Article
Environmental Sciences
Chao Wang, Xingqin An, Defeng Zhao, Zhaobin Sun, Linsen Jiang, Jiangtao Li, Qing Hou
Summary: This study presents the development and validation of the gaseous chemistry adjoint module for the GRAPES-CUACE meteorological-chemical model system. The adjoint model accurately captures the relationship between ozone concentration and precursor emissions, providing valuable guidance for environmental control policies.
SCIENCE OF THE TOTAL ENVIRONMENT
(2022)
Article
Environmental Sciences
Yue Tan, Tao Wang
Summary: This study analyzed the impact of the citywide lockdown in Shanghai in April and May 2022 on ozone (O-3) concentrations. Despite reductions in nitrogen dioxide (NO2) and formaldehyde (HCHO) concentrations, the study found that the ozone concentrations increased during the lockdown period. The results suggest that future emission reductions alone may not be sufficient to eliminate ozone pollution in urban areas without additional control measures for volatile organic compounds (VOCs) or substantial decreases in NOx emissions.
ATMOSPHERIC CHEMISTRY AND PHYSICS
(2022)
Article
Environmental Sciences
Yusi Liu, Guiqian Tang, Baoxian Liu, Xiao Zhang, Qihua Li, Qihou Hu, Yu Wang, Miao Yu, Yang Sun, Dongsheng Ji, Yinghong Wang, Yuesi Wang
Summary: This study confirms the transition of ozone formation sensitivity and proposes that NOx control is effective in dealing with high ozone concentrations. The research also highlights the impact of emission standards and meteorological conditions on near-surface ozone and NOx concentrations.
ATMOSPHERIC ENVIRONMENT
(2022)
Article
Green & Sustainable Science & Technology
Mengya Wang, Tao Huang, David C. Wong, Kin Fai Ho, Guanghui Dong, Steve H. L. Yim
Summary: This study introduces an adjoint-based optimization framework to facilitate health-oriented O3 control in the Pearl River Delta Region (PRD). Results show that the regional O3 health benefits can be increased by 16-27% under current emission reduction policy, with significant reductions in NOx emissions observed in highly developed and populated areas such as Shenzhen and urban Guangzhou.
JOURNAL OF CLEANER PRODUCTION
(2021)
Article
Meteorology & Atmospheric Sciences
Guiqian Tang, Yusi Liu, Jinqiang Zhang, Baoxian Liu, Qihua Li, Jie Sun, Yinghong Wang, Yuejian Xuan, Yunting Li, Jinxiu Pan, Xin Li, Yuesi Wang
Summary: The study found that ozone concentrations below the ground increased significantly before 2016 and slightly decreased after 2016, while ozone concentrations above the ground slightly increased before 2016 and significantly decreased after 2016. These trends were mainly attributed to ozone precursors, leading to a transition in ozone production sensitivity from VOC to NOx.
ATMOSPHERIC RESEARCH
(2021)
Article
Environmental Sciences
Jian Sun, Zhenxing Shen, Ruonan Wang, Guohui Li, Yue Zhang, Bin Zhang, Kun He, Zhuoyue Tang, Hongmei Xu, Linli Qu, Steven Sai Hang Ho, Suixin Liu, Junji Cao
Summary: Tropospheric ozone pollution has become prominent in the North China Plain in China over the past decade. Through measurements and simulations in Luoyang City in 2019, it was found that industrial and traffic emissions were the main sources of VOC pollution in urban areas, and O-3 formation was collectively controlled by VOCs and NOx. The study supports the effectiveness of simultaneous controls of NOx and VOCs in reducing tropospheric O-3 and suggests that joint regional control policies have the potential to address O-3 pollution in China.
ENVIRONMENT INTERNATIONAL
(2021)
Article
Environmental Sciences
Li Luo, Siqi Wu, Renjian Zhang, Yunfei Wu, Jiawei Li, Shuh-ji Kao
Summary: The isotopic fractionation among NOy species can affect the evaluation of NOx sources. This study integrated aerosol 815N-NO3- data and fNO2 ratios to investigate the nitrogen isotope fractionation factors (As) in the Beijing-Tianjin-Hebei region from 2013 to 2018. The results showed significant seasonal patterns in both aerosol 815N-NO3- and As, emphasizing the importance of considering As when using atmospheric 815N-NO3- to quantify NOx source allocation.
