“Clouds are classified by form, appearance, composition and height. There are only two shapes -- either stratus, which are sheet like, fibrous, or layered, and cumulus, clouds that are piled up or accumulated in appearance, looking like rolled, cottony or cauliflower shapes. Height breaks clouds into four families. A are high clouds, having a lower level of 20,000 feet above the ground. B are middle clouds with a base of 6,500 feet, C are low clouds with a base near the Earth’s surface, D are clouds of vertical development, having an average lower level of 1,500 feet and an upper level of high clouds. Meteorologists use the two forms and the height classes extensively to predict the future weather patterns for an area.”
This is so simple and logical that it is remarkable how long the system took to develop. I’ve been reading a lovely book (I mean that the actual book is gracefully attractive.) called “The Invention of Clouds” by Richard Hamblyn, exploring the work of Luke Howard, a quiet young Quaker, whose system prevailed over many more inventive and fantastic ideas. It’s also a good overview of “the era of taxonomy” in the 19th century when the cultural preoccupation was sorting and naming all natural phenomena. It has recently been argued that modern technology has supplied the world (in the US, anyway) with excesses of creativity. In the 19th century there was something similar, fortunes being made from industry which allowed some people to concentrate on developing the sciences. This preoccupation has become a subject for movies like “Insects and Angels,” “The Governess,” and “The French Lieutenant’s Woman,” which latter manages to lay that 19th century pattern over against our modern preoccupation with virtual worlds.
The key to the taxonomy of clouds was, of course, perceiving what was going on up there in the first place, something like the key to fossils requiring the surrender of convictions about the creation of the Earth. Clouds meant understanding that air is an ocean in which the forces of convection and gravity fight it out in layers and whorls powered by temperature as the great currents course across water and land.
Nowhere is that more obvious than here on the east slope of the Rockies where we are in the cross-hairs of the Pacific fronts coming in wet against the western side of the mountains, piling up in a storm shelf that looks like a second virtual range of mountains behind the actual stone ramparts and turrets, and then having dumped a load of moisture into the forests, scraping and dragging onto the prairie where there is barely enough rain left for grass. This coming in left-to-right, while the Arctic cold comes down the east side of the Rockies which act as a curb directing the cold south along the Old North Trail. Thus any cloud higher than maybe 4,000 or 5,000 feet in fall or spring easily becomes snow, stored in a deep “pack” all through the winter to melt in summer as cold trout streams.
We are discovering that the idea of “global warming” is not about temperature rising, but about energy, for the nature of “warmth” is the faster gyration of molecules driven by heat. We do see warming on the prairie and in the mountains -- the bunny-like little pikas keep having to move farther up the mountains to make their grass storage systems work (they cut it and stash it in holes) -- but what we are also seeing is an increasingly faster and more potent sequence of fronts coming through. The wind, oh, the wind. What a rush! Driving along with its fronts, tearing away roofs and tipping over railroad trains.
A global jet stream goes overhead, moving north in the summer, south in the winter, and occasionally sinking vertically to near the ground. These two movements have much to do with our crops, giving rain that grows them, then hail that destroys them. Overhead we hear big coast-to-coat airliners hitchhiking on that airstream to save fuel.
Our clouds here are often complex: the alto-cirrus high ice wisps in the background, cumulus piling up in dramatic marble forms that mean thunder and lightning, and maybe, especially in the morning, a little dark stratus striping near the ground after exhaling from wet earth soaked by those cumulus dropping their burdens. I’m just beginning to understand.
One of my aids is another book, a picture book. Called simply “Clouds", by Eric M. Wilcox, it showed up on the steady mercantile jet stream of remaindered books. It was sold out at Daedalus so I bought the last copy at Powells. (One sometimes wonders whether such popular books are remaindered too quickly.) I liked it so well that I’ve been packing it around the house and nearly lost it. It turned up in a stack of to-read books, which get higher in the summer because, well, I’m out reading the clouds. In fact, the ultimate aid to understanding clouds might be to paint them. I have a canvas that seems suitable and I think I’ll begin by making a portrait of Valier fashioned after John Constable’s (1776-1837) painting of Salisbury. It won’t make it into the Louvre, as Constable’s did.
One of Luke Howard’s competitors, Thomas Forster, claimed that cirrus, cumulus, etc. were too Latinate for artists to understand. He suggested his own categories: curl-cloud (cirrus), stacken-cloud (cumulus), fall-cloud (stratus), sonder-cloud (cirrocumulus), wane-cloud (cirrostratus), twain-cloud (cumulostratus), and rain-cloud (nimbus). No reaction from artists is recorded, but as Forster (who was Catholic) continued to elaborate, valorize, historicize and otherwise ornament Howard’s plain Quaker seven categories, the two -- originally friendly -- became separated. One of the most salient characteristics of clouds is their ability to evoke human minds into projecting their beliefs on the sky. No less than the stars do the clouds invite stories of transcendence. But clouds affect us more than stars do, pelting us and muffling us and sending floods roaring down the valleys to wreak havoc. It’s in our interest to keep a close eye on them.
Looking towards Valier from Lake Francis.
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