Article
Environmental Sciences
Muhammad Bilal, Alaa Mhawish, Md. Arfan Ali, Janet E. Nichol, Gerrit de Leeuw, Khaled Mohamed Khedher, Usman Mazhar, Zhongfeng Qiu, Max P. Bleiweiss, Majid Nazeer
Summary: The SEMARA approach, which combines the SREM and SARA methods, was used to retrieve AOD from satellite data over bright urban surfaces in Beijing. The approach showed high accuracy and small errors in the AOD retrievals, making it suitable for aerosol monitoring in urban areas.
Article
Environmental Sciences
Mijeong Kim, Kyunghwa Lee, Myungje Choi
Summary: The regional and global scale of aerosols in the atmosphere can be quantified using the aerosol optical depth (AOD) retrieved from satellite observations. To obtain reliable satellite AODs, conducting consistent validations and refining retrieval algorithms are crucial. This study examined the impact of the wavelength and spatial collocation radius variations by comparing AODs at 550 nm derived from the geostationary ocean color imager (GOCI) with those obtained from the AERONET for the year 2016. The variability was higher in the validation results when the spatial collocation radius was longer and the AODs were higher, compared to the selection of the wavelength.
Article
Environmental Sciences
Ming Zhang, Lei Zhang, Qingqing He, Yanbin Yuan
Summary: The study evaluated the performance of the MODIS C6.1 3 km AOD product over China, finding that the C6.1_3km product outperformed the C6_3km product in urban areas and showed similar performance to the C6.1_10km product. However, there still exists an overestimation of AOD values over urban areas in the C6.1_3km aerosol product, and refinement of the DT algorithm is needed for further improvement.
ATMOSPHERIC ENVIRONMENT
(2022)
Article
Environmental Sciences
Ping Wang, Qingxin Tang, Yuxin Zhu, Ke Zheng, Tianquan Liang, Quanzhou Yu, Yaqian He
Summary: This study verified the accuracy and applicability of the MAIAC AOD 1 km products in East Asia using AERONET AOD data. The results showed that MAIAC AOD had overall high accuracy in East Asia, but there were differences in performance among different regions and climate zones.
Article
Environmental Sciences
Yu Wang, Md Arfan Ali, Muhammad Bilal, Zhongfeng Qiu, Song Ke, Mansour Almazroui, Md Monirul Islam, Yuanzhi Zhang
Summary: This study analyzed aerosol optical depth (AOD) data in 13 cities of Jiangsu Province, finding higher AOD in summer and lower in winter, with relatively common frequencies of 0.3 <= AOD < 0.5 associated with anthropogenic activities, increased emissions, and changes in meteorological circumstances.
Article
Environmental Sciences
Kumari Aditi, Abhishek Singh, Tirthankar Banerjee
Summary: The retrieval accuracy and stability of two aerosol retrieval algorithms, Deep Blue (DB) and Dark Target (DT), applied on VIIRS on-board S-NPP satellite over South Asia, were evaluated. The results showed that DB efficiently retrieved fine aerosol features over bright arid surfaces and smoke/dust dominating events, while DT was better at identifying small fire events under dark vegetated surfaces. However, both algorithms showed unsatisfactory retrieval accuracy against AERONET, with a low percentage of valid retrievals and high RMSE and bias. Further refinement is required for the accuracy of both algorithms to continue the MODIS AOD legacy over South Asia.
ENVIRONMENTAL POLLUTION
(2023)
Article
Environmental Sciences
Anum Liaqut, Salman Tariq, Isma Younes
Summary: In recent years, the South Asian region has faced frequent and severe smog events due to rapid population growth and increased anthropogenic activities, particularly in the Indo-Gangetic Plain (IGP). This study investigates aerosol properties over selected AERONET sites in the IGP during the smog period. Different aerosol types were categorized, and HYSPLIT cluster analysis was used to trace the transmission paths and potential sources of aerosols.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2023)
Article
Environmental Sciences
Somaya Falah, Alaa Mhawish, Meytar Sorek-Hamer, Alexei I. Lyapustin, Itai Kloog, Tirthankar Banerjee, Fadi Kizel, David M. Broday
Summary: This study highlights the importance of spatial and temporal averaging in AOD retrievals, as well as the significant impact of different environmental attributes on the accuracy of MAIAC AOD retrievals. Vegetated areas showed better performance in AOD retrievals compared to arid areas, indicating the sensitivity of retrieval accuracy to environmental factors.
