Climate Control

One of the most surprising things I learned about Thomas Jefferson, when I visited his historic home near Charlottesville, Virginia, was his interest in weather. He kept a daily diary of weather conditions, a practice every student could imitate. By keeping such an annual diary, for example, students could check the dates when they see the first robin. Are northern migrations getting earlier each year? Could this be an indication of global warming?

     Although an individual's record of temperature changes over a lifetime cannot predict a long-term climate trend, an interest in weather has a wide variety of global applications. Young people already are interested in weather and its many facets according to the number of children's books on sun; clouds, storms, lightning, and hurricanes; wind and tornadoes; winter and snow; global warming and climate change; how to dress for the weather; and weather experiments. When my granddaughter was younger, she put snow in a jar, measured it, let it melt, and compared how much "rain" made how much snow. Children also can monitor the direction of wind using weather vanes, windsocks, and flags and record how the temperature changes or a storm develops after wind strengthens. In a trivia contest, I learned that the official measure of wind velocity is taken 33 feet above ground and that a flag flies straight out when wind is blowing at least 25 miles per hour.

     Of course, most students already know how Benjamin Franklin demonstrated that lightning was electricity. Lightning occurs when air can no longer prevent the attraction between oppositely charged drops of moisture in a cloud and the earth. Flying a kite tipped with a metal point into a thundercloud, Franklin watched a door key attract lightning's electric charge travel down the kite string. During a storm, since the static electricity discharge from a cloud seeks out the nearest points on earth, lightning strikes tall trees and buildings. As a practical application, Franklin suggested mounting a pointed metal rod, a lightning rod, on tall buildings to neutralize lightning's electrical charge and therefore prevent buildings from catching on fire.

     Weather has long played an important role in military maneuvers. Armies have attacked with the daily sunrise behind them in order to blind their enemies. Russia's winter defeated Napoleon, just as fog prevented him from knowing British Admiral Lord Nelson's navy had slipped between his fleet and his planned attack on Egypt.

     According to the Bible, even God has worked His will with weather. In the story of Noah and the Ark, God showed His displeasure with man's evil deeds by causing a flood that destroyed everything on earth. After the waters subsided, God said that a rainbow would be a sign that He would never again use a flood to destroy the earth. Some Czech citizens still honor Our Lady of Hostyn and the Christ Child in gratitude for the fierce lightning sent in response to prayers for prevention from a Mongol attack in 1241.

     In her book, Weather of the Future, Heidi Cullen tells how an ambulance driver named Lewis Fry Richardson set out to forecast battlefield weather conditions in World War I. He used values for the atmosphere's pressure, temperature, density, water content, and east, north, and up wind in 12,000 columns (3 degrees east-west and 125 miles north-south) in Central Europe. Without a computer, however, his calculations required too much time to be of any use for generals, and the data he used were too incomplete. Nonetheless, his book, Weather Prediction by Numerical Process, made a groundbreaking contribution to meteorology. Students like Richardson, who develop an interest in predicting the weather, might get a start on a career by reading Instant Weather Forecasting by Alan Watts. Using pictures of various skies, he explains his technique for relying on cloud studies that are more accurate for countries in the temperate latitudes than in the interior of Africa and the Caribbean.

     Research by the U.N.-sponsored Intergovernmental Panel on Climate Change (IPCC) is raising major concerns about the effects of rising earth surface temperatures, higher sea levels, and decreasing glacier melt and snow cover. Methods for attacking these problems, which are attributed to the atmospheric concentrations of greenhouse gases from fossil fuel emissions of carbon dioxide, methane, and nitrous oxide, are suggested in the earlier blog post, "A Healthy Environment."