El Nino and La Nina

Question 1

what is a normal year

Answer 1

• cold nutrient rich water flows north along west of S. America (global conveyor belt)
• Upwelling due to winds from the south (offshore winds)
  High producity as it is plankton rich water and it suppports fisheries (economy)
  there is lots of rain in the asia australia side

Question 2

an el nino year

Answer 2

• 3-5 years
• trade winds reduce and may even stop
• large area of wwarm water forms (cold water species may die)
• upwelling significently deacreses and the (nutrient rich cold) water stays locked at the botttom (lack of nutrients at the surface
• primary production rapidly deacreses
• collaps of commercial fish stocks on west and mudslides
• little to no rain in the east cost of pacific and can cause droughts and even stroms

Question 3

an la nina year

Answer 3

immediately follows el nino
- stronger than avarge trade winds
- cold water from Humbooldt current rises and bring nutrients
- greater productivity
- increases hurricans in atlantic Basin