Even though farmers have been burning residue for decades, it is only now that the problem has grown so bad. I believe the record increase in the number of industries and cars is to blame. Throughout most of the world, industries are set up in coastal areas as the sea breeze drives away the polluted air.
The best thing to do is to shift smoke producing factories to coastal areas. It would also help if smoke-producing vehicles are grounded during winter.
Shakir Lakhani
Karachi