Every year in early winter, high tides on the Oregon coast are higher than usual. These extreme high tides, commonly called “king tides,” occur at a few specific times during the year when the moon’s orbit comes closest to the earth, the earth’s orbit is closest to the sun, and the sun, moon and earth are in alignment, thereby increasing their gravitational influence on the tides. These tidal events are also known as perigean spring tides.
And every winter for the past decade, a growing network of volunteer photographers has documented the highest point reached by these highest of tides. The hundreds of photos they take capture a moment in the interaction between land and sea, which up till now has been rare but is likely to become far more typical. The images reveal current vulnerabilities to flooding. Even more important, they help to visualize and understand the coming impacts of sea level rise — such as flooding and erosion — to coastal communities. These tides are especially important to document when storm surges and high winds and waves create even higher water levels.
The volunteer photographers are participating in the King Tides Project, the Oregon branch of an international grassroots effort to document coastal areas flooded by the highest winter tides. It started in Australia, and in 2010, West Coast states, including Oregon, began to document their king tides. In 2012, the project spread to the East Coast and continues to expand today.
In Oregon, the King Tides Project has been developed and coordinated by the CoastWatch Program of the Oregon Shores Conservation Coalition and the Oregon Coastal Management Program. From modest beginnings, the project has grown to the point that more than 100 volunteer photographers contributed more than 400 photos to the project’s archives last winter.
The goal of this citizen science project is to encourage Oregonians and visitors to submit photos they take of the king tides to help track sea level rise over time and reveal its impacts on the Oregon coast. The value of the project thus increases over time, as the record of changes caused by higher tides lengthens. Photographers are also encouraged to take photos at average high tides from the identical vantage points of their “king tides” shots, for purposes of comparison.
Anyone can participate by taking a photo during the peak period of a king tide, anywhere on the outer coast or along estuaries or lower river valleys. Photos that show the highest stand of the tide with reference to a man-made structure or natural feature reveal the reach of the tide most clearly. Participants then submit their photos through the project website (www.oregonkingtides.net).
This year, the three sequences of king tides that will be the focus of the project take place Nov. 15-17, Dec. 13-15, and Jan. 11-13, 2021.
For more information, contact Meg Reed, coastal shores specialist with the Oregon Coastal Management Program, 541-514-0091, [email protected]; or Jesse Jones, CoastWatch volunteer coordinator, 503-989-7244, [email protected]