- Climate Prediction Center: Frequently Asked Questions about El Niño and La Niña - Includes general questions, present conditions, forecasts, impacts on the US and worldwide, predicting and monitoring.
- CPC - La Niña/El Niño Coverage - Regularly updated discussion and coverage of the La Niña/El Niño weather system including global and regional impacts and forecasting.
- CPC El Niño/Southern Oscillation (ENSO) - Coverage of the weather system from the Climate Prediction Centre, including forecasts, historical info, and the impact of the system on weather patterns.
- El Niño/La Niña Watch - Archive of images and news releases about observations of the El Nino/La Nina phenomenon in the Pacific Ocean by the U.S./French TOPEX/Poseidon, Jason-1, and other NASA/JPL satellites and instruments.
- Nature's Vicious Cycle: El Nino La Nina - Project by students for students explaining these phenomena.
- What is an El Niño? - Illustrated explanation with realtime graphics and animations of data from the tropical Pacific Ocean. From NOAA.
- What is La Niña? - Illustrated explanation with realtime graphics and animations of data. Also numerous links to reference material from NOAA.
