El Nino & La Nina Flashcards
Describe the trade winds during the La Niña period.
- Very strong
- East to West direction
Describe the trade winds during the El Niño period.
- Weak
- West to East
What hazard is linked to El Niño in Eastern Australia?
Drought
What hazard is linked to El Niño in western South America?
Flooding
What causes drought?
Descending air which creates high air pressure and a lack of rain.
What causes flooding?
Low air pressure and warm air rising which cools and condenses into rain.
Which event is the extreme version of a normal year?
La Niña
During which event do the trade winds change direction?
El Niño
Why is the fishing season improved during the El Niño period?
Upwelling of warm water in the East causes nutrients to rise to the surface, attracting fish.
What are the timescales of La Niña and El Niño?
Lasts 1-2 years and occur every 3-7 years.
What did El Niño cause in Northern California in January 1997?
Flooding
What altitude was the rainfall which caused snow melt?
11,000 feet
How much was the economic damage caused by the 1997 flooding in California?
$2bn
How many homes were affected by the 1997 flooding in California?
23,000
How much land was flooded in California 1997?
300 square miles
