El Niño/La Niña in CPD

Tsurane Kuragano El Niño Group, CPD, JMA

Contents

Ocean Analysis and Prediction models Latest Conditions in equatorial Pacific Future Challenges

monitoring and prediction 2-1. Ocean Data Assimilation System 2-2. El Nino Prediction Model (Ocean-Atmosphere Coupled Model)

El Niño monitoring and prediction system

Schematic diagram of system Configurations of system

Horizontal Resolution 1 deg. EW 1 deg. NS 0.3 deg. (NS) for the equatorial region

Veritical Resolution 50 levels 29 levels for top 300 m

for detail of thermocline structure

MRI.COM: Meteorological Research Institute Community Ocean Model

depth surface for detail of the equatorial region

Ocean General Circulation Model

Ocean Data Assimilation System MOVE/MRI.COM MOVE: Multivariate Ocean Variational Estimate

3D-VAR: 3-D Variational Method. An analysis method for seeking for the physically-consistent optimal data field that is expected to have the least deviation from the true value based upon statistical assumptions.

Ocean observing network for El Niño monitoring

Specifications of El Niño Prediction model -Atmospheric component : spectral model (TL95, 192x96 grids, 40 vertical levels)

-Ocean component : OGCM (MRI.COM)

-Initial condition :

[atmosphere] provided by JCDAS (JMA Climate Data Assimilation System)

[ocean] provided by MOVE/MRI.COM

-Prediction period : up to 7 months ahead

-12-member ensemble forecast

170W-120W, 5N-5S

Prediction model performance

RMS Error Anomaly Correlation

Red Solid JMA/MRI-CGCM Red Broken JMA-CGCM02 (former model) (1979.1.1 2003.12.2)

The former model was operated until Feb. 2008.

3. Latest Conditions Monthly mean SSTA October 2008

Nino3 SSTA

SOI

Subsurface Condition

Sept.23-Sept.27

Oct.8-Oct.12

Oct.23-Oct.27 Temp of Depth-Longitude Section along Equator OHC of Time-Longitude Section along Equator

Atmospheric Condition

Lagged-averaged Forecast (LAF), 12 members

Analysis

Predictions

Prediction of Niño3 SSTA

70% probability

5-month running mean

Different models tell different predictions?

from International Research Institute for Climate and Society, Columbia Univ.,USA

170W-120W, 5N-5S

http://iri.columbia.edu/climate/ENSO/currentinfo/SST_table.html#figure

4. Future Challenges

Following developments are planned:

- Improvement in ensemble generation method (March 2009)

- Information on oceanic conditions in the western equatorial Pacific and the Indian Ocean (July 2009)

- Introduction of the atmosphere-ocean coupled model into operational seasonal forecast (March 2010)

Improvement in ensemble generation method

Present system: Lagged-Averaged Forecast (LAF), 12 members

New system: Adding perturbations to forcing in ODAS, etc., 30 members

Present system

Information on oceanic conditions in the western equatorial Pacific and the Indian Ocean

NINO.3

Impacts on global climate ?

Model and assimilation improved Ocean observations increased

Region for monitoring and outlook can be expanded

Impacts on global climate will be investigated.

Introduction of the atmosphere-ocean coupled model into operational seasonal forecast

Present System

Atmospheric Analysis

Oceanic Analysis Coupled Model NINO.3 Forecast

SST Forecast

Statistical Model

Atmospheric Model

Seasonal Forecast

Introduction of the atmosphere-ocean coupled model into operational seasonal forecast

Future System

Atmospheric Analysis

Oceanic Analysis Coupled Model SST Forecast

Seasonal Forecast

Thank you for your attention