Chīrāla, nestled in the Prakasam district of Andhra Pradesh, India, occupies a geographically significant position within the Eastern Ghats. Located at coordinates 15.8246°N, 80.3521°E, the city benefits from a relatively low elevation, contributing to a warmer climate. The surrounding landscape is characterised by undulating hills and fertile plains, typical of the region’s transition zone between the coastal Andhra plains and the hillier interior. Chīrāla’s proximity to the Bay of Bengal, approximately 60km east, introduces a maritime influence, moderating temperatures but also potentially contributing to humidity and localised fog formation. The urban-rural gradient is pronounced; the city centre is densely populated, with a gradual transition to agricultural lands dominated by rice paddies and horticultural crops as one moves outwards. While not a major industrial hub, the presence of small-scale brick kilns and agricultural processing units in the surrounding areas contributes to particulate matter emissions. The terrain funnels winds from the west during the monsoon, and the relatively sheltered location can sometimes lead to stagnant air conditions, exacerbating pollution build-up. Understanding this interplay of geography and activity is crucial for assessing and mitigating air quality challenges in Chīrāla.

Chīrāla experiences a tropical climate, with distinct wet and dry seasons heavily influencing air quality. The post-monsoon period (October-November) often sees a temporary improvement as rainfall washes away pollutants, but this is short-lived. The dry season (December-May) is typically the most challenging, with lower humidity and increased dust from agricultural activities and unpaved roads. January and February are particularly prone to stagnant air, leading to pollutant concentration. The summer months (March-May) bring high temperatures and increased photochemical smog formation, impacting ozone levels. The southwest monsoon (June-September) offers significant relief, with heavy rainfall effectively cleansing the atmosphere. However, increased humidity can also promote the formation of secondary pollutants. Sensitive groups – children, the elderly, and those with respiratory conditions – should limit outdoor activity during the dry season, particularly in January-May. During the monsoon, while air is cleaner, the risk of waterborne diseases increases, requiring caution. Monitoring wind patterns is vital; westerly winds during the monsoon can transport pollutants from inland sources, while easterly breezes can bring in maritime influences. Avoiding peak traffic hours is always advisable.