Hurricane, Cyclone and Typhoon

By

 A tropical cyclone is a rapid rotating storm originating over tropical oceans from where it draws the energy to develop. It has a low pressure centre and clouds spiraling towards the eyewall surrounding the "eye", the central part of the system where the weather is normally calm and free of clouds. Its diameter is typically around 200 to 500 km, but can reach 1000 km. A tropical cyclone brings very violent winds, torrential rain, high waves and, in some cases, very destructive storm surges and coastal flooding. The winds blow counterclockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere. Tropical cyclones above a certain strength are given names in the interests of public safety.

 Hurricane, cyclone and typhoon are different terms for the same weather phenomenon: torrential rain and maximum sustained wind speeds (near centre) exceeding 119 kilometers per hour:

  • In the western North Atlantic, central and eastern North Pacific, Caribbean Sea and Gulf of Mexico, such a weather phenomenon is called "hurricanes".
  • In the western North Pacific, it is called "typhoons"
  • In the Bay of Bengal and Arabian Sea, it is called "cyclones"
  • In western South Pacific and southeast India Ocean, it is called “severe tropical cyclones”
  •  In the southwest India Ocean, it is called “tropical cyclones”

The typhoon season in the western North Pacific region typically runs from May to November. The Americas/Caribbean hurricane season runs from June 1 to November 30, peaking in August and September. The cyclone season in South Pacific and Australia normally runs from November to April. In the Bay of Bengal and Arabian Sea, tropical cyclones usually occur from April to June, and September to November. The East Coast of Africa normally experiences tropical cyclones from November to April.

 Depending on the maximum sustained wind speed, tropical cyclones will be designated as follows:

  • It is a tropical depression when the maximum sustained wind speed is less than 63 km/h.
  • It is a tropical storm when the maximum sustained wind speed is more than 63 km/h. It is then also given a name.
  • Depending on the ocean basins, it is designated either a hurricane, typhoon, severe tropical cyclone, severe cyclonic storm or tropical cyclone when the maximum sustained wind speed is more than 119 km/h.

Tropical cyclones can be hundreds of kilometers wide and can bring destructive high winds, torrential rain, storm surge and occasionally tornadoes. According to the Saffir-Simpson Hurricane Wind Scale, the hurricane strength varies from Category 1 to 5:

  • Category 1 hurricane is referring to the hurricane with maximum sustained wind speeds of 119-153 km/h.
  • Category 2 hurricane is referring to the hurricane with maximum sustained wind speeds of 154-177 km/h.
  • Category 3 hurricane is referring to the hurricane with maximum sustained wind speeds of 178-209 km/h.
  • Category 4 hurricane is referring to the hurricane with  maximum sustained wind speeds of 210-249 km/h.
  • Category 5 hurricane is referring to the hurricane with maximum sustained wind speeds exceeding 249 km/h.

The impact of a tropical cyclone and the expected damage depend not just on wind speed, but also on factors such as the moving speed, duration of strong wind and accumulated rainfall during and after landfall, sudden change of moving direction and intensity, the structure (e.g. size and intensity) of the tropical cyclone, as well as human response to tropical cyclone disasters.

https://public.wmo.int/en/our-mandate/focus-areas/natural-hazards-and-disaster-risk-reduction

https://public.wmo.int/en/node/8447/tropical-cyclone-naming%29

https://public.wmo.int/en/our-mandate/focus-areas/natural-hazards-and-disaster-risk-reduction/tropical-cyclones

https://www.nhc.noaa.gov/aboutsshws.php

Comments

Post a Comment

Popular posts from this blog

Russian parliament passed a bill to revoke its ratification of the Comprehensive Test Ban Treaty

By
Relevance:  Russia revokes ratification of nuclear test ban treaty (CTBT) - ICAN But it affirmed that it will  retain its cooperation with the treaty’s verification system and implementing organisation.  Comprehensive Test Ban Treaty: The Comprehensive Test Ban Treaty (CTBT), which opened for signature in 1996, was intended to prohibit all nuclear weapon test explosions. Over 2,000 nuclear tests occurred between 1945 and 1996: the United States (1,000+), the Soviet Union (700+), France (200+), the United Kingdom and China (45 each). As at January 2013, 183 countries had signed the Treaty, of which 158 have also ratified it, including three of the nuclear weapon states (France, the Russian Federation and the United Kingdom). However, 44 specific nuclear technology holder countries must sign and ratify before the CTBT can enter into force. Of these, eight are still missing: China, Egypt, India , Iran, Israel, North Korea, Pakistan and the US. India , North Korea and Pakista...
Read more

Interstellar space and Interstellar Probes ( Voyager and New Horizons Missions )

By
Interstellar Space: Interstellar space is often called the space between the stars, but more specifically, it’s the region between our Sun’s heliosphere and the astrospheres of other stars. Our heliosphere is a vast bubble of plasma – a gas of charged particles – that spews out of the Sun. This outflow is known as the solar wind. The bubble surrounds the Sun and stretches beyond the planets. Both Voyager spacecraft had to travel more than 11 billion miles (17 billion kilometers) from the Sun in order to cross the edge of the heliosphere. This bubble is moving through interstellar space as the Sun orbits the center of the Milky Way galaxy. As our heliosphere plows through space, it creates a bow wave, like the wave formed by the bow of a ship. Kuiper Belt &  Oort Cloud: The Kuiper Belt is a doughnut-shaped ring of icy objects around the Sun, extending just beyond the orbit of Neptune from about 30 to 55 AU. Similar to the asteroid belt, the Kuiper Belt is a region of leftovers f...
Read more

ISRO developing semi-cryogenic engine working on LOX Kerosene propellant

By
ISRO is developing a 2000 kN thrust semi-cryogenic engine working on an LOX Kerosene propellant combination for enhancing the payload capability of LVM3 and for future launch vehicles. Liquid Propulsion Systems Centre (LPSC) is the lead centre for the development of semi-cryogenic propulsion systems with the support of other launch vehicle centres of ISRO. The assembly and testing of the propulsion modules were done at the ISRO propulsion complex (IPRC), Mahendragiri. As part of the engine development, a pre-burner ignition test article, which is a full complement of the engine power head system excluding the turbopumps is realized. The first ignition trial was conducted successfully on May 2, 2024, at semi cryo integrated engine test facility (SIET) at IPRC, Mahendragiri, which was dedicated to the nation recently by the honorable Prime Minister of India. Smooth and sustained ignition of the preburner is demonstrated which is vital for the starting of the semi-cryogenic engine. Semi-c...
Read more