Main cause of La Niña:La Niña happens when Pacific Ocean surface waters become colder than normal due to stronger-than-usual trade winds.These winds push warm water toward Asia, letting cold water from the deep ocean rise to the surface near the Americas.How to prevent it:La Niña is a natural climate pattern — humans cannot prevent it.What we can do is lessen its effects: Prepare early warning systems for floods and storms.Strengthen riverbanks and drainage systems.Store food and emergency supplies in affected areas.Educate communities about disaster safety plans.