Increasing Wave Heights along the Shores of the United States: Climate Controls and Hazards

Progressive increases in storm intensities and the heights of their generated waves have occurred along the Atlantic and Pacific shores of the United States, spanning at least the past 35 years. Those increases include the waves generated by hurricanes in the Atlantic and extratropical storms in the northeast Pacific. The increases in hurricane intensities and waves can be attributed to global warming, the elevated water temperatures being the "fuel engine" of tropical cyclones. The extratropical storms also appear to be intensified by global warming, but are significantly affected by climate cycles such as the range from El Niños to La Niñas. It is important to account for these climate controls in models directed toward coastal-hazard assessments, so that future changes in storm intensities and wave heights are included, in addition to the projected accelerated rates of sea-level rise.