Thanks to El Niño, Hawaii's waves are not only spectacularly large, but also very good at uncovering lost ancient rock art. (The waves are also spectacularly dangerous, as one surfer recently experienced.)

Last week at Pine Tree Beach on the Big Island's Kona Coast, locals walking the shore were treated to an extremely rare appearance of several petroglyphs. Normally covered by over 10 feet of sand, the rock art was ever-so-briefly revealed by the pounding surf.

"They're a really special thing to see, but they disappear really fast," resident Avi Salvio told Hawaiian News Now.

The ancient art, featuring depictions of people and dogs, is estimated to be several hundred years old. Archeologists would love to study them further, but nature is less than willing to cooperate. Only 24 hours later, the petroglyphs were once more buried under sand and water.

"As you're watching during the day the sand will cover them up and you try to sweep the sand off of them so they'll stay up a little longer," Salvio added.

It's believed that some 70 ancient petroglyphs lie buried along the shore at Pine Tree. The images, thought to be records of births and other significant events in the lives of Native Hawaiians, are found in the tens of thousands throughout the island chain. The video below offers a fascinating overview: