Climate Change > What is climate change? > King Tides

King Tides in Washington state

The highest tides in Washington usually occur during the winter. These higher tides, referred to as "King Tides," occur naturally when the sun and the moon align, causing an increased gravitational pull on the Earth's oceans. King Tides can cause high water levels that change the way we interact with our shorelines and infrastructure.

King Tides help us visualize climate change

King Tides give scientists and citizens a peek into one way climate change will impact our lives: sea level rise. As global temperatures rise, the oceans warm slightly and expand, ice caps and glaciers melt, and more precipitation falls as rain instead of snow. This causes sea levels to rise. Some models predict Seattle may experience a sea level rise of two feet or more by the year 2100.

These rising sea levels are expected to:

• Intensify flooding in coastal areas, especially during high tides and major storms
• Cause erosion that shifts coastal beaches landward
• Threaten buildings, roads, utilities and other coastal infrastructure
• Increase coastal bluff erosion, endangering houses and other structures built near the bluff edges
• Threaten coastal freshwater and coastal aquifers (underground water supplies)

Get involved during the 2016-2017 King Tides season!

We invite you to grab your camera or phone and head to the beaches to take photos of Washington’s King Tides. Documenting how very high tides affect the natural environment and our coastal infrastructure will help us visualize what sea level rise might look like in the future. We need your help to document these king tides and raise awareness about the impacts of climate change on our coastline.

We partner with Washington Sea Grant for the state’s Witness King Tides project. This project invites people to visit the shoreline and capture images of important places threatened by sea level rise. Visit Washington’s Witness King Tides website for information on King Tide schedules, locations, and how to share your photos on the site.

Thank you for helping us track this year's King Tides! Search #kingtides on Facebook, Instagram and other social media channels to see photos from King Tides Photo Initiatives around the country and the globe.

King Tides depend on the weather

Tides are consistently higher during the winter season than the summer, but weather conditions also affect when King Tides occur. Low atmospheric pressure can raise water levels and can sometimes cause an extremely high tide to occur even when a King Tide is not predicted. On the other hand, high atmospheric pressure can cause a predicted King Tide to be lower than expected. These factors make predicting the highest tides of the year very difficult. However, King Tides are most likely during the late fall and winter storm season when low-pressure weather conditions happen frequently.

Citizens can watch for unusually high tides using NOAA’s Tides and Currents website. Simply click on the station closest to your area, and view the predicted (blue) and observed (red) tide levels. Checking this site each day or each week can help you see how tides are affected by the seasons and the weather. You can also use the site to watch for potential King Tides.

This NOAA tidal plot shows that actual tide levels (red) were higher than predicted levels (blue). King Tides are especially likely when low atmospheric pressure raises water levels higher than predicted.