2. In meteorology, a cyclone is an area of closed,
circular fluid motion rotating in the same
direction as the Earth. This is usually
characterized by inward spiraling winds that
rotate counterclockwise in the Northern
Hemisphere and clockwise in the Southern
Hemisphere of the Earth. Most large-scale
cyclonic circulations are centered on areas of
low atmospheric pressure. The largest low-
pressure systems are cold-core polar cyclones
and extratropical cyclones which lie on the
synoptic scale. According to the National
Hurricane Center glossary, warm-core cyclones
such as tropical cyclones and subtropical
cyclones also lie within the synoptic
scale.Mesocyclones, tornadoes and dust devils
lie within the smaller mesoscale.
3. Formation of cyclones
The main source of energy for tropical cyclones is
the warm oceans in the tropical regions. To initiate
a tropical cyclone the sea-surface temperature
generally needs to be above 26.5°C. However,
existing cyclones often persist as they move over
cooler waters.
The development of a tropical cyclone also relies
on favourable broad-scale wind regimes and can
persist for several days with many following quite
erratic paths. They lose their source of energy
when they move over land or colder oceans causing
them to dissipate. Weakening may also occur if the
cyclone moves into an unfavourable wind regime
which disrupts the structure of the system.
Sometimes a decaying tropical cyclone may
interact with a weather system in higher latitudes
to cause impacts far from the tropics.
4. The main effects of cyclones include
heavy rain, strong wind, large storm
surges at landfall, and tornadoes. The
destruction from a cyclone depends
mainly on its intensity, its size, and its
location. cyclones act to remove forest
canopy as well as change the landscape
near coastal areas, by moving and
reshaping sand dunes and causing
extensive erosion along the coast. Even
well inland, heavy rainfall can lead to
mudslides and landslides in mountainous
areas. Their effects can be sensed over
time by studying the concentration of the
Oxygen-18 isotope within caves within
the vicinity of cyclones' paths.
5. A storm is any disturbed state of an environment or
astronomical body's atmosphere especially affecting its
surface, and strongly implying severe weather. It may be
marked by significant disruptions to normal conditions such
as strong wind, hail, thunder and lightning (a thunderstorm),
heavy precipitation (snowstorm, rainstorm), heavy freezing
rain (ice storm), strong winds (tropical cyclone, windstorm),
or wind transporting some substance through the
atmosphere as in a dust storm, blizzard, sandstorm, etc.
Storms generally lead to negative impacts on lives and
property such as storm surge, heavy rain or snow (causing
flooding or road impassibility), lightning, wildfires, and
vertical wind shear; however, systems with significant rainfall
can alleviate drought in places they move through. Heavy
snowfall can allow special recreational activities to take place
which would not be possible otherwise, such as skiing and
snowmobiling.
6. A tornado is a violently rotating column of air that is in
contact with both the surface of the earth and a
cumulonimbus cloud or, in rare cases, the base of a
cumulus cloud. They are often referred to as twisters or
cyclones, although the word cyclone is used in
meteorology, in a wider sense, to name any closed low
pressure circulation. Tornadoes come in many shapes
and sizes, but they are typically in the form of a visible
condensation funnel, whose narrow end touches the
earth and is often encircled by a cloud of debris and
dust. Most tornadoes have wind speeds less than 110
miles per hour (180 km/h), are about 250 feet (80 m)
across, and travel a few miles (several kilometers) before
dissipating. The most extreme tornadoes can attain wind
speeds of more than 300 miles per hour (480 km/h),
stretch more than two miles (3 km) across, and stay on
the ground for dozens of miles (more than 100 km)
7. As the mesocyclone lowers below the cloud
base, it begins to take in cool, moist air from the
downdraft region of the storm. This
convergence of warm air in the updraft, and this
cool air, causes a rotating wall cloud to form.
The RFD also focuses the mesocyclone's base,
causing it to siphon air from a smaller and
smaller area on the ground. As the updraft
intensifies, it creates an area of low pressure at
the surface. This pulls the focused mesocyclone
down, in the form of a visible condensation
funnel. As the funnel descends, the RFD also
reaches the ground, creating a gust front that
can cause severe damage a good distance from
the tornado. Usually, the funnel cloud begins
causing damage on the ground (becoming a
tornado) within a few minutes of the RFD
reaching the ground.
8. Tornadoes effect the environment by destroying buildings
and trees. Tornadoes also kill animals, which effects the
food chain and disrupts the whole environment. Tornadoes
destroy our farms, which means there will be food
shortages around the surrounding area. After everything is
destroyed, humans have to rebuild. Tornadoes can cause
water contamination, which poses a serious problem, as
plants, animals and humans are effected by this. Debris
can be very dangerous, as it could kill plants and animals
very easily. Some trees take over 100 years to grow, so if
they are destroyed, they will be hard to replace. Fires may
occur after a tornado due to damaged power lines and gas
leaks. Fire contributes to global warming by giving off
carbon dioxide into the atmosphere. Because of man-made
global warming, scientists believe that there will be an
increases in tornadoes and other severe weather
9. Average speed
The average speed of a cyclone
is 200-280 kmph
The average speed of a tornado
is 48-112 kmph
The highest speed of cyclone
ever recorded was 408 kmph
The highest speed of tornado
ever recorded was 511 kmph
10. The 1999 Odisha cyclone, also known as Cyclone
05B, and Paradip cyclone,[1] was the strongest
tropical cyclone ever recorded in the North
Indian Ocean. It was also the deadliest tropical
cyclone in the Indian Ocean since the 1991
Bangladesh cyclone, and deadliest Indian storm
since 1971. The Category 5 storm made landfall
just weeks after a Category 4 storm hit the same
general area. It was a tropical depression formed
over the Malay Peninsula on October 25. It
moved to the northwest and became a tropical
storm on October 26. It continued to strengthen
into a cyclone on October 27. On October 28, it
became a severe cyclone with a peak of 160
mph (260 km/h) winds. It hit India the next day
as a 155 mph (250 km/h) cyclone. It caused the
deaths of about 10,000 people, and heavy to
extreme damage in its path of destruction.
