Climate Change in Australia

Figure 10.13: Evidence for Climate Change in the Sahara

Case Study: Climate Change in Australia

  • Overview of Climate Change Effects:

    • Glacial periods in Australia have historically led to:

    • Decreased rainfall.

    • Increased windiness.

    • These climatic changes have triggered several environmental shifts, notably including the formation of wind-driven sand formations.

Historical Episodes of Dune Building

  • Timeframe of Formation:

    • Over the last 370,000 years, at least eight episodes of dune building have been documented.

  • Largest Dune System:

    • The Simpson Desert, recognized as the largest sand dune system in the world.

    • Age: Formed approximately 18,000 years ago.

    • Area: Covers 159,000 km².

  • Characteristics of Simpson Desert Dunes:

    • Consists of linear dunes.

    • Height ranges from 10 to 35 metres.

    • Lengths can reach up to 200 kilometres.

    • Dunes run parallel to each other, with an average spacing of approximately 510 metres.

    • The dunes are primarily fixed (vegetated), with the exception of their crests, which are mobile.

  • Geophysical Processes:

    • The Simpson Desert dunes are part of a continental anticlockwise swirl, associated with the dominant wind patterns of the subtropical anticyclone system.

Area of Continental Sand Dunes

  • General mapping for the area of sand dune systems is essential for understanding geographic distribution.