Fog characteristics study over the IGI Airport, New Delhi during the winter seasons 2010-2022

Indira Gandhi International (IGI) Airport, New Delhi is one of the busiest Airport in the world is being affected by severe fog in every winter season which results significant disruption to the aviation activities. In this view, a fog characteristics study has been performed during the winter seasons from 2010 to 2022 using the available Meteorological Aerodrome Report (METAR) data at IGI Airport. To better understand the trend in fog characteristics, a detailed analysis on monthly fog frequency, inter winter season comparison, fog duration and inter annual variability based on both fog days and duration have also been carried out. An increasing trend in fog frequency and duration for all categories of fog has been observed from November to January followed by a decrease in February. However, the fog frequency and duration of moderate, dense and very dense fog have been observed to be still higher in February in comparison to November. Further, an increasing trend in fog frequency during 2010-17 season followed by a significant reduction in 2017-22 has also been identified. Moreover, the trend in duration of shallow and moderate fog remains similar during the entire period of study whereas the dense and very dense fog have shown the similar characteristics during 2010-22 except in 2014-15 and 2015-16 seasons. Finally, all these better understanding on the fog characteristics can lead to substantial improvements on various fog now-casting/forecasting activities.