12 results match your criteria Atmospheric Research[Journal]

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Changes in the ozone chemical regime over the contiguous United States inferred by the inversion of NO and VOC emissions using satellite observation.

Atmos Res 2022 Jun;270:1-14

Air Resources Laboratory, National Oceanic and Atmospheric Administration, College Park, MD, USA.

To investigate changes in the ozone (O) chemical production regime over the contiguous United States (CONUS) with accurate knowledge of concentrations of its precursors, we applied an inverse modeling technique with Ozone Monitoring Instrument (OMI) tropospheric nitrogen dioxide (NO) and total formaldehyde (HCHO) retrieval products in the summers of 2011, 2014, and 2017, years in which United States National Emission Inventory were based. The inclusion of dynamic chemical lateral boundary conditions and lightning-induced nitric oxide emissions significantly account for the contribution of background sources in the free troposphere. Satellite-constrained nitrogen oxide (NO) and non-methane volatile organic compounds (NMVOCs) emissions mitigate the discrepancy between satellite and modeled columns: the inversion suggested 2. Read More

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Mimicking atmospheric photochemical modelling with a deep neural network.

Atmos Res 2022 Jan;265:1-11

State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China.

Fast and accurate prediction of ambient ozone (O) formed from atmospheric photochemical processes is crucial for designing effective O pollution control strategies in the context of climate change. The chemical transport model (CTM) is the fundamental tool for O prediction and policy design, however, existing CTM-based approaches are computationally expensive, and resource burdens limit their usage and effectiveness in air quality management. Here we proposed a novel method (noted as DeepCTM) that using deep learning to mimic CTM simulations to improve the computational efficiency of photochemical modeling. Read More

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January 2022

Assessment of the coronavirus disease 2019 (COVID-19) pandemic imposed lockdown and unlock effects on black carbon aerosol, its source apportionment, and aerosol radiative forcing over an urban city in India.

Atmos Res 2022 Apr 16;267:105924. Epub 2021 Nov 16.

Space and Atmospheric Sciences Division, Physical Research Laboratory, Ahmedabad 380009, India.

A nationwide lockdown was imposed in India due to the Coronavirus Disease 2019 (COVID-19) pandemic which significantly reduced the anthropogenic emissions. We examined the characteristics of equivalent black carbon (eBC) mass concentration and its source apportionment using a multiwavelength aethalometer over an urban site (Ahmedabad) in India during the pandemic induced lockdown period of year 2020. For the first time, we estimate the changes in BC, its contribution from fossil (eBC ) and wood (eBC ) fuels during lockdown (LD) and unlock (UL) periods in 2020 with respect to 2017 to 2019 (). Read More

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Radiative effects of reduced aerosol emissions during the COVID-19 pandemic and the future recovery.

Atmos Res 2021 Dec 23;264:105866. Epub 2021 Sep 23.

Royal Netherlands Meteorological Institute, De Bilt, Netherlands.

The pandemic in 2020 caused an abrupt change in the emission of anthropogenic aerosols and their precursors. We estimate the associated change in the aerosol radiative forcing at the top of the atmosphere and the surface. To that end, we perform new simulations with the CMIP6 global climate model EC-Earth3. Read More

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December 2021

Air quality changes in cities during the COVID-19 lockdown: A critical review.

Atmos Res 2021 Dec 25;264:105823. Epub 2021 Aug 25.

Department of Civil and Environmental Engineering, National University of Singapore, Singapore 117576, Singapore.

In response to the rapid spread of coronavirus disease-2019 (COVID-19) within and across countries and the need to protect public health, governments worldwide introduced unprecedented measures such as restricted road and air travel and reduced human mobility in 2020. The curtailment of personal travel and economic activity provided a unique opportunity for researchers to assess the interplay between anthropogenic emissions of primary air pollutants, their physical transport, chemical transformation, ultimate fate and potential health impacts. In general, reductions in the atmospheric levels of outdoor air pollutants such as particulate matter (PM), nitrogen dioxide (NO), carbon monoxide (CO), sulfur dioxide (SO), and volatile organic compounds (VOCs) were observed in many countries during the lockdowns. Read More

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December 2021

Reduction of surface radiative forcing observed from remote sensing data during global COVID-19 lockdown.

Atmos Res 2021 Oct 11;261:105729. Epub 2021 Jun 11.

Collaborative Innovation Centre on Forecast and Evaluation of Meteorological Disasters, Key Laboratory of Meteorological Disaster, Ministry of Education, International Joint Laboratory on Climate and Environment Change, Key laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration, School of Atmospheric Physics, Nanjing University of Information Science and Technology, Nanjing 210044, China.

