Air quality remains a critical environmental concern, with significant implications for public health and sustainability. In urban areas such as Greater Manchester, air pollution resulting from transportation, industrial activities, and heating systems continues to pose health risks, including respiratory and cardiovascular diseases. Despite various policy measures aimed at reducing air pollution, gaps still exist in understanding the temporal and seasonal dynamics influencing air quality variations. This study examines the temporal and seasonal variations in air quality in Greater Manchester from 2010 to 2020, using the Air Quality Index (AQI) as a composite indicator. It is found that air quality has generally improved, with a significant decline in AQI observed from 2011 to 2016. Seasonal analysis reveals that higher AQI values are recorded in spring and winter. The study emphasizes the need for air quality management strategies that incorporate seasonal variations to achieve sustainable improvements in urban air quality.