Articles | Volume 21, issue 17
10 Sep 2021
Research article | 10 Sep 2021
Characteristics of surface energy balance and atmospheric circulation during hot-and-polluted episodes and their synergistic relationships with urban heat islands over the Pearl River Delta region
Ifeanyichukwu C. Nduka et al.
No articles found.
Jianping Guo, Jian Zhang, Tianmeng Chen, Kaixu Bai, Jia Shao, Yuping Sun, Ning Li, Jingyan Wu, Rui Li, Jian Li, Qiyun Guo, Jason B. Cohen, Panmao Zhai, Xiaofeng Xu, and Fei Hu
Earth Syst. Sci. Data Discuss.,
Preprint under review for ESSDShort summary
A global continental merged high-resolution (PBLH) dataset with a good accuracy compared to radiosonde is generated via machine learning algorithms, covering a time period from 2011 to 2021 with a 3-hour and 0.25º resolution in space and time. The machine learning model takes parameters derived from the ERA5 reanalysis and GLDAS product as input while PBLH biases between radiosonde and ERA5 as the learning targets. The merged PBLH is the sum of the predicted PBLH bias and the PBLH from ERA5.
Kaixu Bai, Ke Li, Mingliang Ma, Kaitao Li, Zhengqiang Li, Jianping Guo, Ni-Bin Chang, Zhuo Tan, and Di Han
Earth Syst. Sci. Data, 14, 907–927,Short summary
The Long-term Gap-free High-resolution Air Pollutant concentration dataset, providing gap-free aerosol optical depth (AOD) and PM2.5 and PM10 concentration with a daily 1 km resolution for 2000–2020 in China, is generated and made publicly available. This is the first long-term gap-free high-resolution aerosol dataset in China and has great potential to trigger multidisciplinary applications in Earth observations, climate change, public health, ecosystem assessment, and environment management.
Linye Song, Shangfeng Chen, Wen Chen, Jianping Guo, Conglan Cheng, and Yong Wang
Atmos. Chem. Phys., 22, 1669–1688,Short summary
This study shows that in most years when haze pollution (HP) over the North China Plain (NCP) is more (less) serious in winter, air conditions in the following spring are also worse (better) than normal. Conversely, there are some years when HP in the following spring is opposed to that in winter. It is found that North Atlantic sea surface temperature (SST) anomalies play important roles in HP evolution over the NCP. Thus North Atlantic SST is an important preceding signal for NCP HP evolution.
Boming Liu, Jianping Guo, Wei Gong, Yong Zhang, Lijuan Shi, Yingying Ma, Jian Li, Xiaoran Guo, Ad Stoffelen, Gerrit de Leeuw, and Xiaofeng Xu
Atmos. Meas. Tech. Discuss.,
Revised manuscript has not been submittedShort summary
Aeolus is the first satellite mission to directly observe wind profile information on a global scale. However, Aeolus wind products over China were thus far not evaluated by in-situ comparison. This work is the comparison of wind speed on a large scale between the Aeolus, ERA5 and RS , shedding important light on the data application of Aeolus wind products.
Jiachen Zhu, Amos P. K. Tai, and Steve Hung Lam Yim
Atmos. Chem. Phys., 22, 765–782,Short summary
This study assessed O3 damage to plant and the subsequent effects on meteorology and air quality in China, whereby O3, meteorology, and vegetation can co-evolve with each other. We provided comprehensive understanding about how O3–vegetation impacts adversely affect plant growth and crop production, and contribute to global warming and severe O3 air pollution in China. Our findings clearly pinpoint the need to consider the O3 damage effects in both air quality studies and climate change studies.
Peilin Song, Yongqiang Zhang, Jianping Guo, Jiancheng Shi, Tianjie Zhao, and Bing Tong
Earth Syst. Sci. Data Discuss.,
Revised manuscript accepted for ESSDShort summary
Soil moisture information is cruicial for understanding the earth surface, but currently available satellite-based soil moisture datasets are imperfect either in their spatio-temporal resolutions or in esnuring image completeness from cloudy weather. In this study, therefore, we developed one soil moisture data product over China that has tackled most of the above problems. This data product has great potential to promote investigation on earth hydrology and to be extended to the global scale.
Qingqing He, Mengya Wang, and Steve Hung Lam Yim
Atmos. Chem. Phys., 21, 18375–18391,Short summary
We explore the spatiotemporal relationship between PM2.5 and AOD over China using a multi-scale analysis with MODIS MAIAC 1 km aerosol observations and ground measurements. The impact factors (vertical distribution, relative humidity and terrain) on the relationship are quantitatively studied. Our results provide significant information on PM2.5 and AOD, which is informative for mapping high-resolution PM2.5 and furthering the understanding of aerosol properties and the PM2.5 pollution status.
Jianping Guo, Jian Zhang, Kun Yang, Hong Liao, Shaodong Zhang, Kaiming Huang, Yanmin Lv, Jia Shao, Tao Yu, Bing Tong, Jian Li, Tianning Su, Steve H. L. Yim, Ad Stoffelen, Panmao Zhai, and Xiaofeng Xu
Atmos. Chem. Phys., 21, 17079–17097,Short summary
The planetary boundary layer (PBL) is the lowest part of the troposphere, and boundary layer height (BLH) is the depth of the PBL and is of critical importance to the dispersion of air pollution. The study presents the first near-global BLH climatology by using high-resolution (5-10 m) radiosonde measurements. The variations in BLH exhibit large spatial and temporal dependence, with a peak at 17:00 local solar time. The most promising reanalysis product is ERA-5 in terms of modeling BLH.
Seoung Soo Lee, Kyung-Ja Ha, Manguttathil Gopalakrishnan Manoj, Mohammad Kamruzzaman, Hyungjun Kim, Nobuyuki Utsumi, Youtong Zheng, Byung-Gon Kim, Chang Hoon Jung, Junshik Um, Jianping Guo, Kyoung Ock Choi, and Go-Un Kim
Atmos. Chem. Phys., 21, 16843–16868,Short summary
Using a modeling framework, a midlatitude stratocumulus cloud system is simulated. It is found that cloud mass in the system becomes very low due to interactions between ice and liquid particles compared to that in the absence of ice particles. It is also found that interactions between cloud mass and aerosols lead to a reduction in cloud mass in the system, and this is contrary to an aerosol-induced increase in cloud mass in the absence of ice particles.
Zixia Liu, Martin Osborne, Karen Anderson, Jamie D. Shutler, Andy Wilson, Justin Langridge, Steve H. L. Yim, Hugh Coe, Suresh Babu, Sreedharan K. Satheesh, Paquita Zuidema, Tao Huang, Jack C. H. Cheng, and James Haywood
Atmos. Meas. Tech., 14, 6101–6118,Short summary
This paper first validates the performance of an advanced aerosol observation instrument POPS against a reference instrument and examines any biases introduced by operating it on a quadcopter drone. The results show the POPS performs relatively well on the ground. The impact of the UAV rotors on the POPS is small at low wind speeds, but when operating under higher wind speeds, larger discrepancies occur. It appears that the POPS measures sub-micron aerosol particles more accurately on the UAV.
Tianmeng Chen, Zhanqing Li, Ralph A. Kahn, Chuanfeng Zhao, Daniel Rosenfeld, Jianping Guo, Wenchao Han, and Dandan Chen
Atmos. Chem. Phys., 21, 6199–6220,Short summary
A convective cloud identification process is developed using geostationary satellite data from Himawari-8. Convective cloud fraction is generally larger before noon and smaller in the afternoon under polluted conditions, but megacities and complex topography can influence the pattern. A robust relationship between convective cloud and aerosol loading is found. This pattern varies with terrain height and is modulated by varying thermodynamic, dynamical, and humidity conditions during the day.
Zhiyuan Li, Kin-Fai Ho, Hsiao-Chi Chuang, and Steve Hung Lam Yim
Atmos. Chem. Phys., 21, 5063–5078,Short summary
This study established land-use regression (LUR) models using only routine air quality measurement data to support long-term health studies in an Asian metropolitan area. The established LUR models captured the spatial variability in exposure to air pollution with remarkable predictive accuracy. This is the first Asian study to evaluate intercity transferability of LUR models, and it highlights that there exist uncertainties when transferring LUR models between nearby cities.
Jianping Guo, Boming Liu, Wei Gong, Lijuan Shi, Yong Zhang, Yingying Ma, Jian Zhang, Tianmeng Chen, Kaixu Bai, Ad Stoffelen, Gerrit de Leeuw, and Xiaofeng Xu
Atmos. Chem. Phys., 21, 2945–2958,Short summary
Vertical wind profiles are crucial to a wide range of atmospheric disciplines. Aeolus is the first satellite mission to directly observe wind profile information on a global scale. However, Aeolus wind products over China have thus far not been evaluated by in situ comparison. This work is expected to let the public and science community better know the Aeolus wind products and to encourage use of these valuable data in future research and applications.
Boming Liu, Jianping Guo, Wei Gong, Yong Zhang, Lijuan Shi, Yingying Ma, Jian Li, Xiaoran Guo, Ad Stoffelen, Gerrit de Leeuw, and Xiaofeng Xu
Atmos. Chem. Phys. Discuss.,
Revised manuscript not acceptedShort summary
Vertical wind profiles are crucial to a wide range of atmospheric disciplines. Aeolus is the first satellite mission to directly observe wind profile information on a global scale. However, Aeolus wind products over China were thus far not evaluated by in-situ comparison. This work is expected to let the public and science community better know the Aeolus wind products and to encourage use of these valuable data in future researches and applications.
Kaixu Bai, Ke Li, Chengbo Wu, Ni-Bin Chang, and Jianping Guo
Earth Syst. Sci. Data, 12, 3067–3080,Short summary
PM2.5 data from the national air quality monitoring network in China suffered from significant inconsistency and inhomogeneity issues. To create a coherent PM2.5 concentration dataset to advance our understanding of haze pollution and its impact on weather and climate, we homogenized this PM2.5 dataset between 2015 and 2019 after filling in the data gaps. The homogenized PM2.5 data is found to better characterize the variation of aerosol in space and time compared to the original dataset.
Yang Yang, Min Chen, Xiujuan Zhao, Dan Chen, Shuiyong Fan, Jianping Guo, and Shaukat Ali
Atmos. Chem. Phys., 20, 12527–12547,Short summary
This study analyzed the impacts of aerosol–radiation interaction on radiation and meteorological forecasts using the offline coupling of WRF and high-frequency updated AOD simulated by WRF-Chem. The results revealed that aerosol–radiation interaction had a positive influence on the improvement of predictive accuracy, including 2 m temperature (~ 73.9 %) and horizontal wind speed (~ 7.8 %), showing potential prospects for its application in regional numerical weather prediction in northern China.
