Yosemite YEBlog @ yexplore.com

We’ve had a recent string of less than stellar weather for our tours recently, but it has not dampened our spirits the least bit.  There’s a saying in Hawaii: “No rain, no rainbows.”  That’s not exactly the case in Yosemite because you would not see waterfall rainbows without sun.  But like Boon said about Bluto and his Germans “Forget it, he’s rolling”.  Our last couple of trips up the Mist Trail have provided us with excellent opportunities to photograph rainbows. Yesterday, we had sunny skies in the am before the snow came.

What is a rainbow and how does it form?  There are several ways to explain the phenomenon.  None of which would have been understood by the Delta House, but here is one from The Young Peoples Trust for the Environment website:

A rainbow is sunlight spread out into an arc of colours and seen by your eyes when the sun shines through water droplets.

Where is the sun when you see a rainbow?

When looking towards the rainbow the sun is always behind you.

What makes the bow?

Water droplets and sunlight act upon each other. The droplets are round and it is the way that the sun’s rays hit the droplets that causes the colours of the light to spread out in an arc.

What makes the colours in the rainbow?

Sunlight always looks white but in fact, is made up of seven colours – red, orange, yellow, green, blue, indigo and violet. The rainbow is a whole band of colours and goes even beyond the colours that the eye can see.

What makes a double rainbow?

If we follow the path of a ray of sunlight as it enters the raindrop, some of it comes back to us. A part of the ray enters the raindrop for a second time and travels along inside the droplet until it comes out once again. That is why we sometimes see the primary rainbow which is produced by one internal ‘reflection’, and the secondary rainbow which is fainter and produced by the second ‘reflection’.”

Information sources: www.unidata.ucar.edu