The effect of fog has multifarious impacts on human life and the environment, encompassing air quality, transportation, the economy, ecology, and agriculture. These wide-ranging impacts require adjustments in daily routine and lifestyle at the individual level and initiatives at the government level. Individually, one has to plan travel according to the weather conditions and take measures to avoid the negative effects of fog on health. At the government level, the provision and regulation of facilities and infrastructure according to the dictates of foggy conditions is a surmountable challenge.
There is 0.001% water in the atmosphere, a critical component in determining the earth’s heat budget and driving climate phenomena. Clouds at altitude and fog close to the surface are evident manifestations of water as a component of the atmosphere. Altitude being the only difference, the fog is also called stratus cloud – just above the ground.
How is fog formed?
Understanding the formation of fog is imperative to comprehending its various effects. A combination of factors ranging from the chemical and physical properties of cloud condensation nuclei to the topography of the region and changes in the atmosphere or winter teleconnections influence the formation of fog.
Fog is a phenomenon of visible air condensation at or near ground level that forms when the air layer’s temperature drops to its dew point.

The dew point temperature is key to the concept of fog formation. It is the temperature at which air becomes 100% saturated with vapor and incapable of holding more water molecules in gaseous form. Any further addition of water molecules or air cooling will cause the water vapors to condense and form water droplets.
Does fog affect the Air Quality Index (AQI)?
If the air contains more pollutants, there are more chances of fog formation. Air pollutants act as cloud condensation nuclei, enhancing the fog probability due to favorable meteorological conditions. The most adverse manifestation of the interaction between fog and air pollutants is smog.

However, it doesn’t only affect the atmosphere in a harmful manner; it can also act as an agent for removing air pollutants from the atmosphere. It is imperative to reduce air pollutants in the atmosphere to accrue the positive effects of fog.
Effect of fog on Ecology
Fog has a significant role in maintaining the ecosystems of all strata, ranging from deserts to alpine and inland to coastal systems. It acts as a vector, medium, and connector for the ecosystem, providing it with critical water and nutrient subsidies. As a vector and medium, fog regulates, delivers, and supplies the flow of “critical limiting resources” – water, elements, and light – to the ecosystem. Droplets in the fog have a higher chemical concentration, transporting nutrients and pollutants incorporated into these droplets during fog formation.

Fog impacts the light climate of the ecosystem; total shortwave radiation tends to reduce by as much as 75% under foggy conditions.
[REFERENCE: https://www.ipcc.ch/site/assets/uploads/2018/02/ar4-wg1-chapter2-1.pdf]
In short, on the one hand, fog is valuable in extending or sustaining ecosystem processes that would otherwise have been slowed down or ceased due to water deficits or a lack of elements. On the other hand, ecosystem processes may be slowed down or impaired due to water saturation or excessive pollutants.
Effect of fog on Human Health
Fog is not harmful to the human body as it’s devoid of any chemicals or air pollutants and consists of only water droplets. It’s the amount of particulate matter that makes inhaling fog dangerous. The air quality index, especially in urban areas, has deteriorated to dangerous levels due to increased particulate matter in the atmosphere. People suffering from respiratory diseases have experienced deteriorated health during foggy conditions, especially patients with asthma. It is noteworthy that the phenomenon is not dangerous to humans. However, the effect of fog exacerbates the impacts of air pollution.
Is fog bad for your lungs? Inhaling fog exposes your lungs to cold and watery air, which can be damaging and may cause coughing, irritation, or chills. People with low immunity or vitality may suffer from bronchitis if these conditions deteriorate.

[REFERENCE: “Fog-induced Respiratory Responses Are Attenuated by Nedocromil Sodium in Humans – PubMed.” PubMed, 1 Apr. 2001, pubmed.ncbi.nlm.nih.gov/11316646]
Inhaling foggy air is also likely to reduce oxygen intake due to more saturated water droplets. It will put more pressure on the body, requiring more sleep or repair time.
Patients with rheumatism and arthritis experience excruciating pain during foggy weather. The argument dilates that low air pressure on fog days causes inflamed tissues to expand and aggravate the pain. In addition, lower activity and an inclination to hibernate during fogy weather result in joint stiffening and extreme pain in cases of movement.
Effect of fog on Transportation
The most pronounced effect of fog is the loss and delay caused to transportation infrastructure. Its impacts are not only confined to land travel and air operations; marine travel is also severely affected. Fog reduces visibility, causing accidents and loss of life, especially on motorways and highways. Visibility of less than 200 ms is attributed to dense fog and is dangerous for driving. On average, 10 percent of accidents in fog-prone areas, especially multiple crashes, are because of fog. It causes inconvenience for air passengers and considerable economic loss due to cancellations, delays, and diversions of flights if visibility drops below 1.2 km. The fog may cause the termination of shipping operations if visibility drops below 0.5 km.

Dense fog conditions on roads disrupt vision and make it difficult for drivers to see the road, signs, pedestrians, and other vehicles or objects, threatening the lives of passengers.
It’s important to exercise caution and adhere to safety guidelines when dealing with foggy conditions, especially in transportation scenarios, to minimize the potential risks and ensure the well-being of both passengers and operators.
How do I avoid the negative effects of fog?
Keep the air clean. The quantity of particulate matter and pollutants in the air tends to exacerbate the negative effect of fog. The government has to take long-term measures to minimize carbon emissions and regulate the lifestyle of the population, like the timing of industry and traffic on the roads, to lower the pollutants in the air.

Ensure personal protective measures like wearing masks or full-sleeve clothes and staying hydrated.
Drive Safely. The most pronounced effect of fog is the danger associated with driving. Adhere to the following safety tips for driving in fog:
- Drive slowly and keep a sufficient distance from the front vehicle.
- Keep the headlights and taillights on to be visible.
- Use low beam; high beam light will reflect from the fog, further impairing the vision.
- Use the left edge or lines on the roads as navigation aids.
- Never apply sudden breaks to avoid being bumped by an oncoming rear vehicle.
- Use the defroster to keep your windows clear of fog.
Final Thoughts
The effect of fog on life and the environment is a multifaceted phenomenon. While it can pose challenges and risks to transportation and safety due to reduced visibility, fog also plays a crucial role in sustaining ecosystems and biodiversity. It serves as a valuable water source in arid regions, benefiting both flora and fauna. Additionally, fog adds a unique aesthetic quality to landscapes and has inspired art, literature, and cultural traditions throughout history. Understanding and managing the impact of fog on our lives and the environment is essential for promoting safety, preserving delicate ecosystems, and appreciating the beauty and significance of this natural phenomenon.