Ruqian Miao, Qi Chen, Yan Zheng, Xi Cheng, Yele Sun, Paul I. Palmer, Manish Shrivastava, Jianping Guo, Qiang Zhang, Yuhan Liu, Zhaofeng Tan, Xuefei Ma, Shiyi Chen, Limin Zeng, Keding Lu, and Yuanhang Zhang
Atmos. Chem. Phys., 20, 12265–12284,Short summary
In this study we evaluated the model performances for simulating secondary inorganic aerosol (SIA) and organic aerosol (OA) in PM2.5 in China against comprehensive datasets. The potential biases from factors related to meteorology, emission, chemistry, and atmospheric removal are systematically investigated. This study provides a comprehensive understanding of modeling PM2.5, which is important for studies on the effectiveness of emission control strategies.
Lang Wang, Amos P. K. Tai, Chi-Yung Tam, Mehliyar Sadiq, Peng Wang, and Kevin K. W. Cheung
Atmos. Chem. Phys., 20, 11349–11369,Short summary
We investigate the effects of future land use and land cover change (LULCC) on surface ozone air quality worldwide and find that LULCC can significantly influence ozone in North America and Europe via modifying surface energy balance, boundary-layer meteorology, and regional circulation. The strength of such “biogeophysical effects” of LULCC is strongly dependent on forest type and generally greater than the “biogeochemical effects” via changing deposition and emission fluxes alone.
Boming Liu, Jianping Guo, Wei Gong, Lijuan Shi, Yong Zhang, and Yingying Ma
Atmos. Meas. Tech., 13, 4589–4600,Short summary
Vertical wind profiles are crucial to a wide range of atmospheric disciplines. However, the wind profile across China remains poorly understood. Here we reveal the salient features of winds from the radar wind profile of China, including the main instruments, spatial coverage and sampling frequency. This work is expected to allow the public and scientific community to be more familiar with the nationwide network and encourage the use of these valuable data in future research and applications.
Haofei Wang, Zhengqiang Li, Yang Lv, Ying Zhang, Hua Xu, Jianping Guo, and Philippe Goloub
Atmos. Chem. Phys., 20, 8839–8854,Short summary
Lidar shows good performance in calculating the convective layer height in the daytime and the residual layer height at night, as well as having the potential to describe the stable layer height at night. The MLH seasonal change in Beijing indicates that it is low in winter and autumn and high in spring and summer. From 2014 to 2018, the magnitude of the diurnal cycle of MLH increased year by year. MLH from lidar shows better accuracy than a radiosonde when calculating surface pollution.
Haipeng Lin, Xu Feng, Tzung-May Fu, Heng Tian, Yaping Ma, Lijuan Zhang, Daniel J. Jacob, Robert M. Yantosca, Melissa P. Sulprizio, Elizabeth W. Lundgren, Jiawei Zhuang, Qiang Zhang, Xiao Lu, Lin Zhang, Lu Shen, Jianping Guo, Sebastian D. Eastham, and Christoph A. Keller
Geosci. Model Dev., 13, 3241–3265,Short summary
Online coupling of meteorology and chemistry models often presents maintenance issues with hard-wired coding. We present WRF-GC, an one-way online coupling of the WRF meteorological model and GEOS-Chem atmospheric chemistry model for regional atmospheric chemistry and air quality modeling. Our coupling structure allows future versions of either parent model to be immediately integrated into WRF-GC. The WRF-GC model was able to well reproduce regional PM2.5 with greater computational efficiency.
Wenchao Han, Zhanqing Li, Fang Wu, Yuwei Zhang, Jianping Guo, Tianning Su, Maureen Cribb, Jiwen Fan, Tianmeng Chen, Jing Wei, and Seoung-Soo Lee
Atmos. Chem. Phys., 20, 6479–6493,Short summary
Observational data and model simulation were used to analyze the daytime urban heat island intensity (UHII) under polluted and clean conditions in China. We found that aerosols reduce the UHII in summer but increase the UHII in winter. Two mechanisms, the aerosol radiative effect (ARE) and the aerosol dynamic effect (ADE), behave differently in summer and winter. In summer, the UHII is mainly affected by the ARE, and the ADE is weak, and the opposite is the case in winter.
Tianning Su, Zhanqing Li, Chengcai Li, Jing Li, Wenchao Han, Chuanyang Shen, Wangshu Tan, Jing Wei, and Jianping Guo
Atmos. Chem. Phys., 20, 3713–3724,Short summary
We study the role of aerosol vertical distribution in thermodynamic stability and PBL development. Under different aerosol vertical structures, the diurnal cycles of PBLH and PM2.5 show distinct characteristics. Large differences in the heating rate affect atmospheric buoyancy and stability differently under different aerosol structures. As a result, the aerosol–PBL interaction can be strengthened by the inverse aerosol structure and potentially neutralized by the decreasing structure.
Jing Wei, Zhanqing Li, Maureen Cribb, Wei Huang, Wenhao Xue, Lin Sun, Jianping Guo, Yiran Peng, Jing Li, Alexei Lyapustin, Lei Liu, Hao Wu, and Yimeng Song
Atmos. Chem. Phys., 20, 3273–3289,Short summary
This study introduced an enhanced space–time extremely randomized trees (STET) approach to improve the 1 km resolution ground-level PM2.5 estimates across China using the remote sensing technology. The STET model shows high accuracy and strong predictive power and appears to outperform most models reported by previous studies. Thus, it is of great importance for future air pollution studies at medium- or small-scale areas and will be applied to generate the historical PM2.5 dataset across China.
Kaixu Bai, Ke Li, Jianping Guo, Yuanjian Yang, and Ni-Bin Chang
Atmos. Meas. Tech., 13, 1213–1226,Short summary
A novel gap-filling method called the diurnal-cycle-constrained empirical orthogonal function (DCCEOF) is proposed. Cross validation indicates that this method gives high accuracy in predicting missing values in daily PM2.5 time series by accounting for the local diurnal phases, especially by reconstructing daily extrema that cannot be accurately restored by other approaches. The DCCEOF method can be easily applied to other data sets because of its self-consistent capability.
Zhen Liu, Yi Ming, Chun Zhao, Ngar Cheung Lau, Jianping Guo, Massimo Bollasina, and Steve Hung Lam Yim
Atmos. Chem. Phys., 20, 223–241,Short summary
OH and HO2 radicals are important trace constituents of the atmosphere that are closely coupled via several types of reaction. This paper describes a new laboratory method to simultaneously determine OH kinetics and HO2 yields from chemical processes. The instrument also provides some time resolution on HO2 detection allowing one to separate HO2 produced from the target reaction from HO2 arising from secondary chemistry. Examples of applications are presented.
Steve Hung Lam Yim, Yefu Gu, Matthew A. Shapiro, and Brent Stephens
Atmos. Chem. Phys., 19, 13309–13323,Short summary
This study assessed and quantified the transboundary air pollution (TAP) impact in Japan and South Korea. We found that ~70 % of annual ambient PM2.5 in Japan and South Korea was contributed by other countries in the region, and wet deposition had a greater impact on mixed forests in Japan and savannas in South Korea. Given these significant impacts of TAP in the region, it is paramount that cross–national efforts be taken to mitigate air pollution problems across East Asia.
Chun Zhao, Mingyue Xu, Yu Wang, Meixin Zhang, Jianping Guo, Zhiyuan Hu, L. Ruby Leung, Michael Duda, and William Skamarock
Geosci. Model Dev., 12, 2707–2726,Short summary
Simulations at global uniform and variable resolutions share similar characteristics of precipitation and wind in the refined region. The experiments reveal the significant impacts of resolution on simulating the distribution and intensity of precipitation and updrafts. This study provides evidence supporting the use of convection-permitting global variable-resolution simulations to study extreme precipitation.
Jing Wei, Yiran Peng, Rashed Mahmood, Lin Sun, and Jianping Guo
Atmos. Chem. Phys., 19, 7183–7207,Short summary
This study evaluates the suitability of 11 satellite-derived aerosol products in describing the spatio-temporal variations over the world. Our results show similar global patterns among these products but noticeable spatial heterogeneity and numerical differences over land regions. In general, MODIS products perform best at reflecting the spatial distributions and capturing the temporal trends of aerosol. This study help readers select a suitable aerosol dataset for their studies.
Guicai Ning, Shigong Wang, Steve Hung Lam Yim, Jixiang Li, Yuling Hu, Ziwei Shang, Jinyan Wang, and Jiaxin Wang
Atmos. Chem. Phys., 18, 13601–13615,Short summary
Under the effects of the Tibetan Plateau, dry low-pressure systems are often formed at 700 hPa in the Sichuan Basin, China, during winter. Here, we found that the activities of these dry low-pressure systems have significant influence on most winter heavy air pollution events in the Sichuan Basin. Influencing mechanisms have been summarized. The strong inversion layer above the atmospheric boundary layer induced by the low-pressure system plays a key role in the formation of heavy air pollution.
Jianping Guo, Huan Liu, Zhanqing Li, Daniel Rosenfeld, Mengjiao Jiang, Weixin Xu, Jonathan H. Jiang, Jing He, Dandan Chen, Min Min, and Panmao Zhai
Atmos. Chem. Phys., 18, 13329–13343,Short summary
Objective analysis has been used to discriminate between the local- and synoptic-scale precipitations based on wind and pressure fields at 500 hPa. Aerosol is found to be linked with changes in the vertical structure of precipitation, depending on precipitation regimes. There has been some success in separating aerosol and meteorological influences on precipitation.
Qianqian Wang, Zhanqing Li, Jianping Guo, Chuanfeng Zhao, and Maureen Cribb
Atmos. Chem. Phys., 18, 12797–12816,Short summary
Based on 11-year data of lightning flashes, aerosol optical depth (AOD) and composion, and meteorological variables, we investigated the roles of aerosol and meteorological variables in lightning. Pronounced differences in lightning were found between clean and polluted conditions. Systematic changes of boomerang shape were found in lightning frequency with AOD, with a turning point around AOD = 0.3, beyond which lightning activity is saturated for smoke aerosols but always suppressed by dust.
Hsiang-He Lee, Oussama Iraqui, Yefu Gu, Steve Hung-Lam Yim, Apisada Chulakadabba, Adam Yiu-Ming Tonks, Zhengyu Yang, and Chien Wang
Atmos. Chem. Phys., 18, 6141–6156,Short summary
Our study shows that across ASEAN 50 cities, these model results reveal that 39 % of observed low-visibility days can be explained by either fossil fuel burning or biomass burning emissions alone, a further 20 % by fossil fuel burning alone, a further 8 % by biomass burning alone, and a further 5 % by a combination of fossil fuel burning and biomass burning. The remaining 28 % of observed low-visibility days remains unexplained, likely due to emissions sources that have not been accounted for.
