El Niño/La Niña Watch & PDO

El Niño: 1997-1998 vs. 2015-2016

The super El Niño of 2015-2016 was the biggest, so far, of the 21st Century. Below are side by side comparisons of Pacific Ocean sea surface height (SSH) anomalies during the 2015-16 event with the famous 1997-1998 El Niño.

December 1997 vs. December 2015 El Nino events — This image shows the December 1997 vs. December 2015 El Niño events. **Larger image**

Although there are similarities between El Niño events, each one has a unique timing and variations in impacts. The 1997-98 El Niño peaked in November 1997. The 2015-16 El Niño, which peaked in January 2016, was longer lasting and was larger in area than the 1997-1998 episode.

In 2014-2015 there was a weak, central Pacific El Niño, so the El Niño of 2015-16 had a jump start. The 1997-98 El Niño was followed by a strong La Niña event, while a mild La Niña followed the 2015-16 El Niño – reminding us yet again, that each El Niño event is different.

The 1997-1998 and 2015-2016 El Niño animations below were made from data collected by the TOPEX/Poseidon (1997-1998) and the OSTM/Jason-2 (2015-2016) satellites.

Since 1992, TOPEX/Poseidon, Jason-1, Jason-2 and Jason-3 have successively used space-based radar altimetry to collect sea surface height data of all the world's oceans. These images are processed to highlight the interannual signal of SSH – the mean signal, seasonal signal, and the trend have been removed.

Animation options:

1997-1998 vs. 2015-2016 Comparison

Full sized - 2000px (GIF, 71.4 MB)
Medium - 800px (GIF, 14.6 MB)
Small - 485px (GIF, 6 MB)
MP4 - 10fps (52.2 MB)

2015-2016 Only

2015-2016 Only (GIF, 53.9 MB)

To learn more, read What is sea-surface height?