Article 2 Module 1

Air bubbles while diving

AIr bubbles while diving

Uneven air masses create white color

Keep in mind that it is the air bubbles that reflect the white light back. It is not water bubbles. 

Light refracts at different angles between the air bubbles and the water holding the bubbles in place.

This chaotic bouncing around of light prevents light from going through. Enough of the light is reflected back to us, making the bubbles look white.

In the image above, the multitude of air bubbles produced by scuba divers will show up as white.

When the production of the bubbles ceases, the white color dissipates.

An angry crab spluttering and foaming at the mouth?

It's not only dogs and cats that foam at the mouth. Even crabs - forcing air out of their gills - will produce foam when out of the water.

The featured image shows a sputtering crab.

Foaming at the mouth:

Have you heard the expression "foaming at the mouth" or "spluttering" or "frothing"?

Colorless saliva turns white as breath is forced through the liquid in the mouth.

The result is white foam bubbling or spluttering out.

For some animals, like dogs, frothing saliva could be a sign that they are anxious or overheated.

A combination of panting, hyperventilation, and excess saliva will lead to air-bubble-laden frothy and white saliva.


A disorganized mass of air bubbles held in place by water will reflect light.

This is the whiteness you see in foam.

Picture credits:

  1. devra . Spittling crab in Morro State Park Marina. This crab was foaming at the mouth. Flickr photo-sharing. Taken July 5, 2010.
  2. Andreas Bjärlestam Bubbles . Flickr photo-sharing. Taken July 25, 2008.