GS1 #Geography #Hurricanes
Hurricane Laura, a Category 4 storm, made landfall in southwestern Louisiana with wind speeds reaching up to 250 km (150 miles) an hour. The US National Hurricane Centre (NHC) warned of “life-threatening conditions”.
What are hurricanes and how do they form?
- Tropical cyclones or hurricanes use warm, moist air as fuel, and therefore form over warm ocean waters near the equator.
- As NASA describes it, when the warm, moist air rises upward from the surface of the ocean, it creates an area of low air pressure below. When this happens, the air from the surrounding areas rushes to fill this place, eventually rising when it becomes warm and moist too.
- When the warm air rises and cools off, the moisture forms clouds. This system of clouds and winds continues to grow and spin, fuelled by the ocean’s heat and the water that evaporates from its surface.
- As such storm systems rotate faster and faster, an eye forms in the centre. Storms that form towards the north of the equator rotate counterclockwise, while those that form to the south spin clockwise because of the rotation of the Earth.
‘Eye’ of the cyclone
- The eye is a region of mostly calm weather at the centre of strong tropical cyclones. The eye of a storm is a roughly circular area, typically 30–65 kilometres (19–40 miles) in diameter. It is surrounded by the eyewall, a ring of towering thunderstorms where the most severe weather and highest winds occur.
- Is there a difference between a hurricane and a tropical storm?
- There is no difference. Depending on where they occur, hurricanes may be called typhoons or cyclones. As per NASA, the scientific name for all these kinds of storms is tropical cyclones.
- The tropical cyclones that form over the Atlantic Ocean or the eastern Pacific Ocean are called hurricanes and the ones that form in the Northwest Pacific are called typhoons. Tropical storms that form in the Bay of Bengal or the Arabian Sea are called cyclones.