9GEO1: Lesson 2.2 - The Big Dry Flashcards Preview

9GEO1 - LGS Physical Geography > 9GEO1: Lesson 2.2 - The Big Dry > Flashcards

Flashcards in 9GEO1: Lesson 2.2 - The Big Dry Deck (8)
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1
Q

What is the name of the river basin that constitutes Australia’s agricultural heartland?

A

Murray-Darling Basin (its one of the flattest catchments on Earth)

2
Q

How much water is available for human use?

A

Not much (32,500 GL per year on average) – as 94% of rainfall evaporates from waterways / floodplains

3
Q

Climate modelling could ONLY reproduce the strengthening of Australia’s ‘high pressure’ related drought conditions when what factor was included?

A

Anthropogenic warming due to greenhouse gases – it is thought that they reduce the temperature gradient between the Equator and Poles (reducing energy for mid-latitude storms)

4
Q

How many people depend on the Murray-Darling basin’s water?

A

3.5 million

5
Q

How much surface water is removed from the river system and how?

A

42% – either pumped directly from the river to a property or diverted into an irrigation system for urban or agricultural use

6
Q

What was put in place in response to declining river health?

A

A cap on diversion of water from basin’s river system (by Murray-Darling Ministerial Council)

7
Q

Which human activity is thought to have greatly intensified and prolonged the period of drought over SE Australia?

A

Land clearance - removal of over 90% of original vegetation since 1800s is thought to contribute to the increased length of drought in any given year.

8
Q

Why has the water diversion cap and subsequent Murray-Darling Basin Plan caused more problems?

A

It has caused tensions between irrigation-dependent communities, as many illegally extract way above their quota - leaving households downstream particularly vulnerable!