An Update of the Hs Values for Queensland, Australia to Comply with Australian Standard AS 2870-2011

Prior to this paper, the most recent work on TMI/Hs for Queensland was published by Fox in 2002. The Thornthwaite moisture index (TMI) was taken over a minimum of twenty years and this 2002 work generally complied with this principle. When AS2870 was revised in 2011, with respect to the TMI, they asked that it be calculated over a minimum period of 25 years, and at the same time gave a new relationship between the TMI and the Hs. The net result of these changes in AS2870 was that some of the 2002 data points were inside the 25 years time window and the changes in relationship between TMI/Hs meant that existing maps were no longer relevant for use by practitioners. This paper was commissioned to provide consistency for practitioners, using up-to-date data, as well as utilising advances in technology (e.g., Google Earth) to enable the practitioner to determine the Hs for a particular geographical area of the state of Queensland.