Droughts Flashcards
1
Q
Aridity
A
a perennial state of water shortage
2
Q
Drought
A
a sustained and regionally extensive occurrence of below average water availability
3
Q
What drives drought?
A
- weather
- catchment characteristics
- human drivers
4
Q
Weather impact
A
- lack of precipitation
- surplus of evaporation
- reduced snowpack
- anticyclone: sinking air mass, persistence due to blocking pattern
- positive feedback of soil moisture (high temps, increased evap, higher temps)
5
Q
Catchment characteristics impact
A
- geology (rock type, soil type)
- geomorphology (slope)
- land use and land cover
6
Q
Human drivers
A
- farming (excessive irrigation)
- deforestation
- erosion
7
Q
Drought categorisation
A
- meteorological: atmospheric demand
- hydrological: availability for runoff
- agricultural: plant demand
8
Q
Standardised precipitation indices
A
a deficit of precipitation impacts on soil moisture, steam flow, reservoir storage and ground water level etc. on different time scales
9
Q
Human causes of vegetation change
A
- overgrazing
- collection of fuelwood
- positive feedback
- bad agricultural practices
10
Q
Climate changes
A
- ocean temperatures changes
- reduced monsoon intensity
- shift in ITCZ
11
Q
Impacts of drought on the environment
A
- increased fire risk to: blanket bog, upland and lowland heaths
- abstraction for agriculture can worsen effects
- negative effects on habitats: implications for species
12
Q
What can we do against drought?
A
- education of population
- good and sustainable agricultural practices
- reduce erosion and soil degradation
- improve forecasting and monitoring
- integration of science into policy
