Satellite image courtesy of NOAA
Springtime may bring the promise of April showers and May flowers. But it also brings the possibility of extreme weather, including violent thunder-storms and tornadoes.
Most countries experience tornadoes, but they occur more frequently in the United States, east of the Rocky Mountains, than anywhere else on Earth. On average, almost 1000 tornadoes touch down in the U.S. each year, leaving in their wake destruction and sometimes death.
How Tornadoes Form
Thunderstorms form when warm, moist air collides with an eastward moving cold front. These storms often produce strong winds, damaging hail, and even tornadoes. A tornado is a rapidly rotating column of air that extends from the base of a thunderstorm to the ground. A tornado’s characteristic funnel shape is visible because of water droplets, dust, and other debris that are caught up in the swirling air.
Measuring the Force of a Tornado
The force of a tornado is measured using the Fujita Scale, which ranks tornadoes based on the level of damage caused by the storm. The scale ranges from F-0 for a storm that causes light damage to F-5 for a storm that leaves incredible damage.
Mapping Tornado Frequency in the U.S.
a) Distribute to students copies of the handout. Have student examine the data in the handout to identify which states average the highest number of tornadoes each year.
b) Next, distribute blank U.S. maps. Have students construct choropleth maps showing the frequency of tornadoes by state in the U.S.
c) Explain to students that areas with a high occurrence of tornadoes have been given the nicknames of “Tornado Alley” and “Dixie Alley.” Have them refer to their maps to locate these two regions that experience many tornadoes each year.
Extending the Activity
Divide the class into three groups and assign each group one of the following research topics. When students have completed their research, have each group report back to the class.
i. Structure of a tornado
ii. Fujita Scale
iii. Tornado Alley/Dixie Alley
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A Virginia eighth grader trekked to the top spot of the 2014 National Geography Bee.
Did you miss the show, or want to hear the questions again? View the final round of the National Geographic Bee held on May 21, 2014.
The National Geographic Bee is this May. Are you ready? Learn how to prepare for the competition with How to Ace the National Geographic Bee, which includes a variety of questions actually used in past Bees, and The National Geographic Bee Ultimate Fact Book: Countries A-Z, chock-full of all the facts kids need to know to become a geography expert.
Each year students travel from across the United States to Washington, D.C. to compete in the ultimate test of geographic knowledge: the National Geographic Bee.
Quizzes to Go
Do you have what it takes to be the next National Geographic Bee Champion? Find out the fun way with the new GeoBee Challenge! Three types of game play make sure you really know your stuff and never get bored.
Google Earth Presents
Virtually travel anywhere with the Google Earth team before you actually hit the ground. Geography does matter!
Teachers can use these activities in the classroom to prepare students for the bee!
Simply memorizing terms and place locations can be tedious and even boring. One solution is to make the task fun with an atlas-based scavenger game.
The movement of people, goods, or ideas from one place to another is a process known as diffusion, which plays an important role in shaping the characteristics of where we live.
Springtime brings the possibility of extreme weather, including violent thunderstorms and tornadoes.