Articles | Volume 21, issue 17
https://doi.org/10.5194/acp-21-13443-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/acp-21-13443-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
10 Sep 2021
Research article |
| 10 Sep 2021
| 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
Department of Geography and Resource Management, Chinese
University of Hong Kong, Sha Tin, N.T., Hong Kong, China
Chi-Yung Tam
Earth System Science Programme, Chinese University of Hong Kong,
Sha Tin, N.T., Hong Kong, China
Jianping Guo
State Key Laboratory of Severe Weather, Chinese Academy of
Meteorological Sciences, Beijing 100081, China
Department of Geography and Resource Management, Chinese
University of Hong Kong, Sha Tin, N.T., Hong Kong, China
Stanley Ho Big Data Decision Analytics Research Centre, Chinese
University of Hong Kong, Sha Tin, N.T., Hong Kong, China
Asian School of the Environment, Nanyang Technological University, 50 Nanyang Avenue, 639798 Singapore
Related authors
No articles found.
Hui Xu, Jianping Guo, Jianbo Deng, Rongfang Yang, Deli Meng, Zhen Zhang, Ning Li, Yuping Sun, Shuairu Jiang, Tianmeng Chen, Juan Chen, Liping Zeng, Yongshui Zhou, and Bing Tong
EGUsphere, https://doi.org/10.5194/egusphere-2026-1091, https://doi.org/10.5194/egusphere-2026-1091, 2026
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
Short summary
Short summary
Using a new national network of 80 cloud radars, we mapped how clouds are layered and how high they reach across China. Clouds vary strongly by region, season, and time of day, with deeper clouds in humid, unstable conditions and shallower clouds in stable or windy conditions. Also, land cover matters: forests tend to have lower cloud bases than barren land. These findings help improve weather and climate predictions.
Ning Li, Jianping Guo, Xiaoran Guo, Tianmeng Chen, Zhen Zhang, Na Tang, Yifei Wang, Honglong Yang, Yongguang Zheng, and Yongshui Zhou
Atmos. Chem. Phys., 26, 3339–3356, https://doi.org/10.5194/acp-26-3339-2026, https://doi.org/10.5194/acp-26-3339-2026, 2026
Short summary
Short summary
Nighttime rainfall often links to low-level jets (LLJs), but we lack clarity on nationwide LLJ features. We here used a nationwide radar wind profiler network to study LLJ changes 2 hours before rainfall, covering China’s 2023–2024 rainy seasons. 56% nighttime rainfall had LLJs. The LLJs-associated heavy rain needed a rapid adjustment of LLJs’ vertical structure, especially a significant intensification within 30 minutes preceding rain. This shows the importance of LLJ in nowcasting rainfall.
Xiaoran Guo, Jianping Guo, Ning Li, Zhen Zhang, Tianmeng Chen, Yu Shi, Pengzhan Yao, Shuairu Jiang, Lei Zhao, and Fei Hu
Atmos. Chem. Phys., 26, 2391–2409, https://doi.org/10.5194/acp-26-2391-2026, https://doi.org/10.5194/acp-26-2391-2026, 2026
Short summary
Short summary
Wind gusts threaten safety and infrastructure but are hard to predict. To address this gap, we studied an extreme wind gust event in Beijing on 30 May 2024. We used seven radar wind profilers to track how this gust developed. It formed when cold northeasterly air clashed with warm southerly winds as the storm moved downhill. Evaporation of rain cooled the air, boosting downward air movement and wind strength. The turbulence transferring energy from small to large eddies intensify winds.
Qi Zhang, Tianmeng Chen, Jianping Guo, Yu Wu, Bin Deng, and Junjie Yan
Geosci. Model Dev., 19, 505–522, https://doi.org/10.5194/gmd-19-505-2026, https://doi.org/10.5194/gmd-19-505-2026, 2026
Short summary
Short summary
We propose TCKF1D-Var, a thermodynamic-constrained variational framework for ground-based microwave radiometer retrievals. Using virtual potential temperature, a ratio-based cost function, and a microphysics closure, it reduces biases relative to ERA5 and 1D-Var, improves cloud liquid water representation, and enhances heavy rainfall precursors, extending lead times. This approach strengthens continuous profiling and supports high-impact weather nowcasting.
