Classification of aerosols using particle linear depolarization ratio (PLDR) over seven urban locations of Asia

Chemosphere, Journal Year: 2024, Volume and Issue: 350, P. 141119 - 141119

Published: Jan. 7, 2024

Language: Английский

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Peculiar weather patterns effects on air pollution and COVID-19 spread in Tokyo metropolis

Environmental Research, Journal Year: 2023, Volume and Issue: 228, P. 115907 - 115907

Published: April 18, 2023

As a pandemic hotspot in Japan, between March 1, 2020–October 2022, Tokyo metropolis experienced seven COVID-19 waves. Motivated by the high rate of incidence and mortality during seventh wave, environmental/health challenges we conducted time-series analysis to investigate long-term interaction air quality climate variability with viral Tokyo. Through daily time series geospatial observational pollution/climate data, death cases, this study compared environmental conditions multiwaves. In spite five State Emergency (SOEs) restrictions associated pandemic, (2020–2022) period recorded low improvements relative (2015–2019) average annual values, namely: Aerosol Optical Depth increased 9.13% 2020 year, declined 6.64% 2021, 12.03% 2022; particulate matter PM2.5 PM10 decreased 2020, 2022 years 10.22%, 62.26%, 0.39%, respectively 4.42%, 3.95%, 5.76%. For (2021–2022) ratio PM2.5/PM10 was (0.319 ± 0.1640), showing higher contribution aerosol loading traffic-related coarse particles comparison fine particles. The highest rates cases wave (1 July 2022–1 October 2022) may be attributed accumulation near ground levels pollutants pathogens due to: 1) peculiar persistent atmospheric anticyclonic circulation strong positive anomalies geopotential height at 500 hPa; 2) lower Planetary Boundary Layer (PBL) heights; 3) maximum temperature land surface prolonged heat waves (HWs) summer 4) no imposed restrictions. Such findings can guide public decision-makers design proper strategies curb pandemics under stable weather HWs large metropolitan areas.

Language: Английский

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Research of Two Dust Transport Pollution in Northern China in 2023: Perspectives from LiDAR and Multi source Data

Atmospheric Pollution Research, Journal Year: 2025, Volume and Issue: unknown, P. 102441 - 102441

Published: Feb. 1, 2025

Language: Английский

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Advanced simulation and measurement of skylight polarization patterns across distinct aerosol type environments

The Science of The Total Environment, Journal Year: 2025, Volume and Issue: 967, P. 178768 - 178768

Published: Feb. 12, 2025

Language: Английский

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Measurement report: Dust and anthropogenic aerosols vertical distributions over Beijing―dense aerosols gathered at the top of the mixing layer

Published: June 27, 2023

Abstract. Over the past decades, Beijing has been suffering from persistent air pollution caused by both fine and coarse atmospheric particles. Although there are plenty of theoretical observational studies on aerosols in Beijing, most them only consider total aerosol concentrations focus heavy episodes, long‒term vertical distributions dust (coarse) anthropogenic (fine) their relationships with mixing layer height (MLH) have not revealed. In this study, mass concentration, MLH were retrieved polarization Raman lidar over May 2019 to February 2022. We found large amounts accumulate at top layer, which is noticeable summer, monthly mean concentration up 57 µg/m3. It mainly influenced southward transport upper air, where atmosphere relatively stable moist, favoring hygroscopic growth Dust discontinuous direction. Not ground but also lofted layers that reach several kilometers. The heights these exhibited apparent seasonal dependence, main gradually ascending 1.1 km about 2.5 April June below 3 October December. addition, a significant negative correlation between bottom MLH, an inverse function fit more suitable characterize relationship, while relationship insignificant. These results will enhance our understanding sophisticated interactions aerosols, regional northern China. help refine chemistry models improve surface prediction capabilities.

