El Niño is a natural phenomena where warming of the Pacific Ocean occurs as a result of trade winds which weaken causing warm water to move closer to the coast of South America. This results in disruption in the environments affected such as increased rainfall, flooding, droughts, and an overall reduction in marine life! A key factor in El Niño is the Thermocline (layer between warmner surface water and colder deep water) getting deeper, causing nutrient rich waters on the coast to be depleted by the warmer waters! This occurs usually around Christmas and last 3-7 months or up to a few years!
La Niña is a phenomena which is the opposite of El Niño, and effectively corrects it creating "normal" conditions. Sea and surface temperatures fall, and this usually lasts 9-12 months and up to 2 years!
A warm front occurs when a warm air mass pushes up and over a cold air mass. Warmer air replaces colder air.
A cold front occurs when a cold air mass pushes into a warm air mass. Colder air replaces warmer air.
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