What is Hurricane?

In the dictionary, the hurricane means hurricane, storm. Meteorological technicians are translating as 'tropical depression'. But in Answers.com, hurricane hurdles are defined like this: ' It's a big tropical storm, coming from areas along the equator of the Atlantic or the Caribbean or from the eastern Pacific. , often moving north, northwest and northeast from the starting point and always carrying heavy rains, winds of up to 74 miles an hour . '

That is the definition of a typical dictionary. In the encyclopedia dictionary, the hurricane is defined as follows:

'It is a tropical storm that winds over 74 miles / hour (119 km / hour). Wind speed can be up to 190 miles / hour in some cases. People use only hurricane words (tropical low pressure storms for tropical storms in the North Atlantic region). Tropical low pressure storms in the Western Pacific are not called hurricanes, but typhoons (also tropical storms, with strong winds) stemming from the equator. In Australia, tropical low storms are called willy-willy, and if the hurricane is on Indian Ocean, it is called tropical cyclone. Hurricane storms of life can be short or long term, from 1 to 30 days. The storm will weaken and turn into small hurricanes after long-term access to colder seawater at an average distance with the equator. Tropical storms quickly dissipate when landed on land.

Formation of tropical depression (hurricane)

A normal storm reached a tropical low intensity storm (hurricane) that had to go through two intermediate stages of tropical depression and tropical storm. Tropical low pressure storms start from the ocean near the equator, just beginning to gather storms in the tropics. But the low pressure in the center of the storm makes the air moist and when hot from the sea surface makes convection raise the air, the pressure is increasing in the atmosphere that has pushed the air around. The change in the winds makes the clouds tend to revolve around an axis called 'eyes'. If the wind reaches a strong speed, it will turn into a tropical storm. The whirlpool of the wind is getting stronger and the more the cloud is pushed down, the wider it is and when the wind is up to 174 miles / hour, it is called a tropical storm of level 5. Level 5 is the highest level. Tropical typhoon Rita has level 4 with wind power of 145 miles / hour, then when approaching near Port Arthur, it is down to level 3. Images from satellites taken to the surface of the storm show us clearly 'eyes' storm.

Movement speed of tropical low pressure storm

Tropical typhoons often move west at about 10 miles per hour during the initial phase and then round the Earth's polar direction as the storm approaches the western borders of the oceans in longitude 20-30. . In the Northern Hemisphere, small tropical storms often concentrated on the Atlantic Ocean and gradually grew in stature as they began to move toward the West. Tropical low pressure storms are concentrated on the west coast of Mexico and from here move to the Northeast.

Between June and November, on average there are six tropical storms that turn into the annual tropical depression of the North American coast, usually in the Caribbean and the Gulf. Mexico. Two of these storms are heavy storms rated from level 3 to level 5 according to the Saffir-Simpson barometer. For every one of the three typical low-pressure storms moving into the US coast, some other low-pressure storms often change direction from West to Northeast. If we calculate the average, there are about 6 storms of tropical towers that hit the US every year.

Tropical low pressure storms and tropical storms in the North Pacific usually occur between May and December. Tropical storms and hurricanes of the Southern Hemisphere tend to focus from December through April every year. On Bengale Bay and Arabian Sea, tropical cyclones usually occur between April and June or September to December.

Damages caused by tropical low pressure storms

Strong winds are the cause of the first loss of life and property. Another cause of damage is flooding, the result of storms carrying rain like a waterfall. In the case of Hurricane Katrina, the wind is only partially harmful, but the heaviest part is due to the amount of rainwater that is used to block water from Lake Pontchartrain. The measurement with the Saffir-Simpson barometer was chosen as the standard to measure the intensity of the tropical storm.

This measurement is ranked from level 1 (negligible), level 2 (average), level 3 (strong), level 4 (strong), level 5 (disaster). Meanwhile, a super tropical storm is lined up with a large, low-level tropical storm from level 4 to level 5.

According to documents in the archives of the US Department of Meteorology, there have been five tropical low pressure storms that have hit the United States since the day of the Tropical Storm on the 1935 devastating Florida day. Keys, killing 600 people. But the record of damage from the tropical storm has just been destroyed by Hurricane Katrina (until now) with a loss of life of 1,036 people. Here are some tropical storms and cyclones, and the number of lives and material damage is noticeable:

1992 Hurricane Andrew devastated the Homestead, Florida area ( Photo: Noaa )

Hurricane Mitch in 1998, level 5, peak in the Caribbean Sea ( Photo: Nasa )

Hurricane Gilbert in 1988 was a Category 5 typhoon at its peak and the strongest cyclone( Photo: Weathersatellite )

In 1970 tropical cyclones in Bengale Bay killed about 300,000 people, most of them drowned ( Photo: Noaa ).

In the United States, Tropical Storm Hugo 1989 in South Carolina and Opal of Tropical Storm Opal (1995), Cahrley, Ivan and two other storms in 2004 in Florida caused billions of dollars in damage ( Photo: Nasa )

In 2005, Katrina, a peak of level 5 caused flooding in New Orleans.Over 1,000 people in New Orleans die, property losses amount to tens of billions of dollars, maybe even hundreds of billions ( Photo: Firestop.co.za )

In order to lower the level of damage that may be caused by tropical storms, many programs have been studied to block the cause of tropical storms during the developing storm, but the program failed. public. In addition, technicians also study a number of programs to reduce the potential for tropical storms to harm, such as setting up better alarm systems. Special monitoring of tropical low pressure storms must be carried out when storm development conditions start to threaten the people. Responsible agencies need to announce to the public the danger of tropical depression when wind speeds reach up to 74 miles / hour or the sea starts to move strongly, within 24 hours.

Vu Huy Thuc