Tropical System Quiz For CPL

Polar fronts generally move from west to east, and extratropical cyclones often originate along these frontal boundaries. The temperature contrast between the warm and cold air masses at the polar front can create the conditions necessary for cyclone development.

The Coriolis force, which is a result of the Earth’s rotation, is a crucial factor in the formation of cyclonic storms. At the equator, the Coriolis force is zero, preventing the development of cyclones.

Cyclonic storms typically form in regions with significant Coriolis force, such as the mid-latitudes and subtropics.

A surge is a sudden intensification of an air current within the same air mass. During a surge, air arrives at a faster rate than it can be removed, leading to an accumulation of air at the surge line and subsequent vertical ascent. This process is known as velocity convergence. Surges are common disturbances during the monsoon season over the Arabian Sea.

In a monsoon depression, the most severe weather typically occurs in the southwest sector, characterized by steady and heavy rainfall within a belt approximately 400 km wide. Elsewhere, rainfall is generally scanty. As the depression recurves, the rainbelt shifts toward the north-northeast sector. Showery precipitation often occurs in the rear of the depression when winds are strong south-southwesterly.

The associated upper-air cyclonic circulation extends to around 300 hPa. The monsoon depression slopes southwestward with height. For example, if the system is located over Kolkata at the surface, it would be found over Visakhapatnam at 300 hPa (9 km).

To avoid a tropical cyclone while in flight, if strong winds are encountered from the port side (left), the center is likely ahead. Alter the course until the wind is from the starboard side (right) and is weakening. This indicates that the aircraft is moving away from the cyclone’s center.

According to the polar-front theory, extratropical cyclones develop along a frontal surface that separates a warm air mass from a cold air mass. In a polar front, a significant temperature gradient exists between these two air masses.

The Peninsular Discontinuity (PD) is a meteorological boundary that forms over peninsular India (south of 23°N) during April and May. It is also referred to as the Dry Line.

Key characteristics:

Location: Forms between hot, dry continental air from northern India and cooler, moist air from the Bay of Bengal.
Impact: Often leads to afternoon thunderstorms, sometimes accompanied by hail, strong northwesterly squalls, and heavy showers.
Duration: Remains relatively stationary for 3-4 days before dissipating.
This discontinuity plays a significant role in the weather patterns of peninsular India during the pre-monsoon season.

Tropical cyclones typically maintain their strength over water. Once they make landfall, they tend to weaken due to increased friction and loss of energy from the ocean. This is why cyclones around India often have a relatively short lifespan of a few days.

Lack of terrain can allow tropical cyclones to move faster. When cyclones encounter mountainous regions or other land features, they can experience increased friction, which can slow their movement. However, over open water with minimal terrain, cyclones can maintain higher speeds.

The eye, a central feature of a tropical cyclone (TC), is typically 20-50 km in diameter. Its shrinking indicates increasing storm intensity. The eye has the lowest surface pressure and calmest conditions. Air forced up and out of the storm returns down the center, causing adiabatic heating and cloud evaporation, creating the clear eye column.

Monsoon depressions are low-pressure systems that form over the Bay of Bengal during the Indian monsoon season. They are characterized by:

Closed isobars: Two or more closed isobars at 2 hPa intervals.
Surface winds: 17-33 knots.
Formation: They form over the North Bay of Bengal, Arabian Sea, and sometimes over land (primarily in Northeast India).
Movement: They typically move northwest or northeast into land, with their formation location shifting from north of 18°N in June-August to around 14°N in September.
Impact: They play a crucial role in advancing the monsoon northward and bringing significant rainfall to India.
Lifespan: The average lifespan of a monsoon depression is 3-5 days.

Wind speeds can reach up to 34 knots in a storm, making it a powerful weather event.

Tropical cyclones typically move over the ocean at a speed of 15-20 kilometers per hour. This means they can travel 300-500 kilometers in a single day.

Tropical cyclones typically maintain their strength over water. Once they make landfall, they tend to weaken due to increased friction and loss of energy from the ocean. This is why cyclones around India often have a relatively short lifespan of a few days.

