This is a short video on tornadoes published by The New York Times as a follow-up to the catastrophe in Moore on 20 May.
Watch the video and answer the questions below about it.
The activity is suitable for Intermediate students.
1 How fast were the winds in Moore?
2 Which factor plays a big part in measuring how devastating a tornado will be?
3 What's the main difference between a tornado and a hurricane?
4 What does '15 minutes' refer to?
5 What key ingredient in the atmosphere do tornadoes require?
To check your answers you can read the transcript below.
This is Henry Fountain for the New York Times. There’s still a lot scientists don’t know about tornadoes. But here’s some of what they do know.
The tornado in Moore was rated a 5 at the top of the enhanced Fujita scale. The tornado was initially rated a 4, but analysts determined that the damage to homes, commercial buildings and trees was caused by wind speeds over 200 miles an hour, making it a category 5.
Factors like population density play a role on how deadly a tornado will become. The last time we saw a category 5 tornado was in 2011. It tore through the city of Joplin in Missouri and killed over 150 people.
While scientists are able to predict with some precision the track and timing of a hurricane, tornadoes cover a smaller area and can appear in a matter of minutes. That can give little warning for residents to find appropriate shelter. On Monday, residents of Moore Oklahoma were told that severe weather was coming, but they didn’t get an actual tornado warning until 15 minutes before it hit.
While the tornado in Moore was deadly, it comes in the middle of the tornado season that until now had been relatively quiet.
Warm moist air is a key ingredient in cooking up a tornado. But earlier this year the high altitude winds of the jet stream brought cold air to the Mid West, keeping warmer air out. It’s the same wind pattern that made for a cold in the North East. Now as temperatures continue to rise across the country, there’s no way to know whether the Mid West has seen the worst of extreme weather.