Ground-Based Remote Sensing of Aerosol Properties over a Coastal Megacity of Pakistan (original) (raw)
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A Study of Aerosol Properties over Lahore (Pakistan) by Using AERONET Data
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An Analysis of Atmospheric Aerosol Characteristics Using Remote Sensing Data in the Indian Region
Pure and Applied Geophysics, 2024
The aerosols present in the atmosphere are considered to be an essential element that directly affects the cloud properties, radiation budget of Earth, human health, and quality of air. Therefore, it is mandatory to investigate aerosol concentration and properties both in the local and global regions while studying global climate change. In this paper, an analysis of aerosol properties such as single scattering albedo (SSA), aerosol optical depth (AOD) at 500 nm, angstrom exponent (AE) (440-870 nm), and aerosol volume size distribution (VSD), which are retrieved from relatively long term AErosol RObotic NETwork (AERONET) at Karunya University, Kanpur, Gandhi College, Pune, and Jaipur is made for the years from 2010 to 2019. The comparisons of the parameters based on wavelength and seasons for the five places considered are provided. The result analysis shows that the indo gangetic plain (IGP) region places such as Gandhi College and Kanpur experience larger AOD values during the 10-year period considered as compared to other sites. The seasonal analysis of AE, SSA, and VSD reveals that the dominance of fine particles is available mainly in post-monsoon and winter season except Jaipur, whereas coarse particles always occurred in monsoon and premonsoon seasons at all the places except Karunya University. The comparison between the AODs retrieved from the MODIS (Moderate Resolution Imaging Spectroradiometer) satellite and AERONET is also provided. The comparison shows that 50% and 43.48% of MODIS-derived AOD match well with the AERONETderived AOD within the expected error values for Gandhi College and Kanpur, respectively.
Atmospheric Chemistry and Physics Discussions
In this study, the optical properties of aerosols in Penang, Malaysia were analyzed for four monsoonal seasons (northeast monsoon, pre-monsoon, southwest monsoon, and post-monsoon) based on data from the AErosol RObotic NETwork (AERONET) from February 2012 to November 2013. The aerosol distribution patterns in Penang for each monsoonal period were quantitatively identified according to the scattering plots of the aerosol optical depth (AOD) against the Angstrom exponent. A modified algorithm based on the prototype model of Tan et al. (2014a) was proposed to predict the AOD data. Ground-based measurements (i.e., visibility and air pollutant index) were used in the model as predictor data to retrieve the missing AOD data from AERONET because of frequent cloud formation in the equatorial region. The model coefficients were determined through multiple regression analysis using selected data set from in situ data. The predicted AOD of the model was generated based on the coefficients and...
International Letters of Natural Sciences
Air pollution in Pakistan is causing damage to health, environment and quality of life. Air pollution in Pakistan is not effectively monitored due to heavy cost involved in setting up ground stations. However, Satellite remote sensing can effectively monitor the air pollution in terms of Aerosol Optical Depth (AOD) at regional as well as global level. However, algorithms used to derive AOD from different sensors have some inherited differences which can pose challenges in monitoring regional AOD at high temporal resolution using more than one sensor. Therefore, this study focuses on comparison of four major satellite based AOD products namely Moderate Resolution Imaging SpectroRadiometer (MODIS), Multi-angle Imaging SpectroRadiometer (MISR), Ozone Monitoring Instrument multiwavelength (OMI) aerosol product and Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) with the ground based AErosol RObotic NETwork (AERONET) AOD which is only available from Lahore and...
Remote sensing of aerosol properties during intense smog events over Lahore (Pakistan)
Kuwait Journal of Science, 2021
In recent years, smog has been one of the main concerns in heavily populated urban areas like Lahore (Pakistan) and Kanpur (India). Atmospheric pollutants like aerosols play an important role in smog. In this paper, aerosol types are identified in smog episodes, based on Aerosol Robotic Network (AERONET) data, during 4-year period i.e., 2015-2018. Aerosols are classified based on fine mode fraction (FMF) and single scattering albedo (SSA). One of the main aerosol types which are abundant in every smog episode is Black Carbon (BC) aerosol while dust is present throughout the year. BC is responsible for radiation imbalance and is considered the main component in climate changes at regional and global levels. Furthermore, time series of aerosol optical depth (AOD) during smog episodes is used to identify the variability of aerosol burden in the atmosphere. Backward trajectories from the HYSPLIT model are used to trace the origin of aerosols during the days of maximum AOD.
