Identification of Sources Causing Air Pollution in Indian Cities Using Hierarchical Agglomerative Cluster Analysis

Abstract

The distressing levels of air pollution in India is becoming health hazard to the inhabitants. It's important to note that due to the nation's continued urbanisation and its heavy reliance on coal for electricity generation, air pollution is expected to get worse in some areas of India over the next few decades. Present study aims to address the issue by identifying the sources causing air pollution using Hierarchical Agglomerative Cluster Analysis [HACA]. Two years daily data (2018 and 2019), downloaded from publicly available source Kaggle.com of sixteen selected air pollution monitoring stations was used for the study. The stations were selected based upon diversified environmental conditions and local sources. HACA was successful in grouping the monitoring stations into four clusters based on their average Air Quality Index (AQI) level. These four clusters are named as Low Pollution, Moderate Pollution, High Pollution and Very High Pollution Region [LPR, MPR, HPR and VHPR] with average AQI 96; 135; 173 and 227 respectively. Discriminant Analysis (DA) confirmed the resulting clusters with 100% accuracy. It was found that stations with similar environmental factors, regional sources, and pollution amounts were clustered together. Despite numerous actions taken by the authorities to reduce air pollution, it was noticed that topographical conditions play an essential role in the rise of pollution. This study helps to implement different strategies by the authorities’ concern based on local sources and topographical conditions.