A Glimpse into the Future: Understanding “King Tides” and What They Tell Us About Climate Change

Ebbing and flowing, tides are a constantly moving part of nature. At high tide, waters creep up the shore, filling salt marshes and covering our beaches. At low tide, we watch the waters pull back, revealing a plethora of exciting marine critters and hidden landscapes to discover. 

But there's one tide that making a bigger splash than the others—a "king tide".

What Is a King Tide? 

Tides are influenced by the gravitational forces exerted by the moon, sun, and Earth’s rotation. According to the National Oceanic and Atmospheric Administration, these are one of the most reliable natural phenomena in our world—even though both high and low tides range in intensity. The highest of all high tides has a very fitting name: the king tide. 

“King tide” is an informal term that refers to the time (once or twice a year) when tides reach exceptionally high levels. When the moon is closest to Earth in its orbit and the sun, moon, and Earth line up, their combined gravitational pull creates an especially strong tidal force. 

What We Can “Sea” in the Tides 

We know that climate change impacts are happening here and now and will only become more severe in the future without intervention. One of the effects of climate change we’re actively experiencing is sea level rise. Coastal flooding, extreme storm surges, beach erosion, and indicators like salt marsh vegetation growing higher on the land have been documented in Massachusetts. King tides can help us understand and adapt to these threats. 

That’s because while king tides are an astronomical phenomenon, they allow us to visualize what normal high tides will look like by 2050 if we continue to burn fossil fuels and release greenhouse gas emissions at the rate we are currently. Usually, we only see higher water levels during storms due to storm surge, but king tides provide a way to see “sunny day flooding” that’s happening when the ocean is relatively calm. 

King tides, even just bi-annually, can lead to coastal erosion and flooding, which puts shoreline communities at risk. These highest tides serve as a reminder that we must urgently act to both adapt to and mitigate the ”new normal” that will come if we continue on our current pace. 

Calling All Community Scientists 

That’s where you come in! We need all hands on deck to document king tides. Community photographs help scientists analyze coastal vulnerability to flooding and prepare ways for us to adapt to climate change. 

So grab your camera and find out when and where your nearest king tide will be, which are expected to be between 11 and 13 feet. Plan to arrive at least 15 minutes before the listed time as local conditions may vary. Once you’ve snapped a photo, submit them to the King Tides Project at MyCoast for this climate science initiative. 

But don’t stop there! Share your photos with us on Facebook or Instagram so that those not on the coast can see the power of king tides. 

Remember, safety first —visit MyCoast for tips and tricks on how to stay safe and still snag the best photo. 

Help Combat Climate Change 

Mass Audubon is one of the leading environmental nonprofit organizations specializing in nature-based climate solutions. Nature-based solutions use the power of nature to reduce flooding and extreme heat, limit the release of more greenhouse gases, and store carbon naturally. Find out more about Mass Audubon’s climate work

Become a member today to support our work in mitigating the effects of sea level rise through nature-based solutions, so that we can protect our coastal communities for people and wildlife.   

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