King Tides, Harbingers of Climate Change, are Coming

Our Coast Our Future
By 2040, scientists predict sea levels rising 20 inches, shown in light blue | photo from | post by Jen Gennari

It’s that time of year again, when winter storms paired with extra-high tides increase the risk of flooding. King tides, the common name of perigean tides, are scheduled for Nov. 14 to 17 and again Dec. 13 to 16. Be prepared for flooding on Gate Five Road, around Marin City and the Manzanita Park and Ride, and the Sausalito-Mill Valley path and Gate 6 1/2.

The California Coastal Commission encourages people to submit photos of high water to The King Tides Project. These images are useful to educate others about the coming sea level rise, which in Marin is projected to be anywhere from one to three feet in the next decades.

Why is it important to monitor king tides? A new study released in 2019 from the U.S. Geological Survey says that once tides, storms, and erosion are taken into account, the predicted damage caused by rising seas triples. Read an article on KQED about that prediction or see prediction using an interactive map from Our Coast, Our Future.

Here is the chart for our neighborhood:

Date Time Height
Saturday, November 14 10:16 a.m. 6.6
Sunday, November 15 10:54 a.m. 6.8
Monday, November 16 11:36 a.m. 6.8
Tuesday, November 17 12:20 p.m. 6.6
Saturday, December 12 9:04 a.m. 6.7
Sunday, December 13 9:45 a.m. 6.9
Monday, December 14 10:29 a.m. 6.9
Tuesday, December 15 11:14 a.m. 6.9
Wednesday, December 16 12:00 p.m. 6.6

The Coastal Conservancy offers a clear explanation of why and how the seas are rising:

Carbon dioxide in our atmosphere acts like a blanket, trapping in heat that would otherwise escape, and when we burn fossil fuels, we’re adding more carbon dioxide, “thickening the blanket” and warming the planet and ocean. Sea level is rising because land-based glaciers and ice sheets are melting into the ocean and also because water expands in volume when it warms.

Marin County, with its low-lying areas, has been making adaptation plans. Three concepts to elevate the path are under consideration, and Drawdown Marin outlines the six key areas the community is addressing to reduce our carbon footprint.

Here in the floating homes, FHA environmental committee volunteers have been tracking how close the bay is rising under our docks using yardsticks. If you capture any significant flooding in our community, please send photos to Jen Gennari. To read about the yardstick project in prior years, read King tides volunteers check bay level.