A new study by Oregon State University and the Oregon Department of Geology and Mineral Industries is calling attention to the fact that the biggest waves hitting the Pacific Northwest are now significantly larger than they were only a few decades ago. The increase is most dramatic in the far north and, so far anyway, barely detectable in Central California.
Whether the increased wave heights are being caused by global warming (likely) or by some unrelated change in ocean dynamics (possible), bigger waves are certain to accelerate coastal erosion rates and cause damage to coastal development far beyond what is expected from rising sea levels.
Meanwhile, back on the Central Coast, the moderately large waves generated by the past week of storms are putting on an excellent demonstration of how coastal erosion works.
The process begins as waves remove the barriers of sand (i.e. the beaches) that normally protect the most vulnerable parts of the coast from the surf, bringing the ocean, even at low tide, right to the bottom of easily erodible bluffs.
The Carmel Beach at the bottom of 13th Avenue a few months ago
The same spot today
Until gentler surf replaces the sand, serious erosion is certain to continue. Already, waves have undermined Highway One along the South Coast and Scenic Rd. in Carmel.
With most of the beach gone, the sand dune supporting Scenic Rd. was exposed to the full force of the surf
County crews work at low tide to shore up the crumbling road by piling boulders and backfilling with sand
But until a decent beach rebuilds, the road will remain at the mercy of the ocean