Drought causes and locations (Edexcel GCSE Geography A): Flashcards
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Practise the cards
12 cards from this deck
Arid vs drought conditions
Arid vs drought conditions
Arid=permanently dry; drought=temporarily dry conditions
What causes arid regions?
What causes arid regions?
High atmospheric pressure systems prevent clouds & rainfall
Annual precipitation in arid regions (mm)
Annual precipitation in arid regions (mm)
10-250mm
UK drought definition
UK drought definition
15 consecutive days without rainfall
What is meteorological drought?
What is meteorological drought?
Region receives less precipitation than long-term average
Cause of meteorological drought
Cause of meteorological drought
High pressure systems established over area for long periods
What is hydrological drought?
What is hydrological drought?
Water cycle receives less input, affecting groundwater & rivers
Drought feedback loop process
Drought feedback loop process
Drier land→less moisture→less future rainfall
Global circulation & drought vulnerability
Global circulation & drought vulnerability
Hadley & Ferrel cells create descending dry air zones
How deforestation contributes to drought
How deforestation contributes to drought
Reduces transpiration & atmospheric moisture locally
How dams contribute to drought
How dams contribute to drought
Restrict water flow, reducing volume downstream & groundwater
Role of trees in water cycle
Role of trees in water cycle
Transpiration releases water vapour; roots store & release water