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

---

Spatio-Temporal Variations of the PM2.5/PM10 Ratios and Its Application to Air Pollution Type Classification in China

Frontiers in Environmental Science, Journal Year: 2021, Volume and Issue: 9

Published: June 14, 2021

Particulate Matter (PM) is an important indicator of the degree air pollution. The PM type and ratio coarse fine particles determine ability to affect human health atmospheric processes. Using observation data across country from 2015 2018, this study investigates distribution proportion 2.5 10 at different temporal spatial scales in mainland China; clarifies , /PM ratios interrelation; classifies dust, mixed, anthropogenic aerosol. It shows that annual average concentration decreased by 10.55 8.78 μg m −3 4 years. show obvious while seasonal variations. high winter low summer, spring, summer autumn. Differently, are highest winter, lowest spring. strong independence on implying it can provide extra information about aerosol pollution such as type. A classification method types then further proposed based probability function (PDF) morphology ratios. results dust mainly lies west Hu-Line, mixed distributes near dominates over North China Plain cities southern China. insights into China’s future clean policy making environmental research.

Language: Английский

---

The Effects of PM_2.5 Concentrations and Relative Humidity on Atmospheric Visibility in Beijing

Journal of Geophysical Research Atmospheres, Journal Year: 2019, Volume and Issue: 124(4), P. 2235 - 2259

Published: Jan. 29, 2019

Abstract Atmospheric visibility is often used as a proxy for ambient air quality. However, in addition to the concentrations of particulate matter, also affected by meteorological conditions. The relative contributions PM 2.5 and conditions are not yet clear. In this study, individual humidity (RH) measured based on observations at 12 stations Beijing. We find that decreases quickly increase clean condition slowly when exceed 100 μg/m 3 . linearly lower than 50 ; however, there tends be an exponential relationship increase. can explain 50% variance high‐humidity environments, whereas fraction 10–15% 200 contrast, RH has little effect under dry When exceeds 40%, atmospheric display inversely proportional with polluted conditions, respectively. Under highly up 40% associated RH. dominate variations or low concentrations, become increasingly important difference aerosol types weather uncertainties correlation coefficients between /RH. This study emphasizes employing pollution.

Language: Английский

---

Interactions of Asian mineral dust with Indian summer monsoon: Recent advances and challenges

Earth-Science Reviews, Journal Year: 2021, Volume and Issue: 215, P. 103562 - 103562

Published: Feb. 21, 2021

The Indian summer monsoon (ISM) is one of the world's strongest systems that brings about eighty percent annual rainfall to subcontinent and impacts livelihood more than a quarter population. Meanwhile, Asia second largest dust source—with major deserts in Middle East, Central East Asia. interactions between Asian ISM have received increasing attention recent decades. Dust particles can modulate circulation precipitation through absorption solar terrestrial radiation when suspending atmosphere deposited snow ice at surface by acting as nuclei liquid clouds. In turn, affect emissions, transport, deposition atmospheric wet scavenging. This review provides a) an overview several physical mechanisms behind particularly dust, b) new hypothesis explain observed positive correlation rainfall, c) summary current progress challenges simulation climate models. Finally, we propose future research directions aimed improving dust–monsoon simulations terms long-term variability, absorbing property, anthropogenic contributions.

Language: Английский

---

Dynamics of particulate emissions in the presence of autonomous vehicles

Open Mathematics, Journal Year: 2025, Volume and Issue: 23(1)

Published: Jan. 1, 2025

Abstract Around one third of CO 2 {{\rm{CO}}}_{2} emissions in the atmosphere are linked to vehicular traffic. Pollutant agents have an impact on environment, particular, increased presence particulate matter (PM) creates negative effects human health. This article examines how autonomy could positively reduce emission air pollutants due The methodology involves analyses PM as a function traffic conditions, especially autonomous vehicles (AVs) dampening waves. starting point is measurements that, gathered from real experiments involving fleet moving ring track, exhibit stop-and-go waves that dampened by control strategies implemented unique AV. Using system ordinary differential equations modeling principal chemical reactions atmosphere, it proved wave implies significant decrease at ground level. horizontal diffusion estimated partial combined with model for reactions. obtained outcomes show advantages given improvements flows and mitigation effect green barriers.

