Severe haze in northern China: A synergy of anthropogenic emissions and atmospheric processes

Proceedings of the National Academy of Sciences, Journal Year: 2019, Volume and Issue: 116(18), P. 8657 - 8666

Published: April 15, 2019

Significance Severe haze events with large temporal/spatial coverages have occurred frequently in wintertime northern China. These extremes result from a complex interplay between emissions and atmospheric processes provide unique scientific platform to gain insights into many aspects of the relevant chemistry physics. Here we synthesize recent progress understanding severe formation In particular, highlight that improved emission sources, physical/chemical during evolution, interactions meteorological/climatic changes are necessary unravel causes, mechanisms, trends for pollution. This viewpoint established on basis sound science is critical improving prediction/forecast, formulating effective regulatory policies by decision makers, raising public awareness environmental protection.

Language: Английский

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Substantial convection and precipitation enhancements by ultrafineaerosol particles

Science, Journal Year: 2018, Volume and Issue: 359(6374), P. 411 - 418

Published: Jan. 25, 2018

Up with ultrafine aerosol particles Ultrafine (smaller than 50 nanometers in diameter) have been thought to be too small affect cloud formation. Fan et al. show that this is not the case. They studied effect of urban pollution transported into otherwise nearly pristine atmosphere Amazon. Condensational growth water droplets around tiny releases latent heat, thereby intensifying atmospheric convection. Thus, anthropogenic may exert a more important influence on formation processes previously believed. Science , issue p. 411

Language: Английский

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Mixed-Phase Clouds: Progress and Challenges

Meteorological Monographs, Journal Year: 2017, Volume and Issue: 58, P. 5.1 - 5.50

Published: Jan. 1, 2017

Mixed-phase clouds represent a three-phase colloidal system consisting of water vapor, ice particles, and coexisting supercooled liquid droplets. are ubiquitous in the troposphere, occurring at all latitudes from polar regions to tropics. Because their widespread nature, mixed-phase processes play critical roles life cycle clouds, precipitation formation, cloud electrification, radiative energy balance on both regional global scales. Yet, spite many decades observations theoretical studies, our knowledge understanding remains incomplete. notoriously difficult numerical weather prediction climate models, description physics still presents complicated challenges. In this chapter, current status obtained studies observations, is reviewed. Recent progress, along with discussion problems gaps environment summarized. Specific steps improve role proposed.

Language: Английский

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Increased rainfall volume from future convective storms in the US

Nature Climate Change, Journal Year: 2017, Volume and Issue: 7(12), P. 880 - 884

Published: Nov. 17, 2017

Language: Английский

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East Asian Study of Tropospheric Aerosols and their Impact on Regional Clouds, Precipitation, and Climate (EAST‐AIR_CPC)

Journal of Geophysical Research Atmospheres, Journal Year: 2019, Volume and Issue: 124(23), P. 13026 - 13054

Published: Oct. 23, 2019

Abstract Aerosols have significant and complex impacts on regional climate in East Asia. Cloud‐aerosol‐precipitation interactions (CAPI) remain most challenging studies. The quantitative understanding of CAPI requires good knowledge aerosols, ranging from their formation, composition, transport, radiative, hygroscopic, microphysical properties. A comprehensive review is presented here centered the based chiefly, but not limited to, publications special section named EAST‐AIRcpc concerning (1) observations aerosol loading properties, (2) relationships between aerosols meteorological variables affecting CAPI, (3) mechanisms behind (4) quantification impact climate. Heavy Asia has radiative effects by reducing surface radiation, increasing air temperature, lowering boundary layer height. key factor absorption, which particularly strong central China. This absorption can a wide range such as creating an imbalance forcing at top bottom atmosphere, leading to inconsistent retrievals cloud space‐borne ground‐based instruments. Aerosol delay or suppress initiation development convective clouds whose microphysics be further altered effect aerosols. For same thickness, likelihood precipitation influenced aerosols: suppressing light rain enhancing heavy rain, delaying intensifying thunderstorms, onset isolated showers parts Rainfall become more inhomogeneous extreme heavily polluted urban regions.

Language: Английский

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100 Years of Research on Mesoscale Convective Systems

Meteorological Monographs, Journal Year: 2018, Volume and Issue: 59, P. 17.1 - 17.54

Published: Jan. 1, 2018

Abstract When cumulonimbus clouds aggregate, developing into a single entity with precipitation covering horizontal scale of hundreds kilometers, they are called mesoscale convective systems (MCSs). They account for much Earth’s precipitation, generate severe weather events and flooding, produce prodigious cirriform anvil clouds, affect the evolution larger-scale circulation. Understanding inner workings MCSs has resulted from developments in observational technology modeling. Time–space conversion ordinary surface upper-air observations provided early insight MCSs, but deeper understanding followed field campaigns using increasingly sophisticated radars, better aircraft instrumentation, an ever-widening range satellite instruments, especially satellite-borne radars. High-resolution modeling theoretical insights have shown that aggregated induce circulation consisting air overturning on larger than individual up- downdrafts. These layers can be kilometers deep decoupled boundary layer elevated MCSs. Cooling lower troposphere heating aloft characterize stratiform regions As result, long-lived large top-heavy profile generates potential vorticity midlevels, thus influencing within which occur. Global data show varying structure, depending prevailing large-scale topography. patterns likely to change global warming. In addition, environmental pollution affects MCS structure dynamics subtly. Feedbacks therefore need included or parameterized climate models.