SCIENCE OF THE TOTAL ENVIRONMENT
(2023)
Article
Meteorology & Atmospheric Sciences
Daniel A. Jaffe, Matthew Ninneman, Hei Chun Chan
Summary: The study found that NO2 concentrations in the U.S. have steadily decreased since 1995, with many areas transitioning to a NOx-limited regime for O-3 production. While the eastern regions have made significant progress in meeting the O-3 standard, the midwestern and western regions have shown less improvement in peak O-3 concentrations.
JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES
(2022)
Article
Environmental Sciences
Yu-Hao Mao, Shukun Yu, Yongjie Shang, Hong Liao, Nan Li
Summary: Surface ozone concentrations in the Yangtze River Delta (YRD) region in China have shown an increase due to human emissions of nitrogen oxide (NOx) and volatile organic compounds (VOCs). Reducing VOCs emissions is found to be the most effective method for controlling ozone in the region. The study suggests that with the continued reduction of VOCs (NOx) emissions in the YRD, the growth of ozone will be stopped from May to September but may continue in October.
FRONTIERS IN ENVIRONMENTAL SCIENCE
(2022)
Article
Geosciences, Multidisciplinary
Shengqiang Zhu, James Poetzscher, Juanyong Shen, Siyu Wang, Peng Wang, Hongliang Zhang
Summary: This study utilized comprehensive satellite observations and chemical transport modeling to investigate O-3 variations in China during the COVID-19 pandemic. The results showed significant increases in O-3 levels in the North China Plain and Yangtze River Delta, attributed to enhanced atmospheric oxidation capacity and reduced NOx emissions. The shift in O-3 formation mechanisms during lockdown suggests the need for balanced NOx and VOC emissions control policies in the future.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Environmental Sciences
Xinliang Cheng, Liqiang Wang, Lijuan Fang, Shiyan Chen, Xin Zhou, Jingjun Ma, Yuqing Pan, Pengfei Li
Summary: The accurate identification of ozone (O-3) production sensitivity is crucial for developing pollution control policies. This study combines nitrogen oxide (NOx) and particle uptakes to optimize peroxy radical loss estimates and analyze the relative sensitivity in Chun'an, China. The results show that the dominant precursor for O-3 production sensitivity shifts from volatile organic compounds (VOCs) in the morning and evening to NOx in the afternoon.
Article
Environmental Sciences
Jiayan Yu, Lingshuo Meng, Yang Chen, Huifang Zhang, Jianguo Liu
Summary: Concerns have been raised about near-surface ozone pollution in Lhasa, with limited understanding of its formation and distribution. Volatile organic compounds and nitrogen oxides are identified as crucial factors in controlling ozone formation, and reducing anthropogenic emissions is an effective way to decrease ozone concentrations.
Article
Multidisciplinary Sciences
Xiao Lu, Xingpei Ye, Mi Zhou, Yuanhong Zhao, Hongjian Weng, Hao Kong, Ke Li, Meng Gao, Bo Zheng, Jintai Lin, Feng Zhou, Qiang Zhang, Dianming Wu, Lin Zhang, Yuanhang Zhang
Summary: The study reveals that soil emissions of nitrogen oxides in the North China Plain significantly impact the sensitivity of ozone pollution to anthropogenic emissions, suggesting that additional measures beyond reducing combustion emissions are needed to effectively mitigate ozone pollution.
NATURE COMMUNICATIONS
(2021)
Article
Environmental Sciences
Feng Hu, Pinhua Xie, Xin Tian, Jin Xu, Ang Li, Aurelia Lupascu, Tim Butler, Zhaokun Hu, Yinsheng Lv, Zhidong Zhang, Jiangyi Zheng
Summary: The Yangtze River Delta frequently experiences ozone pollution events, and the factors influencing these events include weather patterns and regional ozone transport. By studying ozone source attribution and analyzing weather patterns, the mechanisms and contributors have been uncovered. This research is significant for understanding the ozone transport mechanism in the Yangtze River Delta and optimizing measures for controlling heavy ozone pollution.
