One ship drives east and another drives west
With the selfsame winds that blow.
'Tis the set of the sails
And not the gales
Which tells us the way to go.
Like the winds of the sea are the ways of fate,
As we voyage along through life.
'Tis the set of a soul
That decides its goal,
And not the calm or the strife.
-- Ella Wheeler Wilcox
I love this philosophical poem about wind and the murmuring of breezes high in the tops of the aged pines on my place. My daughter Mariah is named after the wind. However, I do have limits when it comes to this force of nature.
When in Alaska I wondered if I could live there for an extended period of time. Wind was a factor that fell in the negative column of my assessment. While Anchorage is protected from the wind, the village of Bethel is on treeless tundra abutting the Kuskoskim River and is exposed to the wrath of the wind.
Part of me wanted to live in Bethel, but I decided I couldn't at that point in my life. I know what I love and I know my limitations. I love trees. I don't do well in darkness. I tire of incessant wind.
Yesterday my friend, Kathy Melby, and I went to the Science Museum of Minnesota's Omnitheater presentation on Earnest Shackleton's 1914 expedition to Antarctica. There we saw winter at its worst. Wind, water and ice captured, locked and then crushed the Endurance, Shackleton's ship. Gale and hurricane force winds played a major role in their saga. The film put my present wintertime woes into perspective. If you're not pleased with our wimpy winter, I recommend an outing to the Omnitheater.
Let's look at some scientific facts about wind.
Wind is air in motion and moves in several ways. The horizontal movement of air is what we feel as wind. The movement is caused by air moving from a place of high barometric pressure to an area of low barometric pressure. Vertical air movement, which we seldom feel or think about, is caused by a fluctuation in temperature.
Wind at its best provides major air exchanges that bring quality fresh air, dries spring soil, aids in lake turnover, cools us on hot days and, of course, allows us to fly kites.
At its worst, wind adds minus double-digit figures to wind chill indexes and spawns deadly, destructive tornados, cyclones, hurricanes and typhoons. Tornado wind speeds can reach 600 miles per hour. Cyclone winds do not move as fast as tornado winds, but they cover a larger geographic area and can be equally devastating. Because of their size and duration, hurricanes and typhoons are considered the most terrible of storms.
Worldwide movements of air reveal interesting patterns. While tornados occur worldwide, the majority take place in the United States and travel in a northeasterly direction. The wind direction within a tornado varies -- counterclockwise in the northern hemisphere and clockwise in the southern hemisphere. Hurricanes appear in the western hemisphere (North America, South America and surrounding waters) while typhoons dominate the eastern hemisphere, the half of the earth east of the Atlantic Ocean.
Tornados, or twisters, hit the Midwest and Gulf states primarily in spring and early summer. Approximately 700 tornados have been reported annually in the U. S. since the mid-1950s. Most last less than an hour and travel an average of 20 miles at speeds of 10 to 25 miles per hour.
Occasionally, tornados travel 200 miles or more at speeds nearing 60 miles per hour, the funnel touching down intermittently and then retreating into the clouds. When a funnel travels over lakes or oceans it is called a "waterspout."
The Beaufort Scale Wind Chart is used to classify wind speed. A numerical range from 0 to 12, respectively, assigns wind into categories from calm to hurricane force. In addition to the Beaufort Scale, meteorologists use other terms to describe wind conditions. Windy refers to wind velocity of 20 miles an hour or more. Squall is wind that increases suddenly in speed to 19 miles an hour (fresh wind) for two or more minutes and then decreases rapidly in speed. Gusty winds change speed suddenly within 20 seconds, in large variations between peaks and lulls. Damaging winds, once called "high" or "strong," are winds that damage vegetation or property.
Knowledge of wind speeds and directions has historically come from tracking the movement of weather balloons. However, the National Oceanic and Atmospheric Administration (NOAA) now has a multi- million dollar network of 30 wind measuring devices called profilers, located in nine central states where some of the wildest weather in the nation is found.
In simple terms, a profiler is a 30-foot square wire grid that beams up radio waves as high as ten miles into the atmosphere. Air movement changes the wave frequency and the changes indicate wind speed and direction variations. Information updates are every half-hour instead of the twice daily weather balloon.
When I think of winds I try to block out thoughts of bitter wind-chill and instead think of more pleasant memories, such as flying kites, soothing summer breezes, sailing and warm poetic philosophy.
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