Tag Archives: tides

King Tides don’t always follow the tide tables

UPDATE: Dec. 19

An app used for reporting King Tides can also be used to report marine debris along the shoreline. Check out the news release issued today by the Washington Department of Natural Resources.

Higher-than-predicted marine waters, brought about in part by recent weather conditions, have given us unexpected “King Tides” in many areas of Puget Sound.

I noticed that the waters of Hood Canal seemed exceedingly high this afternoon, as I drove along Seabeck Highway where the road hugs the shoreline. The waters were not supposed to be this high, according to tide tables developed by the National Oceanic and Atmospheric Administration, so I checked some actual levels recorded at nearby locations.

High-water levels measured on the waterfronts in Seattle, Tacoma and Port Townsend were nearly 1½ feet higher than what had been predicted by NOAA for those areas. For example, in Seattle the preliminary high-water level was listed at a tidal elevation of 12.98 feet at 12:54 p.m. today, compared to a predicted high tide of 11.56 feet.

This is the season for King Tides, a name given to the highest tides of the year. High tides, mostly generated by the alignment of the sun and the moon, are predicted for Christmas Eve, rising higher to the day after Christmas and then declining. But, as we’ve seen this week, as well as on Thanksgiving Day, predicted high tides can be dramatically boosted by heavy rains, low atmospheric pressure and onshore winds.

As one can see by looking at observed and predicted tidal levels in Seattle, the actual tidal level has exceeded the predicted level more often than not over the past 30 days — and lately it has been higher by quite a lot (shown in chart at bottom of this page). Actual levels are measured in real time in only 14 places in Washington state. One can access the charts from NOAA’s Water Levels — Stations Selections page.

King Tides are promoted as an event by Washington Sea Grant and the Washington Department of Ecology, because today’s extreme tides provide a reference point for sea-level rise caused by climate change. The highest tides of today will be seen more often in the future, and even higher tides are coming. Check out the blog post on Water Ways from Jan. 3 of this year. See also the website “Washington King Tides Program.”

Washington Sea Grant has posted a list of dates when high tides are expected in various areas, called King Tides Calendar. Sharing photos of high tides hitting the shoreline is part of the adventure, so sign up for MyCoast to share your pictures or view images posted by others, or download the cellphone app to make the connection even easier.

The chart shows the actual tidal water levels in Seattle (red) compared to the predicted levels (blue). Click to go to NOAA’s website.
Chart: NOAA

Be alert for tidal flooding and King Tide photos

Some of the highest tides of the year, combined with a strong low-pressure system, could provide “King Tide” observers with ideal conditions tomorrow (Monday) for taking pictures of near-flood conditions or even flooding in some places.

This is the third year the Washington Department of Ecology has put out a call for photos of high-tide conditions.

Photo of Poulsbo waterfront taken during “King Tides” Dec. 28, 2011.
Photo by James Groh, Poulsbo

“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,” states Ecology’s “Climate Change” blog.

The King Tide photo initiative began in Australia in January 2009. Washington and British Columbia joined in 2010, followed by Oregon and California in 2011.

Tide tables predict that tides in Bremerton and Port Orchard will reach 13.4 feet at 8:28 a.m. tomorrow. Check on other locations and other days in Washington state at Saltwater Tides.

The National Weather Service has issued a coastal flood advisory for Western Washington because of low-pressure conditions, which could add 1.5 feet to the tide table prediction. That would put the Bremerton area at 14.9 feet. Check out the Weather Service advisory and the Kitsap Sun story.

While it looks like we’ll have a very high tide, it probably won’t be a record. I was unable to find historical data for Bremerton, but the record high tide for Seattle is 22.4 feet on Jan. 27, 1983. The tide tables predict that Seattle will reach 12.5 feet tomorrow, or 14 feet with the added 1.5 feet because of the low pressure.

Historical data can be found on NOAA’s “Tides and Currents” webpage after selecting a station.

Shortly after I posted this, Jeff Adams of Washington Sea Grant sent me an email to point out that NOAA’s numbers need to be corrected by subtracting 7.94, because NOAA uses a different baseline than we commonly use in this area. That would place the record in Seattle at 14.5 feet, much closer to what we may see tomorrow. I should have known that something was amiss with that data. For more on this point, check out Jeff’s blog, Sea Life. 

King Tides will continue through this week, declining slightly each day, then will return on Jan. 14.

I’m certainly not hoping for high water levels, but where they occur it would be great to have some photos. Feel free to send them to me at cdunagan, as well as uploading to the Flickr page called “Washington King Tide Photo Initiative.”

