• Three-month-mean SST and sea level anomalies forecast in the equatorial Pacific.
  
  

  SST forecast

  sea level forecast

  
  

• Time evolution of SST anomalies for the Nino3.4 (170W-120W, 5S-5N) regions up to 12 lead month.
  
  

  Nino3.4 SST forecast

  
  

• Verification of monthly and seasonal SST anomaly forecast for the NINO3.4 (170W-120W, 5S-5N) region (lead month is defined as the time between the time of forecast and the beginning of predicted periods).
  
  

  monthly forecast

  seasonal forecast

• Verification of sea level anomalies at tide gauges (lead month is defined as the time between the time of forecast and the beginning of predicted periods).
  
  
  

  Santa Cruz	Baltra	Saipan	Yap	Malakal	Pohnpei	Kapingamar	Nauru	Tarawa
  Majuro	Kanton	Penrhyn	Christmas	Papeete	Funafuti	Honiara	Rabaul	Nuku Hiva
  La Liberta	Davao	Wake	Johnston	Truk	Kwajalein	Gaum	Pago Pago	Hilo

Forecasts of the tropical Pacific SST and sea level anomalies are presented here using a linear statistical model (Markov model). The Markov model is constructed in a reduced multivariate EOF space of observed sea surface temperature (SST) and sea level analysis using the methodology of Xue and Leetmaa (2000). The SST is the NCEP SST analysis (Reynolds and Smith 1994); the sea level is from the NCEP ocean analysis (Behringer et al. 1998). All the data are monthly values averaged in grid boxes of 6 degrees in longitude and 2 degrees in latitude, and cover the tropical Pacific region within 19 degrees of the equator. The model is trained for the 1981-1998 period, and is built with three multivariate EOFs in which the anomalous fields of SST and sea level are equally weighted. The model contains 12 monthly regression matrices (Xue et al. 2000).

• Verification of cross-validated monthly and seasonal SST anomalies for the NINO3.4 (170W-120W, 5S-5N) region (lead month is defined as the time between the time of forecast and the beginning of predicted periods).
  
  

  monthly forecast

  seasonal forecast

• The cross-validated skill of SST in 1981-98.
  
  

  SST

  
  

• The cross-validated skill of sea level against sea level analysis and tide gauge observations.
  
  

  sea level analysis

  tide gauge

  
  

• Cross-validated sea level anomaly hindcast at tide gauges.
  
  

  Christmas

  Yap

  Malakal

• Text file of the anomalous monthly SST for the Nino3.4 (170W-120W, 5S-5N) regions.
  
  

  anomalous monthly NINO3.4 SST forecasts

  
  

• Text files of the anomalous seasonal SST for the Nino3.4 (170W-120W, 5S-5N) regions.
  
  

  anomalous seasonal NINO3.4 SST forecasts

  
  

• Text files of the monthly SST for the Nino3.4 (170W-120W, 5S-5N) regions.
  
  

  monthly NINO3.4 SST forecasts

  
  

• Text files of the seasonal SST for the Nino3.4 (170W-120W, 5S-5N) regions.
  
  

  seasonal NINO3.4 SST forecasts

  
  
  

  The Markov model forecasts are published quarterly in Pacific ENSO Update . Further details on current conditions of El Nino and El Nino forecasts are found in Climate Diagnostics Bulletin from Climate Prediction Center .

  References

  Xue, Y. and A. Leetmaa, 2000: Forecasts of tropical Pacific SST and sea level using a Markov model. Geophys. Res. Lett. , 27, 2701-2704.

  Xue, Y., A. Leetmaa, and M. Ji, 2000: ENSOprediction with Markov models: The impact of sea level. J. Climate, 13, 849-871.

  Xue, Y., M. A. Cane, S. E. Zebiak, and B. Blumenthal, 1994: On the prediction of ENSO: a study with a low-order Markov model. Tellus , 46A , 512-528.

  Please email your comments to: Dr. Yan Xue

  Go to Yan Xue's home page.