Xiaowan Zhu, Guiqian Tang, Jianping Guo, Bo Hu, Tao Song, Lili Wang, Jinyuan Xin, Wenkang Gao, Christoph Münkel, Klaus Schäfer, Xin Li, and Yuesi Wang
Atmos. Chem. Phys., 18, 4897–4910,Short summary
Our study first conducted a long-term observation of mixing layer height (MLH) with high resolution on the North China Plain (NCP), analyzed the spatiotemporal variations of regional MLH, investigated the reasons for MLH differences in the NCP and revealed the meteorological reasons for heavy haze pollution in southern Hebei. The study results provide scientific suggestions for regional industrial structure readjustment and have great importance for achieving the integrated development goals.
Mengjiao Jiang, Jinqin Feng, Zhanqing Li, Ruiyu Sun, Yu-Tai Hou, Yuejian Zhu, Bingcheng Wan, Jianping Guo, and Maureen Cribb
Atmos. Chem. Phys., 17, 13967–13982,Short summary
Aerosol–cloud interactions have been recognized as playing an important role in precipitation. As a benchmark evaluation of model results that exclude aerosol effects, the operational precipitation forecast (before any aerosol effects included) is evaluated using multiple datasets with the goal of determining if there is any link between the model bias and aerosol loading. The forecast model overestimates light and underestimates heavy rain. Aerosols suppress light rain and enhance heavy rain.
Yucong Miao, Jianping Guo, Shuhua Liu, Huan Liu, Zhanqing Li, Wanchun Zhang, and Panmao Zhai
Atmos. Chem. Phys., 17, 3097–3110,Short summary
Three synoptic patterns associated with heavy aerosol pollution in Beijing were identified using an objective classification approach. Relationships between synoptic patterns, aerosol pollution, and boundary layer height in Beijing during summer were revealed as well. Further, factors/mechanisms leading to the low BLHs in Beijing were unraveled. The key findings have implications for understanding the crucial roles that meteorological factors play in forecasting aerosol pollution in Beijing.
Jianping Guo, Yucong Miao, Yong Zhang, Huan Liu, Zhanqing Li, Wanchun Zhang, Jing He, Mengyun Lou, Yan Yan, Lingen Bian, and Panmao Zhai
Atmos. Chem. Phys., 16, 13309–13319,Short summary
The large-scale PBL climatology from sounding observations is still lacking in China. This work investigated the BLH characterization at diurnal, monthly and seasonal timescales throughout China, showing large geographic and meteorological dependences. BLH is, on average, negatively (positively) associated with the surface pressure and lower tropospheric stability (wind speed and temperature). Cloud tends to suppress the development of the PBL, which has implications for air quality forecasts.
Wanchun Zhang, Jianping Guo, Yucong Miao, Huan Liu, Yong Zhang, Zhengqiang Li, and Panmao Zhai
Atmos. Chem. Phys., 16, 9951–9963,Short summary
The PBL height retrieval from CALIOP aboard CALIPSO can significantly complement the traditional ground-based methods, which is only for one site. Our study, to our current knowledge, is the first intercomparison study of PBLH on a large scale using long-term radiosonde observations in China. Three matchup schemes were proposed based on the position of radiosondes relative to CALIPSO ground tracks in China. Results indicate that CALIOP is promising for reliable PBLH retrievals.
Yahui Che, Yong Xue, Linlu Mei, Jie Guang, Lu She, Jianping Guo, Yincui Hu, Hui Xu, Xingwei He, Aojie Di, and Cheng Fan
Atmos. Chem. Phys., 16, 9655–9674,Short summary
Remotely sensed data could provide continuous spatial coverage of aerosol property over the pan-Eurasian area for PEEX program. The AATSR data can be used to retrieve aerosol optical depth (AOD). The Aerosol_cci project provides users with three AOD retrieval algorithms for AATSR data. Because China is vast in territory and has great differences in terms of land surfaces, the combination of the AERONET and CARSNET data can validate the Level 2 AOD products from AATSR data more comprehensively.
Y. Q. Yang, J. Z. Wang, S. L. Gong, X. Y. Zhang, H. Wang, Y. Q. Wang, J. Wang, D. Li, and J. P. Guo
Atmos. Chem. Phys., 16, 1353–1364,Short summary
A new model, PLAM/h, has been developed and used in near-real-time air quality forecasts by considering both meteorology and pollutant emissions, based on the two-dimensional probability density function diagnosis model for emissions. The results show that combining the influence of regular meteorological conditions and emission factors together in the PLAM/h parameterization scheme is very effective in improving the forecasting ability for fog-haze weather in North China.
Related subject area
Subject: Aerosols | Research Activity: Atmospheric Modelling | Altitude Range: Troposphere | Science Focus: Physics (physical properties and processes)Intraseasonal variation of the northeast Asian anomalous anticyclone and its impacts on PM2.5 pollution in the North China Plain in early winterInverse modeling of the 2021 spring super dust storms in East AsiaCausal influences of El Niño–Southern Oscillation on global dust activitiesFormation, radiative forcing, and climatic effects of severe regional hazeAdvances in air quality research – current and emerging challengesLarge-eddy-simulation study on turbulent particle deposition and its dependence on atmospheric-boundary-layer stabilityAerosol indirect effects in complex-orography areas: a numerical study over the Great Alpine RegionModelling the size distribution of aggregated volcanic ash and implications for operational atmospheric dispersion modellingThe effect of BC on aerosol–boundary layer feedback: potential implications for urban pollution episodesRelative importance of high-latitude local and long-range-transported dust for Arctic ice-nucleating particles and impacts on Arctic mixed-phase cloudsTechnical note: Dispersion of cooking-generated aerosols from an urban street canyonComparison of six approaches to predicting droplet activation of surface active aerosol – Part 1: moderately surface active organicsThe contribution of coral-reef-derived dimethyl sulfide to aerosol burden over the Great Barrier Reef: a modelling studyDevelopment and application of a street-level meteorology and pollutant tracking system (S-TRACK)How well do the CMIP6 models simulate dust aerosols?Input-adaptive linear mixed-effects model for estimating alveolar lung-deposited surface area (LDSA) using multipollutant datasetsSimulated impacts of vertical distributions of black carbon aerosol on meteorology and PM2.5 concentrations in Beijing during severe haze eventsData assimilation of volcanic aerosol observations using FALL3D+PDAFSimulation of the effects of low-volatility organic compounds on aerosol number concentrations in EuropeNew particle formation event detection with Mask R-CNNContribution of traffic-originated nanoparticle emissions to regional and local aerosol levelsReassessment of the radiocesium resuspension flux from contaminated ground surfaces in eastern JapanDuff burning from wildfires in a moist region: different impacts on PM2.5 and ozoneAssimilating spaceborne lidar dust extinction can improve dust forecastsAssessing the value meteorological ensembles add to dispersion modelling using hypothetical releasesEffects of oligomerization and decomposition on the nanoparticle growth: a model studyThe role of anthropogenic aerosols in the anomalous cooling from 1960 to 1990 in the CMIP6 Earth system modelsConstant flux layers with gravitational settling: links to aerosols, fog and deposition velocitiesExamination of aerosol impacts on convective clouds and precipitation in two metropolitan areas in East Asia; how varying depths of convective clouds between the areas diversify those aerosol effects?Combining POLDER-3 satellite observations and WRF-Chem numerical simulations to derive biomass burning aerosol properties over the southeast Atlantic regionIs the Atlantic Ocean driving the recent variability in South Asian dust?Molecular-scale description of interfacial mass transfer in phase-separated aqueous secondary organic aerosolTropospheric warming over the North Indian Ocean caused by the South Asian anthropogenic aerosols: possible implicationsExploring the uncertainties in the aviation soot–cirrus effectReduced effective radiative forcing from cloud–aerosol interactions (ERFaci) with improved treatment of early aerosol growth in an Earth system modelHyperfine-resolution mapping of on-road vehicle emissions with comprehensive traffic monitoring and an intelligent transportation systemLess atmospheric radiative heating by dust due to the synergy of coarser size and aspherical shapeAir quality deterioration episode associated with a typhoon over the complex topographic environment in central TaiwanImpact of modified turbulent diffusion of PM2.5 aerosol in WRF-Chem simulations in eastern ChinaWhat rainfall rates are most important to wet removal of different aerosol types?A weather regime characterisation of winter biomass aerosol transport from southern Africa15-year variability of desert dust optical depth on global and regional scalesDipole pattern of summer ozone pollution in the east of China and its connection with climate variabilityAerosol absorption in global models from AeroCom phase IIIA black carbon peak and its sources in the free troposphere of Beijing induced by cyclone lifting and transport from central ChinaCompeting effects of aerosol reductions and circulation changes for future improvements in Beijing hazeUnderstanding the surface temperature response and its uncertainty to CO2, CH4, black carbon, and sulfateSurface deposition of marine fog and its treatment in the Weather Research and Forecasting (WRF) modelAssessing the potential efficacy of marine cloud brightening for cooling Earth using a simple heuristic modelAerosol effects on electrification and lightning discharges in a multicell thunderstorm simulated by the WRF-ELEC model
Xiadong An, Wen Chen, Peng Hu, Shangfeng Chen, and Lifang Sheng
Atmos. Chem. Phys., 22, 6507–6521,Short summary
The intraseasonal NAAA usually establishes quickly on day −3 with a life span of 8 days. Further results revealed that the probability of regional PM2.5 pollution related to the NAAA for at least 2 days in the NCP is 80% in NDJ period 2000–2021. Particularly, air quality in the NCP tends to deteriorate on day 2 prior to the peak day of the NAAA and reaches a peak on day −1 with a life cycle of 4 days. The corresponding meteorological conditions support these conclusions.
Jianbing Jin, Mijie Pang, Arjo Segers, Wei Han, Li Fang, Baojie Li, Haochuan Feng, Hai Xiang Lin, and Hong Liao
Atmos. Chem. Phys., 22, 6393–6410,Short summary
Super dust storms reappeared in East Asia last spring after being absent for one and a half decades. Accurate simulation of such super sandstorms is valuable, but challenging due to imperfect emissions. In this study, the emissions of these dust storms are estimated by assimilating multiple observations. The results reveal that emissions originated from both China and Mongolia. However, for northern China, long-distance transport from Mongolia contributes much more dust than Chinese deserts.