Yonglin Fang, Hancheng Hu, Xiangdong Zheng, Jianping Guo, Xingbing Zhao, Fang Ma, and Hao Wu
EGUsphere, https://doi.org/10.5194/egusphere-2025-4751, https://doi.org/10.5194/egusphere-2025-4751, 2025
Short summary
Short summary
This study shows how temperature inversions (warm air above cold) trap pollution in China. Using six years of national data, we find these "lids" frequently cause severe haze, especially in winter, by increasing pollution probability and intensity. Impacts differ by region and inversion type/strength. These findings help improve air quality forecasts and regional pollution control strategies.
Deli Meng, Jianping Guo, Juan Chen, Xiaoran Guo, Ning Li, Yuping Sun, Zhen Zhang, Na Tang, Hui Xu, Tianmeng Chen, Rongfang Yang, and Jiajia Hua
Earth Syst. Sci. Data, 17, 4023–4037, https://doi.org/10.5194/essd-17-4023-2025, https://doi.org/10.5194/essd-17-4023-2025, 2025
Short summary
Short summary
This study provides a high-resolution dataset of low-level atmospheric turbulence across China, using radar and weather balloon observations. It reveals regional and seasonal variations in turbulence, with stronger activity in spring and summer. The dataset supports weather forecasting, aviation safety, and low-altitude flight planning, aiding China's growing low-altitude economy, and is accessible at https://doi.org/10.5281/zenodo.14959025.
Xiaoran Guo, Jianping Guo, Deli Meng, Yuping Sun, Zhen Zhang, Hui Xu, Liping Zeng, Juan Chen, Ning Li, and Tianmeng Chen
Earth Syst. Sci. Data, 17, 3541–3552, https://doi.org/10.5194/essd-17-3541-2025, https://doi.org/10.5194/essd-17-3541-2025, 2025
Short summary
Short summary
Optimal atmospheric dynamic conditions are essential for convective storms. This study generates a dataset of high-resolution divergence and vorticity profiles using the measurements of a radar wind profiler mesonet in Beijing. The negative divergence and positive vorticity are present ahead of rainfall events. This suggests that this dataset can help improve our understanding of the pre-storm environment and has the potential to be applied in weather forecasting.
Juan Zhao, Jianping Guo, and Xiaohui Zheng
Geosci. Model Dev., 18, 4075–4101, https://doi.org/10.5194/gmd-18-4075-2025, https://doi.org/10.5194/gmd-18-4075-2025, 2025
Short summary
Short summary
A series of observing system simulation experiments are conducted to assess the impact of multiple radar wind profiler (RWP) networks on convective-scale numerical weather prediction. Results from three southwest-type heavy rainfall cases in the Beijing–Tianjin–Hebei region suggest the added forecast skill of ridge and foothill networks associated with the Taihang Mountains over the existing RWP network. This research provides valuable guidance for designing optimal RWP networks in the region.
Xiaozhong Cao, Qiyun Guo, Haowen Luo, Rongkang Yang, Peng Zhang, Jianping Guo, Jincheng Wang, Die Xiao, Jianping Du, Zhongliang Sun, Shijun Liu, Sijie Chen, and Anfan Huang
EGUsphere, https://doi.org/10.5194/egusphere-2025-2012, https://doi.org/10.5194/egusphere-2025-2012, 2025
Short summary
Short summary
This study aims to introduce in-situ profiling techniques and cost-effective technology for upper-air observation—the Round-trip Drifting Sounding System (RDSS)—which reduces costs relative to intensive sounding and achieves three sounding phases: Ascent-Drift-Descent (ADD). The RDSS not only provides additional data for weather analysis and numerical prediction models but also makes substantial contributions to targeted observations.
