Tropical cyclones and associated flooding are the most devastating meteorological phenomena in tropical regions; thus an improved understanding of the past trends in tropical cyclone occurrences, and a better understanding of the relationship with El Niño Southern Oscillation (ENSO) in the central Southwest Pacific region (South of equator, 140E to 170E) would be of great value for future adaptation.

For the 1969/70 to 2012/13 tropical cyclone seasons, there is no statistically significant trend in the total number of cyclones in the central southwest Pacific. There is also no trend in the number of severe cyclones (TCs < 970hPa) for the 1980/81 to 2012/13 period. In the central Southwest Pacific, more cyclones affect the island communities in an El Niño year as compared to a neutral or La Nina years, however, we find that there are weak correlations with ENSO and agree with previous work that it is not sensible to further develop linear regression models for tropical cyclone prediction for this region. Based on this result, we support the development of dynamical prediction methods which are better at incorporating the effects of a changing climate, whatever its character or cause.

An enhanced understanding of past trends in tropical cyclone occurrences, its existence during different ENSO phases, intensity and the development of dynamical prediction methods will assist communities, policy and decision makers to make informed decisions in the future.