How El Niño Shaped Path and Intensity of Cyclone Arnab

Key Highlights & Summary 

• Cyclone Arnab formed as the first cyclone of 2026 in the North Indian Ocean basin, originating from a lowpressure system in the southeast Bay of Bengal on October 23 and intensifying rapidly. 

• Under the developing El Niño scenario, warmer ocean waters with sea surface temperatures in the Niño3.4 region recording 2to2.8 degrees Celsius above normal fueled the rapid intensification of the storm into a very severe cyclonic storm. 

• While Odisha and West Bengal are typically more prone to Bay of Bengal cyclones, El Niño years alter wind patterns and air pressure, causing cyclones to affect the Andhra Pradesh and Tamil Nadu coasts instead. 

• The naming of tropical cyclones in the North Indian Ocean is managed by a panel of 13 member countries following strict guidelines, with the current name Arnab put forward by Bangladesh. 

• Tropical cyclone intensity is governed by a complex process involving boundary layers, wind shear, convection, and upper ocean circulation interaction. 

• Following landfall near Bapatla and Visakhapatnam with wind speeds equivalent to a very severe cyclone, Arnab brought heavy rainfall ranging from 64to115mm to parts of northern Andhra Pradesh and southern Odisha. 

Essential Definitions 

• El Niño: The abnormal warming of surface waters in the Pacific Ocean that suppresses monsoon rainfall, spikes temperatures, and alters global wind patterns. 

 • Tropical Cyclone: A rapidly rotating storm system characterized by a lowpressure center, strong winds, and heavy spiral rain squalls originating over tropical waters. 

 • Landfall: The event of a tropical storm moving over land after being over water, often causing maximum damage due to high winds and storm surges. 

Legal and Constitutional Framework 

• National Disaster Management Act, 2005: Provides the statutory framework for disaster management in India, establishing the National Disaster Management Authority (NDMA) headed by the Prime Minister and State and District Disaster Management Authorities to formulate holistic mitigation and response plans for events like severe cyclones. 

• Constitutional Provisions: Under the Seventh Schedule of the Constitution of India, disaster management and relief fall under concurrent and state jurisdictions, empowering state and local administrative bodies to execute swift evacuations and relief operations during weather emergencies.

Conclusion Cyclone Arnab underscores the profound influence of climatic anomalies like El Niño on shifting cyclone trajectories and intensifying storm behaviors in the North Indian Ocean basin. Effective forecasting by meteorological agencies coupled with proactive community evacuation and robust disaster management frameworks remain critical to minimizing loss of life and property along India vulnerable coastline. 

UPSC Relevance 

This topic is highly relevant for the UPSC Civil Services Examination under General Studies Paper I (Climatology, Geography of India) and General Studies Paper III (Disaster Management, Environmental Impact Assessment, and Weather Forecasting Systems). Aspirants must understand ocean-atmosphere interactions, the mechanics of El Niño, and institutional disaster response frameworks.