Background
Climate alarmists typically claim that tropical cyclones -- or TCs -- tend to become both more frequent and more intense as planetary temperatures rise; and as a result, scientists continually strive to develop ever better temporal histories of these particular TC characteristics for various ocean basins around the world.

What was done
Goebbert and Leslie recently examined interannual TC variability of the northwest Australian (NWAUS) sub-basin of the southeastern Indian Ocean (0-35°S, 105°-135°E) over the 39-year time period of 1970-2008, using the Woodside Petroleum Ltd. reanalysis TC dataset described by Harper et al. (2008), in order to focus on these two important TC characteristics (frequency and intensity), as well as eleven other TC metrics.

What was learned
The two researchers report they could find "no significant linear trends in either mean annual TC frequencies or TC days," and they say there was also "no trend in the number of intense TCs for the NWAUS sub-basin." In fact, they state that "none of the 13 NWAUS TC metrics exhibited statistically significant linear trends." And they add that "known climate indices -- such as Niņo-3.4, Niņo-4, SOI, NOI, PDO, NAO, and others -- generally were found not to be significantly correlated to the variability of TC frequency or TC days in the NWAUS region."

What it means
Once again we have a situation where climate-alarmist theoretical contentions are not supported by real-world data.

Reference
Harper, B.A., Stroud, S.A., McCormack, M. and West, S. 2008. A review of historical tropical cyclone intensity in northwestern Australia and implications for climate change trend analysis. Australian Meteorological Magazine 57: 121-141.