Just five years ago, there would have been no midocean tsunami buoys between Chile and Hawaii, and forecasters would have been left guessing at the size of the waves until they hit.
This time, there was a buoy several hundred miles off Peru that recorded the tsunami as it sped by at more than 400 miles per hour, three hours after the earthquake.
“For this case, we had to pretty much base our forecast on one dot, because of the timing,” said Vasily V. Titov, a researcher at the Pacific Marine Environmental Laboratory in Seattle who developed one of the three models used by the warning center. In 2004, there were six tsunami buoys. Now there are 39.
The data from the one buoy was enough for the computer model to figure out that the tsunami was smaller and less destructive. At 6:24 a.m. Saturday in Hawaii, about five hours before the arrival of the tsunami there, the tsunami center put out a bulletin with predictions that the wave might reach four feet at Hilo, where the bay tends to amplify the waves, and much lower elsewhere.
That’s a heckuva dot.