Tornado observed by BBC film crew
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BBC film crew chase tornado in Colorado

Scientists are getting to grips with the mechanisms behind extreme weather events such as tornadoes.

Dr Helen Czerski visited the US state of Colorado - part of the area known as Tornado Alley - to investigate how tornadoes form with the help of atmospheric scientist Josh Wurman.

No two tornadoes are the same, but they all need certain conditions to form - in particular intense heat.

The final episode of Orbit: Earth's Extraordinary Journey is on BBC2 at 2100 GMT on Sunday 18 March and is available online afterwards on the BBC iPlayer.

  • 18 Mar 2012
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