Seoung Soo Lee, Chang Hoon Jung, Jinho Choi, Young Jun Yoon, Junshik Um, Youtong Zheng, Jianping Guo, Manguttathil G. Manoj, Sang-Keun Song, and Kyung-Ja Ha
Atmos. Chem. Phys., 25, 705–726, https://doi.org/10.5194/acp-25-705-2025, https://doi.org/10.5194/acp-25-705-2025, 2025
Short summary
Short summary
This study attempts to test a general factor that explains differences in the properties of different mixed-phase clouds using a modeling tool. Although this attempt is not to identify a factor that can perfectly explain and represent the properties of different mixed-phase clouds, we believe that this attempt acts as a valuable stepping stone towards a more complete, general way of using climate models to better predict climate change.
Zhiqi Xu, Jianping Guo, Guwei Zhang, Yuchen Ye, Haikun Zhao, and Haishan Chen
Earth Syst. Sci. Data, 16, 5753–5766, https://doi.org/10.5194/essd-16-5753-2024, https://doi.org/10.5194/essd-16-5753-2024, 2024
Short summary
Short summary
Tropical cyclones (TCs) are powerful weather systems that can cause extreme disasters. Here we generate a global long-term TC size and intensity reconstruction dataset, covering a time period from 1959 to 2022, with a 3 h temporal resolution, using machine learning models. These can be valuable for filling observational data gaps and advancing our understanding of TC climatology, thereby facilitating risk assessments and defenses against TC-related disasters.
Deli Meng, Jianping Guo, Xiaoran Guo, Yinjun Wang, Ning Li, Yuping Sun, Zhen Zhang, Na Tang, Haoran Li, Fan Zhang, Bing Tong, Hui Xu, and Tianmeng Chen
Atmos. Chem. Phys., 24, 8703–8720, https://doi.org/10.5194/acp-24-8703-2024, https://doi.org/10.5194/acp-24-8703-2024, 2024
Short summary
Short summary
The turbulence in the planetary boundary layer (PBL) over the Tibetan Plateau (TP) remains unclear. Here we elucidate the vertical profile of and temporal variation in the turbulence dissipation rate in the PBL over the TP based on a radar wind profiler (RWP) network. To the best of our knowledge, this is the first time that the turbulence profile over the whole TP has been revealed. Furthermore, the possible mechanisms of clouds acting on the PBL turbulence structure are investigated.
Xiaoran Guo, Jianping Guo, Tianmeng Chen, Ning Li, Fan Zhang, and Yuping Sun
Atmos. Chem. Phys., 24, 8067–8083, https://doi.org/10.5194/acp-24-8067-2024, https://doi.org/10.5194/acp-24-8067-2024, 2024
Short summary
Short summary
The prediction of downhill thunderstorms (DSs) remains elusive. We propose an objective method to identify DSs, based on which enhanced and dissipated DSs are discriminated. A radar wind profiler (RWP) mesonet is used to derive divergence and vertical velocity. The mid-troposphere divergence and prevailing westerlies enhance the intensity of DSs, whereas low-level divergence is observed when the DS dissipates. The findings highlight the key role that an RWP mesonet plays in the evolution of DSs.
Kaixu Bai, Ke Li, Liuqing Shao, Xinran Li, Chaoshun Liu, Zhengqiang Li, Mingliang Ma, Di Han, Yibing Sun, Zhe Zheng, Ruijie Li, Ni-Bin Chang, and Jianping Guo
Earth Syst. Sci. Data, 16, 2425–2448, https://doi.org/10.5194/essd-16-2425-2024, https://doi.org/10.5194/essd-16-2425-2024, 2024
Short summary
Short summary
A global gap-free high-resolution air pollutant dataset (LGHAP v2) was generated to provide spatially contiguous AOD and PM2.5 concentration maps with daily 1 km resolution from 2000 to 2021. This gap-free dataset has good data accuracies compared to ground-based AOD and PM2.5 concentration observations, which is a reliable database to advance aerosol-related studies and trigger multidisciplinary applications for environmental management, health risk assessment, and climate change analysis.
