During which months does the el niño end and the la niña begin?

The tropical Pacific Ocean and atmosphere swings, or oscillates, between warm, cool and neutral phases on a timescale of a few years. A typical El Niño or La Niña event may show its first signs of development during the southern hemisphere autumn and strengthen over winter and spring.

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alisa202

Answer volcanic eruptionsseismic waves from earthquakes;

Either b or c . i did this before