The calamity of the COVID-19 pandemic during the early half of 2020 not only caused a huge physical and economic loss but altered the social behavior of the whole world. The social and economic stagnation imposed in many countries and served as a major cause of perturbation in atmospheric composition. This paper utilized the relation between atmospheric composition and surface radiation and analyzed the impact of global COVID-19 lockdown on land surface solar and thermal radiation. Read More

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October 2021

COVID-19 pandemic in Wuhan: Ambient air quality and the relationships between criteria air pollutants and meteorological variables before, during, and after lockdown.

Atmos Res 2021 Mar 12;250:105362. Epub 2020 Nov 12.

College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China.

As a result of the lockdown (LD) control measures enacted to curtail the COVID-19 pandemic in Wuhan, almost all non-essential human activities were halted beginning on January 23, 2020 when the total lockdown was implemented. In this study, changes in the concentrations of the six criteria air pollutants (PM, PM, SO, NO, CO, and O) in Wuhan were investigated before (January 1 to 23, 2020), during (January 24 to April 5, 2020), and after the COVID-19 lockdown (April 6 to June 20, 2020) periods. Also, the relationships between the air pollutants and meteorological variables during the three periods were investigated. Read More

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Changes of air quality and its associated health and economic burden in 31 provincial capital cities in China during COVID-19 pandemic.

Atmos Res 2021 Feb 20;249:105328. Epub 2020 Oct 20.

Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control, Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, School of Environmental Science and Engineering, Nanjing University of Information Science and Technology, Nanjing 210044, China.

With outbreak of the novel coronavirus disease (COVID-19), immediate prevention and control actions were imposed in China. Here, we conducted a timely investigation on the changes of air quality, associated health burden and economic loss during the COVID-19 pandemic (January 1 to May 2, 2020). We found an overall improvement of air quality by analyzing data from 31 provincial cities, due to varying degrees of NO, PM, PM and CO reductions outweighing the significant O increase. Read More

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February 2021

Advances in sunphotometer-measured aerosol optical properties and related topics in China: Impetus and perspectives.

Atmos Res 2021 Feb 26;249:105286. Epub 2020 Sep 26.

Biospheric Sciences Branch, Code 923, NASA/Goddard Space Flight Center, Greenbelt, MD, USA.

Aerosol is a critical trace component of the atmosphere. Many processes in the Earth's climate system are intimately related to aerosols via their direct and indirect radiative effects. Aerosol effects are not limited to these climatic aspects, however. Read More

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February 2021

Vertical Profiles of Droplet Size Distributions Derived from Cloud-Side Observations by the Research Scanning Polarimeter: Tests on Simulated Data.

Atmos Res 2020 Jul 25;239. Epub 2020 Feb 25.

Department of Physics, University of Maryland, Baltimore County, 1000 Hilltop Cir, Baltimore, MD 21250, USA.

The Research Scanning Polarimeter (RSP) is an airborne along-track scanner measuring the polarized and total reflectances with high angular resolution. It allows for accurate characterization of liquid water cloud droplet sizes using the rainbow structure in the polarized reflectance. RSP's observations also provide constraints on the cumulus cloud's 2D cross section, yielding estimates of its geometric shape. Read More

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Investigation of the 3-D actinic flux field in mountainous terrain.

Atmos Res 2011 Nov;102(3):300-310

Institute for Meteorology, University of Natural Resources and Life Sciences, Peter-Jordan-Straße 82, A-1190 Vienna, Austria.

During three field campaigns spectral actinic flux was measured from 290-500 nm under clear sky conditions in Alpine terrain and the associated O3- and NO2-photolysis frequencies were calculated and the measurement products were then compared with 1-D- and 3-D-model calculations. To do this 3-D-radiative transfer model was adapted for actinic flux calculations in mountainous terrain and the maps of the actinic flux field at the surface, calculated with the 3-D-radiative transfer model, are given. The differences between the 3-D- and 1-D-model results for selected days during the campaigns are shown, together with the ratios of the modeled actinic flux values to the measurements. Read More

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November 2011

Measuring the influence of aerosols and albedo on sky polarization.

Atmos Res 2010 Nov;98(2-4):363-367

Division for Biomedical Physics, Department of Physiology and Medical Physics, Innsbruck Medical University, Innsbruck, Austria ; Department of Physics, University of California, Berkeley, USA.

All-sky distributions of the polarized radiance are measured using an automated fish-eye camera system with a rotating polarizer. For a large range of aerosol and surface albedo situations, the influence on the degree of polarization and sky radiance is investigated. The range of aerosol optical depth and albedo is 0. Read More

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November 2010
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