August 28, 2023

El Niño & Kelp: What Does It All Mean?

By Annie Bauer-Civiello, Reef Check Restoration Program Director

What is all the hoopla about this El Niño & what do the predictions mean for kelp?

You may have heard in the news lately about predictions of an intense El Niño event heading our way this winter. If you don’t know what this is, it is easy to go into an internet rabbit hole; we will keep this short and sweet. 

What is El Niño? A Super Quick Summary

El Niño Southern Oscillation Cycle (ENSO) has two opposing patterns — the El Niño and La Niña. These patterns are natural weather phenomena where the Pacific Ocean gets warmer (or colder) due to a combination of many different things. Since oceans are enormous bodies of water, it takes a long time for change to happen, but when it does, they have significant influences on different weather patterns. ENSO changes the wind, rain, and temperature on land and coastal water. This cycle typically occurs every 2-7 years. However, climate change is influencing the frequency of these events. Note that the impact of El Niño changes depending on where you are in the world. So, keep this in mind if you end up digging deeper.

On the West Coast of the United States, ocean water is cold and nutrient-rich, primarily due to upwelling. Upwelling is why you don’t want to get into the ocean without at least a wetsuit. It occurs when offshore winds pull warm surface winds off the coast and bring deep, cold, nutrient-rich water to the surface. El Niño weakens these winds, affecting the upwelling process resulting in warmer water temperatures.

What does this mean for kelp?

Kelp, such as bull kelp and giant kelp, thrive in cold, nutrient-rich water. Like plants on land, they like to grow in specific conditions. They don’t have roots, so instead, they rely on the ambient water conditions to thrive.

What kelp needs to grow: 

  • Nutrients
  • Sunlight
  • Cold water
  • A good balance of herbivores and predators

Over the last few years, we have been experiencing a La Niña period. This means that ocean waters are colder than average. Despite the recent challenges for kelp forest communities, this has been relatively good for kelp sporophyte survival and growth. However, several years of warmer waters will mean that it will be more challenging for kelp to grow. We saw signs of this in the 2015 El Niño event and the drastic impacts of the ‘blob.’

Moreover, changes in wind and temperatures can cause more intense storms. These storms can rip up kelp from the ecosystem. Increased rain events bring other problems, such as sedimentation and pollution from land.

If the El Niño event occurs at the severity level it is predicted, it means that the kelp needs our help more than ever. 

For the latest news on the ENSO forecast, check out this link.

We need YOU to help the kelp! Here are some steps you can take:

  • Learn about the importance of kelp forest ecosystems
  • Donate to support research and restoration
  • Participate in restoration activities

Read more about kelp forests, the effects of El Niño, and our restoration efforts here.