Processes causing the formation and development of cyclones, hurricanes, typhoons and tornadoes. Flashcards
What are cyclones, hurricanes, and typhoons?
They are intense low-pressure systems with strong winds and heavy rainfall, differing only in their location
Where do cyclones happen
Indian Ocean and South Pacific
Where do Hurricanes happen
Atlantic and Eastern Pacific
Where do Typhoons happen
Western Pacific.
What is the primary energy source for tropical cyclones, hurricanes, and typhoons?
Warm ocean water (at least 27°C ), which provides heat and moisture to fuel the storm.
What 5 atmospheric conditions are needed for cyclones, hurricanes, or typhoons to form?
- Warm ocean water
- Low wind shear
- High humidity in the lower to middle atmosphere
- Pre-existing weather disturbance
- Coriolis effect to initiate rotation.
What is the Coriolis effect, and how does it relate to cyclones?
The Coriolis effect is the deflection of moving air due to Earth’s rotation, causing cyclones to spin counterclockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere.
What triggers the formation of tornadoes?
Tornadoes form when warm, moist air meets cold, dry air, creating instability and wind shear in the atmosphere, often during severe thunderstorms.
What is wind shear, and why is it important for tornado formation?
Wind shear is a change in wind speed or direction with height. It causes horizontal rotation in the atmosphere, which can tilt vertically to form a tornado.
What is the role of the eye in a tropical cyclone?
The eye is the calm center of a cyclone, surrounded by the eye wall, where the most intense winds and rain occur.
What factors can weaken a cyclone, hurricane, or typhoon?
Moving over cooler waters, land, or encountering strong wind shear, which disrupts the storm’s structure.
How do supercell thunderstorms relate to tornadoes?
Tornadoes often form from supercell thunderstorms, which have a rotating updraft (mesocyclone) created by wind shear.
What is the Enhanced Fujita (EF) Scale?
A scale that measures tornado intensity based on damage, ranging from EF0 (weakest) to EF5 (most severe).
How are hurricanes categorized?
Using the Saffir-Simpson Hurricane Wind Scale, from Category 1 (74-95 mph winds) to Category 5 (157+ mph winds).
What is a tornado outbreak?
A series of tornadoes spawned by the same weather system in a short period, often over a large area.
