Air quality in Delhi during the 2022 Diwali festival: evaluation of low-cost community sensors compared to ground-based government and satellite observations

Particulate matter is an important aspect of air quality monitoring as it directly affects human health. Commonly, spectrometers from satellites are used for broad coverage of aerosol levels which indicate levels of particulate matter. It is crucial to determine accurate methods for measurement, especially in urban areas. However, local variations in poor air quality may not be appropriately captured by local government monitoring to inform modeling. Low-cost sensing has led to advancements in understanding local levels of pollution in urban areas. By investigating the variance of remote sensing and ground-based low-cost and government sensors, we assess data quality. We evaluate variance to calculate the agreement of measurements and trends and determine if the values are within acceptable ranges compared to standard ground-based government sensors. We expect the four data sources will be similar in how they change over time, nonetheless, disagreement could be a function of various factors affecting how the data is measured. Advancement in understanding variation in low-cost air quality sensors enables more effective reuse of data for modeling and health applications.