Thanh Le and Deg-Hyo Bae
Atmos. Chem. Phys., 22, 5253–5263,Short summary
Here we assess the response of dust activities to El Niño–Southern Oscillation (ENSO) over the 1850–2014 period using climate model outputs. Our results show that ENSO is an important driver of dust deposition and dust transportation with high consensus across models. However, the results indicate that ENSO is unlikely to show causal impacts on dust emissions of major dust sources. This study allows us to obtain further understanding of the linkages between ENSO and dust cycle at a global scale.
Yun Lin, Yuan Wang, Bowen Pan, Jiaxi Hu, Song Guo, Misti Levy Zamora, Pengfei Tian, Qiong Su, Yuemeng Ji, Jiayun Zhao, Mario Gomez-Hernandez, Min Hu, and Renyi Zhang
Atmos. Chem. Phys., 22, 4951–4967,Short summary
Severe regional haze events, which are characterized by exceedingly high levels of fine particulate matter (PM), occur frequently in many developing countries (such as China and India), with profound implications for human health, weather, and climate. Our work establishes a synthetic view for the dominant regional features during severe haze events, unraveling rapid in situ PM production and inefficient transport, both of which are amplified by atmospheric stagnation.
Ranjeet S. Sokhi, Nicolas Moussiopoulos, Alexander Baklanov, John Bartzis, Isabelle Coll, Sandro Finardi, Rainer Friedrich, Camilla Geels, Tiia Grönholm, Tomas Halenka, Matthias Ketzel, Androniki Maragkidou, Volker Matthias, Jana Moldanova, Leonidas Ntziachristos, Klaus Schäfer, Peter Suppan, George Tsegas, Greg Carmichael, Vicente Franco, Steve Hanna, Jukka-Pekka Jalkanen, Guus J. M. Velders, and Jaakko Kukkonen
Atmos. Chem. Phys., 22, 4615–4703,Short summary
This review of air quality research focuses on developments over the past decade. The article considers current and future challenges that are important from air quality research and policy perspectives and highlights emerging prominent gaps of knowledge. The review also examines how air pollution management needs to adapt to new challenges and makes recommendations to guide the direction for future air quality research within the wider community and to provide support for policy.
Xin Yin, Cong Jiang, Yaping Shao, Ning Huang, and Jie Zhang
Atmos. Chem. Phys., 22, 4509–4522,Short summary
Through a series of numerical experiments using the large-eddy-simulation model, we have developed an improved particle deposition scheme that takes into account transient wind shear fluctuations. Statistical analysis of the simulation results shows that the shear stress can be well approximated by a Weibull distribution and that the new scheme provides more accurate predictions than the conventional scheme, particularly under weak wind conditions and strong convective atmospheric conditions.
Anna Napoli, Fabien Desbiolles, Antonio Parodi, and Claudia Pasquero
Atmos. Chem. Phys., 22, 3901–3909,Short summary
Aerosols are liquid or solid particles suspended in the air that can interact with radiation and clouds, modifying the meteoclimatic conditions. Using an atmospheric model, we study the climatological impact of aerosols through their effects on clouds in the Alps, a region characterized by high pollution levels in the densely populated surrounding flatlands. Results show that cloud cover, temperature, and precipitation are affected by aerosols, and the response varies with elevation and season.
Frances Beckett, Eduardo Rossi, Benjamin Devenish, Claire Witham, and Costanza Bonadonna
Atmos. Chem. Phys., 22, 3409–3431,Short summary
As volcanic ash is transported through the atmosphere, it may collide and stick together to form aggregates. Neglecting the process of aggregation in atmospheric dispersion models could lead to inaccurate forecasts used by civil aviation for hazard assessment. We developed an aggregation scheme for use with the model NAME, which is used by the London Volcanic Ash Advisory Centre. Using our scheme, we investigate the impact of aggregation on simulations of the 2010 Eyjafjallajökull ash cloud.
Jessica Slater, Hugh Coe, Gordon McFiggans, Juha Tonttila, and Sami Romakkaniemi
Atmos. Chem. Phys., 22, 2937–2953,Short summary
This paper shows the specific impact of black carbon (BC) on the aerosol–planetary boundary layer (PBL) feedback and its influence on a Beijing haze episode. Overall, this paper shows that strong temperature inversions prevent BC heating within the PBL from significantly increasing PBL height, while BC above the PBL suppresses PBL development significantly through the day. From this we suggest a method by which both locally and regionally emitted BC may impact urban pollution episodes.
Yang Shi, Xiaohong Liu, Mingxuan Wu, Xi Zhao, Ziming Ke, and Hunter Brown
Atmos. Chem. Phys., 22, 2909–2935,Short summary
We perform a modeling study to evaluate the contribution to Arctic dust loading and ice-nucleating particle (INP) population from high-latitude local and low-latitude dust. High-latitude dust has a large contribution in the lower troposphere, while low-latitude dust dominates the upper troposphere. The high-latitude dust INPs result in a net cooling effect on the Arctic surface by glaciating mixed-phase clouds. Our results highlight the contribution of high-latitude dust to the Arctic climate.
Shang Gao, Mona Kurppa, Chak K. Chan, and Keith Ngan
Atmos. Chem. Phys., 22, 2703–2726,Short summary
The contribution of cooking emissions to organic aerosols may exceed that of motor vehicles. However, little is known about how cooking-generated aerosols evolve in the outdoor environment. In this paper, we present a numerical study of the dispersion of cooking emissions. For plausible choices of the emission strength, cooking can yield much higher concentrations than traffic. This has important implications for public health and city planning.
Sampo Vepsäläinen, Silvia M. Calderón, Jussi Malila, and Nønne L. Prisle
Atmos. Chem. Phys., 22, 2669–2687,Short summary
Atmospheric aerosols act as seeds for cloud formation. Many aerosols contain surface active material that accumulates at the surface of growing droplets. This can affect cloud droplet activation, but the broad significance of the effect and the best way to model it are still debated. We compare predictions of six different model approaches to surface activity of organic aerosols and find significant differences between the models, especially with large fractions of organics in the dry particles.
Sonya L. Fiddes, Matthew T. Woodhouse, Steve Utembe, Robyn Schofield, Simon P. Alexander, Joel Alroe, Scott D. Chambers, Zhenyi Chen, Luke Cravigan, Erin Dunne, Ruhi S. Humphries, Graham Johnson, Melita D. Keywood, Todd P. Lane, Branka Miljevic, Yuko Omori, Alain Protat, Zoran Ristovski, Paul Selleck, Hilton B. Swan, Hiroshi Tanimoto, Jason P. Ward, and Alastair G. Williams
Atmos. Chem. Phys., 22, 2419–2445,Short summary
Coral reefs have been found to produce the climatically relevant chemical compound dimethyl sulfide (DMS). It has been suggested that corals can modify their environment via the production of DMS. We use an atmospheric chemistry model to test this theory at a regional scale for the first time. We find that it is unlikely that coral-reef-derived DMS has an influence over local climate, in part due to the proximity to terrestrial and anthropogenic aerosol sources.
Huan Zhang, Sunling Gong, Lei Zhang, Jingwei Ni, Jianjun He, Yaqiang Wang, Xu Wang, Lixin Shi, Jingyue Mo, Huabing Ke, and Shuhua Lu
Atmos. Chem. Phys., 22, 2221–2236,Short summary
This study established a multi-model simulation system for street-level circulation and pollutant tracking and applied to real building scenarios and atmospheric conditions. Results showed that for a particular site the potential contribution ratio varies with the height of the site, with a peak not at the ground but at a certain height. This work is of significance for urban planning and improvement of urban air quality.
Alcide Zhao, Claire L. Ryder, and Laura J. Wilcox
Atmos. Chem. Phys., 22, 2095–2119,Short summary
The CMIP6 models' simulated dust processes are getting more uncertain as models become more sophisticated. Of particular challenge are the links between dust cycles and optical properties, and we recommend more detailed output relating to dust cycles in future intercomparison projects to constrain such links. Also, models struggle to capture certain key regional dust processes such as dust accumulation along the slope of the Himalayas and dust seasonal cycles in North China and North America.
Pak Lun Fung, Martha A. Zaidan, Jarkko V. Niemi, Erkka Saukko, Hilkka Timonen, Anu Kousa, Joel Kuula, Topi Rönkkö, Ari Karppinen, Sasu Tarkoma, Markku Kulmala, Tuukka Petäjä, and Tareq Hussein
Atmos. Chem. Phys., 22, 1861–1882,Short summary
We developed an input-adaptive mixed-effects model, which was automatised to select the best combination of input variables, including up to three fixed effect variables and three time indictors as random effect variables. We tested the model to estimate lung-deposited surface area (LDSA), which correlates well with human health. The results show the inclusion of time indicators improved the sensitivity and the accuracy of the model so that it could serve as a network of virtual sensors.
Donglin Chen, Hong Liao, Yang Yang, Lei Chen, Delong Zhao, and Deping Ding
Atmos. Chem. Phys., 22, 1825–1844,Short summary
The black carbon (BC) vertical profile plays a critical role in BC–meteorology interaction, which also influences PM2.5 concentrations. More BC mass was assigned into high altitudes (above 1000 m) in the model, which resulted in a stronger cooling effect near the surface, a larger temperature inversion below 421 m, more reductions in PBLH, and a larger increase in near-surface PM2.5 in the daytime caused by the direct radiative effect of BC.
Leonardo Mingari, Arnau Folch, Andrew T. Prata, Federica Pardini, Giovanni Macedonio, and Antonio Costa
Atmos. Chem. Phys., 22, 1773–1792,Short summary
We present a new implementation of an ensemble-based data assimilation method to improve forecasting of volcanic aerosols. This system can be efficiently integrated into operational workflows by exploiting high-performance computing resources. We found a dramatic improvement of forecast quality when satellite retrievals are continuously assimilated. Management of volcanic risk and reduction of aviation impacts can strongly benefit from this research.
David Patoulias and Spyros N. Pandis
Atmos. Chem. Phys., 22, 1689–1706,Short summary
Our simulations indicate that the recently identified production and subsequent condensation effect of extremely low-volatility organic compounds have a smaller-than-expected effect on the total concentration of atmospheric particles. On the other hand, the oxidation of intermediate-volatility organic compounds leads to decreases in the ultrafine-particle concentrations. These results improve our understanding of the links between secondary organic aerosol formation and ultrafine particles.
