The Perfect Sunset

by Floyd Maxwell, BASc
Principal, http://www.just-think-it.com

Part of the reason is their relative rarity. I mean, if they happened every day, what would be so neat about them?

Another reason is that we associate things with a sunset.

The typical sunset fantasy is: The sun goes down over the horizon with pretty orange and red colors. The horizon is at sea level, with the sunset's effects filling the sky. The sunset is seen from a palm-tree dotted shoreline. In a tropical part of the world.

This fantasy is so pervasive that most of us are convinced that the *best* sunsets happen in a tropical place like Hawaii, or Tahiti. Increasing our desire to be there.

But is this in fact the case?

Well, what are the ingredients needed for a good sunset?

Most obvious is the need for the sun itself. Clouds in front of the sun certainly preclude even the remotest possibility of a sunset. From this first requirement it is easy to see how we associate sunsets with warm, tropical, sunny places.

But what else is needed? Believe it or not, clouds!

In fact, the *best* sunsets will *always* have clouds. Just not on the horizon. Clouds on the horizon will cover the sun when it is at its lowest point, and this is where the rarest colors are produced -- pinks, reds, mauves and purples.

Still wondering why clouds are essential to a great sunset?

Because they provide variety of color. Without them, one has a perfect graduation of color from say light orange above to dark orange on the horizon, but with no other colors mixed in. No highlights. No contrast. This kind of "graduated color" effect was popular for a while (late Windows 3.1 software) as a background color while a program was installed. Like I said, not very interesting.

But mix in some clouds and you have instant variety.

Low clouds will get dark the soonest. High clouds will stay sunlit the longest and have the lightest shades.

Ok, so a mixture of low, medium and high clouds is best?

No, it is not that simple.

First of all, as mentioned, low clouds near the horizon can block the sun. And too many clouds, or an overly dense cloud cover, will mute much of the effect. And at any time a misplaced cloud can spoil the effect where you happen to be standing.

In my limited cloudy sunset studies -- I live on the wet west coast of Canada after all -- the finest cloudy sunsets have occurred when the clouds where in "horizontal" (north-south) ribs, with gaps between the ribs equal to or greater than the width of the cloud ribs. Also, in the very best one I ever saw, the clouds were all at the same height, and the ribs were the most uniform. It was so spectacular, I probably think about it once a year, usually when viewing the current "best" sunset. And I saw it while walking home from work in the heart of downtown Vancouver, BC. A most unlikely spot indeed.

Well, there you have it. Another wild theory.

But that is just the point. This is not an opinion, but a theory. And that means it can be tested.

Be my guest.

And enjoy a cloudly sunset!

Here is a sunset image you could use as your "Desktop Wallpaper", the background for your Windows. Click on the image that matches the resolution of your desktop (the most common size is 800x600), and then right-click on the image and select "Set as background".

Choose your image size:  640x480   800x600   1024x768   1600x1200