As dense fog has been affecting normal life in Kashmir for the past 5 days, experts and Indian Meteorological Department (IMD) data suggests that conditions favourable for fog have increased after the floods of September 2014.
Suspension of particles in the atmosphere is one of thereasons causing fog, say experts.
In December 2014 – three months after Kashmir witnessed itsworst-ever deluge – the summer capital Srinagar was engulfed in a thick fog for9 days. This as per IMD data is the highest number of fog days Srinagar haswitnessed since December 2008.
"Ever since I took over the affairs at the MeT Department in2006, the flood year was the worst fog hit. However, this December is thesecond highest recorded fog hit. But intensity of fog this time is evenstronger than that of December 2014," Director MeT, Sonam Lotus, told GreaterKashmir.
As per IMD data, the firsttime thick fog was experienced in the last decade during December was in 2008with 4 fog days experienced in Srinagar. From 2009 to 2013, there were no suchdays when thick fog was witnessed in the Valley.
"During last one decade Srinagar has been prone to conditionssuch as haze and mist but thick fog, such as the one experienced recently is aphenomenon which has evolved only post 2014 floods," say MeT officials.
Even in 2017, Srinagarwitnessed 7 fog days which had resulted in disruption of air traffic atSrinagar Airport.
"After the flood year, conditions favourable for fogformation have picked up. There are three main conditions that are beingfulfilled to make fog engulf the low-lying parts of the Valley especiallySrinagar and Budgam: The winds remaining calm, minimum temperature constantlyremaining below 2 degrees Celsius and strong temperature inversion," saysLotus.
Shakil Romshoo, Head of Department, Earth Sciences, KashmirUniversity explains: "In a normal process, temperature decreases with altitude,but in case of temperature inversion temperature increase with altitude. Thistemperature inversion develops a water vapour in which pollutants get trappedwithin the planetary boundary layer which causes the fog."
Romshoo says that post 2014 floods, a lot of sedimentarymatter has deposited all across the Valley, which down the years has beenadding to the foggy conditions.
"The particulate matter in air for last 5 days in Kashmirhas been much more than the normal standards, causing the fog," he says. "Aplanetary boundary layer, which has come downwards, does not allow pollutantsto escape from the Valley. These pollutants are trapped which raises the foglevels," says Romshoo.