Boming Liu, Xin Ma, Jianping Guo, Renqiang Wen, Hui Li, Shikuan Jin, Yingying Ma, Xiaoran Guo, and Wei Gong
Atmos. Chem. Phys., 24, 4047–4063, https://doi.org/10.5194/acp-24-4047-2024, https://doi.org/10.5194/acp-24-4047-2024, 2024
Short summary
Short summary
Accurate wind profile estimation, especially for the lowest few hundred meters of the atmosphere, is of great significance for the weather, climate, and renewable energy sector. We propose a novel method that combines the power-law method with the random forest algorithm to extend wind profiles beyond the surface layer. Compared with the traditional algorithm, this method has better stability and spatial applicability and can be used to obtain the wind profiles on different land cover types.
Zhiyuan Li, Kin-Fai Ho, Harry Fung Lee, and Steve Hung Lam Yim
Atmos. Chem. Phys., 24, 649–661, https://doi.org/10.5194/acp-24-649-2024, https://doi.org/10.5194/acp-24-649-2024, 2024
Short summary
Short summary
This study developed an integrated model framework for accurate multi-air-pollutant exposure assessments in high-density and high-rise cities. Following the proposed integrated model framework, we established multi-air-pollutant exposure models for four major PM10 chemical species as well as four criteria air pollutants with R2 values ranging from 0.73 to 0.93. The proposed framework serves as an important tool for combined exposure assessment in epidemiological studies.
Jianping Guo, Jian Zhang, Jia Shao, Tianmeng Chen, Kaixu Bai, 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, 16, 1–14, https://doi.org/10.5194/essd-16-1-2024, https://doi.org/10.5194/essd-16-1-2024, 2024
Short summary
Short summary
A global continental merged high-resolution (PBLH) dataset with good accuracy compared to radiosonde is generated via machine learning algorithms, covering the period from 2011 to 2021 with 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, with 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.
Hui Xu, Jianping Guo, Bing Tong, Jinqiang Zhang, Tianmeng Chen, Xiaoran Guo, Jian Zhang, and Wenqing Chen
Atmos. Chem. Phys., 23, 15011–15038, https://doi.org/10.5194/acp-23-15011-2023, https://doi.org/10.5194/acp-23-15011-2023, 2023
Short summary
Short summary
The radiative effect of cloud remains one of the largest uncertain factors in climate change, largely due to the lack of cloud vertical structure (CVS) observations. The study presents the first near-global CVS climatology using high-vertical-resolution soundings. Single-layer cloud mainly occurs over arid regions. As the number of cloud layers increases, clouds tend to have lower bases and thinner layer thicknesses. The occurrence frequency of cloud exhibits a pronounced seasonal diurnal cycle.
Boming Liu, Xin Ma, Jianping Guo, Hui Li, Shikuan Jin, Yingying Ma, and Wei Gong
Atmos. Chem. Phys., 23, 3181–3193, https://doi.org/10.5194/acp-23-3181-2023, https://doi.org/10.5194/acp-23-3181-2023, 2023
Short summary
Short summary
Wind energy is one of the most essential clean and renewable forms of energy in today’s world. However, the traditional power law method generally estimates the hub-height wind speed by assuming a constant exponent between surface and hub-height wind speeds. This inevitably leads to significant uncertainties in estimating the wind speed profile. To minimize the uncertainties, we here use a machine learning algorithm known as random forest to estimate the wind speed at hub height.
Seoung Soo Lee, Junshik Um, Won Jun Choi, Kyung-Ja Ha, Chang Hoon Jung, Jianping Guo, and Youtong Zheng
Atmos. Chem. Phys., 23, 273–286, https://doi.org/10.5194/acp-23-273-2023, https://doi.org/10.5194/acp-23-273-2023, 2023
Short summary
Short summary
This paper elaborates on process-level mechanisms regarding how the interception of radiation by aerosols interacts with the surface heat fluxes and atmospheric instability in warm cumulus clouds. This paper elucidates how these mechanisms vary with the location or altitude of an aerosol layer. This elucidation indicates that the location of aerosol layers should be taken into account for parameterizations of aerosol–cloud interactions.
