Remembered for his skill, versatility, and excellent sportsmanship as a surfer, he rose to international fame in his teens for a surfing feat at Mavericks (in Northern California) and a subsequent Surfer magazine cover shoot. Tragically, he died in his early twenties as the result of a diving accident.
He started surfing before his tenth birthday and quickly became proficient on both shortboard and longboard.
The year he died, Moriarity co-wrote a manual titled The Ultimate Guide to Surfing.
He spent his earliest days in Georgia and the bulk of his childhood in Santa Cruz, California.
He was the subject of a 2012, Curtis Hanson-directed film titled Chasing Mavericks.