Empirical Investigation of Fog Climatology and Its Impacts on Aviation at Murtala Muhammed International Airport, Lagos

Fog at major international airports creates significant safety risks, flight delays, and economic costs, yet the climatology of fog at Lagos's Murtala Muhammed International Airport and its operational aviation impacts have not been rigorously studied. This study empirically investigates fog climatology at Murtala Muhammed Airport and quantifies its impact on flight operations using hourly visibility observations from the NiMet aeronautical meteorological station for the period 2014 to 2023. Fog events were classified by onset mechanism, intensity category, and persistence duration using synoptic analysis and boundary layer stability indices computed from radiosonde data. Flight delay and cancellation data from the Nigerian Civil Aviation Authority were cross-referenced with fog event records. Results document an annual average of 41 fog events at the airport, with 89 percent occurring during the October to January period and peak frequency between 02:00 and 07:00 local time. Advection fog associated with the onshore flow of moist marine air from the Gulf of Guinea is identified as the predominant fog type, accounting for 71 percent of all events. Fog events reduce visibility below the CAT I instrument landing system minimum of 800 metres on an average of 23 occasions per year, generating measurable cascading disruption to aircraft scheduling. Econometric analysis estimates an annual economic cost of fog-related delays at approximately 4.8 billion naira. Recommendations include CAT II approach procedure certification and improved nowcasting of fog dissipation timing. Keywords: fog, airport, Murtala Muhammed, aviation, visibility climatology.