‘King tides’ are an invitation to take watery photos

The Washington King Tide Initiative is entering its third year, and state officials would like people to shoot photographs of flooded roads, yards and buildings — if such events occur.

The high tide at the mouth of Gorst Creek comes close to reaching Toys Topless in Gorst. Photo by Meegan M. Reid, Kitsap Sun
In 2010, the high tide at the mouth of Gorst Creek comes close to reaching Toys Topless at the head of Sinclair Inlet in Gorst.
Photo by Meegan M. Reid, Kitsap Sun

High tides are expected to continue for the next few days and return to high levels again in mid-January. Whether flooding occurs at any one place depends on rainfall, winds and atmospheric pressure, as well as tidal levels dictated by the position of the moon and sun. (See NOAA Ocean Service Education.)

Not much flooding occurred during king tides last year, but plenty of photographs were collected in early 2010. That’s when the picture on this page was taken in Gorst between Bremerton and Port Orchard. For additional photos, check out the Flickr page or the video slide show put together by the Washington Department of Ecology.

Taking note of these high tides is one way to gauge how climate change may affect shoreline areas. Over the next 100 years, sea level is expected to rise by at least 2.6 feet, according to the U.S. Fish and Wildlife Service, although previous estimates by the Intergovernmental Panel on Climate Change were in the range of 7 inches to 2 feet.

The King Tide Initiative started in Australia in 2009, according to Ecology’s website on King Tides, but it soon became a project for the West Coast of North America, with Washington and British Columbia joining in 2010 and Oregon and California joining in 2011.

Visit Flickr pages for British Columbia, Oregon and California, which includes regional pages for San Francisco Bay, Santa Monica and San Diego.

For a list of high tides, go to Ecology’s King Tide Schedule page and click on the map. More precise information can be found on NOAA’s page of tide predictions, where you can zoom in to your area of interest.

For past King Tide events, check out my Water Ways entries for Jan. 21, 2011 and Feb. 1, 2010.

Lunar energy could offer a steady, predictable supply

The gravitational pull of the moon offers an enormous potential to provide electrical power, since ocean tides move massive amounts of water on a regular schedule.

Harnessing ocean energy has the potential of providing a steady, predictable power supply. And, while wind and solar power are still favored on a cost basis, tidal power has the benefit of being always on, undiminished by clouds or lack of wind. That alone is considered a major benefit when it comes to operating the regional power grid.

This week’s conference on ocean energy in Bremerton turned out to be interesting, not only for the types of technology discussed but also for its variety of viewpoints — including fishermen who want to make sure tidal turbines don’t hurt their operations. Check out the story I wrote for Thursday’s Kitsap Sun.

In the Puget Sound region, the Snohomish County Public Utility District is studying the potential environmental effects of placing a tidal turbine in Admiralty Inlet between Port Townsend and Whidbey Island. A small pilot project is all that is planned at this time.

At the Bremerton conference, Jim Thomson of the University of Washington described some of the ongoing studies, from measurements of currents passing through Admiralty Inlet to the possible effects of noise on sealife. So far, concerns appear to be manageable. I reported some of Thomson’s comments in my story.

Another news report on the project itself was written this past summer by Charlie Bermant of the Peninsula Daily News. Charlie reported that the latest schedule calls for installing the turbines in 2013.

The top video on this page depicts a commercial turbine developed by OpenHydro, the company working with the PUD on the Admiralty Inlet site. The second video, though made in 2008, offers a nice perspective of the overall effort by SnoPUD General Manager Steve Klein.

Worldwide, the quest for energy is not bypassing the gravitational power of the moon. John Daly of Oilprice.com reported last week that Rolls Royce, which has become a formidable player in the energy business, has developed a tidal turbine that could make inroads into Great Brittain’s electrical needs — although Daly failed to describe the potential cost obstacles.

Needless to say, this subject is worth following, and sponsors of the Bremerton event — including organizer Cleantech West Sound — are already discussing new issues that could be discussed at a repeat conference next year.

Charts, tides and currents just a click away

When I need a nautical chart for the Puget Sound area, I’ve begun to click on a website called DeepZoom, a site that takes you into an animated wonderland of tides and currents.

Software developer Jay Alan Borseth of Seattle is using Microsoft’s DeepZoom technology to weave together hundreds of charts and maps, allowing the reader to quickly scan and zoom to the location of interest. The whole thing runs on Silverlight.

