Sixty Years of Data Show Waves are Getting Stronger, Threatening Coastlines and Infrastructure

An aerial view of Colun Beach in the Valdivian Coastal Reserve, Los Rios, Chile. Photo © Nick Hall
An aerial view of Colun Beach in the Valdivian Coastal Reserve, Los Rios, Chile. Photo © Nick Hall

By The Nature Conservancy’s Dr. Borja G. Reguero and Dr. Michael W. Beck

Climate change is modifying the way our oceans work in many different ways, including ocean acidification and water warming. But where people really start to pay attention is where humans and oceans meet: the coast.

On the coast, most people have heard about sea level rise and assume that it is the major new problem affecting coastlines. This is because we have a great deal of tangible scientific evidence that sea levels have been rising, and we are able to project future changes with relative certainty.

There have been some changes in coastal policies around sea level rise (SLR) but overall it is hard to garner action around SLR, because it is a creeping problem with some of its greatest impacts many decades away (i.e., many election cycles).

There’s another force out there that garners less attention yet has an even greater effect in shaping our coasts: waves. It governs where we live and the coastal infrastructure we build.

In terms of both erosion and flooding, wave action is king. Waves drive everything on our coastline. They determine where the beaches, marshes and reefs occur. They shape our headlands, our bays and our open coasts. Waves determine where and in what direction we have built the hundreds of thousands of coastal defense structures (e.g., seawalls, breakwaters and dikes) we have erected over centuries.

Yet while sea level rise registers globally and while its future projections get clearer, we don’t yet have a similar degree of consensus and confidence when talking about the future of waves. Projections for future waves have until now been rare. Historical changes observed by buoys, ships, and satellites —> Read More