, while the observed negative impact of renewable energy utilization and urbanization on carbon dioxide emission (CO2) was insignificant in both the short and long run. The implication is that the current energy transition policy of the OPEC states is not sufficient at driving the states' environmental sustainability agenda. In addition, the EKC was not valid in the panel of the OPEC countries for the period of study, rather a U-shaped relation is established between income level and environmental degradation. Thus, this further posits that there is a setback in the push for environmental quality especially when there is an improvement in economic well-being through income growth in the OPEC states. Moreover, findings from the panel causality test show that there is no causality running from both fossil fuel and renewable energy consumption to the income level among the countries. On the contrary, a uni-directional causality was obtained from income level to renewable energy consumption, while urbanization strongly Granger causes fossil fuel use and CO2 emissions among the countries. As such, it is concluded that energy conservation policies can be implemented to reduce extreme dependence on fossil fuel use with little or no detrimental consequences, thus positioning the countries for economic prosperity in a sustainable environment.


Assuntos
Desenvolvimento Econômico , Petróleo , Dióxido de Carbono/análise , Combustíveis Fósseis , Energia Renovável , Urbanização
14.
Nature ; 589(7843): 554-561, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33505037

RESUMO

Historically, human uses of land have transformed and fragmented ecosystems1,2, degraded biodiversity3,4, disrupted carbon and nitrogen cycles5,6 and added prodigious quantities of greenhouse gases (GHGs) to the atmosphere7,8. However, in contrast to fossil-fuel carbon dioxide (CO2) emissions, trends and drivers of GHG emissions from land management and land-use change (together referred to as 'land-use emissions') have not been as comprehensively and systematically assessed. Here we present country-, process-, GHG- and product-specific inventories of global land-use emissions from 1961 to 2017, we decompose key demographic, economic and technical drivers of emissions and we assess the uncertainties and the sensitivity of results to different accounting assumptions. Despite steady increases in population (+144 per cent) and agricultural production per capita (+58 per cent), as well as smaller increases in emissions per land area used (+8 per cent), decreases in land required per unit of agricultural production (-70 per cent) kept global annual land-use emissions relatively constant at about 11 gigatonnes CO2-equivalent until 2001. After 2001, driven by rising emissions per land area, emissions increased by 2.4 gigatonnes CO2-equivalent per decade to 14.6 gigatonnes CO2-equivalent in 2017 (about 25 per cent of total anthropogenic GHG emissions). Although emissions intensity decreased in all regions, large differences across regions persist over time. The three highest-emitting regions (Latin America, Southeast Asia and sub-Saharan Africa) dominate global emissions growth from 1961 to 2017, driven by rapid and extensive growth of agricultural production and related land-use change. In addition, disproportionate emissions are related to certain products: beef and a few other red meats supply only 1 per cent of calories worldwide, but account for 25 per cent of all land-use emissions. Even where land-use change emissions are negligible or negative, total per capita CO2-equivalent land-use emissions remain near 0.5 tonnes per capita, suggesting the current frontier of mitigation efforts. Our results are consistent with existing knowledge-for example, on the role of population and economic growth and dietary choice-but provide additional insight into regional and sectoral trends.


Assuntos
Agricultura/estatística & dados numéricos , Dióxido de Carbono/análise , Combustíveis Fósseis , Atividades Humanas , Internacionalidade , Metano/análise , Óxido Nitroso/análise , África ao Sul do Saara , Animais , Ásia Sudeste , Produtos Agrícolas/provisão & distribução , Grão Comestível/provisão & distribução , Mapeamento Geográfico , História do Século XX , História do Século XXI , América Latina , Esterco , Oryza , Carne Vermelha/provisão & distribução , Solo , Desenvolvimento Sustentável/tendências , Madeira
15.
Sci Rep ; 10(1): 22355, 2020 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-33339883

