Explainer: El Niño, La Niña, Indian Ocean Dipole: what are the climate patterns that affect Australian weather?

Why does warm water near Peru mean we need to crank up the air conditioner?

El Niño seen via satellite: map of pacific ocean with colours showing sea surface temperature anomaly, central and eastern Pacific is heating up
An El Nino beginning in 2015: sea surface temperature anomalies in the Pacific Ocean, showing heating in the centre and towards the east. Credit: US National Oceanic and Atmospheric Administration