A.
What is super typhoon?
v A violent storm originating over tropical or subtropical
waters, characterized by violent rainstorms and high-velocity cyclonic winds.
v "Super-typhoon" is a term utilized by the U.S. Joint Typhoon Warning
Center for typhoons that reach maximum sustained 1-minute surface winds of at least 65 m/s (130 kt, 150 mph). This is the
equivalent of a strong Saffir-Simpson
category 4 or category 5 hurricanes in the Atlantic basin or a category 5 severe tropical
cyclone in the Australian basin.
v Super typhoons are
very strong tropical cyclones. While the
difference between a hurricane and typhoon are simply a matter of location, a super typhoon is
best compared to a major hurricane of a Category 4 or 5 on the Saffir-Simpson Scale. In other
words, a super typhoon is simply a very strong typhoon.
B.
How are they formed?
typhoons
are enormous heat engines that generate energy on a staggering scale. They draw
heat from warm, moist ocean air and release it through condensation of water
vapor in thunderstorms.
typhoons
spin around a low-pressure center known as the “eye.” Sinking air makes this
20- to 30-mile-wide (32- to 48-kilometer-wide) area notoriously calm. But the
eye is surrounded by a circular “eye wall” that hosts the storm’s strongest
winds and rain.
These
storms bring destruction ashore in many different ways. When a hurricane makes
landfall it often produces a devastating storm surge that can reach 20 feet (6
meters) high and extend nearly 100 miles (161 kilometers). Ninety percent of
all hurricane deaths result from storm surges.
A
typhoon’s high winds are also destructive and may spawn tornadoes. Torrential
rains cause further damage by spawning floods and landslides, which may occur
many miles inland.
Typhoons are fuelled by warm seawater evaporating and rising
before condensing into clouds and rain when it meets cooler air. The earth's rotation
makes the cyclone spin rapidly, clockwise in the southern hemisphere and
anticlockwise north of the equator. If a cyclone is strong enough, air sinks
rather than rises at the centre, causing the famous "eye" - an area
of calm that can stretch for hundreds of miles in diameter in the biggest
storms. The "eye wall" surrounding it brings the strongest wind and
heaviest rain.
C.
How destructive are they?
v Once the typhoons get to 74 miles per hour it can be classified as a hurricane
or a monsoon. When typhoon sustained winds of 195 mph, the wind drove a massive
storm surge onto land. The combined extreme wind and raging floods were too.
Much for most buildings to withstand. Yes, typhoons and Hurricanes can tear
roof of buildings and worst.
D.
What is the reminder/preparation in case of super typhoon?
Plan Ahead
1. Determine whether
you can remain in your home during the typhoon. You may be able to ride out a
weak typhoon with a small storm surge but will need to evacuate for stronger
storms. Listen for warnings from your local officials or weather personnel in
situations where evacuation is ordered. Note the evacuation routes and plan to
leave early.
2. Make lists
of television and radio stations where you can get storm information, phone
numbers to call in case of emergencies and locations of storm shelters. Get
directions for the emergency shelters.
3. Designate a location for you and your family members to meet if you
get separated and the number of an out-of-state relative to call to say
everyone is safe. That out-of-state person starts the phone tree to others on
your list after learning you are okay.
4. Find a place to take your pets where they will be safe if you have to
evacuate. Most storm shelters won't allow pets.
5. Remember to shut off electricity, water and gas to your home before
evacuating.
Assemble
a Typhoon Kit
6. Pack food that doesn't have to be refrigerated or cooked along with
disposable plates, bowls, forks, knives and spoons. Each person and pet in the
home should have enough to eat for three days.
7. Store water. Each person needs three gallons of clean water to drink
and to use for washing. Pets also need water.
8. Add flashlights, oil lamps, lanterns and candles, along with extra
batteries, matches and fuel.
9. Include a first aid kit in your typhoon kit.
10. Remember to pack board games, card decks and a battery-operated
radio.
11. Throw in a box of garbage bags and paper towels.
Pack
Your Bags
12. Pack a small bag or backpack for each person in the home. It should
include clothes and toiletries for three days.
13. Bundle a blanket and pillow for each person and place them in
garbage bags (to keep them dry) to take along if evacuating.
14. Include a small bag of photos and documents you can't afford to have
destroyed, such as wills and wedding albums.
15. Place everyone's bag and bed bundle near the door so they can be
quickly loaded into the car if you decide to evacuate. Fill the car with gas.
E.
What are the effects of a super typhoon?
v Storm surge and tidal flooding
ð This is
the most devastating and notable effect from a hurricane. Storm surge is the rising
wall of water comes ashore with a land falling hurricane, and is responsible for
90 percent of all hurricane related deaths.