ATMOSPHERIC ENVIRONMENT
(2021)
Article
Environmental Sciences
Gopika Gupta, M. Venkat Ratnam, B. L. Madhavan, C. S. Narayanamurthy
Summary: This study uses a multivariate regression trend model to investigate global AOD trends and draws conclusions about satellite measurements and ground observations. Emission control policies, reduction in forest fires, and calm surface winds are the main reasons for the decrease in AOD, while there is an increase in AOD trends in the South Africa region.
ATMOSPHERIC ENVIRONMENT
(2022)
Article
Meteorology & Atmospheric Sciences
Sujin Eom, Jhoon Kim, Seoyoung Lee, Brent N. Holben, Thomas F. Eck, Sung -Bin Park, Sang Seo Park
Summary: In this study, we analyzed the trends of aerosol types in Korea, China, and Japan using data from Aerosol Robotic Network (AERONET), Visible Infrared Imaging Radiometer Suite (VIIRS), and Ozone Monitoring Instrument (OMI). Our results showed decreasing trends in aerosol optical depth (AOD), angstrom exponent (AE), and fine mode fraction (FMF) in all countries, which can be attributed to the reduction of anthropogenic emissions. The proportions of carbonaceous aerosols (CA) and non-absorbing aerosols (NA) also decreased based on both ground and satellite data. Changes in aerosol types and properties were observed in both ground and satellite data, indicating a steady decrease in fine aerosol pollution in East Asia.
ATMOSPHERIC RESEARCH
(2022)
Article
Environmental Sciences
Horatiu Ioan Stefanie, Andrei Radovici, Alexandru Mereuta, Viorel Arghius, Horia Camarasan, Dan Costin, Camelia Botezan, Camelia Ginsca, Nicolae Ajtai
Summary: This study investigates the aerosol climatology in the Cluj-Napoca area in Romania using 10 years of ground-based measurements from 2010 to 2020. The results show higher aerosol loads in July and August, and the angstrom exponent has the lowest values in April and May, and the highest in August. The study also performs aerosol classification using AERONET data.
Review
Environmental Sciences
Mikalai Filonchyk, Michael Peterson, Haowen Yan, Shuwen Yang, Anatoli Chaikovsky
Summary: This study investigates the columnar optical, microphysical and radiative properties of aerosols measured at the AERONET station in Minsk, Belarus. The results show a noticeable decrease in aerosol optical depth and increase in Angstrom exponent over the study period, with higher aerosol concentrations observed in spring and summer compared to winter.
ATMOSPHERIC ENVIRONMENT
(2021)
Article
Environmental Sciences
Manish Soni, Amit Singh Chandel, Sunita Verma, Swagata Payra, Divya Prakash, Brent Holben
Summary: This study investigates the aerosol climatology over four AERONET sites on different continents, revealing high aerosol concentration and dominance of dust aerosols in locations like Jaipur and Ilorin, while sites in America and Australia are relatively pristine. The radiative forcing and efficiency also vary significantly between Africa-Asia and America-Australia sites.
ATMOSPHERIC ENVIRONMENT
(2021)
Article
Environmental Sciences
Akhilesh Kumar, Manu Mehta
Summary: This study explores the applicability of a simple iterative approach for retrieving aerosol optical depth (AOD) over diverse land surface types. The results show a strong correspondence between retrieved AOD and actual measurements, indicating that the iterative approach can be adopted for most sensors.
ATMOSPHERIC ENVIRONMENT
(2023)
Article
Environmental Sciences
Pei Zhou, Yang Wang, Jane Liu, Linglin Xu, Xiang Chen, Likun Zhang
Summary: This study investigated the difference between global and regional aerosol models and their impact on satellite AOD retrieval. It found that aerosols can be classified into five types with different optical and physical parameters. The regional aerosol model performed better than the global model in simulating air pollution events and AOD.
ATMOSPHERIC ENVIRONMENT
(2023)
Article
Environmental Sciences
Paria Ettehadi Osgouei, Gareth Roberts, Sinasi Kaya, Muhammad Bilal, Jadunandan Dash, Elif Sertel
Summary: Aerosol loading has significant impacts on radiative forcing, climate, and human health. This study evaluated and compared multiple satellite aerosol products in the Eastern Mediterranean and the Black Sea region, with VIIRS aerosol product showing the best performance over coastal areas.
