Reinitializing Sea Surface Temperature in the Ensemble Intermediate Coupled Model for Improved Forecasts

The Ensemble Intermediate Coupled Model (EICM) is a model used for studying the
El Niño-Southern Oscillation (ENSO) phenomenon in the Pacific Ocean, which is anomalies in
the Sea Surface Temperature (SST) are observed. This research aims to implement Cressman to
improve SST forecasts. The simulation considers two cases in this work: the control case and the
Cressman initialized case. These cases are simulations using different inputs where the two inputs
differ in terms of their resolution and data source. The Cressman method is used to initialize
the model with an analysis product based on satellite data and in situ data such as ships, buoys,
and Argo floats, with a resolution of 0.25 × 0.25 degrees. The results of this inclusion are the
Cressman Initialized Ensemble Intermediate Coupled Model (CIEICM). Forecasting of the sea surface
temperature anomalies was conducted using both the EICM and the CIEICM. The results show that
the calculation of SST field from the CIEICM was more accurate than that from the EICM. The forecast
using the CIEICM initialization with the higher-resolution satellite-based analysis at a 6-month lead
time improved the root mean square deviation to 0.794 from 0.808 and the correlation coefficient to
0.630 from 0.611, compared the control model that was directly initialized with the low-resolution
in-situ-based analysis.