082 Laboratory 08: Clouds

SUNGLASSES DAY! Bring your sunglasses today! Weather permitting we will be observing clouds.


How accurately can you draw a specific type of cloud?

What am I?

I bring fresh showers for the thirsting flowers,
From the seas and the streams;
I bear light shade for the leaves when laid
In their noonday dreams.
From my wings are shaken the dews that waken
The sweet buds every one,
When rocked to rest on their mother's breast,
As she dances about the sun.
I wield the flail of the lashing hail,
And whiten the green plains under,
And then again I dissolve it in rain,
And laugh as I pass in thunder.

I sift the snow on the mountains below,
And their great pines groan aghast;
And all the night 'tis my pillow white,
While I sleep in the arms of the blast.
Sublime on the towers of my skyey bowers,
Lightning, my pilot, sits;
In a cavern under is fettered the thunder,
It struggles and howls at fits;
Over earth and ocean, with gentle motion,
This pilot is guiding me,
Lured by the love of the genii that move
In the depths of the purple sea;
Over the rills, and the crags, and the hills,
Over the lakes and the plains,
Wherever he dream, under mountain or stream,
The Spirit he loves remains;
And I all the while bask in Heaven's blue smile,
Whilst he is dissolving in rains.

The sanguine Sunrise, with his meteor eyes,
And his burning plumes outspread,
Leaps on the back of my sailing rack,
When the morning star shines dead;
As on the jag of a mountain crag,
Which an earthquake rocks and swings,
An eagle alit one moment may sit
In the light of its golden wings.
And when Sunset may breathe,
from the lit sea beneath,
Its ardors of rest and of love,
And the crimson pall of eve may fall
From the depth of Heaven above,
With wings folded I rest, on mine aery nest,
As still as a brooding dove.

That orbed maiden with white fire laden,
Whom mortals call the Moon,
Glides glimmering o'er my fleece-like floor,
By the midnight breezes strewn;
And wherever the beat of her unseen feet,
Which only the angels hear,
May have broken the woof of my tent's thin roof,
The stars peep behind her and peer;
And I laugh to see them whirl and flee,
Like a swarm of golden bees,
When I widen the rent in my wind-built tent,
Till the calm rivers, lakes, and seas,
Like strips of the sky fallen through me on high,
Are each paved with the moon and these.

I bind the Sun's throne with a burning zone,
And the Moon's with a girdle of pearl;
The volcanoes are dim, and the stars reel and swim
When the whirlwinds my banner unfurl.
From cape to cape, with a bridge-like shape,
Over a torrent sea,
Sunbeam-proof, I hang like a roof,--
The mountains its columns be.
The triumphal arch through which I march
With hurricane, fire, and snow,
When the Powers of the air are chained to my chair,
Is the million-colored bow;
The sphere-fire above its soft colors wove,
While the moist Earth was laughing below.

I am the daughter of Earth and Water,
And the nursling of the Sky;
I pass through the pores of the ocean and shores;
I change, but I cannot die.
For after the rain when with never a stain
The pavilion of Heaven is bare,
And the winds and sunbeams with their convex gleams
Build up the blue dome of air,
I silently laugh at my own cenotaph,
And out of the caverns of rain,
Like a child from the womb,
like a ghost from the tomb,
I arise and unbuild it again.
- Percy Bysshe Shelley (1792-1822)

In previous laboratories we have explored mathematical models, physical processes, and hypothesis testing. Laboratory eight has a different focus. Laboratory eight focuses on observation, classification, and naming. Science has many fields that focus on careful observation and labeling. The ability to observe and accurately record observations are valuable scientific skills. Science has long depended on accurate and careful drawings of objects and phenomenon. The second part of this laboratory focuses on observation of clouds and attempting to accurately capture a cloud.

Among all animals, only humans appear to attempt to name objects in their surroundings. Western science has spent a great deal of effort on naming and classifying objects and phenomenon. Western science is not the only system that has produced naming and classification systems. The first part of this laboratory focuses on human penchant for naming.

