Why do cyclones move towards land?

IN NEWS:

Why do cyclones move towards land? – Explained (The Hindu, October 28, 2025)

UPSC ANALYSIS

1. Context:

Cyclone Montha’s track and forecast have prompted a deeper understanding of why tropical cyclones generally move towards land, especially along India’s eastern and western coasts.2. Cyclone Movement – Core Idea:

• Tropical cyclones are carried by large-scale atmospheric wind patterns.
• Their formation region (5°–20° N/S latitude) is governed by trade winds, blowing east to west due to Hadley circulation and the Coriolis effect.
• Thus, cyclones in the Bay of Bengal typically move westward towards India, while those in the Atlantic move from Africa towards the Americas.

3. Key Atmospheric Mechanisms:

• Hadley Circulation: Warm air rises near the equator, moves poleward, cools and sinks around 30° latitude, completing a convection loop.
• Coriolis Effect: Earth’s rotation deflects moving air, generating easterly trade winds.
• These winds steer cyclones westward, leading to frequent landfalls in tropical coastal regions.

4. Role of Monsoon Winds in the Indian Ocean:

• The Indian Ocean differs from Atlantic/Pacific due to reversing monsoon winds.
• June–September (Southwest Monsoon): Winds blow from southwest to northeast → Cyclones in Arabian Sea are steered towards India’s west coast (Gujarat, Maharashtra, Kerala).
• Winter–Spring (Northeast Monsoon): Winds reverse, blowing from land to sea → Cyclones tend to drift westward towards Arabian Peninsula or Somalia, though rare due to cooler waters and stronger wind shear.

5. Notable Example:

• Cyclone Michaung (2023): Moved slowly due to weak steering winds over the Bay of Bengal, causing prolonged coastal impact before landfall.

6. Broader Understanding:

• If global geography or wind directions were reversed, cyclones would seldom make landfall, as they’d be carried over open waters.
• Hence, India’s tropical location, monsoon dynamics, and wind patterns make it particularly vulnerable to recurrent cyclone strikes.

STATIC PART

Key Terms & Concepts:

• Trade Winds: Permanent east-to-west surface winds found in tropics, part of Hadley circulation.
• Coriolis Effect: Deflection of moving air/water due to Earth’s rotation, rightward in Northern Hemisphere, leftward in Southern Hemisphere.
• Hadley Cell: Atmospheric convection loop between equator and 30° latitude; drives trade winds.
• Cone of Uncertainty: Forecast area within which a cyclone’s center is expected to move.
• Landfall: The event when a cyclone’s center crosses the coast from sea to land.
  
  Updated - October 28, 2025 09:39 am | The Hindu