---
title: "EQUINOO: Equatorial Indian Ocean Oscillation"
description: "EQUINOO is the atmospheric arm of the Indian Ocean Dipole over the equatorial belt, shaping Indian monsoon rainfall. How it differs from IOD and ENSO, for UPSC."
url: "https://modeldiplomat.com/learn/glossary/equatorial-indian-ocean-oscillation"
---

[New](https://modeldiplomat.com/)

#

Model Diplomat Research Team · Last reviewed June 22, 2026

TL;DR

- EQUINOO is an atmospheric oscillation over the equatorial Indian Ocean, defined by zonal wind and convection variations, that influences the Indian summer monsoon rainfall.
- How does EQUINOO differ from the Indian Ocean Dipole (IOD)?
- Why was EQUINOO important for understanding the 2002 monsoon drought?
- What does a positive phase of EQUINOO mean for the Indian monsoon?
- Which agencies use EQUINOO in monsoon forecasting?

[Civil Service & Diplomatic Exams](https://modeldiplomat.com/learn/civil-services/glossary)Updated June 22, 2026

Go beyond the definition

## Research Equatorial Indian Ocean Oscillation (EQUINOO) like a delegate

Model Diplomat's AI drafts position papers, speeches, and country research with real sources — built for MUN and politics students.

## Research it like a delegate

Research on modeldiplomat.com

## Ask a follow-up about Equatorial Indian Ocean Oscillation (EQUINOO)

Open a cited briefing in Model Diplomat search — timelines, positions, and sources you can use in committee or exam answers.

[Start research on Equatorial Indian Ocean Oscillation (EQUINOO)](https://modeldiplomat.com/search?q=Explain%20Equatorial%20Indian%20Ocean%20Oscillation%20\(EQUINOO\)%20%E2%80%94%20key%20dates%2C%20actors%2C%20positions%2C%20and%20sources)

Example

In 2002, India suffered a severe monsoon rainfall deficit despite no strong El Niño, a shortfall that climate scientists Sulochana Gadgil and colleagues attributed largely to an unfavourable negative phase of EQUINOO.

Keep learning

## Go deeper than the definition

[Explore all Civil Service & Diplomatic Exams lessons](https://modeldiplomat.com/learn/civil-services)[Test yourself with a quiz](https://modeldiplomat.com/learn/glossary/quiz/civil-services)

## Take Equatorial Indian Ocean Oscillation (EQUINOO) beyond the glossary

Ask the AI research engine built for diplomacy — get briefings, position papers, and speeches with sources you can cite in committee.