Dust storms arrive months before the start of the city's traditional ‘pollution season’
Smog, more toxic than monitoring devices can measure, has covered the Indian capital this week, months before the start of Delhi's traditional “pollution season”.
A thick haze was visible across the city since Tuesday and some government pollution monitors have recorded concentrations of 999, the highest they can measure, as dust storms kicked up in the nearby state of Rajasthan covered the region.
Although clouds of dust and sand were blamed for the immediate spike in pollution levels, the sight of dense smog engulfing Delhi months before winter has underscored a growing awareness that harmful air is a year-round problem for the city. city.
Air quality in Delhi generally begins to plummet in October when slower winds and colder temperatures trap pollutants closer to the ground.
But data released by the government's Central Pollution Control Board shows that air quality has been classified as "very unhealthy," with index scores of up to 270, every April and May for the past three years, or since the authorities began to compile and publish the statistics.
Only one day in April or May of the last three years was the air classified as “good”: on April 12 of this year, when levels dropped to 99. “This clearly shows that this is also a summer problem”, said Aishwarya Sudhir, an independent researcher who studies air quality in India.
Authorities ordered a halt to all construction in the capital and its satellite cities until the weekend to reduce pollution levels, and doctors have advised people to stay indoors as much as possible.
Forecasters said the presence of a layer of dust across the city is also trapping heat, sending temperatures in excess of 40 ° C.
Concern over North India's air quality crisis is generally more acute after the Hindu festival of Diwali in autumn, when hundreds of thousands of Indians throw firecrackers that combine with existing pollutants to form a poisonous haze over the region that persists for months until temperatures cool. Public health experts said pollution levels on some days in November last year were the equivalent of smoking 50 cigarettes a day.
India, home to 14 of the 20 most polluted cities in the world, has the highest rate of respiratory illness of any country. A leading lung specialist, Arvind Kumar, says that the cancer patients Delhi sees are younger, more often female, and more likely to be non-smokers than those outside the city.
Children are the most vulnerable: a 2015 study found that approximately half of the 4.4 million schoolchildren in Delhi suffered from delayed lung development and would never fully recover.
But the pressure on local and central governments to act normally wears off along with the air in February when warmer temperatures help thin the smog.
Sudhir said this week's pollution spike was a wake-up call because Delhi's air is rarely safe. "Polluting activities continue in the city through the summer, including construction, allowing road dust to linger, the operation of coal-fired power plants and other things," he said.
According to an action plan in force since January 2017, the pollution levels registered this week should have led to the denial of the entry of trucks into the city, the closure of brick kilns and other polluting industries and the prohibition of using diesel generators.
However, the government appears to implement only some of these measures, and only in response to public protests, he said.
"We tend to act only when it is an emergency," he said. “There were forecasts that dust storms would sweep across the region. They should have acted in these weeks, not when it got so severe. "
Original article (in English)