Peifeng Su, Jorma Joutsensaari, Lubna Dada, Martha Arbayani Zaidan, Tuomo Nieminen, Xinyang Li, Yusheng Wu, Stefano Decesari, Sasu Tarkoma, Tuukka Petäjä, Markku Kulmala, and Petri Pellikka
Atmos. Chem. Phys., 22, 1293–1309,Short summary
We regarded the banana shapes in the surface plots as a special kind of object (similar to cats) and applied an instance segmentation technique to automatically identify the new particle formation (NPF) events (especially the strongest ones), in addition to their growth rates, start times, and end times. The automatic method generalized well on datasets collected in different sites, which is useful for long-term data series analysis and obtaining statistical properties of NPF events.
Miska Olin, David Patoulias, Heino Kuuluvainen, Jarkko V. Niemi, Topi Rönkkö, Spyros N. Pandis, Ilona Riipinen, and Miikka Dal Maso
Atmos. Chem. Phys., 22, 1131–1148,Short summary
An emission factor particle size distribution was determined from the measurements at an urban traffic site. It was used in updating a pre-existing emission inventory, and regional modeling was performed after the update. Emission inventories typically underestimate nanoparticle emissions due to challenges in determining them with high certainty. This update reveals that the simulated aerosol levels have previously been underestimated especially for urban areas and for sub-50 nm particles.
Mizuo Kajino, Akira Watanabe, Masahide Ishizuka, Kazuyuki Kita, Yuji Zaizen, Takeshi Kinase, Rikuya Hirai, Kakeru Konnai, Akane Saya, Kazuki Iwaoka, Yoshitaka Shiroma, Hidenao Hasegawa, Naofumi Akata, Masahiro Hosoda, Shinji Tokonami, and Yasuhito Igarashi
Atmos. Chem. Phys., 22, 783–803,Short summary
Using a numerical model and observations of surface concentration and depositions, the current study provides quantitative assessments of resuspension, transport, and deposition of radio-Cs in eastern Japan in 2013, which was once deposited to the ground surface after the Fukushima nuclear accident. The areal mean resuspension rate of radio-Cs from the ground to the air is estimated as 0.96 % per year, which is equivalent to 1–10 % of the decreasing rate of the ambient gamma dose in Fukushima.
Aoxing Zhang, Yongqiang Liu, Scott Goodrick, and Marcus D. Williams
Atmos. Chem. Phys., 22, 597–624,Short summary
Duff is decomposed forest fuel under ground. Duff burning often occurs at the smoldering phase with low intensity and long periods, which has little impact on regional air quality. However, there is increasing evidence for duff burning during flaming phases. This study simulates the air quality impacts of duff burning during flaming phases in the southeastern US using a regional air quality model. The results indicate the important contributions of such burning to regional PM2.5 concentrations.
Jerónimo Escribano, Enza Di Tomaso, Oriol Jorba, Martina Klose, Maria Gonçalves Ageitos, Francesca Macchia, Vassilis Amiridis, Holger Baars, Eleni Marinou, Emmanouil Proestakis, Claudia Urbanneck, Dietrich Althausen, Johannes Bühl, Rodanthi-Elisavet Mamouri, and Carlos Pérez García-Pando
Atmos. Chem. Phys., 22, 535–560,Short summary
We explore the benefits and consistency in adding lidar dust observations in a dust optical depth assimilation. We show that adding lidar data to a dust optical depth assimilation has valuable benefits and the dust analysis improves. We discuss the impact of the narrow satellite footprint of the lidar dust observations on the assimilation.
Susan J. Leadbetter, Andrew R. Jones, and Matthew C. Hort
Atmos. Chem. Phys., 22, 577–596,Short summary
In this study we look at the ability of meteorological ensembles (multiple realisations of the meteorological data) to provide information about the uncertainty in the dispersion model predictions. Statistical measures are used to evaluate the model predictions, and these show that on average the ensemble predictions outperform the non-ensemble predictions.
Arto Heitto, Kari Lehtinen, Tuukka Petäjä, Felipe Lopez-Hilfiker, Joel A. Thornton, Markku Kulmala, and Taina Yli-Juuti
Atmos. Chem. Phys., 22, 155–171,Short summary
For atmospheric aerosol particles to take part in cloud formation, they need to be at least a few tens of nanometers in diameter. By using a particle condensation model, we investigated how two types of chemical reactions, oligomerization and decomposition, of organic molecules inside the particle may affect the growth of secondary aerosol particles to these sizes. We show that the effect is potentially significant, which highlights the importance of increasing understanding of these processes.
Jie Zhang, Kalli Furtado, Steven T. Turnock, Jane P. Mulcahy, Laura J. Wilcox, Ben B. Booth, David Sexton, Tongwen Wu, Fang Zhang, and Qianxia Liu
Atmos. Chem. Phys., 21, 18609–18627,Short summary
The CMIP6 ESMs systematically underestimate TAS anomalies in the NH midlatitudes, especially from 1960 to 1990. The anomalous cooling is concurrent in time and space with anthropogenic SO2 emissions. The spurious drop in TAS is attributed to the overestimated aerosol concentrations. The aerosol forcing sensitivity cannot well explain the inter-model spread of PHC biases. And the cloud-amount term accounts for most of the inter-model spread in aerosol forcing sensitivity.
Peter A. Taylor
Atmos. Chem. Phys., 21, 18263–18269,Short summary
Atmospheric aerosols including fog droplets can be deposited on the ground or on water surfaces. This is due to both gravitational settling and turbulent impaction. A simple model of this combined process is developed based on conventional atmospheric-boundary-layer ideas. The model suggests an alternative formulation for the treatment of gravitational settling in the deposition velocity estimations of aerosol particles and fog droplets.
Seoung Soo Lee, Jinho Choi, Goun Kim, Kyung-Ja Ha, Kyong-Hwan Seo, Junshik Um, and Youtong Zheng
Atmos. Chem. Phys. Discuss.,
Revised manuscript accepted for ACPShort summary
This study investigates how aerosols affect clouds and precipitation and how those aerosol effects vary with varying types of clouds that are characterized by cloud depth in two metropolitan areas in East Asia. As cloud depth increases, the enhancement of precipitation amount transitions to no changes in precipitation amount with increasing aerosol concentrations. This indicates that cloud depth needs to be considered for a comprehensive understanding of aerosol-cloud interactions.
Alexandre Siméon, Fabien Waquet, Jean-Christophe Péré, Fabrice Ducos, François Thieuleux, Fanny Peers, Solène Turquety, and Isabelle Chiapello
Atmos. Chem. Phys., 21, 17775–17805,Short summary
For the first time, we accurately modelled the optical properties of the biomass burning aerosols (BBA) observed over the Southeast Atlantic region during their transport above clouds and over their source regions, combining a meteorology coupled with chemistry model (WRF-Chem) with innovative satellite absorbing aerosol retrievals (POLDER-3). Our results suggest a low but non-negligible brown carbon fraction (3 %) for the chemical composition of the BBA plumes observed over the source regions.
Priyanka Banerjee, Sreedharan Krishnakumari Satheesh, and Krishnaswamy Krishna Moorthy
Atmos. Chem. Phys., 21, 17665–17685,Short summary
We show that the Atlantic Ocean is the major driver of interannual variability in dust over South Asia since the second decade of the 21st century. This is a shift from the previously important role played by the Pacific Ocean in controlling dust over this region. Following the end of the recent global warming hiatus, anomalies of the North Atlantic sea surface temperature have remotely invoked a weakening of the South Asian monsoon and a strengthening of the dust-bearing northwesterlies.
Mária Lbadaoui-Darvas, Satoshi Takahama, and Athanasios Nenes
Atmos. Chem. Phys., 21, 17687–17714,Short summary
Aerosol–cloud interactions constitute the most uncertain contribution to climate change. The uptake kinetics of water by aerosol is a central process of cloud droplet formation, yet its molecular-scale mechanism is unknown. We use molecular simulations to study this process for phase-separated organic particles. Our results explain the increased cloud condensation activity of such particles and can be generalized over various compositions, thus possibly serving as a basis for future models.
Suvarna Fadnavis, Prashant Chavan, Akash Joshi, Sunil Sonbawne, Asutosh Acharya, Panuganti Devara, Alexandru Rap, and Rolf Müller
Atmos. Chem. Phys. Discuss.,
Revised manuscript accepted for ACPShort summary
We show implications of the transport pathways of South Asian aerosols during spring. Our simulations show that large numbers of South Asian anthropogenic aerosols are transported to the North Indian Ocean in spring. These aerosols enhance tropospheric heating, evaporation, convection, and ascending winds over the Arabian Sea. These aerosols provide positive feedback leading to enhanced transport of aerosol and water vapor to the UTLS. In the stratosphere, water vapor are transported globally.
Mattia Righi, Johannes Hendricks, and Christof Gerhard Beer
Atmos. Chem. Phys., 21, 17267–17289,Short summary
A global climate model is applied to simulate the impact of aviation soot on natural cirrus clouds. A large number of numerical experiments are performed to analyse how the quantification of the resulting climate impact is affected by known uncertainties. These concern the ability of aviation soot to nucleate ice and the role of model dynamics. Our results show that both aspects are important for the quantification of this effect and that discrepancies among different model studies still exist.
Sara Marie Blichner, Moa Kristina Sporre, and Terje Koren Berntsen
Atmos. Chem. Phys., 21, 17243–17265,Short summary
In this study we quantify how a new way of modeling the formation of new particles in the atmosphere affects the estimated cooling from aerosol–cloud interactions since pre-industrial times. Our improved scheme merges two common approaches to aerosol modeling: a sectional scheme for treating early growth and the pre-existing modal scheme in NorESM. We find that the cooling from aerosol–cloud interactions since pre-industrial times is reduced by 10 % when the new scheme is used.
Linhui Jiang, Yan Xia, Lu Wang, Xue Chen, Jianjie Ye, Tangyan Hou, Liqiang Wang, Yibo Zhang, Mengying Li, Zhen Li, Zhe Song, Yaping Jiang, Weiping Liu, Pengfei Li, Daniel Rosenfeld, John H. Seinfeld, and Shaocai Yu
Atmos. Chem. Phys., 21, 16985–17002,Short summary
This paper establishes a bottom-up approach to reveal a unique pattern of urban on-road vehicle emissions at a spatial resolution 1–3 orders of magnitude higher than current inventories. The results show that the hourly average on-road vehicle emissions of CO, NOx, HC, and PM2.5 are 74 kg, 40 kg, 8 kg, and 2 kg, respectively. Integrating our traffic-monitoring-based approach with urban measurements, we could address major data gaps between urban air pollutant emissions and concentrations.
