Every so often a little bit of colour catches your eye, here by the coast of Ireland I noticed every breaking wave and its spray carrying a rainbow of colour towards the white cliffs of the Antrim Coast.

Rainbows are usually fleeting, relying on a mixture of sunshine and water vapour meeting at the correct angle to create the separation of light into its constituent wavelengths - for us we see the visible spectrum of red, orange, yellow, green, blue, indigo and violet.

Rainbows can occur anywhere, as seen here in the wave spray or on top of a mountain in a ringed glory, in urban settings and in fine autumnal scenes.