Tornado

What is tornado and water spouts

Characteristic

World tornado affecting zone in map

How its form

Classification

Why tornadoes are so destructive

Effect

Recent tornadoes

Is derived from Spanish

word “TORNADO” whichcomes from “tronar” which

means “to thunder”

Tornadoes are funnel

shaped storms where in the

upper portion is like anumbrella in shape while

lower portion is like pipe

which touches the surface

According to “the national

oceanic and atmosphericadministration”-a tornado is

violently rotating column of

air along the ground Fig: Tornado

A water spout is less

intense and causes far less damage. It

forms over warm

tropical ocean

waters although its funnel is made of

fresh water

Fig : water spouts

Most violence of all the storms.

It moves with average speed of 40-60km

Follow very narrow path

Average duration is 15-20min

At this point in time, formation of tornadoes are not fully

understood by scientists. They usually form in a giant rotatingthunderstorm called a super cell

A squall line, or narrow zone of cumulonimbus clouds forms,

giving life to the tornadoes. Lightning flashes, and heavy rains

and hail begin to fall

Soon after, the easiest recognizable part of the tornado, the

funnel, seems to descend from the base of the cloud

the pressure within the cloud drops due to the increasing

wind speeds

As the pressure drops, it causes moisture in the air tocondense. This action continues down the spiral, giving the

impression that the funnel is descending from the cloud base.

It touches the ground surface and tornado is formed.

CLASS(SCALE) FUJITA WIND SPEEDPEARSON PATH

LENGTH

PEARSON PATH

WIDTH

- 0 to 40 mph less than 0.3 miles Less than 6 yards

0 40 to 72 mph 0.3 to 0.9 miles 6 to 17 yards

1 73 to 112 mph 1.0 to 3.1 miles 18 to 55 yards

2 113 to 157 mph 3.2 to 9.9 miles 56 to 175

3 158 to 206 mph 10 to 31 miles 176 to 566 yards

4 207 to 260 mph 32 to 99 miles 0.3 to 0.9 miles

5 261 to 318 mph 100 to 315 miles 1.0 to 3.1 miles

Sudden decrease of air pressure.

Air is rotated very rapidly.

The power of rising

Ecological balance

may be hampered

Destroys everything

on its way

Heavy loss of human

and animal life

Burst out the building

Damage of

communication

Rank Name(location) Country Date Death

1 Daultipur and Salturia

Bangladesh26th april,1989 1300

21969 East Pakistan Tornado

East Pakistan ,Pakistan (now Bangladesh)

14th april,1969 923

3 Tri-State US 18th march1925 695

4Manikganj, Singair and Nawabganj

Bangladesh 17th april,1973 681

5Magura and Narail Districts

Bangladesh 11th march,1964 500

6Madaripur and Shibchar

Bangladesh 1st april,1977 500

7Belyanitsky, Ivanovo and Balino

Russia 9th june,1984 400

8North of Cooch Behar and surrounding area

India,Bangladesh

19th april,1963 300

9Bhakua and Haripur unions

Bangladesh 29th april,1972 300

NATIONAL GEOGRAPHY

WIKIPEDIA

CLIMATOLOGY-Savindra singh

JOLOBAIU BIDDA-Arif & Kabir