Language: Английский

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Seasonal patterns, vertical profiles, and sensitivity analysis of long-term O3 pollution observations in Hefei City, China

Atmospheric Pollution Research, Journal Year: 2024, Volume and Issue: 15(7), P. 102145 - 102145

Published: April 4, 2024

Language: Английский

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Estimation of the Seawater Lidar Ratio by MODIS: Spatial–Temporal Characteristics and Ecological Significance

Remote Sensing, Journal Year: 2023, Volume and Issue: 15(13), P. 3328 - 3328

Published: June 29, 2023

The lidar ratio of seawater is an essential quantity related to both retrieval and water constituent. However, few studies discuss its spatial–temporal characteristics ecological significance, which limits applications in remote sensing marine science. This paper investigates the significance using satellite passive sensing, validated by situ measurements. Spatially, nearshore values are higher than offshore, mainly owing high concentration colored dissolved organic matter water. Temporally, each hemisphere exhibits lower summer winter due annual boom–bust cycle phytoplankton. Furthermore, variability patterns nearly consistent with those chlorophyll-to-carbon ratio, implying phytoplankton physiology. These findings will provide foundation for application science sensing.

Language: Английский

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The Aerosol Optical Characteristics in Different Dust Events Based on a 532 nm and 355 nm Polarization Lidar in Beijing

Remote Sensing, Journal Year: 2023, Volume and Issue: 15(14), P. 3494 - 3494

Published: July 11, 2023

Extreme weather events are happening more frequently as a result of global climate change. Dust storms broke out in the spring 2017 China and drastically impacted local air quality. In this study, variety data, including aerosol vertical profiles, surface particle concentration, meteorological parameters, MODIS–derived optical depth, well backward trajectory analysis, were employed to analyze two dust from April May Beijing. The plumes mainly concentrated below 0.8 km, with peak PM10 values 1000 μg·m−3 300 cases. aerosols showed different distribution characteristics. pure case 1 4 5 had longer duration (2 days) presented larger extinction coefficient (2.27 km−1 at 355 nm 1.25 532 nm) than that mixed 2 on 17 (2.01 1.33 nm). depolarization ratio (PDR) remained constant (0.24 ± 0.03 1) km height. contrast, PDR profile (case 2) layer was split into regions—large exceeding 0.15 above 0.6 small 0.11 km. influence information also investigated, wind predominant through observing period. Mongolia, strong northwest winds, while near-surface pollution caused by combination long-transported sand emission. Furthermore, lidar-derived profiles mass concentrations cases presented. This study reveals characteristics production dissipation localized confirms efficacy thorough observations multiple approaches ground space monitor real time.

Language: Английский

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Measurement report: Dust and anthropogenic aerosols' vertical distributions over northern China dense aerosols gathered at the top of the mixing layer

Atmospheric chemistry and physics, Journal Year: 2023, Volume and Issue: 23(22), P. 14271 - 14292

Published: Nov. 16, 2023

Abstract. Over the past decades, northern China has been suffering from persistent air pollution caused by both fine and coarse atmospheric particles. Although there are plenty of theoretical observational studies on aerosols in China, most them only consider total aerosol concentrations focus heavy episodes; long-term vertical distributions dust (coarse) anthropogenic (fine) their relationships with mixing layer height (MLH) have not revealed. In this study, aerosols' mass concentration MLH were retrieved polarization Raman lidar over Beijing May 2019 to February 2022. We found that large amounts accumulate at top layer, which is noticeable summer, monthly mean up 57 µg m−3. It mainly influenced southward transport upper air, where atmosphere relatively stable moist, favoring hygroscopic growth Dust discontinuous direction, ground but also lofted layers reach several kilometers. The heights these exhibited apparent seasonal dependence, main gradually ascending 1.1 km about 2.5 April June below 3 October December. addition, a significant negative correlation between bottom MLH, an inverse function fit more suitable characterize relationship, while relationship insignificant. These results will enhance our understanding sophisticated interactions aerosols, regional China. help refine chemistry models improve surface prediction capabilities.

Language: Английский

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Aerosol Pollution over St. Petersburg in Different Seasons Based on the Results of Lidar Measurements from 2014 to 2022

Ecology and Industry of Russia, Journal Year: 2023, Volume and Issue: 27(9), P. 61 - 65

Published: Sept. 6, 2023

The results of long-term (during the 8-year period) observations aerosol optical depth in center St. Petersburg are presented, which performed using stationary lidar complex Resource Center "Observatory environmental safety", Research Park, University. It has been established that content particles over city prevails summer and spring seasons, while minimum aerosols is observed winter.

Language: Английский

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