Language: Английский

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Forests, atmospheric water and an uncertain future: the new biology of the global water cycle

Forest Ecosystems, Journal Year: 2018, Volume and Issue: 5(1)

Published: March 14, 2018

Theory and evidence indicate that trees other vegetation influence the atmospheric water-cycle in various ways. These influences are more important, complex, poorly characterised than is widely realised. While there little doubt changes tree cover will impact water-cycle, wider consequences remain difficult to predict as underlying relationships processes characterised. Nonetheless, forests vulnerable human activities, these linked aspects of also at risk potential large scale forest loss severe. Here, for non-specialist readers, I review our knowledge links between vegetation-cover climate with a focus on rain (precipitation). highlight advances, uncertainties research opportunities. There significant shortcomings understanding hydrological cycle its representation models. A better role tree-cover reduce some shortcomings. outline illustrate themes where advances may be found. include biology evaporation, aerosols motion, well determine monsoons diurnal precipitation cycles. novel theory—the ‘biotic pump’—suggests evaporation condensation can exert major over dynamics. This theory explains how high rainfall maintained within those continental land-masses sufficiently forested. Feedbacks many result non-linear behaviours dramatic (or gain): example, switching from wet dry local visa-versa). Much remains unknown multiple disciplines needed address this: scientists biologists have play. New ideas, methods data offer opportunities improve understanding. Expect surprises.

Language: Английский

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Description and evaluation of the tropospheric aerosol scheme in the European Centre for Medium-Range Weather Forecasts (ECMWF) Integrated Forecasting System (IFS-AER, cycle 45R1)

Geoscientific model development, Journal Year: 2019, Volume and Issue: 12(11), P. 4627 - 4659

Published: Nov. 7, 2019

Abstract. This article describes the IFS-AER aerosol module used operationally in Integrated Forecasting System (IFS) cycle 45R1, operated by European Centre for Medium-Range Weather Forecasts (ECMWF) framework of Copernicus Atmospheric Monitoring Services (CAMS). We describe different parameterizations sources, sinks, and its chemical production IFS-AER, as well how aerosols are integrated larger atmospheric composition forecasting system. The focus is on entire 45R1 code base, including some components that not operationally, which case this will be clearly specified. paper an update to Morcrette et al. (2009) described forecasts at ECMWF using 32R2 IFS. Between cycles a number source sink processes have been reviewed and/or added, notably increasing complexity IFS-AER. A greater integration with tropospheric chemistry scheme IFS has achieved sulfur nitrate production. Two new species, ammonium, also included Global budgets optical depth (AOD) fields shown, evaluation simulated particulate matter (PM) AOD against observations, showing increase skill from 40R2, CAMS interim ReAnalysis (CAMSiRA), 45R1.

Language: Английский

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Advances in air quality research – current and emerging challenges

Atmospheric chemistry and physics, Journal Year: 2022, Volume and Issue: 22(7), P. 4615 - 4703

Published: April 11, 2022

Abstract. This review provides a community's perspective on air quality research focusing mainly developments over the past decade. The article perspectives current and future challenges as well needs for selected key topics. While this paper is not an exhaustive of all areas in field quality, we have topics that feel are important from policy perspectives. After providing short historical overview, focuses improvements characterizing sources emissions pollution, new observations instrumentation, advances prediction forecasting, understanding interactions with meteorology climate, exposure health assessment, management policy. In conducting review, specific objectives were (i) to address push boundaries forward, (ii) highlight emerging prominent gaps knowledge research, (iii) make recommendations guide direction within wider community. also identifies particular importance original concept was borne at International Conference Air Quality 2020 (held online due COVID 19 restrictions during 18–26 May 2020), but incorporates landscape literature science. On pollution highlights, particular, need reduce uncertainties diffuse sources, particulate matter chemical components, shipping emissions, considering both indoor outdoor sources. There growing integrated related ground-based remote sensing instruments, including those satellites. should capitalize area low-cost sensors, while ensuring measurements which regulated by guidelines. Connecting various physical scales modelling still continual issue, cities being affected gradients local long-range transport. At same time, one allow impacts climate change longer timescale. Earth system offers considerable potential consistent framework treating processes, especially where there significant feedbacks, such aerosols, chemistry, meteorology. Assessment consider application more sophisticated, dynamic approaches predict concentrations pollutants environments. With most health, indicating urgent understand, role particle number components terms impact, turn requires improved emission inventories models predicting high-resolution distributions these metrics cities. examines how adapt above-mentioned briefly considers implications COVID-19 pandemic quality. Finally, provide support

Language: Английский

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Process Drivers, Inter-Model Spread, and the Path Forward: A Review of Amplified Arctic Warming

Frontiers in Earth Science, Journal Year: 2022, Volume and Issue: 9

Published: Feb. 9, 2022

Arctic amplification (AA) is a coupled atmosphere-sea ice-ocean process. This understanding has evolved from the early concept of AA, as consequence snow-ice line progressions, through more than century research that clarified relevant processes and driving mechanisms AA. The predictions made by modeling studies, namely fall/winter maximum, bottom-heavy structure, prominence surface albedo feedback, importance stable stratification have withstood scrutiny multi-decadal observations complex models. Yet, uncertainty in climate projections larger any other region planet, making assessment high-impact, near-term regional changes difficult or impossible. Reducing this large spread requires quantitative process understanding. manuscript aims to build such an synthesizing current knowledge AA produce set recommendations guide future research. It briefly reviews history science, summarizes observed changes, discusses approaches feedback diagnostics, assesses most feedbacks These sections culminate conceptual model fundamental physical causing collection accelerate progress towards reduced projections. Our highlights need account for local remote interactions within context annual cycle constrain projected We recommend raising priority sensitivity research, improving accuracy energy budget observations, rethinking definitions, coordinating new experiments intercomparisons, further investigating role episodic variability

Language: Английский

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