ð A storm surge is an offshore rise of water
associated with a low pressure weather system, typically tropical
cyclones and strong extra tropical
cyclones. Storm surges are caused primarily by high winds pushing on the ocean's surface. The wind causes the water to pile up
higher than the ordinary sea level. Low pressure at the centre of a weather system
also has a small secondary effect, as can the bathymetry of the body of water. It is
this combined effect of low pressure and persistent wind over a shallow water
body which is the most common cause of storm surge flooding problems. The term
"storm surge" in casual (non-scientific) use is storm
tide; that is, it refers to the rise of water
associated with the storm, plus tide, wave run-up, and freshwater flooding.
"Tidal surge" is incorrect since there is no such thing. When
referring to storm surge height, it is important to clarify the usage, as well
as the reference point.
v High Wind
ð This is the
most important effect of a hurricane since it determines how powerful the storm
is, and how much storm surge and damage it can cause. Winds in a hurricane can reach
up to 200 mph.
ð a very strong wind; "rain and high winds covered the region"
air current, current of air, wind - air moving (sometimes with
considerable force) from an area of high pressure to an area of low pressure;
"trees bent under the fierce winds"; "when there is no wind,
row"; "the radioactivity was being swept upwards by the air current
and out into the atmosphere"
v Tornadoes
ð This is probably
the least thought of effect of a hurricane, but they do occur. Tornadoes occur
in a hurricane as a result of the tremendous energy and instability created
when a hurricane makes landfall. Most tornadoes that occur in hurricanes are
only minimal in strength.
ð 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,[1] 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 (177 km/h), are about 250 feet (76 m) across, and
travel a few miles (several kilometers) before dissipating.
v Heavy rain and flooding
ð This is
the effect of a hurricane that is completely taken for granted. After hurricanes
make landfall, and their winds abate, the tremendous amounts of rainfall become
a major factor, and can cause significant flooding as with typhoon Haiyan (Yolanda).
ð A flood is an overflow of water that
submerges land which is usually dry.
F.
What is your reaction to the devastation caused by super
typhoon Yolanda?
Typhoon Haiyan, known as Typhoon Yolanda in the Philippines, was an exceptionally powerful tropical cyclone that devastated portions of Southeast Asia, particularly the Philippines, in early November 2013. It is the deadliest Philippine typhoon on record, killing at least 6,183 people in that country alone. Haiyan is also the strongest storm recorded at landfall, and unofficially the strongest typhoon ever recorded in terms of wind speed.
The thirtieth named storm of the 2013 Pacific typhoon season, Haiyan originated from an area of low pressure several hundred kilometers east-southeast of Pohnpei in the Federated States of Micronesia on November 2, 2013. Tracking generally westward, environmental conditions favored tropical cyclogenesis and the system developed into a tropical depression the following day. After becoming a tropical storm and attaining the name Haiyan at 0000 UTC on November 4, the system began a period of rapid intensification that brought it to typhoon intensity by 1800 UTC on November 5. By November 6, the Joint Typhoon Warning Centre(JTWC) assessed the system as a Category 5-equivalent super typhoon on the Saffir-Simpson hurricane wind scale; the storm passed over the island of Kayangel in Palau shortly after attaining this strength.
Thereafter, it continued to intensify; at 1200 UTC on November 7, the Japan Meteorological Agency (JMA) upgraded the storm's maximum ten-minute sustained winds to 235 km/h (145 mph), the highest in relation to the cyclone. The Hong Kong Observatory put the storm's maximum ten-minute sustained winds at 275 km/h (170 mph) prior to landfall in the central Philippines, while the China Meteorological Administration estimated the maximum ten-minute sustained winds at the time to be around 75 m/s (270 km/h or 167 mph). At 1800 UTC, the JTWC estimated the system's one-minute sustained winds to 315 km/h (196 mph), unofficially making Haiyan the strongest tropical cyclone ever observed based on wind speed; several others have recorded lower central pressure readings. Several hours later, the eye of the cyclone made its first landfall in the Philippines at Guiuan, Eastern Samar. With little change in intensity at landfall, this would make Haiyan the strongest tropical cyclone at landfall on record based on wind speed, surpassing the old record of 305 km/h (190 mph) set by Atlantic Hurricane Camille in 1969. Gradually weakening, the storm made five additional landfalls in the country before emerging over the South China Sea. Turning northwestward, the typhoon eventually struck northern Vietnam as a severe tropical storm on November 10. Haiyan was last noted as a tropical depression by the JMA the following day.
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