Modeling the Link Between ENSO and North Australian SSTs

Catto et al. (2012b) write that "the El Niño-Southern Oscillation (ENSO) is linked to the interannual climate variability of Australia, in part through its effect on the sea surface temperatures (SSTs) around northern Australia," as has been documented by Hendon (2003) and Catto et al. (2012a). And they explain that "it is important that global coupled climate models are able to represent this link between ENSO and north Australian SSTs so that we can have more confidence in the projections of future climate change for the Australian region." Thus, the authors set out to evaluate the link between ENSO and north Australian SSTs "in the models participating in CMIP5 with a view to comparing them with the CMIP3 models evaluated in Catto et al. (2012a)."

In describing their results, the three Australian researchers report that: (1) "the CMIP5 models still show a wide range in their ability to represent both ENSO events themselves, and their relationship to north Australian SST," that (2) "most of the models fail to capture the strong seasonal cycle of correlation between the Niño-3.4 and north Australian SSTs," and that (3) "the models in general are still missing some underlying process or mechanism."

Catto et al. conclude by stating that "gaining a deeper understanding of the physical mechanism behind the strong link between the SSTs in the Niño-3.4 region and to the north of Australia using these models" is "a vital next step" for this work, which they say is required "to elucidate the processes missing from the models that cannot capture the link."

Additional References
Catto, J.L., Nicholls, N. and Jakob, C. 2012a. North Australian sea surface temperatures and the El Niño-Southern Oscillation in observations and models. Journal of Climate 25: 5011-5029.