Recent Context:
Typhoon Yagi which is the strongest tropical cyclone Asia has seen this year and the second most powerful storm in the world so far this year after Hurricane Beryl. Lakhs of people in Southeast Asia continue to struggle with torrential rains, floods, and landslides due to the typhoon.
About the Typhoon Yagi and its Impact:
1.Philippines, China, Laos, Myanmar, and Thailand,Vietnam are the highest hit, where the death toll stands at around 233. The overall toll across these countries has crossed over 300 till now.
2.According to the National Oceanic and Atmospheric Administration (NOAA). Storm systems with wind speeds of 119 kmph and above are classified as hurricanes, typhoons, or tropical cyclones.
3.It became a Category 5 typhoon with peak maximum sustained winds of 260 kmph.
4.Typhoon Yagi is one of four Category 5 storms recorded in the South China Sea, after Pamela in 1954, Rammasun in 2014, and Rai in 2021.
5.Higher sea surface temperatures are responsible for causing marine heat waves, an extreme weather event, which can also make storms like hurricanes and tropical cyclones more intense.
Formation of a Tropical Cyclone:
Tropical cyclones, also known as hurricanes or typhoons, are powerful storms that form over warm ocean waters.
They require a combination of specific conditions to develop:
-Warm Ocean Waters: The primary energy source for a tropical cyclone is warm ocean water. The water temperature must be at least 26.5°C (79.7°F) to provide the necessary heat and moisture.
-Converging Winds: Winds near the ocean surface must converge, pushing air upward and creating a low-pressure area. This upward movement helps to form thunderstorms.
-Low Wind Shear: Wind shear, the change in wind speed and direction with height, must be low. This allows thunderstorms to grow vertically and organize into a rotating system.
-Sufficient Distance from the Equator: The Coriolis effect, which causes winds to deflect to the right in the Northern Hemisphere and to the left in the Southern Hemisphere, is necessary for a tropical cyclone to spin. This effect is stronger farther from the equator.
The Formation Process:
-Trigger: A disturbance, such as a cluster of thunderstorms or a low-pressure system, forms over warm ocean waters.
-Organization: As the disturbance gathers energy from the warm water, it begins to organize and rotate.
-Intensification: The low-pressure center deepens, and the storm’s winds increase in speed.
-Maturity: The tropical cyclone reaches its peak intensity, often with strong winds, heavy rainfall, and a central eye.
-Weakening: As the storm moves over land or colder waters, it gradually weakens due to the lack of warm, moist air.
Key Points:
-Tropical cyclones are fueled by warm ocean water and can cause significant damage when they make landfall.
-Understanding the conditions necessary for their formation helps meteorologists to predict and track these powerful storms.
PYQ. Tropical cyclones are largely confined to the South China Sea, Bay of Bengal and Gulf of Mexico. Why?
(UPSC CSE MAINS 2014)
Source:
https://indianexpress.com/article/explained/explained-climate/typhoon-yagi-9567876/