What are the projected climate change impacts for Tasmania?

The Climate Futures for Tasmania project found that the following projected changes are likely by 2100. The projections are based on two of the emissions scenarios set by the Intergovernmental Panel on Climate Change

Projected changes to Tasmania’s climate

Temperature

• Average temperatures will continue to rise. Tasmanian temperatures are projected to rise by about 2.9° Celsius under the high emissions scenario, and about 1.6° Celsius under the low emissions scenario.
• Temperature increases in Tasmania are less than the projected global average temperature rise, due to the moderating influence of the Southern Ocean.

Rainfall

• There is no significant projected change to total statewide annual rainfall.
• However, significant changes are projected in the regional and seasonal pattern of rainfall across the State:
  • The West Coast is projected to experience a significant increase in rainfall in winter; and a significant decrease in rainfall in summer after 2050.
  • The central plateau district is projected to experience a steady decrease in rainfall in every season out to 2100.
  • The North-East Coast is projected to experience a steady increase in autumn and summer rainfall.
• Significant increase in pan evaporation.

Wind

• Increase in average wind speed across the State.

Runoff

• Runoff is excess water from rain or snow melt, flowing over land.
• Runoff is affected by changes to both rainfall and evapotransipiration (where water lost from the land surface is both evaporated and transpired by plants). By 2100 it is projected that there will be a slight increase in the State's total amount of runoff.
• However, runoff is projected to decrease markedly in Tasmania's central highlands, and increase in the important agricultural regions of the Derwent Valley and the Midlands.

Frost

• By 2100, it is projected that the incidence of frost will reduce by about half.
• For many areas of Tasmania, the period of frost risk is also projected to shorten from March-December (10 months) to May-October (6 months).

Marine impacts

• Mean sea level will continue to rise. For Tasmania, this is predicted to be between 0.39 and 0.89 metres by 2090.
• Increase in mean statewide sea surface temperature (SST) in all seasons by the end of the century.
• Greater increase in SST in the east and north-east than other regions, due to the southward extension of the East Australian Current.
• An increase in ocean acidification levels and East Coast water temperature by up to 2-3 degrees Celsius by 2070 (relative to 1990 levels).

Extreme events

• Increased frequency and intensity of storm events.
• Increased instances of coastal erosion and coastal inundation.
• Longer fire seasons and more days at the highest range of fire danger.
• More hot summer days and more heatwaves.
• Drought in some parts of the State.
• River flooding in some catchments.

Findings of the latest IPCC Report

The Intergovernmental Panel on Climate Change (IPCC) Climate Change 2022: Impacts, Adaptation and Vulnerability includes a number of references to observed and projected impacts for Tasmania, including:

• Observed loss of 90 per cent of giant kelp in Tasmania by 2011 due to warming and extension of the East Australian Current.
• Projected loss of kelp forests in southern Australia due to ocean warming, marine heatwaves and overgrazing by climate-driven range extensions of herbivore fish and sea urchins.
• Projected transition to a new ecosystem state, or collapse, of the pencil pine (Athrotaxis cupressoides), a fire-sensitive tree that is endemic to Tasmania, due to hotter and drier conditions with more fires.
• Projected increasing threats to temperate montane rainforest in Tasmania, due to increases in heat and wildfires.
• Loss of alpine biodiversity in Australia due to less snow.
• Projected improved growing conditions for some crops and land uses, including: plantation forest growth; wine production; and wheat crops.
• Opportunities for new wind energy installations due to projected increase in wind speed.

What we have seen

Australia’s climate has already warmed on average by 1.44^°C since 1910, with most of the warming recorded since 1950. Australia’s warmest year on record was 2019, and in 2020 Tasmania had warmer nights than usual for much of the year, especially in the North-East. 2019 was also Australia’s driest year on record, with annual rainfall 40 per cent below average, and much of Australia affected by drought. Learn more about the Australian projections in the CSIRO and Bureau of Meteorology State of the Climate 2020 Report.

In recent years, Tasmania has experienced two significant bushfire events, a record marine heatwave off the East Coast, prolonged dry periods in 2015-16 and 2019-20, and flooding.

These events have had an environmental, economic and social impact on governments, businesses, communities and households.

What do we do with our knowledge?

The Tasmanian Government is working with communities, businesses and households to reduce the risks associated with these projected changes in our climate, and to minimise the potential for damage to our environment, assets and infrastructure.

Changes to the climate may also present opportunities for Tasmania. For example, because Tasmania’s climate is milder than other Australian states, the impacts of climate change in many cases will be more moderate. This could be beneficial for the agriculture, aquaculture and viticulture industries. A milder climate may also increase Tasmania’s standing as a tourism destination and potentially increase immigration, helping to deliver a stable and sustainable population that supports local economic growth