Lagatar24 Desk
New Delhi: Each winter, the Indo-Gangetic Plain becomes enveloped in a thick layer of fog, disrupting transportation and posing health risks. On Friday, Delhi and its surrounding areas experienced one of the densest fogs of the season, with satellite imagery showing the entire plain covered. This recurring phenomenon, observed annually in December and January, is caused by a combination of meteorological conditions and human activities.
Key Factors Behind North India’s Dense Fog
1.Temperature Inversion
During winter, longer nights cause the ground to cool rapidly. This leads to temperature inversion, where colder air near the surface is trapped beneath warmer air. Moisture and pollutants accumulate, resulting in dense fog.
2.High Humidity
The Himalayas and major rivers like the Ganga, Yamuna, Indus, and Brahmaputra contribute high moisture levels to the region. As temperatures drop, relative humidity rises, triggering fog formation.
3.Western Disturbances
Periodic western disturbances, moisture-laden weather systems from the Mediterranean, bring cool air and sometimes rain. These disturbances increase atmospheric moisture, intensifying fog.
4.Stagnant Winds
The region often experiences calm or light winds, frequently below 4 km/h. These stagnant air masses prevent fog dispersal, allowing it to linger for extended periods.
5.Air Pollution
Pollution from vehicles, industries, and stubble burning in Punjab and Haryana adds to the problem. Pollutants act as condensation nuclei, increasing fog density and creating smog, a hazardous mix of smoke and fog.
6.Topography
The flat terrain of the Indo-Gangetic Plain, bordered by the Himalayan range, traps moisture and pollutants. This unique geography limits air circulation, exacerbating fog formation.
Impacts of Fog
The dense fog significantly affects transportation, disrupting flights, train schedules, and road traffic. It also exacerbates respiratory issues due to its interaction with pollutants. The economic costs of delays and accidents add to the burden of this seasonal phenomenon.
Steps to Mitigate Fog’s Impact
Understanding the underlying factors of winter fog can help reduce its effects. Potential measures include:
•Reducing pollution by curbing vehicular emissions and controlling stubble burning.
•Improved urban planning to mitigate the urban heat island effect.
•Enhanced weather forecasting systems to provide timely warnings and reduce transportation disruptions.
