The alpine areas of NSW and ACT are particularly vulnerable to climate change. Regional climate projections show that the region is likely to experience higher temperatures, fewer cold nights, and lower rainfall, highlighting that climate change may significantly impact natural systems and communities in the region.

Projections of future changes are investigated for both the near future (2020 to 2039) and far future (2060 to 2079) relative to a baseline (1990 to 2009).

The study area for the Alpine project, including the NSW and ACT alpine region, Murray-Murrumbidgee region and South East and Tablelands.

Projected climate

Observations have shown substantial changes in precipitation and temperature, which are impacting ecosystems in the region. Among the projected changes for the alpine region are:

• Winter temperatures more than 3°C warmer are projected for the far future.
• Reduced annual rainfall in the far future, mostly due to a 20 per cent decrease in spring.
• Further detail is available in Climate change impacts in the NSW and ACT Alpine region: Projected climate.

Fire weather

While bushfires are a natural phenomenon in Australia, they can cause significant damage and loss to human life and infrastructure. Projected changes in the fire weather in the alpine region include:

• Forest Fire Danger Index (FFDI) in winter and spring projected to increase by 30 per cent, with an annual increase of 5–10 per cent predicted across all seasons.
• An increase of up to 3 extreme fire weather days in the far future is projected for the western Murray-Murrumbidgee region.
• Further detail is available in Climate change impacts in the NSW and ACT Alpine region: Impacts on fire weather.

Changes in annual extreme FFDI days for 2060 to 2079 relative to 1990 to 2009.

Water availability

Climate change can impact water availability, quality, salinity and aquatic biodiversity. Projected affects to water availability through changes in surface runoff and recharge to groundwater in the alpine region are:

• In the near future, most of the region is likely to have less surface runoff, while the west of the Murray-Murrumbidgee region is likely to experience increased surface runoff.
• In the far future, reductions in surface runoff of more than 40 millimetres per year are projected for higher alpine areas.
• Further detail is available in Climate change impacts in the NSW and ACT Alpine region: Impacts on water availability.

Changes in mean annual recharge (mm) in the NSW and ACT alpine region for 2060 to 2079 relative to the 1990 to 2009 baseline period.

Snowmaking conditions

The NSW and ACT alpine region is a popular winter holiday destination with ski resorts located across the region. Climate change is projected to affect the snow depth and artificial snowmaking conditions with:

• Large decrease in suitable temperatures for artificial snowmaking projected in the near (20 per cent) and far future (60 per cent), with lower elevations potentially unsuitable for making snow.
• Further detail is available in Climate change impacts in the NSW and ACT Alpine region: Projected changes in snowmaking conditions.

Monthly suitable snowmaking time for ski resorts using the current -2°C threshold for making snow for 1990 to 2009 (solid lines), 2020 to 2039 (dashed lines) and 2060 to 2079 (dotted lines).

Crop suitability

Climate change has direct impacts on crop productivity that might present challenges to food security worldwide. This report presents the impacts of climate change on certain crops in the downstream Riverina-Murray region. Understanding the regional impacts of climate change on crop yields is essential to develop key adaptive strategies and mitigate negative impacts on food security. The main projected impacts include:

• Crop yield to slightly increase in the near future and substantially increase in the far future largely due to an improvement in the simulation of growing season rainfall.
• Further detail is available in Climate change impacts in the NSW and ACT Alpine region: Impacts on crop suitability.

Soil erosivity and hillslope erosion

Climate change is expected to impact soils through changes in soil erosion, which can have significant implications for natural assets, agricultural lands and water quality. The projected changes in climate are expected to:

• Increase soil erosivity and hillslope erosion by 2-8 per cent in the near future, and 8-18 per cent in the far future, even if the groundcover is maintained at the current level.
• Increase summer time erosion risk by about 25 per cent in the next 20 to 50 years.
• Further detail is available in Climate change impacts in the NSW and ACT Alpine region: Impacts of extreme rainfall on soil erosivity and hillslope erosion.

Biodiversity

The NSW and ACT alpine region hosts unique biodiversity. Plants and animals in the region have evolved to fit a small window of suitable environmental conditions, making them sensitive to changes in the climate. Some of the projected climate changed impacts on biodiversity are:

• A 21-70 per cent change in the species composition of vegetation communities in the far future.
• Plants currently listed as critically endangered, including the Kelton's Leek Orchid (Prasophyllum keltonii), will be under increasing pressure as climate change proceeds.
• Further detail is available in Climate change impacts in the NSW and ACT Alpine region: Impacts on biodiversity.

Kelton's Leek Orchid, Prasophyllum keltonii, photo Geoff Robertson.

Integrated assessment using the MCAS-S tool

Adapting to climate changing impacts can be technically and socially complex, requiring the integration of information including: bio-physical (e.g. ecology, soils, hydrology), cultural, economic (e.g. farm profitability, commodity prices) and social (e.g. wellbeing, behaviour). The datasets generated by this project have been incorporated into a datapack for the alpine region that allow exploration by the user. The Multi-Criteria Analysis Shell for Spatial Decision Support (MCAS-S) software was applied to facilitate the integration of different types of spatial data in the NSW and ACT alpine region.

• Further detail is available in Climate change impacts in the NSW and ACT Alpine region: Integrated assessment using the Multi-Criteria Analysis Shell for Spatial Decision Support (MCAS-S) tool.
• Download datasets from the SEED Portal.

About the project

Climate information from the NSW and ACT Regional Climate Modelling (NARCliM) Project was used to investigate the biophysical and social impacts of climate change on the NSW and ACT alpine region. This is the first time NARCliM data has been used to assess changes in climate impacts in the Australian alps (NSW, Victoria and ACT).

This project has been managed by The Department with external research partners, University of New England, University of Technology Sydney and the Department of Primary Industry. For more information contact climate.research@environment.nsw.gov.au