New research ties a looming Cascadia quake to 1,000\u2011foot waves that might redraw America\u2019s Pacific shoreline.<\/p>\n\n\n\n
The prospect of a \u201cmega tsunami\u201d once confined to disaster movies now sits on scientists\u2019 short\u2011term radar. A Virginia\u202fTech team reports that a powerful earthquake along the Cascadia subduction zone\u2014stretching from northern Vancouver Island to California\u2019s Cape\u202fMendocino\u2014has about a 15\u202fpercent chance of striking within 50\u202fyears. Add rising sea levels and the result could be walls of water tall enough to erase entire coastal neighborhoods.<\/p>\n\n\n\n
First things first: why is Cascadia such a big deal? The fault is locked and building stress. When it slips, coastal land could drop as much as 6\u00bd\u202ffeet before the first wave even arrives. Northern California, northern\u202fOregon and southern\u202fWashington would feel the brunt, but the shock would reverberate across the Pacific. \u201cThe expanded floodplain would slow recovery for years,\u201d warns lead author Tina\u202fDura.<\/p>\n\n\n\n
Who should pay closest attention? Coastal homeowners, port managers and anyone mapping new housing developments near low\u2011lying inlets.<\/p>\n\n\n\n
Cascadia isn\u2019t alone on the worry list. Alaska\u2019s steep, glacially scarred fjords keep shedding rock as permafrost thaws, increasing slide\u2011generated waves. Meanwhile, Hawaii\u2019s volcanic flanks have a long history of collapsing into the sea\u2014Lanai was struck by a 1,000\u2011ft surge roughly 105,000\u202fyears ago. With Mauna\u202fLoa and Kilauea still active, scientists say a similar event, though rare, remains on the table. Scary, right? The snapshot below highlights the distinct hazards across the three regions.<\/p>\n\n\n\n