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arXiv · 2010.12373

Identification and Quantification of Aerosol Hot-spots over Lahore Region using MODIS Data

Abstract

The increased concentration of aerosols in the air caused by ever-rising urbanization and the development of various industries has horrendous consequences on human health, environment and climate. The first step to counter adverse effects of air pollution in any region is to identify locations with a high concentration of aerosols, termed aerosol hot-spots. We specifically focus on the region of Lahore, Pakistan, a city that has consistently been ranked among the top ten most polluted cities in the world. In order to identify aerosol hot-spots in the city, we utilize two-year (2017-18) Aerosol Optical Thickness (AOT) data from MODerate resolution Imaging Spectroradiometer (MODIS) on the Aqua satellite. We propose a method based on the Glowworm Swarm Optimization (GSO) algorithm that discovers several aerosol hot-spots over Lahore comprising of major highways and industrial areas. Furthermore, we formulate two quantification metrics to gauge the amount of aerosol content over each hot-spot. We also analyze the temporal variation of aerosol content that suggests the addition or suppression of pollution sources in the hot-spots. Unlike previous studies, our work provides novel insight into the regional aerosol concentration of Lahore and calls for maintenance of air quality of the regions falling under the identified aerosol hot-spots.

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Safa~Ashraf, Zubair Khalid, Muhammad Tahir, Momin Uppal. 2020-10-23. Identification and Quantification of Aerosol Hot-spots over Lahore Region using MODIS Data. https://arxiv.org/abs/2010.12373

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