Akinori Ito, Adeyemi A. Adebiyi, Yue Huang, and Jasper F. Kok
Atmos. Chem. Phys., 21, 16869–16891,Short summary
We improve the simulated dust properties of size-resolved dust concentration and particle shape. The improved simulation suggests much less atmospheric radiative heating near the major source regions, because of enhanced longwave warming at the surface by the synergy of coarser size and aspherical shape. Less intensified atmospheric heating could substantially modify the vertical temperature profile in Earth system models and thus has important implications for the projection of dust feedback.
Chuan-Yao Lin, Yang-Fan Sheng, Wan-Chin Chen, Charles C. K. Chou, Yi-Yun Chien, and Wen-Mei Chen
Atmos. Chem. Phys., 21, 16893–16910,Short summary
Taiwan and Hong Kong experience air quality deterioration as typhoons approach. However, the mechanism of the formation of poor air quality may differ and still not be well documented in Taiwan. The interaction between easterly typhoon circulation and Taiwan’s Central Mountain Range resulted in a lee side vortex formation. Simulation results indicated that the lee vortex and land–sea breeze, as well as the boundary layer development, were the key mechanisms.
Wenxing Jia and Xiaoye Zhang
Atmos. Chem. Phys., 21, 16827–16841,Short summary
Heavy aerosol pollution incidents have attracted much attention since 2013, but the temporal and spatial limitations of observations and the inaccuracy of simulation are a stumbling block to assessing pollution mechanisms. The correct simulation of boundary layer mixing process of pollutant is a challenge for mesoscale numerical models. We add the turbulent diffusion term of aerosol to the WRF-Chem model to prove the impact of turbulent diffusion on pollutant concentration.
Yong Wang, Wenwen Xia, and Guang J. Zhang
Atmos. Chem. Phys., 21, 16797–16816,Short summary
This study developed a novel approach to detect what rainfall rates climatologically are most efficient for wet removal of different aerosol types and applied it to a global climate model (GCM). Results show that light rain has disproportionate control on aerosol wet scavenging, with distinct rain rates for different aerosol sizes. The approach can be applied to other GCMs to better understand the aerosol wet scavenging by rainfall, which is important to better simulate aerosols.
Marco Gaetani, Benjamin Pohl, Maria del Carmen Alvarez Castro, Cyrille Flamant, and Paola Formenti
Atmos. Chem. Phys., 21, 16575–16591,Short summary
During the dry austral winter, biomass fires in tropical Africa emit large amounts of smoke in the atmosphere, with large impacts on climate and air quality. The study of the relationship between atmospheric circulation and smoke transport shows that midlatitude atmospheric disturbances may deflect the smoke from tropical Africa towards southern Africa. Understanding the distribution of the smoke in the region is crucial for climate modelling and air quality monitoring.
Stavros-Andreas Logothetis, Vasileios Salamalikis, Antonis Gkikas, Stelios Kazadzis, Vassilis Amiridis, and Andreas Kazantzidis
Atmos. Chem. Phys., 21, 16499–16529,Short summary
This study investigates the temporal trends of dust optical depth (DOD; 550 nm) on global, regional and seasonal scales over a 15-year period (2003–2017) using the MIDAS (ModIs Dust AeroSol) dataset. The findings of this study revealed that the DOD was increased across the central Sahara and the Arabian Peninsula, with opposite trends over the eastern and western Sahara, the Thar and Gobi deserts, in the Bodélé Depression, and in the southern Mediterranean.
Xiaoqing Ma and Zhicong Yin
Atmos. Chem. Phys., 21, 16349–16361,Short summary
Severe ozone pollution frequently occurred in the east of China and obviously damages human health. The meteorological conditions effectively affect the variations in ozone pollution by modulating the natural emissions of ozone precursors and photochemical reactions in the atmosphere. In this study, a south–north dipole pattern of summer-mean ozone concentration in the east of China was identified, and its connections with preceding climate variability at different latitudes were also examined.
Maria Sand, Bjørn H. Samset, Gunnar Myhre, Jonas Gliß, Susanne E. Bauer, Huisheng Bian, Mian Chin, Ramiro Checa-Garcia, Paul Ginoux, Zak Kipling, Alf Kirkevåg, Harri Kokkola, Philippe Le Sager, Marianne T. Lund, Hitoshi Matsui, Twan van Noije, Dirk J. L. Olivié, Samuel Remy, Michael Schulz, Philip Stier, Camilla W. Stjern, Toshihiko Takemura, Kostas Tsigaridis, Svetlana G. Tsyro, and Duncan Watson-Parris
Atmos. Chem. Phys., 21, 15929–15947,Short summary
Absorption of shortwave radiation by aerosols can modify precipitation and clouds but is poorly constrained in models. A total of 15 different aerosol models from AeroCom phase III have reported total aerosol absorption, and for the first time, 11 of these models have reported in a consistent experiment the contributions to absorption from black carbon, dust, and organic aerosol. Here, we document the model diversity in aerosol absorption.
Zhenbin Wang, Bin Zhu, Hanqing Kang, Wen Lu, Shuqi Yan, Delong Zhao, Weihang Zhang, and Jinhui Gao
Atmos. Chem. Phys., 21, 15555–15567,Short summary
In this paper, by using WRF-Chem with a black carbon (BC) tagging technique, we investigate the formation mechanism and regional sources of a BC peak in the free troposphere observed by aircraft flights. Local sources dominated BC from the surface to about 700 m (78.5 %), while the BC peak in the free troposphere was almost entirely imported from external sources (99.8 %). Our results indicate that cyclone systems can quickly lift BC up to the free troposphere, as well as extend its lifetime.
Liang Guo, Laura J. Wilcox, Massimo Bollasina, Steven T. Turnock, Marianne T. Lund, and Lixia Zhang
Atmos. Chem. Phys., 21, 15299–15308,Short summary
Severe haze remains serious over Beijing despite emissions decreasing since 2008. Future haze changes in four scenarios are studied. The pattern conducive to haze weather increases with the atmospheric warming caused by the accumulation of greenhouse gases. However, the actual haze intensity, measured by either PM2.5 or optical depth, decreases with aerosol emissions. We show that only using the weather pattern index to predict the future change of Beijing haze is insufficient.
Kalle Nordling, Hannele Korhonen, Jouni Räisänen, Antti-Ilari Partanen, Bjørn H. Samset, and Joonas Merikanto
Atmos. Chem. Phys., 21, 14941–14958,Short summary
Understanding the temperature responses to different climate forcing agents, such as greenhouse gases and aerosols, is crucial for understanding future regional climate changes. In climate models, the regional temperature responses vary for all forcing agents, but the causes of this variability are poorly understood. For all forcing agents, the main component contributing to variance in regional surface temperature responses between the climate models is the clear-sky longwave emissivity.
Peter A. Taylor, Zheqi Chen, Li Cheng, Soudeh Afsharian, Wensong Weng, George A. Isaac, Terry W. Bullock, and Yongsheng Chen
Atmos. Chem. Phys., 21, 14687–14702,Short summary
In marine fog, droplets will impact the water surface, collide and coalesce. This removal process is underestimated or ignored in many fog and weather forecast models. A new atmospheric boundary layer approach is proposed and tested in a standard weather forecast model (Weather Research and Forecasting, WRF). New profile measurements through marine fog layers are suggested.
Atmos. Chem. Phys., 21, 14507–14533,Short summary
A simple model is described to assess the potential for increasing solar reflection by augmenting the aerosol population below marine low clouds, which increases the concentration of cloud droplets. The model is used to predict global cooling from marine cloud brightening climate intervention as a function of the quantity, size, and lifetime of salt particles injected per sprayer, the number of sprayers deployed, the cloud updraft speed, and unperturbed aerosol size distribution.
Mengyu Sun, Dongxia Liu, Xiushu Qie, Edward R. Mansell, Yoav Yair, Alexandre O. Fierro, Shanfeng Yuan, Zhixiong Chen, and Dongfang Wang
Atmos. Chem. Phys., 21, 14141–14158,Short summary
By acting as cloud condensation nuclei (CCN), increasing aerosol loading tends to enhance lightning activity through microphysical processes. We investigated the aerosol effects on the development of a thunderstorm. A two-moment bulk microphysics scheme and bulk lightning model were coupled in the WRF Model to simulate a multicell thunderstorm. Sensitivity experiments show that the enhancement of lightning activity under polluted conditions results from an increasing ice crystal number.
Chan, E. Y. Y., Goggins, W. B., Kim, J. J., and Griffiths, S. M.: A study of intracity variation of temperature-related mortality and socioeconomic status among the Chinese population in Hong Kong, J. Epidemiol. Commun. H., 66, 322–327, https://doi.org/10.1136/jech.2008.085167, 2012.
Chen, X., Shao, S., Tian, Z., Xie, Z., and Yin, P.: Impacts of air pollution and its spatial spillover effect on public health based on China's big data sample, J. Clean. Prod., 142, 915–925, https://doi.org/10.1016/j.jclepro.2016.02.119, 2017.
Climatological Information Services: Climatological Database, available at: https://www.hko.gov.hk/en/cis/climat.htm, last access: 21 May 2021.
Environmental Protection Interactive Centre: Inquire and Download Air Quality Monitoring Data, available at: https://cd.epic.epd.gov.hk/EPICDI/air/station/?lang=en, last access: 21 May 2021.
Fan, S., Wang, B., Tesche, M., Engelmann, R., Althausen, A., Liu, J., Zhu, W., Fan, Q., Li, M., Ta, N., Song, L., and Leong, K.: Meteorological conditions and structures of atmospheric boundary layer in October 2004 over Pearl River Delta area, Atmos. Environ., 42, 6174–6186, https://doi.org/10.1016/j.atmosenv.2008.01.067, 2008.
Fan, S. J., Fan, Q., Yu, W., Luo, X. Y., Wang, B. M., Song, L. L., and Leong, K. L.: Atmospheric boundary layer characteristics over the Pearl River Delta, China, during the summer of 2006: measurement and model results, Atmos. Chem. Phys., 11, 6297–6310, https://doi.org/10.5194/acp-11-6297-2011, 2011.
Founda, D. and Santamouris, M.: Synergies between Urban Heat Island and Heat Waves in Athens (Greece), during an extremely hot summer (2012), Sci. Rep., 7, 10973, https://doi.org/10.1038/s41598-017-11407-6, 2017.
Freychet, N., Tett, S., Wang, J., and Hegerl, G.: Summer heat waves over Eastern China: dynamical processes and trend attribution, Environ. Res. Lett., 12, 024015, https://doi.org/10.1088/1748-9326/aa5ba3, 2017.
