Urbanisation-driven shifts in fog patterns and fog hole formation in the Indo-Gangetic Plain

Recent studies indicate a global decline in fog occurrences, particularly in urban areas. This study investigates fog trends across the Indo-Gangetic Plain, focusing on the impact of urbanisation using long-term ground and satellite data. Despite a general increase in fog frequencies elsewhere, we find a notable decline in dense fog occurrences in the megacity Delhi. Satellite data reveal that expanding fog holes over major urban areas strongly correlate with the underlying urban and built-up areas. These findings highlight the substantial role of urban expansion in altering fog patterns, with broad implications for aviation and other sectors reliant on accurate fog prediction.