Paper Reviewed
Yang, S.-H. and Riyu, L.U. 2014. Predictability of the East Asian winter monsoon indices by the coupled models of ENSEMBLES. Advances in Atmospheric Sciences 31: 1279-1292.

Setting the stage for their work, Yang and Riyu (2014) write that the East Asian Winter Monsoon (EAWM) "is an important climate feature over East Asia, and is one of the most significant components of the global circulation system," citing Huang et al. (2003), Chan and Li (2004), Chang et al. (2006) and Huang et al. (2007). And in light of this fact, they thought it important to investigate the seasonal predictability of various EAWM indices based on hindcasts of five state-of-the-art global coupled atmosphere-ocean climate models for the 46-year period of 1961-2006, which "fully coupled prediction systems," as they describe them, "come from a new seasonal-to-annual multi-model named ENSEMBLES" that was developed by "an EU-funded integrated project" that is described by van der Linden and Mitchell (2009). And what did they thereby learn?

The two Chinese researchers report that the ENSEMBLES multi-model predicted 5 out of the 21 EAWM indices rather well. However, they say that all other indices "show low predictability," including "two residual lower-tropospheric wind indices and all the east-west pressure gradient and East Asian trough indices." They also indicate that "the prediction skill for surface air temperature is low over the majority of the East Asian region." In addition, they found that "the models cannot reproduce the observed relationship between the indices in different categories, implying that the current models may not capture the tropical-extratropical interaction related to the EAWM variability."

In light of their several negative findings, the two climate scientists conclude their paper by stating the obvious, i.e., that "the relationship between EAWM predictability and atmosphere-ocean interaction needs to be further investigated." Indeed, success in only five out of a total of twenty-one separate challenges is a far cry from satisfactory.

References
Chan, J.C.L. and Li, C.Y. 2004. The East Asia winter monsoon. In: Chang, C.P. (Ed.). East Asian Monsoon. World Scientific Publishing Co., Pet. Ltd., p. 54-106.

Chang, C.-P., Wang, Z. and Hendon, H. 2006. The Asian winter monsoon. In: Wang, B. (Ed.). The Asian Monsoon. Praxis, Berlin, Germany. p. 89-127.

Huang, R.H., Chen, J.L. and Huang, G. 2007. Characteristics and variations of the East Asian monsoon system and its impacts on climate disasters in China. Advances in Atmospheric Sciences 24: 993-1023.

Huang, R.H., Zhou, L.T. and Chen, W. 2003. The progresses of recent studies on the variables of the East Asian monsoon and their causes. Advances in Atmospheric Sciences 20: 55-69.

Van der Linden, P. and Mitchell, F.J.B. (Eds.) 2009. ENSEMBLES: Climate Change and Its Impact: Summary of Research and Results from ENSEMBLES Project. Met Office Hadley Centre. FitzRoy Road, Exeter EX1 3PB, United Kingdom. 160 pp.