The problems may be caused by microscopic particles of dust, dirt, soot and smoke released into the air from the diesel exhausts.

But even there tiny particles of dust and grit will soon accumulate on the paintwork and become scratches as you brush by it.

As they descend, the cones of light illuminate tiny particles of dust and haze swirling in the atmosphere.

Small particles of dust can create some vivid sunrises and sunsets, typically causing deep oranges and reds to appear in the sky.

The tiny particles of dust also act as seeds for water droplets to form on, eventually forming clouds that can also help to reduce sunlight.