Climate change in Victoria
Our climate is changing. Over the course of the 20th century, the average global temperature has increased by 0.6°C - making it the warmest in the last 1,800 years. In Victoria, 2007 was the hottest year on record.
Climate change modelling
The Victorian Government supports the work of CSIRO in developing regional climate change projections for Victoria.
CSIRO's projections are based on the results of climate modelling experiments, in which the effect of increased levels of greenhouse gases in the atmosphere is simulated. Information is provided in a range to allow for uncertainty in the future growth in greenhouse emissions, and for differences between the simulated climate change of various climate models.
Regional climate change projections for Victoria - 2008 figures
In 2004, the Victorian Government released regional climate change projection brochures for Victoria's 10 Catchment Management regions.
These brochures have now been updated for 2008 and can be accessed on the left hand column of this web page. The 2008 State Summary for Victoria can be accessed here.
DSE Climate Change State Projections Summary (PDF - 1.6 MB)
Observed changes in Victoria's climate
Victoria's climate is already changing. Both maximum and minimum temperatures have increased by 0.8 degrees celsius since 1950. At the same time, Victoria has experienced a decline in total rainfall of 13%.
The incidence of severe droughts during strong El Niño events has tended to be more frequent, and it is believed that the impacts of the 2002 drought are likely to have been enhanced by climate change.
Victoria's future climate
CSIRO and the Bureau of Meteorology published climate change projections for Australia in October 2007. Climate Change in Australia provides the latest information on observed climate change over Australia and its likely causes, as well as updated projections of changes in temperature, rainfall and other aspects of climate that can be expected over coming decades as a result of continued global emissions of greenhouse gases. Results for Victoria indicate that:
- Average temperatures will increase by around 0.8°C by 2030, with a range of 0.6-1.2°C. By 2070 this increase is projected to be around 1.4°C (range of 0.9-2.0°C) under a low emissions scenario or around 2.7°C (range of 1.8-3.8°C) under a high emissions scenario.
- The chance of at least a 1°C warming in 2030 is around 20-30%. This rises to 80-90% for the 2070 low emission scenario and over 90% for the 2070 high emission scenario. There is a 1-10% chance of a 2°C warming for the 2070 low emission case and 80-90% for the 2070 high emission case.
- As per previous projections, annual, winter and spring rainfall is likely to decrease, whereas changes in summer and autumn rainfall are less certain. By 2030 annual rainfall is projected to decrease by around 4% (range of -9 to 1%) relative to the climate of the past century. By 2070 the change is projected to be a decrease of 6% (with a range of -14 to 2%) under a low emission scenario, or 11% (with a range of -25 to 3%) under a high emission scenario. On the other hand, rainfall intensity is most likely to increase in summer and autumn. .
- The chance of an annual average decrease of at least 10% increases over time. There is a 1 to 10% chance by 2030, 20-30% by 2070 for the low emission case, and 50-60% by 2070 for the high emission case.
In addition to these changes, Victoria is likely to have increasing evaporation rates, increased days of high fire danger, much less snowfall, more frequent drought and greater risk of coastal erosion and inundation.
The Intergovernmental Panel on Climate Change (IPCC) projects a sea level rise of 18 to 79cm by 2095, relative to 1990.
