'Most stressful winter': El Nino-fueled coastal erosion in California likely to get worse

El Nino and a very active Pacific hurricane season are bringing significant coastal erosion to the Southern California coastline, with experts warning it could get even worse this winter.

The erosion has already affected private residences, parks, beaches and roadways across the region, bringing the Pacific Ocean surf dangerously close to infrastructure.

“We need to be in the highest level of preparedness. This is likely to be the most stressful winter we have had in a number of years in terms of waves,” said Brett Sanders, Chancellor’s Professor of Civil and Environmental Engineering at the University of California, Irvine.

A marine heat wave that has been evolving since last winter, combined with the strengthening El Nino, has provided plenty of fuel for tropical cyclones offshore. These storms have sent numerous rounds of large waves towards Southern California during much of the summer. The combination of large waves during high tide brought significant coastal erosion impacts to several communities in Southern California, including Malibu, Laguna Beach, Long Beach, Dana Point and Carlsbad.

Significant coastal erosion events during the summer are unusual but not unprecedented. But Alexander Gershunov, a climate researcher at Scripps Institution of Oceanography, told ABC News that the winter may be particularly challenging for Southern California because of El Nino.

“There is a higher likelihood of coastal erosion events during El Nino winters. It makes it more likely it will be more stormy in the northeastern Pacific, which spells more wave action along the coast of California.”

This increases the potential for damage to coastal communities, including landslides and cliff collapses, such as the ones in Del Mar, California, that shut down train service in the past.

Gershunov also noted that “El Nino is a natural pattern, but it is occurring in an unnaturally warming world,” and it may turn out to be the strongest on record.

Sanders said that since March, sea level has been around six inches higher than normal due to El Nino and that it will peak in November and December when El Nin

o is at full strength. He expects another six inches of sea level rise in the coming months.

To make matters worse, Sanders warns that ocean tides in November, December and January are likely to be the highest in a number of years due to natural cycles related to the sun and the moon.

When you combine the higher sea level, the high tide cycles and the possibility of winter storms, there will likely be a lot of wave energy hitting the Southern California coastline. Communities right along the coast will be facing the brunt of these waves, according to experts.

“What you are seeing is likely a wake-up call for some of the issues we may be facing this winter,” said Adam Young, a coastal geomorphologist at Scripps Institution of Oceanography. “To have so many different erosion issues on so many different parts of the coast is unusual.”

Most of the coastal erosion we have seen this summer has been along southwest-facing coastlines, with swells coming primarily from that direction. During the winter, when storms roll across the Pacific, most of the wave action will come from the west and northwest and will affect those corresponding communities.

The city of Carlsbad, which has faced prolonged erosion impacts, has declared a local emergency to expedite coastal stabilization efforts to prepare for the possibility of strong El Nino conditions.

“As we’ve seen throughout this year, the city takes a proactive approach to monitoring and maintaining our infrastructure, particularly ahead of storm seasons, so we can identify potential issues and address them before they become problems,” Geoff Patnoe, Carlsbad City Manager, said in a statement.