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Our Beautiful Planet

June 2, 2017

Predicting the unpredictable: 'Red sky at night, sailors' delight. Red sky in the morning, sailors take warning.'

https://p.dw.com/p/2e3D0
Sunset over the Louvre in Paris, April 2017 (DW/T. Rooks)
Sunset over the Louvre in Paris, April 2017Image: DW/T. Rooks

There is more than a grain of truth in many proverbs. These short, pithy sayings are a mirror of the society that uses them and usually communicate an uplifting message: "A friend in need is a friend indeed" or "Great minds think alike."

Inevitably many proverbs are also related to different weather phenomenon: "Every cloud has a silver lining" and "Into every life a little rain must fall." But what about red skies at night?

"Red sky at night, sailors' delight. Red sky in the morning, sailors take warning."

This adage is as old as the hills. It appeared in the bible. Shakespeare used it in 1593 when writing "Venus and Adonis." The saying is also versatile. In a similar version "shepherd" is used instead of sailor, which doesn't change the meaning much; it simply brings the proverb onto dry land.

The uncomfortable truth

Admittedly, weather is a serious topic and in some cases a matter of life and death. It is imperative to know when to plant or harvest crops, how to navigate ships and when best to simply stay home. With little or no way to accurately forecast weather in the past, people grasped at whatever observations or experiences they could to try to understand the weather.

But is there really any meteorological science behind the red skies at night?

Yes. In the morning and in the evening the sun is at its lowest point. Its ray pass through the lower atmosphere at a sharp angle and reflect off water vapor and other particles. Air filled with pieces of dust and particles appears red. Relatively clear air reflects blue. 

A red sky in the evening means that the setting sun is shining through a concentration of high pressure air. Because in much of the world weather patterns move from west to east, this means that good weather is on its way, since high pressure air means pleasant weather.

A red sky in the morning is the opposite. As the sun rises in the east, it illuminates the weather that has already happened. In this case the high pressure area has already passed, which means an area of low pressure is on its way, usually bringing rain.

Channeling the weather

Yet weather is a fickle wonder. It cannot be controlled and can change without notice in seconds. As in centuries past, we can only try to understand it through our observations or experiences.

In the end we don't need to read nature's rainbow language to be able to enjoy it. Red skies at night or red skies in the morning are simply beautiful. The next time you see one, take time to soak it in without thinking about the weather it could bring.

Do you have a picture of a beautiful landscape or something amazing in nature that you want to share with our readers? If so, you can send it to us using the upload tool on our website, or by emailing us at ecoafrica@dw.com. We look forward to hearing from you.