The 2004 tsunami off Sumatra’s coast is one of the greatest natural disasters of our time, claiming hundreds of thousands of lives and ravaging nations in its wake. But nobody expected a tsunami. In fact they are quite uncommon in the Indian Ocean, the last one taking place in 1883. It was collective unpreparedness that led to widespread devastation when the unlikely earthquake ultimately struck. But obscured from view amidst a wooded cliff, a cave was recently discovered that researchers think will provide unprecedented tsunami insight specific to that region.
The cave’s overgrown limestone entrance hugs the side of a cliff, denying entry to virtually anyone and anything, except bats and tsunami-sized wave surges. The bats have left their droppings, and plenty of them. But between the layers of guano lie undisturbed layers of sandy deposits washed in by tsunami surges. Ten sediment layers provide an impeccable record of past Indian Ocean tsunami’s dating back 7,500 years. Due to the cave’s elevated entry point, the 10 tsunami’s that generated these deposit layers would have been magnitude 8 or higher, the most recent one in 2004 measuring in at 9.2.
By analyzing the clues left in nature’s past, we can better secure our future. But preparations will only protect us to a point. Nature’s brutal force paired with its randomness is the universe’s ultimate foe, trumping man simply on his best day. To live on this planet, one must live to expect the unexpected.