ENSO Tracker - May 2022
Sea surface temperature (SST) forecasts for Jun – Aug 2022 still indicate cool conditions across most of the equatorial Pacific (Fig. 1). Current 3.4/4 anomalies remain well below the La Niña threshold and show recent cooling (Fig. 2), although sub-surface warming may indicate a more towards neutral conditions. ENSO outlooks generally see La Niña lasting well into summer, with some indications of La Niña lasting into fall and winter 2022.
Forecast Roundup: On May 10 the Australian Bureau of Meteorology ENSO outlook saw La Niña indicators as having “maintained or slightly increased their strength” but highlighted warming sub-surface waters as an indicator a possible return to neutral conditions. On May 12 the Japanese Meteorological Agency (JMA) observed La Niña conditions had 70-percent chance of continuing through early summer, and equally likely of continued La Niña (50%) or ENSO-neutral (50%) by fall. On May 12 the NOAA Climate Prediction Center (CPC) maintained their “La Niña Advisory” noting “the coupled ocean-atmosphere system reflected the continuation of La Niña” and called for a 58-percent chance of La Niña in late summer (Aug-Oct), and a 61-percent chance of La Niña in fall and winter 2022. On May 12 the International Research Institute (IRI) issued an ENSO Quick Look (Fig. 3), noting “Sea Surface Temperatures remain below-average (strengthening slightly) in the central-eastern equatorial Pacific”, and their objective (model-based) forecast sees roughly equal chances between La Nina and ENSO-neutral, while the ‘subjective’ (forecaster consensus) outlook favors a continuation of La Nina through summer and fall. The North American Multi-Model Ensemble (solid and dashed black line, Fig. 4) remains in La Niña territory, and in a shift from previous months, now shows persistence of La Nina conditions into Fall 2022.
Summary: The outlooks this month continue the possibility of La Nina extending into fall and winter 2022, although there is considerable uncertainty in models and forecasts during the so-called spring predictability barrier. If La Niña does persist through summer, the potential influence on the monsoon is not well understood, partly due to the inherent variability and volatility of the monsoon, and limited sample size of ENSO events that persist over the summer period.
- Figure 1 - Australian Bureau of Meteorology - bom.gov.au/climate/enso
- Figure 2 - NOAA - Climate Prediction Center - cpc.ncep.noaa.gov
- Figure 3 - International Research Institute for Climate and Society - iri.columbia.edu
- Figure 4 - NOAA - Climate Prediction Center - cpc.ncep.noaa.gov