Seoung Soo Lee, Jinho Choi, Goun Kim, Kyung-Ja Ha, Kyong-Hwan Seo, Chang Hoon Jung, Junshik Um, Youtong Zheng, Jianping Guo, Sang-Keun Song, Yun Gon Lee, and Nobuyuki Utsumi
Atmos. Chem. Phys., 22, 9059–9081, https://doi.org/10.5194/acp-22-9059-2022, https://doi.org/10.5194/acp-22-9059-2022, 2022
Short summary
Short summary
This study investigates how aerosols affect clouds and precipitation and how the 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.
Peilin Song, Yongqiang Zhang, Jianping Guo, Jiancheng Shi, Tianjie Zhao, and Bing Tong
Earth Syst. Sci. Data, 14, 2613–2637, https://doi.org/10.5194/essd-14-2613-2022, https://doi.org/10.5194/essd-14-2613-2022, 2022
Short summary
Short summary
Soil moisture information is crucial for understanding the earth surface, but currently available satellite-based soil moisture datasets are imperfect either in their spatiotemporal resolutions or in ensuring 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 the potential to promote the investigation of earth hydrology and be extended to the global scale.
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, https://doi.org/10.5194/essd-14-907-2022, https://doi.org/10.5194/essd-14-907-2022, 2022
Short summary
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, https://doi.org/10.5194/acp-22-1669-2022, https://doi.org/10.5194/acp-22-1669-2022, 2022
Short summary
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., https://doi.org/10.5194/amt-2022-26, https://doi.org/10.5194/amt-2022-26, 2022
Publication in AMT not foreseen
Short summary
Short 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, https://doi.org/10.5194/acp-22-765-2022, https://doi.org/10.5194/acp-22-765-2022, 2022
Short summary
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.
Qingqing He, Mengya Wang, and Steve Hung Lam Yim
Atmos. Chem. Phys., 21, 18375–18391, https://doi.org/10.5194/acp-21-18375-2021, https://doi.org/10.5194/acp-21-18375-2021, 2021
Short summary
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, https://doi.org/10.5194/acp-21-17079-2021, https://doi.org/10.5194/acp-21-17079-2021, 2021
Short summary
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, https://doi.org/10.5194/acp-21-16843-2021, https://doi.org/10.5194/acp-21-16843-2021, 2021
Short summary
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, https://doi.org/10.5194/amt-14-6101-2021, https://doi.org/10.5194/amt-14-6101-2021, 2021
Short summary
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, https://doi.org/10.5194/acp-21-6199-2021, https://doi.org/10.5194/acp-21-6199-2021, 2021
Short summary
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, https://doi.org/10.5194/acp-21-5063-2021, https://doi.org/10.5194/acp-21-5063-2021, 2021
Short summary
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.
Cited articles
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. 
Karremann, M. K., Liberato, M. L. R., Ordóñez, P., and Pinto, J. G.:
Characterization of synoptic conditions and cyclones associated with top
ranking potential wind loss events over Iberia, Atmos. Sci. Lett., 17, 354–361,
https://doi.org/10.1002/asl.665, 2016. 
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., Nordio, F., Nairn, J., Zanobetti, A., and Schwartz, J. D.:
Accounting for adaptation and intensity in projecting heat wave-related
mortality, Environ. Res., 161, 464–471,
https://doi.org/10.1016/j.envres.2017.11.049, 2018. 
Wang, Y., Chan, A., Lau, G. N.-C., Li, Q., Yang, Y., and Yim, S. H. L.:
Effects of urbanization and global climate change on regional climate in the
Pearl River Delta and thermal comfort implications, 39, 2984–2997,
https://doi.org/10.1002/joc.5996, 2019. 
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. 
Short summary
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...
Altmetrics
Final-revised paper
Preprint