The recent dust storms that originated in the Middle East not just impacted the neighbouring areas but also had a significant effect on multiple states across India. The storm disrupted daily life in Pakistan, while Indian cities like Mumbai, Ahmedabad and Pune have witnessed ‘very poor’ to ‘severe’ air quality since Sunday.

Experts say that, on average, around 44 billion pounds (20 teragrams) of dust is present in the Earth's atmosphere at any given time. And when they blow as concentrated streams atmospheric current, they can pose significant health risks. Here’s a quick explainer on what they are and how they impact India.
What triggers dust storms?

Local thunderstorms and low-pressure areas produce strong winds in arid regions, and these winds pull dust from the ground up into the air, and a dust storm is born! The wall of dust created by a dust storm can be miles long and several thousand feet high.

Most of the world's dust storms occur over the Middle East and North Africa. Depending on the wind intensity, they may spread across long distances.

Geography, as well as plant diversity and abundance, play a critical role in the birth of dust storms. For instance, flat areas with sparse vegetation or dunes are most prone to such storms since these features allow winds to build momentum.
What are the consequences of dust storms?

Although dust storms last only for a short period, the particles of dust that linger in the air can cause problems for days or even months.

The United Nations' Asian and Pacific Centre for the Development of Disaster Information Management publishes 'Sand and Dust Storms Risk Assessment in Asia and the Pacific' report. The 2021 report claims that over 500 million people in India, and over 80 per cent of the population from Turkmenistan, Pakistan, Uzbekistan, Tajikistan and Iran, are exposed to medium and high levels of poor air quality due to sand and dust storms.

Particles larger than 10 micrometres (μm) can cause skin and eye irritations or infections, while smaller inhalable particles may trigger respiratory disorders like asthma, tracheitis, or pneumonia. Besides, extreme dust storms can also hamper crop yields, especially cotton, and pollute rivers. They also lead to a significant drop in visibility, hampering road, railway, and air transport.

However, these storms also transport nutrients like iron and phosphorous to parts of the ocean that lack them and can prove highly beneficial for marine biomass. Saharan dust particles are thought to fertilise even the Amazon rainforest!
Impact of the present storm on India

On Saturday, a westerly trough combined with humid weather triggered a dust storm in Pakistan's Balochistan region. The dust winds blew from southern Pakistan and the Arabian Sea and reached Gujarat's Kutch and Saurashtra by evening. IMD's weather station at Dwarka reported 400-metre visibility, and Porbandar reported a visibility of less than one kilometre.