A LOW is a meteorological phenomenon characterized by a large area of LOW atmospheric pressure. A moonbow is a meteorological phenomenon that occurs when the moon's light is reflected and refracted off water droplets in the atmosphere, creating a rainbow-like effect. El Niño and La Niña are meteorological phenomena that involve changes in ocean temperatures in the Pacific Ocean. Aurora Australis is a meteorological phenomenon that involves the display of colorful lights in the night sky, usually seen in the southern hemisphere.