A tornado is defined as a violently rotating column extending from a thunderstorm to the ground. The most violent tornadoes are capable of tremendous destruction with wind speeds of two hundred and fifty miles per hour or more. Damage paths can be more than one mile wide and fifty miles long. In an average year, eight hundred tornadoes are reported nationwide, resulting in eighty deaths and over one thousand five hundred injuries. In the body of my essay, I will tell you about types of tornadoes, where tornadoes come from, where and when tornadoes occur, the damage they inflict, variations of tornadoes, and how to detect tornadoes.
There are many types of tornadoes. The average tornado is usually split up into categories based on the strength of the tornado. Most tornadoes, about sixty nine percent 69%, are considered weak, which means they usually last between one minute and ten minutes, have winds less than one hundred and ten miles per hour, and the percent of deaths that occur during these is less than five percent. Strong tornadoes, about twenty nine percent 29%, may last about twenty minutes, have winds between one hundred and ten and two hundred and five miles per hour, and the percent of deaths that are found are about thirty percent of all tornado deaths. The last category for tornadoes is violent ones. With these comes winds greater than two hundred and five miles per hour, they can last about an hour, and have seventy percent of all deaths from tornadoes. Another type of tornado is known as a waterspout. This is a weak tornado that forms over warm water. They are most common along the Gulf Coast and southeastern states. In the western United States, they occur with cold late fall or late winter storms, during a time when you least expect it to develop. They occasionally move inland becoming tornadoes that can cause a great deal of damage and many injuries.
Most tornadoes evolve from energy. Tornadoes come from the energy released in a thunderstorm. As powerful as they are, tornadoes account for only a tiny fraction of the energy in a thunderstorm. What makes them dangerous is that their energy is concentrated in a small area, perhaps only a hundred yards across. Not all tornadoes are the same, of course, and science does not yet completely understand how part of a thunderstorm’s energy sometimes gets focused into something as small as a tornado.
Whenever and wherever conditions are right, tornadoes are possible, but they are most common in the central plains of North America, east of the Rocky Mountains and west of the Appalachian Mountains. Tornadoes can also occur in many other areas of the world as well. They have been recorded in Australia, Europe, Africa, Asia, and South America as well as in North America. They occur mostly during the spring and summer; however, the tornado season comes early in the south and later in the north because spring comes later in the year as one moves northward. They usually occur during the late afternoon and early evening. However, they have been know to occur in every state in the United States, on any day of the year, and at any hour.
The damage from tornadoes comes from the strong winds they contain. It is generally believed that tornado wind speeds can be as high as three hundred miles per hour in most violent tornadoes. Wind speeds that high can cause automobiles to become airborne, rip ordinary homes to shreds, and turn broken glass and other debris into lethal missiles. The biggest threat to living creatures, including humans, from tornadoes is from flying debris and from being tossed about in the wind. It used to be believed that the low pressure in a tornado contributed to the damage by making buildings “explode” but this is no longer believed to be true.
Some variations of tornadoes are that they can be found in the early stages of rapidly developing thunderstorms. This type of tornado is most common along the range of the Rocky Mountains, the Plains, and the Western States. Tornadoes may appear nearly transparent until dust and debris are picked up. Occasionally, two or more tornadoes may occur at the same time.
Today, the development of Doppler radar has made it possible, under certain circumstances, to detect a tornado’s winds with radar. However, human beings remain an important part of the system to detect tornadoes because not all of them occur in situations where radar can “see” them. In addition, ordinary citizen volunteers make up what is called SKYWARN (www.skywarn.org) network of storm spotters who work with their local communities to watch out for approaching tornadoes, so that those communities can take appropriate action in case of a tornado. Spotter information is relayed to the National Weather Service, which operates the Doppler radars and which issues warnings, usually relayed to the public by radio and television, for communities ahead of the storms using all the information they can obtain from weather maps, modern weather radars, storm spotters, monitoring power line breaks, and so on.
These are all important tornado facts and reasons of why this phenomenon occurs. Tornadoes are natural disasters that we can not do anything about, we just have to learn to live with them and be smart about how we approach them. There is no preventing a tornado from occurring so we must merely take all the precautions so we will be safe.
Rosenfeld, Jeffrey O.; Eye of the Storm: Inside the World’s Deadliest Hurricanes, Tornadoes, and Blizzards; HarperCollins Trade Sales Dept, January 1999
Robinson, Andrew,; Earth Shock: Hurricanes, Volcanoes, Earthquakes, Tornadoes and Other Forces of Nature; Themes ; Hudson Ltd., September 1993
Tufty, Barbara; 1001 Questions Answered about Hurricanes, Tornadoes, and Other Natural Air Disasters; Dover Publications, Incorporated, August 1987
Verkaik, Arjen; Under the Whirlwind; Whirlwind Books, March 1998
Miller, Norman; “How A Whirlwind Works”; Geographical Magazine, June 1999
Compton’s Encyclopedia Online; www.comptons.com
SKYWARN Online; www.skywarn.org
/ Pages : 1,023 / 24