Thursday 26 February 2009

Final Documentary

In my Final Documentary animation i choose to focus on what a tornado is, the life cycle the tornado follows, the scale of tornadoes and how they are catagorised and the systems in place to help predict a tornado. the animation is accomapnied by a voice over supplied by Thomas Landman, ambient background sounds of a tornado and short clips of actual footage from tornadoes. i believe that my combination of diagrams, tornado footage and tornado replicas work well together. Although there were some problems involoving rendering times and few substutes had to made to finish in time for the deadline, i think these have been well thought out and place.

i think there is only one issue with the formation of tornadoes scenes, with dust that is a little 'glitchy'. however after showing to a small audience at home, they notice and thought that it was apart of the way the tornado ran.

Sunday 8 February 2009

Searching for the Sound

Tornadoes have been described as sounding like a freight train hurtleing down a track as they both contain a loud roar within their sound spectrum, however a sound of a tornado can be affected by the debris of which it contains.

Friday 6 February 2009

Script Draft

Opening sequence
Black background with a faint tornado animation in centre of screen. Actor/Speaker sits to the right of the screen on a tall stall, greeting viewers and areas that will be covered in the programme. As the actor describes the subjects to be covered, stills to describe the scenes appear as a college to the left of the screen.

Speaker
Hello and welcome. Today we will be talking about Tornadoes. We will uncover the true definitions for what a tornado is, along with its variations from water spouts to fire whirls. Using the science of meteorology and weather conditions, we will discover how tornadoes form and its life cycle. We will also take a look into the weather conditions needed to create tornadoes and the weather systems used to predict tornadoes and we will find out where the most are commonly and worst affected areas for tornadoes.

FADE TO BLACK and CUT TO:

“What is a tornado?”
Title page appears, fading in from black. Fade title to animation of a tornado developing and running across the country side.

Speaker
The Glossary of Meteorology defines a tornado as a “violently rotating column of air, which is in contact with the ground,” this spinning funnel of wind called a vortex. The name tornado derives from the Spanish word for thunderstorms, “Tronada.” A tornado can also commonly known as a twister.

FADE TO BLACK and CUT TO:

Tornadoes Life Cycle
Fade title from black. Supercell above as seen by meteorologists from radar screens, animate the storm cycle, animation of warm and cool air streams colliding on the ground, and swirling into each other pointing upwards. Fall of cool air behind the forming tornado, RDF.

Speaker
Tornadoes happen when warm and cool airstream's collide, creating a rotating area of low atmospheric pressure. There are a few stages in the development of tornadoes which are consistent, with a few exceptions. The first stage of a tornado forms from a tornadic thunderstorm, which has grown in intensity to a supercell. The supercell contains a concentrated area of rotation low in the atmosphere, this rotation causes the development of tornadoes. While this occurs in the sky above, the wind direction on the ground changes and increases beginning to swirl, the spinning in the lower atmosphere increases changes the height and angle from horizontal to vertical. The supercells within a thunderstorm begin tornadoes with an area of rapidly descending air follow known as Rear Flank Downdraft, also known as RFD. This RFD accelerates in its decent dragging the rotation in the atmosphere with it, thus creating the start of a Tornado.
Formation - vortex funnel extends down from the supercell, very thick large cloud, still rotating. Large, thick rotation of cloud slowly thinning out on the way down.
The second stage in the tornadoes life cycle sees the formation. As the rotation of the cyclone approaches the ground, a funnel of cloud appears to descend from the base of the storm, often from a rotating wall cloud. As the funnel descends, the RFD also reaches the ground, creating a gust front that can cause damage a good distance from the tornado. Usually, the funnel cloud becomes a tornado within minutes of the RFD reaching the ground. Wind speeds increase and the area of rotation extends through much of the storm. Most strong and violent tornadoes form within this area of strong rotation.
Maturity – Rotating cloud extends to ground, creating dust flow around the funnel. Rotation from the clouds meets rising rotation from the ground.
The third stage of the life cycle is the mature stage, the stage in which the tornado will cause most of the damage. From the start of its life cycle the tornado has a good source of warm moist air from the lower atmosphere. The mature stage of the tornado is in constant growth, this stage can last anywhere from a few minutes to a few hours while travelling many miles. In rare cases the tornado itself can be more than a mile across. During this stage the RDF becomes a cool surface of which wrap around the tornado cutting off the warm moist air which feeds it. This stage is often nearly rain-free, this is because the moisture in the air becomes caught in the rotating winds. The rain often falls behind the rotating winds. Often within the tornadic thunderstorm hail stones the size of tennis balls cause as much damage as the winds speeds
Dimise – tornado slows and fades.
The last stage of a tornadoes life cycle is its demise. As t he RDF chocks off the warm air supply the vortex begins to weaken and thin. This stage often lasts no more then a few minutes, as the tornado fizzles to dust. At this stage the shape of the Tornado is determined by the wind from the storm, the tornado could morph into a dizzy array of frantic patterns. Even though the tornado is dying at this stage, it is still capable of causing damage and destruction. As the tornado thins, the wind speeds increase, sometimes causing new intense supercells to develop, producing a new tornado.

