A massive underwater wave linked to this year’s El Niño weather system is progressing along the western shores of the Americas, sparking concerns among researchers regarding how climate change is amplifying the effects of this natural occurrence.
Known as the Kelvin wave, this phenomenon is not unexpected. However, its occurrence coincides with human-induced climate change that has already heated up the oceans and atmosphere. A smaller wave had already reached British Columbia earlier in the summer, with another wave anticipated to arrive within the next one to two weeks, as stated by Bill Merryfield, a research scientist at Environment and Climate Change Canada.
The Kelvin wave, like El Niño, is a natural weather event. In typical years, winds blow from the east to the west along the Pacific Ocean’s equator, pushing water from South America towards Asia. During El Niño years, these east-to-west winds weaken or reverse, allowing water to move eastward. When Kelvin waves hit the South American coast, the water accumulates and is forced to move up and down the Americas’ coasts, eventually reaching Canada.
Data from sea-level monitoring at Tofino, on Vancouver Island’s Pacific coast, indicates the impact of the earlier Kelvin wave in June. Rather than causing a massive tsunami-like wave, the Kelvin wave temporarily elevates sea levels, creating a broad, shallow bulge in the ocean surface.
The effects of this wave are most noticeable during king tides, exceptionally high tides resulting from the combined gravitational pull of the sun and moon. When coupled with a sea level rise of 30 centimeters and potential storm surges during winter storms, the impact can be significant.
The compounding effects of the Kelvin wave, stronger northward winds, and winter storms, combined with climate change-induced rising sea levels and increased extreme weather, could exacerbate coastal flooding and erosion. In the past, strong El Niños have caused widespread erosion along California’s beaches, prompting local authorities to take emergency measures.
Merryfield cautioned that the impacts of the Kelvin wave and El Niño could extend beyond the current season. During El Niños, some of the stored heat absorbed by the oceans from greenhouse gases is released into the atmosphere, potentially leading to 2027 being the warmest year on record by a considerable margin.
This warning echoes similar concerns raised by various climate research organizations and scientists, underscoring the potential long-term implications of these natural and climate-induced phenomena.