RESUMO

Global warming has become a serious issue nowadays as the trend of CO2 emission is increasing by years. In Malaysia, the electricity and energy sector contributed a significant amount to the nation's CO2 emission due to fossil fuel use. Many research works have been carried out to mitigate this issue, including carbon capture and utilization (CCUS) technology and biological carbon fixation by microalgae. This study makes a preliminary effort to screen native microalgae species in the Malaysian coal-fired power plant's surrounding towards carbon fixation ability. Three dominant species, including Nannochloropsis sp., Tetraselmis sp., and Isochrysis sp. were identified and tested in the laboratory under ambient and pure CO2 condition to assess their growth and CO2 fixation ability. The results indicate Isochrysis sp. as the superior carbon fixer against other species. In continuation, the optimization study using Response Surface Methodology (RSM) was carried out to optimize the operating conditions of Isochrysis sp. using a customized lab-scale photobioreactor under simulated flue gas exposure. This species was further acclimatized and tested under actual flue gas generated by the power plant. Isochrysis sp. had shown its capability as a carbon fixer with CO2 fixation rate of 0.35 gCO2/L day under actual coal-fired flue gas exposure after cycles of acclimatization phase. This work is the first to demonstrate indigenous microalgae species' ability as a carbon fixer under Malaysian coal-fired flue gas exposure. Thus, the findings shall be useful in exploring the microalgae potential as a biological agent for carbon emission mitigation from power plants more sustainably.


Assuntos
Ciclo do Carbono/fisiologia , Dióxido de Carbono/efeitos adversos , Carvão Mineral/efeitos adversos , Microalgas/metabolismo , Biomassa , Carbono/metabolismo , Ciclo do Carbono/genética , Dióxido de Carbono/química , Combustíveis Fósseis/efeitos adversos , Aquecimento Global , Humanos , Microalgas/química , Microalgas/genética , Fotobiorreatores , Centrais Elétricas
17.
PLoS One ; 15(10): e0239634, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33021990

RESUMO

In recent years, the environmental problems caused by excessive carbon emissions from energy sources have become increasingly serious, which not only aggravates the climate change caused by the greenhouse effect but also seriously restricts the sustainable development of Chinese economy. An attempt is made in this paper to use energy consumption method and input-output method to study the carbon emission structure of China's energy system and industry in 2015 from two perspectives, namely China's energy supply side and energy demand side, by taking into account the two factors of energy invest in gross capital formation and export. The results show that neglecting these two factors will lead to underestimation of intermediate use carbon emissions and overestimation of final use carbon emissions. On energy supply side, the carbon emission structure of China's energy system is still dominated by high-carbon energy (raw coal, coke, diesel, and fuel oil, etc.), accounting for more than 70% of total energy carbon emissions; on the contrary, the natural gas such as clean energy accounts for only 3.45% of total energy carbon emissions, indicating that the energy consumption structure optimization and emission reduction gap of China's energy supply side are still substantial. On energy demand side, the final use (direct consumption by residents and government) produces less carbon emissions, while the intermediate use (production by enterprises) produces more than 90% of the total energy carbon emissions. Fossil energy, power sector, heavy industry, chemical industry, and transportation belong to industries with larger carbon emissions and lower carbon emission efficiency, while agriculture, construction, light industry, and service belong to industries with fewer carbon emissions and higher carbon emission efficiency. This means that the optimization of industrial structure is conducive to slowing down the growth of energy carbon emissions on the demand side.


Assuntos
Pegada de Carbono/economia , Desenvolvimento Econômico , Combustíveis Fósseis , Aquecimento Global/economia , Carbono/análise , China , Mudança Climática/economia , Carvão Mineral/economia , Fontes Geradoras de Energia/economia , Poluição Ambiental/economia , Poluição Ambiental/prevenção & controle , Combustíveis Fósseis/economia , Aquecimento Global/prevenção & controle , Efeito Estufa/economia , Efeito Estufa/prevenção & controle , Humanos , Indústrias/economia , Investimentos em Saúde
18.
Nat Commun ; 11(1): 5172, 2020 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-33057164

RESUMO

The COVID-19 pandemic is impacting human activities, and in turn energy use and carbon dioxide (CO2) emissions. Here we present daily estimates of country-level CO2 emissions for different sectors based on near-real-time activity data. The key result is an abrupt 8.8% decrease in global CO2 emissions (-1551 Mt CO2) in the first half of 2020 compared to the same period in 2019. The magnitude of this decrease is larger than during previous economic downturns or World War II. The timing of emissions decreases corresponds to lockdown measures in each country. By July 1st, the pandemic's effects on global emissions diminished as lockdown restrictions relaxed and some economic activities restarted, especially in China and several European countries, but substantial differences persist between countries, with continuing emission declines in the U.S. where coronavirus cases are still increasing substantially.