Gong, C. and Liao, H.: A typical weather pattern for ozone pollution events in North China, Atmos. Chem. Phys., 19, 13725–13740, https://doi.org/10.5194/acp-19-13725-2019, 2019.
Grell, G. A., Peckham, S. E., Schmitz, R., McKeen, S. A., Frost, G., Skamarock, W. C., and Eder, B.: Fully coupled “online” chemistry within the WRF model, Atmos. Environ., 39, 6957–6975, https://doi.org/10.1016/j.atmosenv.2005.04.027, 2005.
Gu, Y., Wong, T. W., Law, C. K., Dong, G. H., Ho, K. F., Yang, Y., and Yim, S. H. L.: Impacts of sectoral emissions in China and the implications: air quality, public health, crop production, and economic costs, Environ. Res. Lett., 13, 084008, https://doi.org/10.1088/1748-9326/aad138, 2018.
Guenther, A., Karl, T., Harley, P., Wiedinmyer, C., Palmer, P. I., and Geron, C.: Estimates of global terrestrial isoprene emissions using MEGAN (Model of Emissions of Gases and Aerosols from Nature), Atmos. Chem. Phys., 6, 3181–3210, https://doi.org/10.5194/acp-6-3181-2006, 2006.
Guo, J., Deng, M., Lee, S. S., Wang, F., Li, Z., Zhai, P., Liu, H., Lv, W., Yao, W., and Li, X.: Delaying precipitation and lightning by air pollution over the Pearl River Delta. Part I: Observational analyses, J. Geophys. Res.-Atmos., 121, 6472–6488, https://doi.org/10.1002/2015JD023257, 2016.
Guo, J., Liu, H., Li, Z., Rosenfeld, D., Jiang, M., Xu, W., Jiang, J. H., He, J., Chen, D., Min, M., and Zhai, P.: Aerosol-induced changes in the vertical structure of precipitation: a perspective of TRMM precipitation radar, Atmos. Chem. Phys., 18, 13329–13343, https://doi.org/10.5194/acp-18-13329-2018, 2018.
Hartigan, J. A. and Wong, M. A.: Algorithm AS 136: A K-Means Clustering Algorithm, J. R. Stat. Soc. C-Appl., 28, 100–108, https://doi.org/10.2307/2346830, 1979.
Hou, X., Chan, C. K., Dong, G. H., and Yim, S. H. L.: Impacts of transboundary air pollution and local emissions on PM2.5 pollution in the Pearl River Delta region of China and the public health, and the policy implications, Environ. Res. Lett., 14, 034005, https://doi.org/10.1088/1748-9326/aaf493, 2019.
Katsouyanni, D. K., Pantazopoulou, A., Touloumi, G., Tselepidaki, I., Moustris, K., Asimakopoulos, D., Poulopoulou, G., and Trichopoulos, D.: Evidence for Interaction between Air Pollution and High Temperature in the Causation of Excess Mortality, Arch. Environ. Health, 48, 235–242, https://doi.org/10.1080/00039896.1993.9940365, 1993.
Khafaie, M. A., Yajnik, C. S., Salvi, S. S., and Ojha, A.: Critical review of air pollution health effects with special concern on respiratory health, J. Air Poll. Health, 1, 123–136, 2016.
Lam, K. S., Wang, T. J., Wu, C. L., and Li, Y. S.: Study on an ozone episode in hot season in Hong Kong and transboundary air pollution over Pearl River Delta region of China, Atmos. Environ., 39, 1967–1977, https://doi.org/10.1016/j.atmosenv.2004.11.023, 2005.
Li, D. and Bou-Zeid, E.: Synergistic Interactions between Urban Heat Islands and Heat Waves: The Impact in Cities Is Larger than the Sum of Its Parts, J. Appl. Meteorol. Clim., 52, 2051–2064, https://doi.org/10.1175/JAMC-D-13-02.1, 2013.
Li, D., Sun, T., Liu, M., Yang, L., Wang, L., and Gao, Z.: Contrasting responses of urban and rural surface energy budgets to heat waves explain synergies between urban heat islands and heat waves, Environ. Res. Lett., 10, 054009, https://doi.org/10.1088/1748-9326/10/5/054009, 2015.
Li, H., Wang, B., Fang, X., Zhu, W., Fan, Q., Liao, Z., Liu, J., Zhang, A., and Fan, S.: Combined effect of boundary layer recirculation factor and stable energy on local air quality in the Pearl River Delta over southern China, J. Air Waste Manage., 68, 685–699, https://doi.org/10.1080/10962247.2018.1439125, 2018.
Li, M., Song, Y., Mao, Z., Liu, M., and Huang, X.: Impacts of thermal circulations induced by urbanization on ozone formation in the Pearl River Delta region, China, Atmos. Environ., 127, 382–392, https://doi.org/10.1016/j.atmosenv.2015.10.075, 2016.
Li, N., He, Q., Greenberg, J., Guenther, A., Li, J., Cao, J., Wang, J., Liao, H., Wang, Q., and Zhang, Q.: Impacts of biogenic and anthropogenic emissions on summertime ozone formation in the Guanzhong Basin, China, Atmos. Chem. Phys., 18, 7489–7507, https://doi.org/10.5194/acp-18-7489-2018, 2018.
Liu, M., Huang, Y., Ma, Z., Jin, Z., Liu, X., Wang, H., Liu, Y., Wang, J., Jantunen, M., Bi, J., and Kinney, P. L.: Spatial and temporal trends in the mortality burden of air pollution in China: 2004–2012, Environ. Int., 98, 75–81, https://doi.org/10.1016/j.envint.2016.10.003, 2017.
Liu, Z., Yim, S. H. L., Wang, C., and Lau, N. C.: The Impact of the Aerosol Direct Radiative Forcing on Deep Convection and Air Quality in the Pearl River Delta Region, Geophys. Res. Lett., 45, 4410–4418, https://doi.org/10.1029/2018GL077517, 2018.
Liu, Z., Ming, Y., Wang, L., Bollasina, M., Luo, M., Lau, N.-C., and Yim, S. H.-L.: A Model Investigation of Aerosol-Induced Changes in the East Asian Winter Monsoon, Geophys. Res. Lett., 46, 10186–10195, https://doi.org/10.1029/2019GL084228, 2019.
Liu, Z., Ming, Y., Zhao, C., Lau, N. C., Guo, J., Bollasina, M., and Yim, S. H. L.: Contribution of local and remote anthropogenic aerosols to a record-breaking torrential rainfall event in Guangdong Province, China, Atmos. Chem. Phys., 20, 223–241, https://doi.org/10.5194/acp-20-223-2020, 2020.
Lovett, G. M., Tear, T. H., Evers, D. C., Findlay, S. E. G., Cosby, B. J., Dunscomb, J. K., Driscoll, C. T., and Weathers, K. C.: Effects of air pollution on ecosystems and biological diversity in the eastern United States, Ann. N.Y. Acad. Sci., 1162, 99–135, https://doi.org/10.1111/j.1749-6632.2009.04153.x, 2009.
Luo, M., Hou, X., Gu, Y., Lau, N.-C., and Yim, S. H.-L.: Trans-boundary air pollution in a city under various atmospheric conditions, Sci. Total Environ., 618, 132–141, https://doi.org/10.1016/j.scitotenv.2017.11.001, 2018.
Matusick, G., Ruthrof, K. X., Kala, J., Brouwers, N. C., Breshears, D. D., and Hardy, G. E. S. J.: Chronic historical drought legacy exacerbates tree mortality and crown dieback during acute heatwave-compounded drought, Environ. Res. Lett., 13, 095002, https://doi.org/10.1088/1748-9326/aad8cb, 2018.
Miralles, D. G., Teuling, A. J., van Heerwaarden, C. C., and Vilà-Guerau de Arellano, J.: Mega-heatwave temperatures due to combined soil desiccation and atmospheric heat accumulation, Nat. Geosci., 7, 345–349, https://doi.org/10.1038/ngeo2141, 2014.
Mirzaei, P. A. and Haghighat, F.: Approaches to study Urban Heat Island – Abilities and limitations, Build. Environ., 45, 2192–2201, https://doi.org/10.1016/j.buildenv.2010.04.001, 2010.
Murari, K. K. and Ghosh, S.: Future Heat Wave Projections and Impacts, in: Climate Change Signals and Response: A Strategic Knowledge Compendium for India, edited by: Venkataraman, C., Mishra, T., Ghosh, S., and Karmakar, S., Springer Singapore, Singapore, 91–107, https://doi.org/10.1007/978-981-13-0280-0_6, 2019.
Nowak, D. J., Jovan, S., Branquinho, C., Augusto, S., Ribeiro, M. C., and Kretsch, C. E.: Biodiversity, air quality and human health, in: Connecting global priorities: biodiversity and human health: a state of knowledge review, 63–74, Chap. 4, World Health Organization, Geneva, Switzerland, 2015.
Ordóñez, C., Elguindi, N., Stein, O., Huijnen, V., Flemming, J., Inness, A., Flentje, H., Katragkou, E., Moinat, P., Peuch, V.-H., Segers, A., Thouret, V., Athier, G., van Weele, M., Zerefos, C. S., Cammas, J.-P., and Schultz, M. G.: Global model simulations of air pollution during the 2003 European heat wave, Atmos. Chem. Phys., 10, 789–815, https://doi.org/10.5194/acp-10-789-2010, 2010.
Panastasiou, D. K., Melas, D., and Kambezidis, H. D.: Heat waves characteristics and their relation to air quality in Athens, Global Nest J., 16, 919–928, https://doi.org/10.30955/gnj.001530, 2014.
Pearl River Delta Regional Air Quality Monitoring Report/Environmental Protection Department: available at: https://www.epd.gov.hk/epd/english/resources_pub/publications/m_report.html, last access: 21 May 2021.
Pinheiro, S. de L. L. de A., Saldiva, P. H. N., Schwartz, J., and Zanobetti, A.: Isolated and synergistic effects of PM10 and average temperature on cardiovascular and respiratory mortality, Rev. Saúde Pública, 48, 881–888, https://doi.org/10.1590/S0034-8910.2014048005218, 2014.
Qian, Z., He, Q., Lin, H.-M., Kong, L., Zhou, D., Liang, S., Zhu, Z., Liao, D., Liu, W., Bentley, C. M., Dan, J., Wang, B., Yang, N., Xu, S., Gong, J., Wei, H., Sun, H., Qin, Z., and HEI Health Review Committee: Part 2. Association of daily mortality with ambient air pollution, and effect modification by extremely high temperature in Wuhan, China, Res. Rep. Health Eff. Inst., 91–217, 2010.
