6.4 Drought Flashcards
Causes of drought:
- lack of rain caused by prolonged high pressure: Air in a high-pressure system sinks and doesn’t form
rain clouds. - effect of El Niño Southern Oscillation (ENSO)
and La Niña on ocean temperatures and
evaporation - effect of climate change
effect of El Niño Southern Oscillation (ENSO)
El Niño causes the surface water in the Pacific Ocean
along South America to be warmer.
These warmer waters alter storm patterns and can
cause droughts in Australia.
La Niña on ocean temperatures and
evaporation
Whereas, La Niña causes the temperature of the
water along South America to decrease.
The cooler conditions cause drought in parts of North
and South America.
effect of climate change
- as more green-house gas emissions are released into the air,
- causing air temperatures to increase,
- more moisture evaporates from land and lakes, rivers, and other bodies of water.
- Warmer temperatures also increase evaporation in plant soils, which affects plant life and can reduce rainfall even more.
The impacts of drought:
- death of organisms,
- water sources dry up,
- decline in crop yields,
- starvation,
- Migration from rural to urban areas;
- Unemployment;
- Increase in food prices;
- Health problems due to malnutrition;
- increased soil erosion,
- desertification,
- decrease in air quality,
- increased risk of wildfires
the strategies for
managing the impacts of drought
- monitoring,
- emergency water supplies,
- water conservation like storage tanks, spray irrigation, drought-tolerant crops, water recycling, and reducing deforestation.
- increase water supply (dams and reservoirs, wells, use of aquifers, water transfer, desalination, rainwater harvesting),
- international aid
why are there less deaths in MEDCs from droughts
● greater wealth
● better prediction and emergency planning
● larger stores of food
● better water storage systems
● can afford to import supplies
● greater ability to purify water
● more health facilities to prevent death
