High-speed winds are lashing down on Delhi and adjoining areas in NCR which include Gurgaon and Noida and the same has prompted authorities to issue advisory statements in regards to the storm in Delhi/NCR. While the India Meteorological Department (Met dept.) had already issued warnings for a thunderstorm accompanied by high-speed winds in the area, the Delhi government as well as Delhi traffic police have also issued directives.
All residents have been advised to try staying indoors during the dust storm in Delhi/NCR and if you are outside at all, it is advised to exercise maximum caution. While you have already been updated with all the precautionary measures that one might take in such conditions, you might as well be thinking about the reasons why and how a dust storm so huge has hit areas like Delhi/NCR, Rajasthan and more.
Here we take a look at how dust storms are formed and what are the reasons behind them.
It is said that as the force of wind passes over loosely held particles and increases its pace, the particles of sand first start to vibrate and then start to saltate. Since they repeatedly strike the ground due to the wind, they loosen and break off into smaller particles of dust that begin to travel in the suspension. On the other hand, at wind speeds above this pace, it causes even the smallest particles to suspend and there will be a population of dust grains which will be moving by a range of mechanisms known as suspension, saltation, and creep.
“The initial saltation between sand particles induces a static electric field through friction. Saltating sand acquires a negative charge which is relative to the ground that in turn loosens more sand particles, all of which then begin saltating. This process is said to double the number of particles which were predicted by previous theories,” a study named ‘Electrostatics in wind-blown sand’ concluded in 2008.
In such situations, particles become loosely held due to drought or arid conditions along with varied wind causes. Gust fronts might be produced by the outflow of air cooled by recent rains from an intense thunderstorm. However, the wind gusts might also be produced by a dry cold front which is a cold front that moves into a dry air mass while producing no precipitation, which is similar to the recent storm in Delhi/NCR.