Relevance for UPSC: GS Paper I (Physical Geography), GS Paper III (Disaster Management, Climate Change)
Source: The Hindu ; Studies and cyclone data of the India Meteorological Department

Context

Recent studies show that cyclone behaviour in the North Indian Ocean—covering the Bay of Bengal and the Arabian Sea—is undergoing a systemic shift, largely driven by ocean warming linked to climate change.

Key Changes Observed

• Lower frequency, higher intensity:
  The total number of cyclones has declined, but a larger proportion now intensifies into severe and very severe cyclonic storms.
• Rising role of the Arabian Sea:
  Earlier dominated by the Bay of Bengal, the Arabian Sea now records more intense cyclones, with frequent rapid intensification due to higher sea surface temperatures.
• Shift in seasonality:
  Cyclone formation is increasingly concentrated in the post-monsoon months (October–December), extending the risk period.

Underlying Cause

• Warmer oceans provide more latent heat energy, leading to stronger but fewer cyclones.

Q. Which of the following changes has been observed in cyclones over the North Indian Ocean in recent decades?

1. Decline in total number but rise in severe cyclones
2. Increased intensity of cyclones in the Arabian Sea
3. Shortening of the cyclone season

Select the correct answer using the code below:
(a) 1 and 2 only
(b) 2 and 3 only
(c) 1 and 3 only
(d) 1, 2 and 3