ATMOSPHERIC ENVIRONMENT
(2022)
Article
Environmental Sciences
Alaa Mhawish, Chandan Sarangi, Priyadharshini Babu, Manish Kumar, Muhammad Bilal, Zhongfeng Qiu
Summary: Post monsoonal agricultural Crop Residue Burning (CRB) in northwestern India significantly affects the air quality in Delhi. The study shows that the disproportionate increase in PM2.5 in Delhi compared to the source region can be explained by the semi-direct effect of aerosol-boundary layer interactions. Control of local anthropogenic emissions can help alleviate the extreme haze episodes in Delhi.
REMOTE SENSING OF ENVIRONMENT
(2022)
Review
Environmental Sciences
Muhammad Azher Hassan, Tariq Mehmood, Ehtisham Lodhi, Muhammad Bilal, Afzal Ahmed Dar, Junjie Liu
Summary: Air is a diverse mixture of gaseous and suspended solid particles. It is polluted by various substances daily, causing health effects on humans. Particulate matter (PM) pollution is a major concern and has been linked to the spread of COVID-19. This review provides an overview of recent developments in COVID-19 research related to ambient particulate studies, including the impact of lockdown measures on particulate pollution, transmission mechanisms of COVID-19, and the combined health effects of PM pollution.
INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH
(2022)
Article
Environmental Sciences
Zeeshan Javed, Muhammad Bilal, Zhongfeng Qiu, Guanlin Li, Osama Sandhu, Khalid Mehmood, Yu Wang, Md. Arfan Ali, Cheng Liu, Yuhang Wang, Ruibin Xue, Daolin Du, Xiaojun Zheng
Summary: This study investigated the spatiotemporal variation of trace gases and particulate matter over cities in the Yangtze River Delta region, as well as the characteristics of different pollution episodes. The impact of the China clean air action plan, trans-boundary pollution, and meteorological conditions were examined. The results showed reductions in primary pollutants concentrations, but the formation of secondary pollutants remains a concern. The study highlights the need for continuous monitoring and city-specific policies to effectively deal with metropolitan pollution.
ENVIRONMENTAL SCIENCES EUROPE
(2022)
Letter
Engineering, Environmental
Muhammad Bilal, Gerrit de Leeuw, Janet E. Nichol, Max P. Bleiweiss, Alaa Mhawish, Leiku Yang, Huabin Chai, Md. Arfan Ali
JOURNAL OF HAZARDOUS MATERIALS
(2023)
Article
Environmental Sciences
Mozhgan Bagherinia, Siamak Bodaghpour, Neamat Karimi, Fatemeh Ghasempour, Muhammad Bilal, Alaa Mhawish
Summary: Based on ground-based and satellite-based data, spatio-temporal analyses of air quality in Tehran during the lockdown periods in 2020 and 2021 were conducted. The study evaluated the differences in emissions of six air pollutants at different time scales. The results showed a decrease in pollution levels in 2020 compared to the baseline period, but a smaller reduction in 2021 and an increase in PM2.5 and PM10 levels. Satellite-based concentrations varied compared to the pre-lockdown year, with consistent trends in AOD during dust events in March and April.
GEOCARTO INTERNATIONAL
(2023)
Article
Environmental Sciences
Miao Zhang, Shiyong Chen, Xingang Zhang, Si Guo, Yunuo Wang, Feifei Zhao, Jinhan Chen, Pengcheng Qi, Fengxian Lu, Mingchun Chen, Muhammad Bilal
Summary: The purpose of this study is to investigate the air quality levels of Nanyang city according to Chinese air quality standards. The study analyzed the concentrations of fine particulate matter (PM2.5), coarse particulate matter (PM10), and total suspended particulate (TSP) from 19 November 2021 to 19 March 2022 in Nanyang city. The results showed that the air quality in Nanyang city remains polluted in winter, with higher concentrations of PM2.5 compared to PM10 and TSP. Vehicular emissions were identified as a major cause of air pollution in the city, and there was a positive correlation between particulate matter and relative humidity.
