Rhode Island Sea Grant and the Coastal Resources Management Council are asking Rhode Islanders to take photographs documenting the effects of high tides in their neighborhoods. The photos will provide important information on local flooding, including trends over time, to coastal planners.
Known as ‘king tides,’ extreme high tides occur several times each year and often produce coastal flooding. CRMC coastal geologist Janet Freedman said king tides are normal events that are created when the sun, moon and earth align.
“It depends on the configuration of the different astronomical bodies,” she said. “Water is drawn by gravity, so when the sun, the earth and the moon are all lined up, there’s more of a draw of the water, so you get higher high tides and lower low tides.”
Westerly and Charlestown are among the coastal communities affected by king tides, the most recent of which occurred on Oct. 27 to 30. Another king tide will take place on Nov. 26.
Charlestown Planning Board member Ruth Platner said she had published an invitation in the Charlestown Citizens Alliance newsletter asking residents to get involved in the king tide reporting initiative.
“I did that to help Sea Grant get their message out that they needed photographs,” she said. “During the great flood of 2010, we asked for citizens to send the CCA photographs and those ended up being really useful. They were used by emergency management and others. It doesn’t seem scientific, it’s kind of anecdotal, but it is evidence and it does provide nice visuals. If we want to go back and know if it flooded someplace, we can see where it did flood.”
The National Oceanic and Atmospheric Administration, which predicts king tides, states that current atmospheric conditions and sea level rise are expected to produce more coastal flooding.
“From May 2019 to April 2020, high tide flooding will occur about twice as often as levels typically observed in 2000,” NOAA’s website states. “El Niño conditions that are predicted to persist through 2019 are a factor for the increase, along with continued sea level rise.”
Photographs are submitted to the MyCoast website, a national portal for reporting and recording storm damage, high tides and other coastal events. MyCoast is funded by a regional coastal resilience grant through the Northeast Regional Ocean Council, an initiative of the federal government and the New England states that encourages collaboration on regional issues such as ocean uses and conservation.
The Rhode Island-specific MyCoast website is operated by the CRMC, the University of Rhode Island's Coastal Resources Center, Rhode Island Sea Grant and Save the Bay. In addition to king tides, the Rhode Island site records storm damage and coastal change and the free MyCoast app allows citizen scientists to post and view photographs. To date, 388 Rhode Islanders have joined.
Sea Grant extension specialist Pamela Rubinoff said Rhode Island residents were first invited to submit their high tide photos in 2012.
“Rhode Island Sea Grant did a photo contest to get people to take pictures of high tides,” she said. “We very much recognized that this was wonderful and how do we start to institutionalize it.”
Freedman noted that the photos are also compared with coastal flooding predictions on the CRMC’s interactive STORMTOOLS map.
“We can look at the location on our STORMTOOLS site so we can look at where we’ve predicted sea level rise in a certain place and we can actually see when the seas are that much higher than normal and what floods,” Freedman said.
“It’s actually more complicated than just the sea level going up and down, because we’ve found that when the sea level rises, it infiltrates areas that don’t have a direct connection to the water through the stormwater infrastructure, so you’re getting salt water coming in instead of the rainwater going out.”
Storms will also produce higher water levels than those predicted on the tide tables.
“If we’re having a nor’easter or another kind of storm, the water levels go up,” Rubinoff said. “So sometimes, it wasn’t even a predicted high tide, but we’ll see more extreme high tides in a storm cycle. If people keep track of high tides, then they might see a time that we haven’t identified.”
The photographs and accompanying information, such as location, weather and the time the photograph was taken, are added to a database that helps researchers track coastal flooding trends.
Another important benefit of submitting high tide photos, Rubinoff said, is that people are actually witnessing the effects of sea level rise.
“People were not as aware that our seas were rising and there were some people that really believed it and some people that didn’t, so we started to say ‘let’s start to look at what our communities look like at extreme high tides’ and then, if you start to see it and you start to notice it, you might start noticing that it’s more and more, something that you never saw before,” she said.
People can submit their photos using the MyCoast app or by logging onto the MyCoast website at https://mycoast.org/ri.