The impact of the extratropics on ENSO diversity and predictability

Pegion, Kathy; Selman, Christopher; Larson, Sarah M.; Furtado, Jason C.; Becker, Emily

doi:10.1007/s00382-020-05232-3

Cited by 11 publications

(13 citation statements)

References 67 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Note that the number of CP events is small according to our definition (see Text S3 in Supporting Information ) so the result may lack robustness. However, this result is consistent with previous studies that extratropical ENSO precursors have a stronger connection to CP‐ENSO compared to EP‐ENSO (Capotondi & Ricciardulli, 2021; Pegion et al., 2020). Previous studies also have demonstrated a stronger impact from the northern extratropics (e.g., the NPMM, consisting of SST anomalies extending from Baja California to the central‐western equatorial Pacific) for CP‐ENSO than EP‐ENSO (Amaya et al., 2019; D. J. Vimont et al., 2014; Yu & Kim, 2011).…”

Section: Summary and Discussionsupporting

confidence: 93%

“…Note that here we emphasize the role of the extratropical Pacific in crossing the SPB of ENSO. Previous studies have shown the impacts of extratropical Pacific on the predictability of ENSO (e.g., Chen et al, 2020;Pegion et al, 2020;Tseng et al, 2022). A more recent paper also discussed the influence of the north Pacific Victoria mode on the spring persistence barrier of ENSO (Shi et al, 2022).…”

Section: Summary and Discussionmentioning

confidence: 99%

“…According to this hypothesis, through the linear regression methodologies, Pegion et al. (2020) found that at a 1‐year lead time, the extratropical Pacific is responsible for the formation of CP‐ENSO, but not EP‐ENSO. Chen et al.…”

Section: Introductionmentioning

confidence: 99%

“…Since the extratropical Pacific plays an important role in triggering ENSO, it may also have potential impacts on ENSO predictability. According to this hypothesis, through the linear regression methodologies, Pegion et al (2020) found that at a 1-year lead time, the extratropical Pacific is responsible for the formation of CP-ENSO, but not EP-ENSO. Chen et al (2020) found that by combining tropical preconditions with extratropical precursors, ENSO prediction skill could be noticeably increased beyond the time scale of the SPB.…”

mentioning

confidence: 99%

See 3 more Smart Citations

The Role of Extratropical Pacific in Crossing ENSO Spring Predictability Barrier

Zhao

Jin

et al. 2022

Geophysical Research Letters

View full text Add to dashboard Cite

This paper investigates the impacts of extratropical Pacific on El Niño‐Southern Oscillation (ENSO) spring predictability barrier (SPB). Using an empirical dynamical model – Linear Inverse Model (LIM), we find that the dynamics of the northern and southern extratropical Pacific can significantly and equally weaken the Eastern Pacific (EP)‐ENSO SPB, while the North Pacific is more important for weakening the Central Pacific (CP)‐ENSO SPB. The evolution of the extratropical optimum initial structures illustrates the different roles of the northern and southern extratropical Pacific in crossing EP and CP ENSO SPBs and demonstrates the decisive role that the South Pacific initial condition plays in ENSO diversity. Additionally, the extratropical Pacific greatly influences the forecast skill of El Niño during SPB, while tropical dynamics may be more important for crossing the SPB of La Niña.

show abstract

Section: Summary and Discussionsupporting

confidence: 93%

Section: Summary and Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

mentioning

confidence: 99%

See 2 more Smart Citations

The Role of Extratropical Pacific in Crossing ENSO Spring Predictability Barrier

Zhao

Jin

et al. 2022

Geophysical Research Letters

View full text Add to dashboard Cite

show abstract

“…This makes the CP El Niño events less predictable in terms of an equatorial thermocline precursor. It is important to note that we do not rule out the predictability of CP El Niños that arises from extratropical Pacific atmospheric forcing, such as through the Pacific meridional mode or trade wind charging mechanism (Anderson et al., 2015; Chakravorty et al., 2021; Pegion et al., 2020; Timmermann et al., 2018). We recognize that extratropical precursors might be the reason for the good prediction skill of CP El Niño events in hindcast simulations (Sun et al., 2018).…”

Section: Summary and Discussionmentioning

confidence: 89%

Revisiting the Recharge and Discharge Processes for Different Flavors of El Niño

et al. 2021

View full text Add to dashboard Cite

The El Niño-Southern Oscillation (ENSO) is the most energetic air-sea coupled process on interannual time scales and profoundly impacts the global climate. ENSO is characterized by an irregular (2-7 years) oscillation of warm and cold sea surface temperature (SST) anomalies over the eastern and central equatorial Pacific. During the ENSO warm phase (El Niño), the tropical Pacific Ocean (TPO) and overlying atmosphere couple through the Bjerknes feedback mechanism (Bjerknes, 1969). The weakening of the zonal (i.e., east-west) SST gradient over the equatorial Pacific weakens the tropical easterly trade winds, further weakening the zonal SST gradient. However, this positive feedback cannot describe the turnabout of El Nino and its transition to the La Niña (ENSO cold phase). To explain the dynamics of the ENSO cycle, Wyrtki (1975, 1985 developed the "buildup and draining" hypothesis. According to this hypothesis, the excessively strong easterly trade winds build up warm water in the western equatorial

show abstract

The efficacy of tropical and extratropical predictors for long‐lead El Niño‐Southern Oscillation prediction: A study using a machine learning algorithm

Song,

Yu,

Lian

2023

Intl Journal of Climatology

View full text Add to dashboard Cite

This study illustrates the considerable improvement in accuracy achievable for long‐lead forecasts (18 months) of the Ocean Niño Index (ONI) through the utilization of a long short‐term memory (LSTM) machine learning algorithm. The research assesses the predictive potential of eight predictors from both tropical and extratropical regions constructed based on sea surface temperature, outgoing longwave radiation, sea surface height and zonal and meridional wind anomalies. In comparison to linear regression model forecasts, the LSTM model outperforms them for both the tropical and extratropical predictor sets. Among all the predictors, the western North Pacific (WNP) index demonstrates the highest prediction skill in ONI forecasts, followed by the North Tropical Atlantic (NTA) index and then the sea surface height index. While other predictors help the LSTM model to forecast either the phase variation of the amplitude variation of the observed ONI, the extratropical WNP predictor enables the LSTM model to forecast both variations. This superiority can be attributed to the involvement of SST anomalies in the WNP region in both tropical and extratropical El Niño–Southern Oscillation (ENSO) dynamics, allowing for the utilization of predictive potential from both components of ENSO dynamics. The study also concludes that the extratropical ENSO dynamics provide a robust source of predictability for long‐lead ENSO forecasts, which can be effectively harnessed using the LSTM model.

show abstract

The impact of the extratropics on ENSO diversity and predictability

Cited by 11 publications

References 67 publications

The Role of Extratropical Pacific in Crossing ENSO Spring Predictability Barrier

The Role of Extratropical Pacific in Crossing ENSO Spring Predictability Barrier

Revisiting the Recharge and Discharge Processes for Different Flavors of El Niño

The efficacy of tropical and extratropical predictors for long‐lead El Niño‐Southern Oscillation prediction: A study using a machine learning algorithm

Contact Info

Product

Resources

About