Unique features about the website are not the static maps but the ability to watch changes in tides and currents. Pick a location, type in the date and set the duration of time you wish to review. Use the slidebar to set the clock for checking on tides and currents at a specific time. Or click the start button to play through the animation for the sequence you have chosen.

How fast you move through time can be changed by adjusting the rate.

If you zoom out far enough to see the entire United States, you can even watch the sun and moon move across the sky.

Jay told me that he believes the Puget Sound region is fairly complete, especially for the nautical elements. Other parts of the U.S. and the world are still works in progress, however. He also envisions integrating other types of charts and maps for planes, trains and automobiles. Some of these elements are already accessible by clicking at the top of the page.

The idea for animating the currents came to him as he was reviewing charts for boating, he said. He expects the basic website to stay free for users, but he may develop a mobile application that could be commercialized.

“It’s about halfway through,” Jay told me, “but it is momentarily on hold.”

He explained that he is working on other software applications now occupying his time, but he hopes to get back to this project.

If anyone knows of other web-based charts and graphs that are particularly interesting, please feel free to share them.

Grab your camera to share some high-tide photos

With extreme high tides coming over the next few days, it may be a good time to shoot some photos of the shoreline, as suggested by the Washington Department of Ecology in a news release. Some of the highest tides of the year will be visible during daylight hours.

The high tide at the mouth of Gorst Creek comes close to reaching Toys Topless in Gorst. Photo by Meegan M. Reid, Kitsap Sun
Last year about this time, the high tide at the mouth of Gorst Creek comes close to reaching Toys Topless in Gorst.
Photo by Meegan M. Reid, Kitsap Sun

The idea of observing shoreline areas during extreme tides is part of an effort to make people aware of climate change, which is expected to cause extreme tides to become more extreme. By 2050, climate models suggest that we could see water levels about six inches higher for the same tidal cycles, according to Ted Sturdivant, director of Ecology. Here’s his statement:

“Understanding what climate change will mean to our environment is a key to making Washington climate-smart, and these very high tides are like a window into the future.

“As sea level rises in the years to come, many of our shorelines — including those in our most populated areas — are very likely to be affected. By inviting the public to help us document the effects of higher water levels during king tides, we are laying the groundwork to help communities identify those areas most vulnerable to coastal flooding.

“This work will help us anticipate what Washington communities can expect along much of our state’s thousands of miles of tidal coastline.”

Ecology compiled a list of the predicted tides and related times for 14 locations in Western Washington. See King Tide Schedule (PDF 41 kb).

If you get some good photos, Ecology would like you to share them on Flickr by going to Washington King Tide Photo Initiative.

During the king tide season last year, people seemed fairly interested in this topic, and some pretty good photos were submitted. Check out my entry in Water Ways for Feb. 1, 2010.

As a bonus, Jim Aho of Illahee tracked down some pretty interesting information about tides for the Illahee Community Blog.

Ecology wants help in photographing high tides

Extreme high tides from now until Wednesday and again in February could give an indication of how this state will contend with rising sea levels over the coming years, according to Spencer Reeder of the Washington Department of Ecology.

<small> Photo courtesy of Washington State Ferries</small>
Photo courtesy of Washington State Ferries

It’s worth mentioning here because Ecology is asking average people to photograph conditions related to the high tide and provide the exact time and location of the picture.

“The agency is interested in using these images to help document the coastal impacts our state is likely to face with increasing frequency as sea levels continue to rise,” Reeder says in a blog entry on EcoConnect.

Precise times for high and low tides vary by location, but one can get a pretty good estimate by going to the tide prediction Web site operated by the National Oceanic and Atmosphere Administration and drilling down to the closest community listed.

Pictures can be sent by e-mail to Ecology, placing “sea level rise” in the subject line. Folks are encouraged to include contact information, so Ecology can send a release form to allow publication of the photos.

Weather conditions, such as wind and rain, can affect localized flooding and related problems, which is one reason to get as many varied locations as possible.

Reeder’s blog states:

“Increases in global sea levels have been recorded by NOAA tide gauges for many years, and more recent observations have been collected by NASA satellites. The steady rise has been attributed to both a warming of the oceans and contributions from melting glaciers and land-based ice sheets. Climate modeling combined with these direct observations suggest sea level rise will continue well into the future with significant implications for Washington’s more than 3000 miles of marine coastline.

“Analysis conducted by the University of Washington’s Climate Impacts Group and the Washington State Department of Ecology show that increases in sea level in Puget Sound could be as high as 22 inches by mid-century, with upper estimates of more than four feet of rise by 2100.”