LOS ANGELES, Oct 3 — Sea levels in California are set to rise by as much as a foot (30 centimetres) in the coming days as an enormous wave washes up the US West Coast.

The huge surge of energy, known as a “coastal trapped wave” or a “Kelvin wave,” is part of El Nino, a months-long phenomenon in the Pacific Ocean that scientists say could generate powerful storms and floods in some parts of the world, while leaving others in drought.

The Kelvin wave is not anything like a tsunami; nor does it crash on beaches. Rather it is a sustained bulge of excess water up to 30 kilometres wide that will hug the coastline as it travels all the way up to Alaska.

Dillon Amaya, an oceanographer at North Carolina State University, said the elevated sea levels could collide with other natural phenomena to create problems for coastal communities.