Dynamical seasonal climate prediction using an ocean-atmosphere coupled climate model developed in partnership between South Africa and the IRI

Beraki, Asmerom FDe Witt, DGLandman, WAOlivier, C2014-06-172014-06-172014-02Beraki, A.F, De Witt, D.G, Landman, W.A and Olivier, C. 2014. Dynamical seasonal climate prediction using an ocean-atmosphere coupled climate model developed in partnership between South Africa and the IRI. Journal of Climate, vol. 27, pp0894-8755http://journals.ametsoc.org/doi/abs/10.1175/JCLI-D-13-00275.1http://hdl.handle.net/10204/7482Copyright: 2014 American Meteorological Society. This is an Open Access journal. The journal authorizes the publication of the information herewith contained. Published in Journal of Climate, vol. 27, pp 1719-1741The recent increase in availability of high-performance computing (HPC) resources in South Africa allowed the development of an ocean–atmosphere coupled general circulation model (OAGCM). The ECHAM4.5-South African Weather Service (SAWS) Modular Oceanic Model version 3 (MOM3-SA) is the first OAGCM to be developed in Africa for seasonal climate prediction. This model employs an initialization strategy that is different from previous versions of themodel that coupled the same atmosphere and ocean models. Evaluation of hindcasts performed with the model revealed that the OAGCM is successful in capturing the development and maturity of El Nino and La Nina episodes up to 8 months ahead. A model intercomparison also indicated that the ECHAM4.5-MOM3-SA has skill levels for the Nino-3.4 region SST comparable with other coupled models administered by international centers. Further analysis of the coupled model revealed that La Nina events aremore skillfully discriminated than El Nino events. However, as is typical for OAGCM, the model skill was generally found to decay faster during the spring barrier. The analysis also showed that the coupled model has useful skill up to several-months lead time when predicting the equatorial Indian Ocean dipole (IOD) during the period spanning between the middle of austral spring and the start of the summer seasons, which reaches its peak in November. The weakness of the model in other seasons was mainly caused by the western segment of the dipole,which eventually contaminates the dipole mode index (DMI). The model is also able to forecast the anomalous upper air circulations, particularly in the equatorial belt, and surface air temperature in the Southern African region as opposed to precipitation.enSeasonal forecastingOcean-atmosphere coupled modelEl Niño–Southern OscillationENSOClimate predictionCoupled climate modelDynamical seasonal climate prediction using an ocean-atmosphere coupled climate model developed in partnership between South Africa and the IRIArticleBeraki, A. F., De Witt, D., Landman, W., & Olivier, C. (2014). Dynamical seasonal climate prediction using an ocean-atmosphere coupled climate model developed in partnership between South Africa and the IRI. http://hdl.handle.net/10204/7482Beraki, Asmerom F, DG De Witt, WA Landman, and C Olivier "Dynamical seasonal climate prediction using an ocean-atmosphere coupled climate model developed in partnership between South Africa and the IRI." (2014) http://hdl.handle.net/10204/7482Beraki AF, De Witt D, Landman W, Olivier C. Dynamical seasonal climate prediction using an ocean-atmosphere coupled climate model developed in partnership between South Africa and the IRI. 2014; http://hdl.handle.net/10204/7482.TY - Article AU - Beraki, Asmerom F AU - De Witt, DG AU - Landman, WA AU - Olivier, C AB - The recent increase in availability of high-performance computing (HPC) resources in South Africa allowed the development of an ocean–atmosphere coupled general circulation model (OAGCM). The ECHAM4.5-South African Weather Service (SAWS) Modular Oceanic Model version 3 (MOM3-SA) is the first OAGCM to be developed in Africa for seasonal climate prediction. This model employs an initialization strategy that is different from previous versions of themodel that coupled the same atmosphere and ocean models. Evaluation of hindcasts performed with the model revealed that the OAGCM is successful in capturing the development and maturity of El Nino and La Nina episodes up to 8 months ahead. A model intercomparison also indicated that the ECHAM4.5-MOM3-SA has skill levels for the Nino-3.4 region SST comparable with other coupled models administered by international centers. Further analysis of the coupled model revealed that La Nina events aremore skillfully discriminated than El Nino events. However, as is typical for OAGCM, the model skill was generally found to decay faster during the spring barrier. The analysis also showed that the coupled model has useful skill up to several-months lead time when predicting the equatorial Indian Ocean dipole (IOD) during the period spanning between the middle of austral spring and the start of the summer seasons, which reaches its peak in November. The weakness of the model in other seasons was mainly caused by the western segment of the dipole,which eventually contaminates the dipole mode index (DMI). The model is also able to forecast the anomalous upper air circulations, particularly in the equatorial belt, and surface air temperature in the Southern African region as opposed to precipitation. DA - 2014-02 DB - ResearchSpace DP - CSIR KW - Seasonal forecasting KW - Ocean-atmosphere coupled model KW - El Niño–Southern Oscillation KW - ENSO KW - Climate prediction KW - Coupled climate model LK - https://researchspace.csir.co.za PY - 2014 SM - 0894-8755 T1 - Dynamical seasonal climate prediction using an ocean-atmosphere coupled climate model developed in partnership between South Africa and the IRI TI - Dynamical seasonal climate prediction using an ocean-atmosphere coupled climate model developed in partnership between South Africa and the IRI UR - http://hdl.handle.net/10204/7482 ER -