Assuntos
Poluentes Atmosféricos/análise , Dióxido de Carbono/análise , Infecções por Coronavirus/epidemiologia , Pneumonia Viral/epidemiologia , Poluentes Atmosféricos/economia , Betacoronavirus , Dióxido de Carbono/economia , Infecções por Coronavirus/economia , Infecções por Coronavirus/prevenção & controle , Monitoramento Ambiental , Combustíveis Fósseis/análise , Combustíveis Fósseis/economia , Humanos , Indústrias/economia , Dióxido de Nitrogênio/análise , Dióxido de Nitrogênio/economia , Pandemias/economia , Pandemias/prevenção & controle , Pneumonia Viral/economia , Pneumonia Viral/prevenção & controle
19.
Sci Rep ; 10(1): 18688, 2020 10 29.
Artigo em Inglês | MEDLINE | ID: mdl-33122844

RESUMO

The COVID-19 pandemic caused drastic reductions in carbon dioxide (CO2) emissions, but due to its large atmospheric reservoir and long lifetime, no detectable signal has been observed in the atmospheric CO2 growth rate. Using the variabilities in CO2 (ΔCO2) and methane (ΔCH4) observed at Hateruma Island, Japan during 1997-2020, we show a traceable CO2 emission reduction in China during February-March 2020. The monitoring station at Hateruma Island observes the outflow of Chinese emissions during winter and spring. A systematic increase in the ΔCO2/ΔCH4 ratio, governed by synoptic wind variability, well corroborated the increase in China's fossil-fuel CO2 (FFCO2) emissions during 1997-2019. However, the ΔCO2/ΔCH4 ratios showed significant decreases of 29 ± 11 and 16 ± 11 mol mol-1 in February and March 2020, respectively, relative to the 2011-2019 average of 131 ± 11 mol mol-1. By projecting these observed ΔCO2/ΔCH4 ratios on transport model simulations, we estimated reductions of 32 ± 12% and 19 ± 15% in the FFCO2 emissions in China for February and March 2020, respectively, compared to the expected emissions. Our data are consistent with the abrupt decrease in the economic activity in February, a slight recovery in March, and return to normal in April, which was calculated based on the COVID-19 lockdowns and mobility restriction datasets.


Assuntos
Dióxido de Carbono/análise , Infecções por Coronavirus/epidemiologia , Combustíveis Fósseis/estatística & dados numéricos , Efeito Estufa/estatística & dados numéricos , Pneumonia Viral/epidemiologia , Atmosfera/química , China , Infecções por Coronavirus/economia , Humanos , Japão , Metano/análise , Pandemias/economia , Pneumonia Viral/economia
20.
Chemosphere ; 254: 126849, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32957276

RESUMO

Black carbon (BC), which is a by-product with incomplete combustion of carbonaceous materials, can be used as an indicator of combustion emissions and is an important climate forcer. In this study, a spatial-temporal synthesis of BC aerosols and the affecting factors was conducted in urban Beijing. As observed, BC showed a spatial pattern with high concentration in south and low in north. BC concentration evidently decreased by approximately 61% between 2005 and 2017. From 2015 to 2017, the mass ratio of BC/PM2.5 dropped by 28%, which suggested a more efficient effect of control measures to BC than PM2.5. The BC/CO ratio dropped by 22%, which indicated the decreasing emission from fossil fuel sources. With regard to BC loading, the spectral dependence of absorption aerosol exhibited significant seasonal variations. High absorption Ångström exponent (α) was observed during heating season, which reflected the increasing contribution of brown carbon (BrC) to light absorption. Backward trajectory analysis showed that the levels of BC and PM2.5 were high in Cluster-South and Cluster-West. BrC absorption was high in Cluster-West, Cluster-Northwest and Cluster-Northeast, due to the biomass and coal burning for domestic heating and aging processes on a regional scale. The effects of emission control and transport variability on pollutant variation were estimated on the basis of the cluster analysis. Results indicated that the effect of emission reduction was the major reason for the decrease of BC from 2015 to 2017, which resulted in a 34% reduction of BC concentration. Meanwhile, transport variability caused a 15% reduction.


Assuntos
Aerossóis/química , Poluentes Atmosféricos/análise , Combustíveis Fósseis , Fuligem/análise , Aerossóis/análise , Pequim , Clima , Monitoramento Ambiental/métodos , Combustíveis Fósseis/análise , Meteorologia , Estações do Ano , Análise Espaço-Temporal , Emissões de Veículos/análise
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