FADE TO BLACK and CUT TO:

“F Force. Tornadoes”
Fade title from black. Live images of tornados.

Speaker
In the early stages of discovering and understanding the science of tornados, scientists did not have the technology to determine specific details such as wind speed, this was due to the fact they could not get closer enough safely to take accurate measurements manually. However scientist and meteorologist Ted Fujita of the University of Chicago in 1971 developed a scale which could decipher the size and intensity of a tornado by the devastation left in its wake. However the prediction of the size of a tornado would not be possible as it relays on the aftermath of a tornadic storm. Even with this scale, the grading of a tornado come from the best educated guess, as there are no allowances for strength of constructions or damage from other elements. In order to get an accurate scale, Fujita discovered that wind speed was needed. During his research and development of the scale, Fujita discovered that tornado wind speeds required to inflict the damage were much lower, particularly in the higher categories

Animation showing the different strengths of tornado
Speaker
F1 Tornado - wind speeds between 73-112mph. Even the smallest tornadoes can peel slates from roofs and drive moving cars off the road.
F2 Tornado - wind speeds between 113-157mph. Roofs of some houses will begin to lift off and mobile homes in the tornado’s path would be demolished.
F3 Tornado - wind speeds between 158-207mph. Heavy trees will be uprooted and walls and roofs of solid buildings will be torn away like matchsticks.
F4 Tornado - wind speeds between 208-260mph. Locomotive engines and 40 tonne articulated trucks will be flung around like toys.
F5 Tornado - wind speeds between 261-318mph. Cars are flung like stones for hundreds of metres and entire buildings can be ripped from the ground. The force is similar to that of an atomic bomb.

FADE TO BLACK and CUT TO:

Locations
Fade title from black. Rotating planet Earth with tornadoes on each continent, to represent the amount and location. Zoom in to continent of USA, colour coordinate for Tornado Alley with animation of air flows to explain the weather patterns.

Speaker
Tornadoes happen across all continents, but one, the Antarctic. Of all the continents which are affected by tornadoes, the United States of America are affected worst of all. America contains about 80% of the tornadoes from across the planet, however within the United States one area is affected more than others, Tornado Alley. Tornado Alley lies in the flattest planes across the central states, ranging from the North Dakota down to main land Texas and Louisiana, stretching across from the East of Colorado and Wyoming to Ohio, Kentucky and Tennessee. Tornado Alley has perfect weather patterns for the formation of tornadoes, with the collisions of the cold, dry arctic atmospheric conditions from the North and warm, moist tropical atmospheric conditions from the south.

An Idea Update

This piece is about the life cycle of a tornado and the way in which people coupe or what they should do. The animation is aimed at the general public, and is to be screened on the discovery channel. from my research i have found that their are very few programmes about tornadoes, however there are two distinct styles for tornado documentrays. The first is a factual piece with a commentator talking to the auidience about what is happening on screen and interviewing scientist that follow tornadoes. The other style is now of a reality TV piece, folloing the life of a storm chaser.