A tropical cyclone is a large, violent vortex with a diameter ranging from 150 to 800 kilometers. It spirals around a central point and typically moves over the sea at a rate of 15-20 kilometers per hour, covering 300-500 kilometers per day. Generally, tropical cyclones move westward up to about 25 degrees north or south latitude before recurving and turning eastward.

Tropical cyclones typically maintain their strength over water. Once they make landfall, they tend to weaken due to increased friction and loss of energy from the ocean. This is why cyclones around India often have a relatively short lifespan of a few days.

Tropical cyclones typically maintain their strength over water. Once they make landfall, they tend to weaken due to increased friction and loss of energy from the ocean. This is why cyclones around India often have a relatively short lifespan of a few days.

Tropical cyclones generally move eastward or east-northeast, guided by the westerly currents in these latitudes. When a depression on the polar front occludes, the unoccluded portion may remain behind at a lower latitude, creating favorable conditions for secondary depressions to form. This process can repeat at even lower latitudes, leading to the formation of a family of 3 or 4 depressions, often moving eastward together. These are known as cyclone families.

A surge is a sudden intensification of an air current within the same air mass. During a surge, air arrives at a faster rate than it can be removed, leading to an accumulation of air at the surge line and subsequent vertical ascent. This process is known as velocity convergence. Surges are common disturbances during the monsoon season over the Arabian Sea.

Surge: A surge is a sudden intensification of an air current within the same air mass. During a surge, air arrives at a faster rate than it can be removed, leading to an accumulation of air at the surge line and subsequent vertical ascent. This process is known as velocity convergence. Surges are common disturbances during the monsoon season over the Arabian Sea.

Shear Line: A shear line is a boundary within an air mass where wind speed or direction changes rapidly. This change in wind velocity creates friction, leading to a small-scale upward movement of air known as a shear line surge. Shear lines are characteristic features of vigorous monsoon activity.

Warm Ocean Waters: Sea surface temperatures must exceed 26°C to a depth of at least 60 meters to provide abundant evaporation.
High Relative Humidity: Relative humidity must be above 7000 meters to facilitate the condensation of water vapor into droplets and release latent heat, which induces a drop in pressure.
Atmospheric Instability: The atmosphere must be unstable to allow for vertical development of air masses.
Coriolis Force: The Coriolis force, a result of Earth’s rotation, is necessary to deflect winds inward and create a spiraling pattern.

The Peninsular Discontinuity (PD) is a meteorological boundary that forms over peninsular India (south of 23°N) during the pre-monsoon months of April and May.

Key characteristics:

Location: Forms between hot, dry continental air from northern India and cooler, moist air from the Bay of Bengal.
Impact: Often leads to afternoon thunderstorms, sometimes accompanied by hail, strong northwesterly squalls, and heavy showers.
Duration: Remains relatively stationary for 3-4 days before dissipating.
This discontinuity plays a significant role in the weather patterns of peninsular India during the pre-monsoon season. It can contribute to localized convective activity and precipitation in regions adjacent to the boundary.

Tropical cyclones generally move eastward or east-northeast, guided by the westerly currents in these latitudes. When a depression on the polar front occludes, the unoccluded portion may remain behind at a lower latitude, creating favorable conditions for secondary depressions to form. This process can repeat at even lower latitudes, leading to the formation of a family of 3 or 4 depressions, often moving eastward together. These are known as cyclone families.

Warm Ocean Waters: Sea surface temperatures must exceed 26°C to a depth of at least 60 meters to provide abundant evaporation.
High Relative Humidity: Relative humidity must be above 7000 meters to facilitate the condensation of water vapor into droplets and release latent heat, which induces a drop in pressure.
Atmospheric Instability: The atmosphere must be unstable to allow for vertical development of air masses.
Coriolis Force: The Coriolis force, a result of Earth’s rotation, is necessary to deflect winds inward and create a spiraling pattern.

The pressure gradient is very steep in the inner storm area, typically ranging from 50 to 150 kilometers. This steep gradient contributes to the strong winds and intense weather associated with tropical cyclones.