SCIENCE OF THE TOTAL ENVIRONMENT
(2024)
Article
Environmental Sciences
Xun Li, Momei Qin, Lin Li, Kangjia Gong, Huizhong Shen, Jingyi Li, Jianlin Hu
Summary: This study examined the application of four photochemical indicators in the Yangtze River Delta region in China and found that they had high accuracy. Among them, HCHO/NO2 and HCHO/NOy showed the most consistency, while PH2O2/PHNO3 tended to underestimate the positive response of O-3 to NOx. Additionally, the methodology used to derive the threshold values may introduce uncertainties in the application of photochemical indicators.
ATMOSPHERIC CHEMISTRY AND PHYSICS
(2022)
Article
Public, Environmental & Occupational Health
Jeffrey R. Brook, Eleanor M. Setton, Evan Seed, Mahdi Shooshtari, Dany Doiron
Article
Environmental Sciences
Anders C. Erickson, Michael Brauer, Tanya Christidis, Lauren Pinault, Daniel L. Crouse, Aaron van Donkelaar, Scott Weichenthal, Amanda Pappin, Michael Tjepkema, Randall V. Martin, Jeffrey R. Brook, Perry Hystad, Richard T. Burnett
ENVIRONMENTAL RESEARCH
(2019)
Article
Environmental Sciences
Jun-Wei Xu, Randall V. Martin, Barron H. Henderson, Jun Meng, Y. Burak Oztaner, Jenny L. Hand, Amir Hakami, Madeleine Strum, Sharon B. Phillips
ATMOSPHERIC ENVIRONMENT
(2019)
Article
Environmental Sciences
Tanya Christidis, Anders C. Erickson, Amanda J. Pappin, Daniel L. Crouse, Lauren L. Pinault, Scott A. Weichenthal, Jeffrey R. Brook, Aaron van Donkelaar, Perry Hystad, Randall V. Martin, Michael Tjepkema, Richard T. Burnett, Michael Brauer
ENVIRONMENTAL HEALTH
(2019)
Article
Environmental Sciences
Amanda J. Pappin, Tanya Christidis, Lauren L. Pinault, Dan L. Crouse, Jeffrey R. Brook, Anders Erickson, Perry Hystad, Chi Li, Randall V. Martin, Jun Meng, Scott Weichenthal, Aaron van Donkelaar, Michael Tjepkema, Michael Brauer, Richard T. Burnett
ENVIRONMENTAL HEALTH PERSPECTIVES
(2019)
Article
Public, Environmental & Occupational Health
Dan L. Crouse, Anders C. Erickson, Tanya Christidis, Lauren Pinault, Aaron van Donkelaar, Chi Li, Jun Meng, Randall Martin, Michael Tjepkema, Perry Hystad, Rick Burnett, Amanda Pappin, Michael Brauer, Scott Weichenthal
Article
Environmental Sciences
Congmeng Lyu, Shannon L. Capps, Amir Hakami, Shunliu Zhao, Jaroslav Resler, Gregory R. Carmichael, Adrian Sandu, Armistead G. Russell, Tianfeng Chai, Daven K. Henze
ENVIRONMENTAL RESEARCH LETTERS
(2019)
Article
Psychology, Biological
Huizhong Shen, Guofeng Shen, Yilin Chen, Armistead G. Russell, Yongtao Hu, Xiaoli Duan, Wenjun Meng, Yang Xu, Xiao Yun, Baolei Lyu, Shunliu Zhao, Amir Hakami, Jianping Guo, Shu Tao, Kirk R. Smith
Summary: Despite a decrease in outdoor PM2.5 during the COVID-19 quarantine in China, overall population exposure to PM2.5 increased. This was mainly driven by population migration from urban to rural areas before the Spring Festival, coupled with increased household energy consumption during the quarantine, leading to a higher percentage of people exposed to rural household air pollution.
