Convective Cyclogenesis (Development of Tropical Cyclones) Flashcards
What is convective cyclogenesis?
The process of tropical cyclone formation, starting from a disturbance to a full-fledged cyclone.
What are the three types of cyclogenesis?
Convective cyclogenesis (tropical cyclones), frontal cyclogenesis (extratropical cyclones), and mesocyclones (tornadoes & waterspouts).
What is the first stage of convective cyclogenesis?
Tropical Disturbance – A weak, low-pressure system with clusters of thunderstorms.
What is a tropical depression?
A low-pressure system with sustained winds below 63 km/h, often the second stage of cyclogenesis.
What is a tropical storm?
A system with sustained winds 63–119 km/h, more organized than a depression but without a well-formed eye.
What marks the transition from a tropical storm to a tropical cyclone?
When sustained wind speeds exceed 119 km/h, and an eye begins to develop.
What is the inflow layer of a tropical cyclone?
The lowest layer (up to 3 km altitude) where warm, moist air is drawn in.
What is the outflow layer in a tropical cyclone?
The upper layer (above 7 km), where air spreads outward, allowing the system to intensify.
How does condensation contribute to cyclone development?
Condensation releases latent heat, which warms the air and strengthens convection.
What is the role of the Coriolis force in cyclogenesis?
It causes the system to rotate, forming a cyclonic vortex.
At what latitude is the Coriolis force strong enough for cyclone formation?
At least 5° latitude, as the Coriolis force is too weak at the equator.
What is the eye of a cyclone?
A calm, low-pressure region at the cyclone’s center.
What is the eyewall of a tropical cyclone?
The most intense part of the storm, surrounding the eye with maximum winds and rainfall.
What are rain bands in a cyclone?
Spiral bands of thunderstorms that rotate around the cyclone and bring heavy rain.
How do trade winds influence the movement of tropical cyclones?
They push cyclones westward, guiding their early movement.
What happens to a cyclone when it moves over land?
It weakens as it loses its source of moisture and heat.
How does vertical wind shear affect cyclogenesis?
Low wind shear allows the system to strengthen, while high wind shear disrupts it.
What is a warm-core system?
A tropical cyclone that maintains warm air at its center throughout its development.
What temperature must ocean water be for a cyclone to form?
27°C or higher, extending to a depth of 60–70 meters.
Why is a pre-existing disturbance important for cyclogenesis?
It acts as a starting point for convection and rotation.
What is the adiabatic lapse rate, and how does it impact cyclogenesis?
The cooling of rising air, leading to condensation and release of latent heat.
What is upper-level divergence, and why is it necessary?
It removes rising air, allowing the system to maintain low pressure and strengthen.
What causes an intensification of a tropical cyclone?
Continuous moisture supply, strong convection, and low vertical wind shear.
Why do cyclones have a parabolic movement?
Due to trade winds, Coriolis effect, and westerlies at higher latitudes.
