Research notes and updates from the team.
La Niña strengthened during October, with below-average sea surface temperatures (SSTs) evident across most of the equatorial Pacific. The early November CPC/IRI SST forecast in the equatorial Pacific indicates very high probabilities (~ 90%) of La Niña during the Northern Hemisphere winter, but waning gradually to the ENSO-neutral state after February 2022.
Read more →In mid-October 2021, Sea Surface Temperature (SST) anomalies are below average across most of the equatorial Pacific Ocean. The September and Jul-Sep SST anomalies in NINO3.4 region (5S-5N; 170W-120W) were close to average, however, the most recent weekly (13OCT2021) SST anomaly was -0.8 C, which is well below average and is within the weak La Niña range.
Read more →The oceanic and atmospheric patterns in the tropical Pacific during September are consistent with La Niña. The early October CPC/IRI sea surface temperature (SST) forecast in the eastern equatorial Pacific indicates high probabilities of La Niña developing during the upcoming winter, and a La Niña advisory has been issued accordingly.
Read more →Note: The SST anomalies cited below refer to the OISSTv2 SST data set, and not ERSSTv5. OISSTv2 is often used for real-time analysis and model initialization, while ERSSTv5 is used for retrospective official ENSO diagnosis because it is more homogeneous over time, allowing for more accurate comparisons among ENSO events that are years apart.
Read more →Note: The IRI seasonal forecasts issued this month are based on the NCEP-CFSv2, CanSIPsv2, and COLA-RSMAS-CCSM4, and GFDL-SPEAR models. Current month forecast also consider the new normal period 1991-2020.
Read more →Note: The SST anomalies cited below refer to the OISSTv2 SST data set, and not ERSSTv5. OISSTv2 is often used for real-time analysis and model initialization, while ERSSTv5 is used for retrospective official ENSO diagnosis because it is more homogeneous over time, allowing for more accurate comparisons among ENSO events that are years apart.
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