Article
Remote Sensing
Majid Nazeer, Mohammad M. M. Alsahli, Janet Elizabeth Nichol, Jiayi Pan, Weicheng Wu, Muhammad Bilal, Urooj Saeed
Summary: The overgrowth of algae in aquatic ecosystems is a serious threat, and it has been increasing due to human activities. To protect and sustain these ecosystems, it is crucial to understand how the aquatic environment promotes algae growth through comprehensive monitoring. We propose a novel Three band Macroalgae Index (TMI) using Landsat-8 Operational Land Imager (OLI) to detect and monitor algae overgrowth in aquatic ecosystems.
INTERNATIONAL JOURNAL OF REMOTE SENSING
(2023)
Article
Forestry
Sawaid Abbas, Janet E. Nichol, Syed Muhammad Irteza, Muhammad Usman
Summary: In Hong Kong, grasslands are maintained by fire on disturbed and abandoned land and native forests are regenerating in many areas alongside frequent burning. Understanding the major determinants of secondary succession is important for forest management policies, as forests are important for biodiversity conservation, watershed protection, and carbon cycling. This study examines the relationship between burning regimes and forest succession using satellite images, aerial photographs, and field plot data. The results show that moderate burning allows the regeneration of native forests, and once the shrub stage is reached, succession to closed forest is relatively rapid.
Article
Environmental Sciences
Miao Zhang, Si Guo, Yunuo Wang, Shiyong Chen, Jinhan Chen, Mingchun Chen, Muhammad Bilal
Summary: A ground-based dual-wavelength lidar system was used to investigate the vertical distribution of aerosol optical characteristics in Nanyang City. The results showed higher aerosol loadings and variations at different altitudes on polluted days compared to non-polluted days. The study also found that aerosol optical depth values were ten times larger on polluted days than non-polluted days.
Article
Computer Science, Information Systems
Muhammad Usman, Mahnoor Ejaz, Janet E. Nichol, Muhammad Shahid Farid, Sawaid Abbas, Muhammad Hassan Khan
Summary: Farmland trees play a crucial role in the local economy, providing farmers with various resources such as fuelwood, food, fodder, medicines, and building materials. Mapping tree species is essential for ecological, socio-economic, and natural resource management purposes. This study examines the use of high-resolution remotely sensed imagery for tree species classification in the agricultural landscape of Northern Nigeria.
ISPRS INTERNATIONAL JOURNAL OF GEO-INFORMATION
(2023)
Article
Ecology
Umesh Chandra Dumka, Panagiotis G. Kosmopoulos, Effrosyni Baxevanaki, Dimitris G. Kaskaoutis, Muhammad Nurul Huda, Md Firoz Khan, Muhammad Bilal, Balram Ambade, Sujan Khanal, Pavel Munshi
Summary: This study estimates the radiative forcing by biomass burning and dust aerosols over the Indian subcontinent, highlighting the importance of growing biomass burning for climate change and air quality in the region.
Article
Geochemistry & Geophysics
Farhan Mustafa, Lingbing Bu, Qin Wang, Muhammad Shahzaman, Muhammad Bilal, Rana Waqar Aslam, Changzhe Dong
Summary: This study extracted near-surface CO2 concentration data from satellite and model datasets to investigate the spatiotemporal distribution of CO2 and its influencing factors in five regions of Asia. The results showed that anthropogenic CO2 emissions and winds primarily controlled the spatial distribution of near-surface CO2 in Asia, while the terrestrial ecosystem and winds played a role in areas with lower anthropogenic emissions. The temporal distribution of near-surface CO2 was found to be inversely related to vegetation, precipitation, and relative humidity in monsoon-influenced regions, but positively related in arid and semiarid regions. The findings were supported by the correlations among these variables.
IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING
(2022)
Article
Environmental Sciences
Muhammad Bilal, Alaa Mhawish, Md. Arfan Ali, Janet E. Nichol, Gerrit de Leeuw, Khaled Mohamed Khedher, Usman Mazhar, Zhongfeng Qiu, Max P. Bleiweiss, Majid Nazeer
Summary: The SEMARA approach, which combines the SREM and SARA methods, was used to retrieve AOD from satellite data over bright urban surfaces in Beijing. The approach showed high accuracy and small errors in the AOD retrievals, making it suitable for aerosol monitoring in urban areas.