A King Tides Primer

How to Observe, Understand and Take Photos of this Season’s King Tides 

December 2022 - January 2023

We invite you to get outside and take part in the California King Tides Project’s Snap the Shore, See the Future sponsored by the California Coastal Commission. Because of sea level rise, the King Tides of today are the high tides of tomorrow. Take part in this community science project by taking photos of the King Tides and submitting them online using your smartphone. Your photos will help scientists and planners prepare for sea level rise in your area.

Main Causes of a “King Tide”

1. Moon phase (new moon and full moon cause the highest tides) - There will be a new moon on Dec. 23, 2022 and also on January 21, 2023.
2. When the Sun is at its closest point to Earth all year (called perihelion) - Perihelion on Jan. 4, 2023.
3. When the moon is at its closest point to the Earth each month (called perigee) - Perigee on December 23, 2022 and on January 21, 2023.

New Moon + Perihelion + Perigee = King Tide

This season’s King Tides, at San Francisco's Golden Gate Bridge

Resources from National Oceanic and Atmospheric Administration (NOAA) about Tides, Finding the Tides at Your Location, and Impacts of Sea Level Rise.

To find tidal information for locations in the USA, Pacific and Caribbean from NOAA:

https://tidesandcurrents.noaa.gov/tide_predictions.html

NOAA’s Sea Level Rise Viewer

View potential impacts of Sea Level Rise and High Tide Flooding for various locations in the USA, Pacific and Caribbean.

NOAA’s National Ocean Service Tides Tutorial

Exploratorium’s Tide and King Tide Resources

Main Causes of a “King Tide”

4. Moon phase (new moon and full moon cause the highest tides) - There will be a new moon on Dec. 23, 2022 and also on January 21, 2023.
5. When the Sun is at its closest point to Earth all year (called perihelion) - Perihelion on Jan. 4, 2023.
6. When the moon is at its closest point to the Earth each month (called perigee) - Perigee on December 23, 2022 and on January 21, 2023.

New Moon + Perihelion + Perigee = King Tide

From National Oceanic and Atmospheric Administration (NOAA)

NOAA’s Sea Level Rise Viewer

View potential impacts of Sea Level Rise and High Tide Flooding for various locations in the USA, Pacific and Caribbean.

NOAA’s National Ocean Service Tides Tutorial

To find tidal information for locations in the USA, Pacific and Caribbean from NOAA:

https://tidesandcurrents.noaa.gov/tide_predictions.html

From the Exploratorium

Full Spectrum Science Shorts: Tides (video)

What causes tides? Why are they sometimes high and sometimes low? Find out as we explore the forces of nature that cause this force of nature.

Full Spectrum Science Shorts: King Tides

At certain times of the year, we're treated to—and sometimes terrorized by—extra high and extra low tides called "King Tides." What causes these extraordinarily large tides?

Dance of the Tides Science Snack Video

Find out how gravity and the distance between the Earth and the moon create tidal bulges (high tides) on both the near and far side of the Earth.

King Tides Explanation

A written description of the King Tides with illustrations from NOAA. Inspired by Dr. Paul Doherty, Senior Scientist at the Exploratorium, who loved the tides almost as much as he loved explaining them to others.

Learn more about Tides and Sea Level Rise with these three science activities from the Exploratorium’s Science Snack Collection:

        Tide O Matic

        Swelling Seas        

        Melting Ice and Rising Seas

Adaptation and Resilience Resources from the Port of San Francisco

The Seismic and Flood Risk 101 from the Port of San Francisco’s Waterfront Resilience Program (WRP) has good background information on SLR.

The Port’s Waterfront Resilience Program website

The Waterfront Resilience Story Maps on the WRP site has flood risk profiles of each subarea, with details of the risks for all affected parts of the City. Check out the neighborhoods that are meaningful to you and your students.

What can you do?

1. Find out more about Sea Level Rise and its effects on Environmental Justice Communities

Toxic Tides: Sea Level Rise, Hazardous Sites, and Environmental Justice in California

2. Learn more about climate solutions from Project Drawdown. One solution: Reducing Food Waste