The CSIRO report involves one possible scenario based on specific modelling. Possible climate variability due to different emission scenario assumptions and models used are areas for future work. It predicts that while the overall impact of climate change on Tasmania is expected to be relatively moderate up to 2040, there could be seasonal changes to rainfall with an increase in rainfall of between 7-11% in all catchments except for the South Esk, where rainfall is expected to decrease by around 8%.

The report also suggests that there will be a small increase in Tasmania’s minimum temperatures of around 1° and a smaller rise in maximum temperatures over the same period.

The report was commissioned to assist in the long-term management of the State’s hydro storages. As well as the CSIRO, the University of Tasmania and the Tasmanian Partnership for Advanced Computing were also involved in preparing the report.

The four-stage process undertaken to develop the report’s findings included a general assessment of climate outlook from existing information, the calibration of information from a high level regional model of observed data and projections of Tasmanian climate to 2040.

Dr Mike Connarty, Manager of Energy and Market Analysis at Hydro Tasmania, said it was important to model possible scenarios relating to rainfall and other climate indicators that could impact on the State’s water storages to enable planning for future energy requirements.

‘The important thing to emphasise from the start is that this is one possible scenario based on specific modelling rather than a detailed variable forecast of climate change,’ Dr Connarty said. ‘However, it is a valuable exercise to enable us to do some long-term planning.

Connarty said that overall it appears that Hydro Tasmania won’t experience significant changes over the next 35 years because of Tasmania’s geographic location where the climate is moderated to a large extent by the surrounding ocean.

‘While the report suggests the impact of climate change on Tasmania is expected to be moderate, changes in seasonal rainfall could require adjusting Hydro Tasmania’s generating operations,’ he said. ‘We are currently assessing the impacts on the system from the report’s findings and what potential operational changes will need to be made. If this assessment indicates a significant impact on our business, a further report may be commissioned to assess possible variability of climate change.’

The report also modelled possible changes to evaporation, wind speeds and direction.

A synopsis of the report is now available on Hydro Tasmania’s website by clicking on the weblink below.

External weblinks

Hydro Tasmania