Ramamurthy, P., González, J., Ortiz, L., Arend, M., and Moshary, F.: Impact of heatwave on a megacity: an observational analysis of New York City during July 2016, Environ. Res. Lett., 12, 054011, https://doi.org/10.1088/1748-9326/aa6e59, 2017.
Scortichini, M., De Sario, M., De'Donato, F. K., Davoli, M., Michelozzi, P., and Stafoggia, M.: Short-Term Effects of Heat on Mortality and Effect Modification by Air Pollution in 25 Italian Cities, Int. J. Environ. Res. Public Health, 15, 1771, https://doi.org/10.3390/ijerph15081771, 2018.
Shi, C., Nduka, I. C., Yang, Y., Huang, Y., Yao, R., Zhang, H., He, B., Xie, C., Wang, Z., and Yim, S. H. L.: Characteristics and meteorological mechanisms of transboundary air pollution in a persistent heavy PM2.5 pollution episode in Central-East China, Atmos. Environ., 223, 117239, https://doi.org/10.1016/j.atmosenv.2019.117239, 2020.
Shu, L., Wang, T., Han, H., Xie, M., Chen, P., Li, M., and Wu, H.: Summertime ozone pollution in the Yangtze River Delta of eastern China during 2013–2017: Synoptic impacts and source apportionment, Environ. Pollut., 257, 113631, https://doi.org/10.1016/j.envpol.2019.113631, 2020.
Silva, R. A., West, J. J., Lamarque, J.-F., Shindell, D. T., Collins, W. J., Dalsoren, S., Faluvegi, G., Folberth, G., Horowitz, L. W., Nagashima, T., Naik, V., Rumbold, S. T., Sudo, K., Takemura, T., Bergmann, D., Cameron-Smith, P., Cionni, I., Doherty, R. M., Eyring, V., Josse, B., MacKenzie, I. A., Plummer, D., Righi, M., Stevenson, D. S., Strode, S., Szopa, S., and Zengast, G.: The effect of future ambient air pollution on human premature mortality to 2100 using output from the ACCMIP model ensemble, Atmos. Chem. Phys., 16, 9847–9862, https://doi.org/10.5194/acp-16-9847-2016, 2016.
Skamarock, W. C. and Klemp, J. B.: A time-split nonhydrostatic atmospheric model for weather research and forecasting applications, J. Comput. Phys., 227, 3465–3485, https://doi.org/10.1016/j.jcp.2007.01.037, 2008.
Stefanon, M., D'Andrea, F., and Drobinski, P.: Heatwave classification over Europe and the Mediterranean region, Environ. Res. Lett., 7, 014023, https://doi.org/10.1088/1748-9326/7/1/014023, 2012.
Streets, D. G., Bond, T. C., Carmichael, G. R., Fernandes, S. D., Fu, Q., He, D., Klimont, Z., Nelson, S. M., Tsai, N. Y., Wang, M. Q., Woo, J.-H., and Yarber, K. F.: An inventory of gaseous and primary aerosol emissions in Asia in the year 2000, J. Geophys. Res., 108, 8809, https://doi.org/10.1029/2002JD003093, 2003.
Tan, P.-N., Steinbach, M., Karpatne, A., and Kumar, V.: Introduction to data mining, 2nd Edn., Pearson, NY, 2019.
Tong, C. H. M., Yim, S. H. L., Rothenberg, D., Wang, C., Lin, C.-Y., Chen, Y. D., and Lau, N. C.: Assessing the impacts of seasonal and vertical atmospheric conditions on air quality over the Pearl River Delta region, Atmos. Environ., 180, 69–78, https://doi.org/10.1016/j.atmosenv.2018.02.039, 2018a.
Tong, C. H. M., Yim, S. H. L., Rothenberg, D., Wang, C., Lin, C.-Y., Chen, Y. D., and Lau, N. C.: Projecting the impacts of atmospheric conditions under climate change on air quality over the Pearl River Delta region, Atmos. Environ., 193, 79–87, https://doi.org/10.1016/j.atmosenv.2018.08.053, 2018b.
Unal, Y. S., Tan, E., and Mentes, S. S.: Summer heat waves over western Turkey between 1965 and 2006, Theor. Appl. Climatol., 112, 339–350, https://doi.org/10.1007/s00704-012-0704-0, 2013.
Wang, M. Y., Yim, S. H. L., Wong, D. C., and Ho, K. F.: Source contributions of surface ozone in China using an adjoint sensitivity analysis, Sci. Total Environ., 662, 385–392, https://doi.org/10.1016/j.scitotenv.2019.01.116, 2019.
Wang, M. Y., Yim, S. H. L., Dong, G. H., Ho, K. F., and Wong, D. C.: Mapping ozone source-receptor relationship and apportioning the health impact in the Pearl River Delta region using adjoint sensitivity analysis, Atmos. Environ., 222, 117026, https://doi.org/10.1016/j.atmosenv.2019.117026, 2020.
Wang, Y., Yim, S. H. L., Yang, Y., and Morin, C. W.: The effect of urbanization and climate change on the mosquito population in the Pearl River Delta region of China, Int. J. Biometeorol., 64, 501–512, https://doi.org/10.1007/s00484-019-01837-4, 2020.
Xia, Y., Guan, D., Meng, J., Li, Y., and Shan, Y.: Assessment of the pollution–health–economics nexus in China, Atmos. Chem. Phys., 18, 14433–14443, https://doi.org/10.5194/acp-18-14433-2018, 2018.
Xie, M., Zhu, K., Wang, T., Feng, W., Gao, D., Li, M., Li, S., Zhuang, B., Han, Y., Chen, P., and Liao, J.: Changes in regional meteorology induced by anthropogenic heat and their impacts on air quality in South China, Atmos. Chem. Phys., 16, 15011–15031, https://doi.org/10.5194/acp-16-15011-2016, 2016.
Yang, Y., Yim, S. H. L., Haywood, J., Osborne, M., Chan, J. C. S., Zeng, Z., and Cheng, J. C. H.: Characteristics of Heavy Particulate Matter Pollution Events Over Hong Kong and Their Relationships With Vertical Wind Profiles Using High-Time-Resolution Doppler Lidar Measurements, J. Geophys. Res.-Atmos., 124, 9609–9623, https://doi.org/10.1029/2019JD031140, 2019.
Yim, S. H. L.: Development of a 3D Real-Time Atmospheric Monitoring System (3DREAMS) Using Doppler LiDARs and Applications for Long-Term Analysis and Hot-and-Polluted Episodes, Remote Sens., 12, 1036, https://doi.org/10.3390/rs12061036, 2020.
Yim, S. H. L., Fung, J. C. H., Lau, A. K. H., and Kot, S. C.: Air ventilation impacts of the “wall effect” resulting from the alignment of high-rise buildings, Atmos. Environ., 43, 4982–4994, https://doi.org/10.1016/j.atmosenv.2009.07.002, 2009.
Yim, S. H. L., Fung, J. C. H., and Lau, A. K. H.: Use of high-resolution MM5/CALMET/CALPUFF system: SO2 apportionment to air quality in Hong Kong, Atmos. Environ., 44, 4850–4858, https://doi.org/10.1016/j.atmosenv.2010.08.037, 2010.
Yim, S. H. L., Fung, J. C. H., and Ng, E. Y. Y.: An assessment indicator for air ventilation and pollutant dispersion potential in an urban canopy with complex natural terrain and significant wind variations, Atmos. Environ., 94, 297–306, https://doi.org/10.1016/j.atmosenv.2014.05.044, 2014.
Yim, S. H. L., Lee, G. L., Lee, I. H., Allroggen, F., Ashok, A., Caiazzo, F., Eastham, S. D., Malina, R., and Barrett, S. R. H.: Global, regional and local health impacts of civil aviation emissions, Environ. Res. Lett., 10, 034001, https://doi.org/10.1088/1748-9326/10/3/034001, 2015.
Yim, S. H. L., Gu, Y., Shapiro, M. A., and Stephens, B.: Air quality and acid deposition impacts of local emissions and transboundary air pollution in Japan and South Korea, Atmos. Chem. Phys., 19, 13309–13323, https://doi.org/10.5194/acp-19-13309-2019, 2019a.
Yim, S. H. L., Hou, X., Guo, J., and Yang, Y.: Contribution of local emissions and transboundary air pollution to air quality in Hong Kong during El Niño-Southern Oscillation and heatwaves, Atmos. Res., 218, 50–58, https://doi.org/10.1016/j.atmosres.2018.10.021, 2019b.
Yim, S. H. L., Wang, M., Gu, Y., Yang, Y., Dong, G., and Li, Q.: Effect of Urbanization on Ozone and Resultant Health Effects in the Pearl River Delta Region of China, J. Geophys. Res.-Atmos., 124, 11568–11579, https://doi.org/10.1029/2019JD030562, 2019c.
Yu, M., Carmichael, G. R., Zhu, T., and Cheng, Y.: Sensitivity of predicted pollutant levels to anthropogenic heat emissions in Beijing, Atmos. Environ., 89, 169–178, https://doi.org/10.1016/j.atmosenv.2014.01.034, 2014.
Zhang, H., Wang, Y., Park, T.-W., and Deng, Y.: Quantifying the relationship between extreme air pollution events and extreme weather events, Atmos. Res., 188, 64–79, https://doi.org/10.1016/j.atmosres.2016.11.010, 2017.
Zhang, Q., Streets, D. G., Carmichael, G. R., He, K. B., Huo, H., Kannari, A., Klimont, Z., Park, I. S., Reddy, S., Fu, J. S., Chen, D., Duan, L., Lei, Y., Wang, L. T., and Yao, Z. L.: Asian emissions in 2006 for the NASA INTEX-B mission, Atmos. Chem. Phys., 9, 5131–5153, https://doi.org/10.5194/acp-9-5131-2009, 2009.
Zheng, J., Zhang, L., Che, W., Zheng, Z., and Yin, S.: A highly resolved temporal and spatial air pollutant emission inventory for the Pearl River Delta region, China and its uncertainty assessment, Atmos. Environ., 43, 5112–5122, https://doi.org/10.1016/j.atmosenv.2009.04.060, 2009.
This study analyzed the nature, mechanisms and drivers for hot-and-polluted episodes (HPEs) in the Pearl River Delta, China. A total of eight HPEs were identified and can be grouped into three clusters of HPEs that were respectively driven (1) by weak subsidence and convection induced by approaching tropical cyclones, (2) by calm conditions with low wind speed in the lower atmosphere and (3) by the combination of both aforementioned conditions.
This study analyzed the nature, mechanisms and drivers for hot-and-polluted episodes (HPEs) in...