What hindered the El Niño pattern in 2014?

• Published in: Geophysical research letters 2015-08, Vol.42 (16), p.6762-6770
• Main Authors: Min, Qingye, Su, Jingzhi, Zhang, Renhe, Rong, Xinyao
• Format: Article
• Language: English
• Subjects: Anomalies; Atmosphere; Easterlies; El Nino; El Nino events; El Niño; Evolution; Extreme values; Foundations; Interdecadal Pacific Oscillation; Marine; Meteorology; Obstacles; Ocean currents; Ocean temperature; Ocean-atmosphere interaction; Ocean-atmosphere system; Oceans; Oscillations; Pacific Meridional Mode; Sea surface; Sea surface temperature; Sea surface temperature anomalies; Summer; Surface temperature; Temperature anomalies; Temperature effects; Trade; Trade winds; Wind; Winds; Winter
• ISSN: 0094-8276; 1944-8007
• DOI: 10.1002/2015GL064899

At the beginning of 2014, an El Niño event was predicted to occur in the following winter. However, the El Niño that started to develop in 2014 was hindered in the boreal summer, and only the ocean reached a weak El Niño condition. This outcome was largely attributed to a suppressed ocean‐atmosphere interaction caused by anomalous easterly winds in the eastern equatorial Pacific. These winds were related to negative sea surface temperature anomalies (SSTAs) in the southeastern subtropical Pacific (SESP). The negative phase of the Interdecadal Pacific Oscillation (IPO) laid the foundation for the persistence of cooler SSTAs and enhanced trade winds in the SESP after the year 2000. As the recent IPO downward trend continued, the SSTAs in SESP reached an extremely low value in the boreal summer of 2014 and imposed a serious obstacle to the evolution of a warming event. Key Points An El Niño was predicted to occur in 2014, but its development was hindered in the boreal summer The atmosphere‐ocean interaction was suppressed in the central tropical Pacific An extreme cooling in the SESP imposed a serious obstacle to the evolution of 2014 warming event