Pictures in the sky | The Knoxville Focus

Stories in this Week's Focus

By Rosie Moore

I am learning how clouds form. What brought this curiosity on about clouds? I was thinking the other day how many cloudy days there have been in this year of 2015. It seems like a lot. I can’t really remember the sun shining for many consecutive days in a row. Most people know that there are three forms of clouds: cirrus, cumulus, and stratus. Here are six steps on how clouds are formed.

1. Light from the sun hits the surface of the earth. A large part of the solar radiation is absorbed by the ground and gradually heats it up.

2. Constant heating reaching the surface of the ground causes air to heat up. The heated air becomes lighter, which causes it to rise above the cooler air which lies above it. This process is called convection.

3. Rising hot air is pushed further upward by wind blowing over terrain such as mountains, or over cliffs into land from the sea. This process is called orographic uplift. Wetter areas are generally found near high terrain features, as the air cools at a quicker rate around these areas.

4. Air is also forced to rise at a weather front. This is due to the differing air masses of the two weather fronts. At cold fronts, cold air is pushed under warm air, forcing it upward and at a warm front, warm moist air is forced up and over the cold air. This process is called convergence or frontal lifting.

5. Clouds begin to develop in any air mass that becomes saturated. Saturation point is reached when the air reaches its frost point. At this point, air gradually cools, preventing it from rising any further. Water vapor molecules within air begin to clump together.

6. Water vapor condenses to form cloud droplets or ice crystals. This can be at various heights, which creates variety different cloud systems. Clouds contain millions of droplets of water or ice, depending on the temperature, which are suspended in the air.

I apologize for the science lesson but I thought it was interesting and I hope it was interesting to my readers. Now, for the pictures in the sky. Look up and you will see many different shapes and forms that are caused by your imagination. Every person will see something different from another person. My cloud that looks like a sheep may look like a dog to another person. A friend of mine told me when I was young (a boyfriend, to be exact) that if I lie on the grass and put my feet up I can be “walking on the clouds.” That is a dreamy thought.

William Cowper, the poet, says it best:

“God moves in a mysterious way

His wonders to perform;

He plants His footsteps in the sea,

And rides upon the storm.

Deep in unfathomable mines of never-failing skill

He treasures up His bright designs,

And works His sovereign will.

Ye fearful saints, fresh courage take,

the clouds you so much dread are big with mercy

And shall break in blessings on your head.”

Remember, clouds are big and merciful, but they shall pass away.