The fifth of November we can’t forget,
As colourful explosions light the sky;
But rocket residue can cause a threat,
Especially if humidity is high.
The smoke and aerosols affect your eye,
With visibility a quarter less
On average, but when conditions are dry.
With more moisture less vision will egress,
And warnings should be issued to reduce distress.
This is a Spenserian stanza about a recent study, which investigated the effect of bonfire night on visibility, and found that on average it is reduced by approximately 25% across the country, but that the visibility reduction is more significant when the atmospheric relative humidity is high. More should also be done to issue poor visibility warning in advance, especially in weather conditions that are likely to exacerbate poor visibility.