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Title: Fifteen Years of (Major to Great) Tsunamigenic Earthquakes
Tsunamis are a series of long gravity waves generated by abrupt displacement of a significant volume of water that propagate under the action of gravity, returning the water layer to an equilibrium position. Differently from common wind-generated waves, tsunamis are characterized by large wavelengths (ranging from tens to hundreds of km) and long periods (ranging from minutes to hours) with water motions extending across the entire depth range of the water layer. Several natural phenomena such as earthquakes, landslides, volcanic eruptions, rapid changes of atmospheric pressure (meteotsunami), or asteroids impacts can be the source of the initial water displacement of a tsunami; among these, the most frequent involves submarine earthquakes. Most tsunamigenic earthquakes occur near Earth’s convergent plate tectonic boundaries (Fig. 1), at subduction zones, where an oceanic plate underthrusts another plate. During the last 15 years (2004-2019), subduction zones hosted a particularly high number of great magnitude tsunamigenic earthquakes with catastrophic consequences in terms of casualties and damages. This spate of activity is consistent with normal statistical fluctuations of seismicity rate over the past century (Lay, 2015), however, the collective tsunami impact was particularly severe in terms of fatalities, people missing, building destruction, and damage to infrastructures (e.g., ports, power plants, coastal towns). The largest tsunamis since 2004 were those ensuing from the 2004 Mw 9.2 Sumatra-Andaman (Indonesia) and the 2011 Mw 9.0 Tohoku (Japan) earthquakes (e.g., Lorito et al., 2016), causing 220,000+ and 15,000+ victims, respectively.  more » « less
Award ID(s):
1802364
PAR ID:
10145646
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Earth systems and environment
ISSN:
2509-9434
Page Range / eLocation ID:
1-13
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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