Data table: Weather words

For this laboratory the data tables will be tables of weather words. Working as a class on the board our task is to assemble a list of weather words in the different languages of Micronesia. Words such as sky, cloud, fog, rain, wind, thunder, lightning, morning dew, storm, typhoon, and rainbow. Is there only one word for each or many words? In English rain words include drizzle, mist, downpour, precipitation, shower, and deluge. Lightning is described sometimes by modifier words such as bolt, spear, and flash. Thunder includes variations such as "rolling thunder." Is there more than one kind of cloud? Do the languages of Micronesia include such distinctions?

In class we will brainstorm and share as many weather words as we can. For your table [d] [t] in your own laboratory report you only need to include English and your own language. If there are words in your language that you do not know, ask other speakers of your language for help!


Hamlet: Do you see yonder cloud that's almost in shape of a camel?
Polonius: By the mass, and 'tis like a camel, indeed.
Hamlet: Methinks it is like a weasel.
Polonius: It is backed like a weasel.
Hamlet: Or like a whale?
Polonius: Very like a whale.
- Hamlet, Act iii Scene 2, William Shakespeare, 1602

Prior to 1800 clouds were seen as ephemeral, ever changing, impermanent, and thus difficult to categorize or name. In 1802 an Englishman named Luke Howard developed a systematic way to name clouds. Impressed by the Latin naming system designed by Carl von Linné for classifying plants and animals, Howard devised a Latin-based language system for classifying and naming clouds. Howard's system made sense to scientists. With some modifications, this is the system the world uses to this day. The descriptions are Howard's original descriptions.

  1. Cumulus: Latin for "heap." Convex or conical heaps, increasing upward from a horizontal base.
  2. Stratus: Latin for "layer." Widely extended horizontal sheets.
  3. Cirrus: Latin for "curl." Flexuous fibres extensible by increase in any or all directions' - could also be described as "wispy."
  4. Nimbus: Latin for "rain." Systems of clouds from which rain falls (usually appear dark grey).

Howard extended his system with descriptions for unusual types of clouds.

One modification has been to add a prefix to the middle and high level clouds. Thus we now speak of altoculumulus, altostratus, and cirrostratus clouds. Alto- refers to middle level clouds, cirro- to the highest level clouds. Low clouds get no prefix. Some clouds have bottoms at the low level and tops at the high level. These are vertically developed clouds and usually produce precipitation. These clouds are usually cumulonimbus clouds, a term that combines two of Howard's cloud terms. You and I think of the largest cumulonimbus as clouds that produce heavy rain, wind gusts, and occasional lightning and thunder.

Here on Pohnpei the top of our ridges are 700 to 800 meters high (2000 to 2500 feet). The bottoms of cumulus clouds are often also around this high. Cloud bottoms can be lower, and when the cloud reaches the ground the term used is "fog."

A second modification is that Howard's extended cloud names are often now used to modify one of the four basic cloud types. Cumulis humilis and cumulus congestus are examples of this naming system.

Data display: Cloud observation and drawing

Each student will produce as accurate a drawing of actual clouds as the student can accomplish. Here the goal is observing carefully and trying to accurately capture a realistic image the major cloud types. The drawing should include cumulus humilis, cumulus congestus, cumulus castellanus, altocumulus, and cirrus. Lab partner pairs will have to share an art set kit.

Initially we will observe clouds as carefully as we can, making any necessary sketches on eight and half by eleven paper before returning to the lab room to work on actual drawings.

Data analysis [a]: None

Conclusion [c]: None

Instructional note: This laboratory is accompanied throughout the term by occasional cloud spotting exercises starting from the first day of class. On days when the sky presents a useful mix of cloud types, the class goes outside for a few minutes at the start of class and is shown the various cloud types present. After this laboratory, the outside forays are done as a "cloud quiz" where students have to correctly identify the cloud type pointed out by the instructor in a written "pop quiz."