NATURE HUMAN BEHAVIOUR
(2021)
Article
Environmental Sciences
Congmeng Lyu, Shannon L. Capps, Kent Kurashima, Daven K. Henze, Gordon Pierce, Amir Hakami, Shunliu Zhao, Jaroslav Resler, Gregory R. Carmichael, Adrian Sandu, Armistead G. Russell, Tianfeng Chai, Jana Milford
Summary: Recent expansion of oil and natural gas production activities in the Denver-Julesburg Basin have led to significant increase in nonmethane hydrocarbon (NMHC) emissions, contributing to ground-level ozone formation. Using different methods, it was estimated that O&NG activities in Platteville and Denver have different contributions to NMHC mixing ratios. Vehicle emissions in Denver have a larger impact on NMHC levels compared to O&NG activities.
ATMOSPHERIC ENVIRONMENT
(2021)
Article
Environmental Sciences
Sina Voshtani, Richard Menard, Thomas W. Walker, Amir Hakami
Summary: This study presents a parametric Kalman filter data assimilation system using GOSAT methane observations within the hemispheric CMAQ model. The system can generate forecasts and analyses of concentrations and computes its evolving error variance while remaining computationally competitive. The study also discusses extensions to include methane transport and emissions in the CMAQ model and perform a bias correction for the GOSAT observations.
Article
Environmental Sciences
Sina Voshtani, Richard Menard, Thomas W. Walker, Amir Hakami
Summary: We applied the parametric variance Kalman filter (PvKF) data assimilation to GOSAT methane observations and optimized the methane field with its error variance. The assimilation results were validated and showed significant improvement compared to available observations. Additionally, the method was able to capture the spatial structure of bias and uncertainty reduction across the Northern Hemisphere.
Article
Environmental Sciences
Sina Voshtani, Richard Menard, Thomas W. Walker, Amir Hakami
Summary: This study combines parametric variance Kalman filter (PvKF) assimilation with 4D-Var inversion to improve methane emissions estimation. It revisits the assumptions made in the traditional 4D-Var algorithm and objectively accounts for error correlations and the evolution of analysis error variances. Experimental results show that using PvKF optimal analysis instead of the model forecast improves posterior emissions estimate and retains the effects of background correlation structures, resulting in more reliable estimates of posterior emissions. The addition of PvKF optimal analysis field benefits the 4D-Var inversion by reducing computational time.
Article
Environmental Sciences
Yilin Chen, Huizhong Shen, Jennifer Kaiser, Yongtao Hu, Shannon L. Capps, Shunliu Zhao, Amir Hakami, Jhih-Shyang Shih, Gertrude K. Pavur, Matthew D. Turner, Daven K. Henze, Jaroslav Resler, Athanasios Nenes, Sergey L. Napelenok, Jesse O. Bash, Kathleen M. Fahey, Gregory R. Carmichael, Tianfeng Chai, Lieven Clarisse, Pierre-Francois Coheur, Martin Van Damme, Armistead G. Russell
Summary: Ammonia emissions have significant impacts on air quality and nitrogen deposition, with large uncertainties existing in bottom-up emission inventories. This study utilizes satellite measurements and modeling tools to optimize NH3 emission estimates, revealing a 26% underestimation in the 2011 NEI with overestimation in the Midwest and underestimation in the Southern States.
ATMOSPHERIC CHEMISTRY AND PHYSICS
(2021)
Article
Geosciences, Multidisciplinary
Shunliu Zhao, Matthew G. Russell, Amir Hakami, Shannon L. Capps, Matthew D. Turner, Daven K. Henze, Peter B. Percell, Jaroslav Resler, Huizhong Shen, Armistead G. Russell, Athanasios Nenes, Amanda J. Pappin, Sergey L. Napelenok, Jesse O. Bash, Kathleen M. Fahey, Gregory R. Carmichael, Charles O. Stanier, Tianfeng Chai
GEOSCIENTIFIC MODEL DEVELOPMENT
(2020)
Article
Environmental Sciences
Matthew Russell, Amir Hakami, Paul A. Makar, Ayodeji Akingunola, Junhua Zhang, Michael D. Moran, Qiong Zheng
ATMOSPHERIC CHEMISTRY AND PHYSICS
(2019)