Images taken from space show the smog suffocating Lahore

At first you can’t see it, but you can feel it. You can smell that something is burning. The smell intensifies as the temperature drops.

Then the smoke and fog begin to envelop you and the city around you. You can see it now. You’re walking through the smoke, with a thick ceiling over your head.

If you’re not wearing a mask, or if you lower it for a moment, you immediately inhale the bitter air.

Your throat may start to itch and hurt. As the situation worsens, you start sneezing and coughing. But it’s worse for others: children, the elderly, people with breathing difficulties. The hospitals know to expect an influx.

Lahore and its 13 million inhabitants have been suffocating for a week; the air quality index has exceeded the 1,000 mark several times this month – any value above 300 is considered dangerous.

The Pakistani authorities have been quick to respond to the crisis, the scale of which is unprecedented, even in a city that has to cope with smog at this time of year.

Schools are closed, workers are being asked to stay at home and the population is being asked to stay indoors as part of a ‘green lockdown’. Motorbike rickshaws, heavy vehicles and motorbike parking are also banned in sensitive areas.

The smoke that enveloped Lahore, in the Pakistani province of Punjab, is visible from space, as is part of the cause.

Satellite images from the US space agency NASA show both the thick layer of smog and the multiple concentrations of fires in the region between the Indian capital, Delhi, and the Pakistani city of Lahore.

The same image, taken six weeks earlier, shows clear skies and, above all, far fewer fires.

One of the main causes of smog is the burning of stubble after harvest by Pakistani and Indian farmers, a quick way of clearing their fields in preparation for the next harvest.