Language: Английский

---

Vertical Structures of Dust Aerosols over East Asia Based on CALIPSO Retrievals

Remote Sensing, Journal Year: 2019, Volume and Issue: 11(6), P. 701 - 701

Published: March 23, 2019

The spatiotemporal and especially the vertical distributions of dust aerosols play crucial roles in climatic effect aerosol. In present study, spatial-temporal distribution over East Asia was investigated using Cloud-Aerosol Lidar Infrared Pathfinder Satellite Observations (CALIPSO) retrievals (01/2007–12/2011) from perspective frequency occurrence (FDO), top layer height (TH) profile aerosol subtypes. results showed that a typical belt generated source regions (the Taklimakan Gobi Deserts), latitude range 25°N~45°N reaching eastern China, Japan Korea and, eventually, Pacific Ocean. High frequencies were found regions, with seasonal sequence high to low as follows: spring, summer, autumn winter. Vertically, FDOs peaked at about 2 km regions. contrast, decreased altitude downwind On getting higher higher. TH varied 1.9–3.1 above surface elevation (a.s.e.), values areas, seasonally descending winter accord variation boundary height. annual AOD (Aerosol Optical Depth) generally characterized by two centers Asia. percent contribution Dust Aerosol Depth total winter, summer. extinction coefficient revealed predominance pure particles mixture pollutants coefficients Desert had pattern summer autumn. study offered an understanding horizontal structures can be used evaluate performance transport models.

Language: Английский

---

High contribution of vehicle emissions to fine particulate pollutions in Lanzhou, Northwest China based on high-resolution online data source appointment

The Science of The Total Environment, Journal Year: 2021, Volume and Issue: 798, P. 149310 - 149310

Published: July 29, 2021

Language: Английский

---

Atmospheric aerosol size distribution impacts radiative effects over the Himalayas via modulating aerosol single-scattering albedo

npj Climate and Atmospheric Science, Journal Year: 2023, Volume and Issue: 6(1)

Published: May 30, 2023

Abstract The single-scattering albedo (SSA) of atmospheric aerosols is a key parameter that controls aerosol radiative effects. variation SSA thought to be mainly regulated by absorption in the Himalayas and South Asia, but observations contradict this idea. In situ field campaigns conducted over two Himalayan sites revealed was strongly dependent on scattering weakly correlated with absorption. Observational results combined Mie theory further illustrated primarily modulated size distribution rather than Aerosol Robotic Network (AERONET) data showed similar impacts forcing efficiencies were significantly SSA. therefore considerably affects modulating Himalayas. This study highlighted influence Himalayas, which has important implications for understanding effects globally.

Language: Английский

---

The impact of short-lived climate pollutants on the human health

Environmental Pollution and Management, Journal Year: 2024, Volume and Issue: 1, P. 1 - 14

Published: April 10, 2024

The hypothesis of short-lived climate pollutants (SLCPs) has been formulated to develop ways address global warming by identifying human-made air constituents that cause beneficial radiative forcing. main features the SLCPs include methane, hydrofluorocarbons, tropospheric ozone, black carbon, and methane. United Nations Environment Programme (UNEP) World Meteorological Organization (WMO) suggested a scenario regarding potential mitigation in which SLCP reduction policies, addition those for long-lived greenhouse gases (LLGHGs), may result surface temperature drop around 0.5 °C. In 2012, Climate Clean Air Coalition (CCAC) began worldwide project intending simultaneously health issue via waste. Following Paris Agreement COP21 2015 established target not go above two degrees Celsius mark reduce emissions 1.5 compared pre-industrial period, an integrated approach LLGHG grown increasingly critical. earth's should exceed Celsius. These are anticipated contribute as much half heat from human activities if no effort is made curb their next few decades. impacts indoor outdoor pollution untimely deaths up 7 million individuals yearly. primary culprits SLCPs. Fast action on major emission sources, such widespread implementation clean cooking heating fuels technology, opportunity save almost 2.4 lives annually.

Language: Английский

---

Relationship between Asian monsoon strength and transport of surface aerosols to the Asian Tropopause Aerosol Layer (ATAL): interannual variability and decadal changes

Atmospheric chemistry and physics, Journal Year: 2019, Volume and Issue: 19(3), P. 1901 - 1913

Published: Feb. 12, 2019

Abstract. In this study, we have investigated the interannual variability and decadal trend of carbon monoxide (CO), carbonaceous aerosols (CA) mineral dust in Asian Tropopause Aerosol Layer (ATAL) relation to varying strengths South summer monsoon (SASM) using MERRA-2 reanalysis data (2001–2015). Results show that during period, aforementioned ATAL constituents exhibit strong rising trends connected variations strength SASM. During years, anticyclone (AMA) is more expansive shifted northward compared weak years. spite effect quenching biomass burning emissions CO CA by increased precipitation, as well removal washout from surface mid-troposphere regions, all three are found be abundant an elongated accumulation zone ATAL, on southern flank expanded AMA. Enhanced transport overshooting deep convection over preferred pathways Himalayan-Gangetic Plain (HGP) Sichuan Basin (SB). The long-term positive robust, while due its large variability. associated with increasing AMA, earlier enhanced vertical HGP SB outweighing reduction mid-troposphere.

Language: Английский

---