Final answer:
El Niño is the weather system that could be occurring if Australia is experiencing droughts and parts of South America are flooded.
Step-by-step explanation:
A weather system that could be occurring if Australia is experiencing droughts and parts of South America are flooded is El Niño. El Niño is a climate phenomena that occurs in the Pacific Ocean and can have far-reaching effects on global weather patterns. During an El Niño event, the warm ocean currents in the eastern Pacific Ocean disrupt normal atmospheric circulation, leading to changes in rainfall patterns.
Learn more about El Niño