El Niño-Southern Oscillation

This recipe is available via AutoAssess.

Overview

ENSO

Available recipes and diagnostics

The assessment code is available from the AutoAssess repository.

Definition of Nino regions: Nino 1+2 (0-10S, 90W-80W), Nino 3 (5N-5S, 150W-90W), Nino 3.4 (5N-5S, 170W-120W), Nino 4 (5N-5S, 160E-150W)

Performance metrics:

• Standard deviation of Nino3 sea surface temperature (SST) anomalies

• Standard deviation of Nino4 SST anomalies

• Nino3 SST anomaly power spectrum in 3-7 year frequency range

• Standard deviation of Nino4 precipitation anomalies

• Annual mean Nino3 SST

• Annual mean Nino4 zonal wind stress (TAUX)

• Standard deviation of Nino3 SST annual cycle

• Correlation of Nino3 SST and Southern Oscillation Index (mean sea level pressure anomaly, Tahiti minus Darwin)

Diagnostics:

• Time series for sea surface temperature for areas Nino1+2, Nino3, Nino3.4 and Nino4

• Annual mean sea surface temperature (5N-5S) and zonal wind stress (5N-5S) for Pacific longitudes

• Seasonal cycle of standard deviation of Nino3 sea surface temperature “phase locking”

• Nino3 sea surface temperature power spectrum

• Composite sea surface temperature (tropical Pacific) for DJF and JJA for El Nino (Nino3.4>0.8) and La Nina (Nino3.4<0.8) composites

• Composite MSLP anomalies (global) for DJF and JJA for El Nino and La Nina

• Composite MSLP anomalies (N. Hem) for JFM (late winter) for El Nino and La Nina

• Composite precipitation anomalies (global) for DJF and JJA for El Nino and La Nina

• Likelihood of impact for selected regions for 1.5m temperature and precipitation

User settings in recipe

There are no user settings for this recipe

Variables

Variable/Field name	realm	frequency
Sea surface temperature	Atmosphere	monthly mean
TAUX	Atmosphere	monthly mean
Precipitation	Atmosphere	monthly mean
Mean sea level pressure	Atmosphere	monthly mean
1.5m temperature	Atmosphere	monthly mean

Observations and reformat scripts

Sea surface temperature: HadISST Zonal mean wind stress: NOC, MERRA Mean sea level pressure: NCEP reanalysis Precipitation: CMAP, GPCP Near surface temperature: NCEP reanalysis

How to obtain the data:

All data can be downloaded free of charge

References

Bellenger, H., Guilyardi, É., Leloup, J., Lengaigne, M. and Vialard, J., 2014. ENSO representation in climate models: from CMIP3 to CMIP5. Climate Dynamics, 42(7-8), pp.1999-2018.

Davey, M. K., A. Brookshaw, and S. Ineson, 2014: The probability of the impact of ENSO on precipitation and near-surface temperature. Climate Risk Management, 1, 5-24, doi:10.1016/j.crm.2013.12.002.

Example plots

Summary overview of metrics from the ENSO assessment

ENSO Timeseries

ENSO Phaselocking

SST and Surface Stress

Power Spectral Density

Teleconnections using 1.5m temperature

Teleconnections using precipitation