Ground Based Remote Sensing of Aerosols Using AERONET in Indian Region
IEEE, 2020 International Conference on Wireless Communications Signal Processing and Networking (WiSPNET), 2020
Aerosols are defined as solid or liquid particles suspended in the atmosphere which directly affect the Earth’s radiation budget, cloud properties, air quality, and human health. Aerosol Optical Depth/Aerosol Optical Thickness (AOD/AOT) is a measure of aerosol loading, integrated through the atmospheric column. In this paper, a comparison of AOD obtained from AErosol RObotic NETwork (AERONET) at Jaipur, Pune, Gandhi College, and Karunya University is made for the years 2017, 2018. Finally, the daily average AOD obtained for May 2018 over New Delhi IMD, Jaipur, Pune, Gandhi College, Karunya University is compared and results are discussed. The comparative study of the AOD trend over Karachi and Gandhi College during the period of September 2006 to August 2014 is also made.
Atmospheric Chemistry and Physics
Obtaining continuous aerosol-optical-depth (AOD) measurements is a difficult task due to the cloud-cover problem. With the main motivation of overcoming this problem, an AOD-predicting model is proposed. In this study, the optical properties of aerosols in Penang, Malaysia were analyzed for four monsoonal seasons (northeast monsoon, pre-monsoon, southwest monsoon, and post-monsoon) based on data from the AErosol RObotic NETwork (AERONET) from February 2012 to November 2013. The aerosol distribution patterns in Penang for each monsoonal period were quantitatively identified according to the scattering plots of the Ångström exponent against the AOD. A new empirical algorithm was proposed to predict the AOD data. Ground-based measurements (i.e., visibility and air pollutant index) were used in the model as predictor data to retrieve the missing AOD data from AERONET due to frequent cloud formation in the equatorial region. The model coefficients were determined through multiple regress...
Journal of RS and GIS for Natural Resources, 2020
Currently, global climate change (GCC) and the urban heat island (UHI) phenomena are becoming serious problems, partly due to the artificial construction of the land surface. When sunlight reaches the land surface, some of it is absorbed and some is reflected. The state of the land surface directly affects the surface albedo, which determines the magnitude of solar radiation reflected by the land surface in the daytime. In order to better understand the spatial and temporal changes in surface albedo, this study investigated and analyzed the surface albedo from 2000 to 2016 (2000, 2008, and 2016) in the entire Chinese territory, based on the measurement database obtained from the Moderate Resolution Imaging Spectroradiometer (MODIS) instrument, aboard NASA's Terra satellite. It was shown that the Northeast China exhibited the largest decline in surface albedo and North China showed the largest rising trend of surface albedo from 2000 to 2016. The correlation between changes in surface albedo and the Normalized Difference Vegetation Index (NDVI) indicated that the change trend of surface albedo was opposite to that of NDVI. In addition, in order to better understand the distribution of surface albedo in the entire Chinese territory, the classifications of surface albedo in three years (2000, 2008, and 2016) were implemented using five classification methods in this study.
Remote Sensing
This research addresses the aerosol characteristics and variability over Cairo and the Greater Delta region over the last 20 years using an integrative multi-sensor approach of remotely sensed and PM10 ground data. The accuracy of these satellite aerosol products is also evaluated and compared through cross-validation against ground observations from the AErosol RObotic NETwork (AERONET) project measured at local stations. The results show the validity of using Multi-angle Imaging Spectroradiometer (MISR) and Moderate Resolution Imaging Spectroradiometer (MODIS) sensors on the Terra and Aqua platforms for quantitative aerosol optical depth (AOD) assessment as compared to Ozone Monitoring Instrument (OMI), Sea-viewing Wide Field-of-view Sensor (SeaWiFS), and POLarization and Directionality of the Earth’s Reflectances (POLDER). In addition, extracted MISR-based aerosol products have been proven to be quite effective in investigating the characteristics of mixed aerosols. Daily AERONET...
Atmosphere
Natural and anthropogenic aerosols over the Kingdom of Saudi Arabia (KSA) play a major role in affecting the regional radiation budget. The long-term variability of these aerosols’ physical and optical parameters, including aerosol optical depth (AOD) and Ångström exponent (α), were measured at a location near central KSA using the Solar Village (SV) AERONET (Aerosol Robotic Network) station during the period December 1999–January 2013. The AERONET measurements show an overall increase in AOD on an annual basis. This upward trend is mainly attributed to a prolonged increase in the monthly/seasonal mean AOD during March–June and during August–September. In contrast, lower AOD values were observed during November–December. This can be attributed to a low frequency of dust outbreaks and higher precipitation rates. An overall, weak declining trend in α was observed, except during the summer. The spring and summer seasons experienced a pronounced increase in the number of coarse particle...