@glcarlstrom the build-up / deployment had to be done to add credence to the threat of ground invasion...could end up being used merely as a pressure tactic in the negotiations and need not indicate intent of actual boots on ground
@anujdhar there are multiple causes all happening at the same time....1. stubble burning 2. crackers 3. local vehicular pollution 4. temperature inversion and still air
each needs to be controlled