| Environment
An important consequence of the extent of the Murray-Darling Basin is the range of differing natural environments. From cool, humid rainforests, inland sub-tropical areas and temperate mallee country to the hot, dry semi-arid and arid lands.
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| Each of these environments contain unique species and landforms that together characterise the Murray-Darling Basin. What can seem as relatively minor changes can have dramatic implications and as a result, many of these environments have been altered.
The following sections further detail the different environments of the Murray-Darling Basin. Climate Change Climate Change is currently a major issue facing the Basin.
What is the Greenhouse effect?
The greenhouse effect is a natural phenomenon where greenhouse gases in the atmosphere - principally carbon dioxide (CO2 ) , methane and nitrous oxide trap heat from the earth’s surface to regulate temperatures. Without this natural effect we would be living in a very chilly place; the world's average temperature would be -18°C, instead of the +16°C we are accustomed to. Australia warmed by an average of 0.7°C from 1910-1999. Scientists expect further global warming and regional climate change if greenhouse gas levels continue to increase in the atmosphere. CSIRO scientists have indicated that projected emissions of greenhouse gases from human activities are likely to result in the following climate changes:
• Increased temperature: Around 1 to 5°C increase in temperature is predicted by 2070.
• More extreme hot days: Number of days above 35°C is expected to increase from the current average of 10 days per year to somewhere between 13 and 28 days per year by 2070.
• Less rainfall and more evaporation: The likely scenario is for less rainfall. Models predict a change of rainfall between +10% and –35% by 2070. Even if rainfall does increase, higher evaporation rates, produced by increased temperatures will mean that in all scenarios, there will be a net water balance deficit.
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