Haiyan gave momentum to most massive rock ever seen moved by a storm
SAN FRANCISCO — When Typhoon Haiyan made landfall in the Philippines in November 2013, its waves shoved a boulder weighing more than 25 adult African elephants. The boulder is the most massive known rock shifted by a storm, geoscientist Max Engel of the University of Cologne in Germany reported December 16 at the American Geophysical Union’s fall meeting.
Engel and colleagues initially thought there was a language barrier when a local fisherman told them that the 9-meter-wide, 180-metric-ton rock moved during the storm. Comparing satellite photos taken before and after the storm, the researchers found that the boulder traveled about 45 meters along a beach.
Based on videos recorded during the storm, the researchers think the typhoon created protracted tsunami-like waves that pushed the hefty rock. The observations suggest that other boulder movements that scientists had associated with tsunamis might actually have been caused by superstorms, Engel said.
M. Engel et al. Storm surge of Supertyphoon Haiyan (7–9 Nov 2013) on Samar (Philippines) moved the largest boulder ever documented for a recent storm. American Geophysical Union annual fall meeting, San Francisco, December 16, 2014.