My piece will follow the style of a scientist giving out factual information about tornadoes, how there formed, where they are most common and the prediction system, with hints and tips on what signs people should look for.

Sunday 1 February 2009

Fujita Scale

The Fujita scale was created by Ted Fujita of the University of Chicago developed a scale, along with the help and expertise of Allen Pearson, in 1971 in order the rate the size of a tornado. The scale was developed in accordance to the damage left behind. This meant that even in a prediction of a tornado, the size of the tornado could not be specified until the aftermath had been assessed, therefore Fujita Scale can only be used as a best educated guess, however it was a start for tornado research. Fujita and other scientists recognised early on that, in order to get an accurate reading for scale to compare the size and intensity of a tornado, wind speeds are needed to be recorded accurately. With subsequent research, Fujita discovered that tornado wind speeds required to inflict the damage, he'd previously described in the scale, were much lower, particularly in the higher categories. others factors which left Fujita's scale as a best guess was due to the little leeway given of the strength of the construction or other elements which could have caused the damage. In 1992 Fujita tried to modify and update the scale but by then he was semi-retired and the National Weather Service was not in a position for the undertaking of updating to an entirely new scale.

Saturday 31 January 2009

Tornado Alley

Tornado Alley is located in the mid and Eastern states of the USA. Tornado Alley is the most common area for tornadoes the United States due to the warm, moist air from the tropical south meeting the cold dry Arctic air from the north. the area stretches from West-Texas to North-Dakota. It is 1600 kilometres from north to south and 950 kilometres from east to west. Tornado alley's large and flat area of land, combined with the collision of air currents from the north and south create the perfect conditions for tornadic thunderstorms.

Friday 30 January 2009

Tornado Life Cycle

Supercell
Tornadoes often develop from a class of thunderstorms known as supercells. Supercells contain a concentrated area of rotation low in the atmosphere, this rotation causes the development of tornadoes. Tornadoes that form from the supercell often follow the same life cycle. The supercells within a thunderstorm begin tornadoes with an area of rapidly descending air follow known as Rear Flank Downdraft (RFD). This RFD accelerates in its decent dragging the rotation in the atmosphere with it, thus creating the start of a Tornado.

Formation
As the rotation of the cyclone approaches the ground, a visible condensation funnel appears to descend from the base of the storm, often from a rotating wall cloud. As the funnel descends, the RFD also reaches the ground, creating a gust front that can cause damage a good distance from the tornado. Usually, the funnel cloud becomes a tornado within minutes of the RFD reaching the ground

Maturity
From the start the tornado has a good source of warm, moist atmosphere to power it, so that it can grow to its mature stage. This can last anywhere from a few minutes to more than an hour. During its mature stage the tornado often causes the most damage. In rare cases the Tornado can be more than one mile across. During the mature stage the RFD becomes a cool surface of winds and begins to wrap around the tornado, cutting off the warm air which feeds the it.

Dismise
As the RFD surrounds and chokes off the tornado's air supply, the vortex begins to weaken, and becomes thin. This stage often lasting no more than a few minutes, after which the tornado fizzles. The shape of the tornado is now determined by the winds of the storm above and can be blown into fantastic patterns. Even though the tornado is dieing, the tornado is still capable of causing damage. The storm is contracting into a thin tube and winds can increase. intense supercells tornadoes can develop cyclically. As the first tornado dissipate, the storm's inflow may be concentrated into a new area closer to the center of the storm. If a new cyclone develops, the cycle could start all over again, producing new tornadoes. Occasionally, the first and second cyclone produce a tornado at the same time.

Though this is a widely-accepted theory for how most tornadoes form, live, and die, it does not explain the formation of smaller tornadoes, such as land spouts, long-lived tornadoes, or tornadoes with multiple vortexes, however, most tornadoes follow a pattern similar to this one.