Swept away: beaches, dunes and wharves pulled out to sea.

By Charles Mandel
CHARLOTTETOWN, Prince Edward Island, Canada. April, 2005

Visitors to Prince Edward Island who return after being away for a while may be in for a shock. Some of the scenic spots on the tiny province’s coastline are changing beyond recognition.

At Basin Head, one of the Island’s world-renowned beaches, the wharves have been washed away, as has a major sand dune that anchored them. Gone are the famous Panmure Island dunes. The story is the same in the P.E.I. National Park, where tonnes of sand forming the attraction’s dunes have been dragged out to sea.

The major damage came from a strong storm surge on Boxing Day, 2004, when the winds hit 90 kilometres an hour. Battered along with the dunes were a variety of human structures, including seaside cottages, wharves and part of the Crowbush Golf Course.

Unlike tsunamis, which are caused by underwater activity such as earthquakes, powerful tidal surges are triggered by above-surface conditions such as high winds. Surges are the ocean’s response to approaching storms.

Accompanying near-shore winds can cause water to pile up toward land, causing storm surges of up to two metres in Canadian waters.

“The wind is the key,” Peter Bowyer, program manager of the Canadian Hurricane Centre, says on an Environment Canada website. As a storm approaches a coastline, the difference in atmospheric pressure over a small area of geography pushes the ocean surface ahead of the storm, he says.

Other factors such as the speed of the storm’s motion, the angle at which the storm makes landfall with the coast, and the shape of the seabed help to determine the specific storm surge experienced at each point along the coast, Mr. Bowyer says, but the wind is the most important factor.

Charles O’Reilly, the chief of tidal analysis and prediction for the Canadian Hydrographic Service, cautions not to confuse storm surges with storm waves, which he describes as “the angry part of the ocean.”

A storm surge on top of a high tide allows the energy of the storm waves to encounter objects higher up on land than before.

The problem for people is less the storm surge, than the fact that people persist in building near the shore. And in their efforts to ward off the sea, coastline dwellers are, in fact, increasing the problem, according to Cornelia Dean, a science writer with The New York Times and author of Against the Tide: The Battle for America’s Beaches.

In her 1999 book, Ms. Dean details a variety of ways in which people interfere with natural processes such as storm surges, and compound the problem through the use of barriers and breakwaters. She argues that coastline development such as seawalls result in beachless beaches as the ocean relentlessly forces the sand around barriers, causing further erosion.

In Basin Head, the tourist attraction is P.E.I.’s oldest lobster cannery, a historic site that is the result of a decision in 1937 to dredge a harbour and establish fishing wharves. The storm surge moved the entire building four to five feet. Of equal concern is the preservation of the beach, which is made of fine white sand that makes a squeaking or “singing” sound under foot pressure. 

David Linton, the field unit supervisor for Parks Canada in PEI, partly blames climate change. On the night of the Boxing Day storm, it was warm enough that ice had not yet formed along the shoreline. Because of a lack of protection from the ice pack, the surge roared up and over the dunes. “A lot of this is climate warming and we’re noticing that frost comes later every year.”

Gerald MacDougall, provincial climate change co-ordinator, predicts increased storm surges, and damage to beach-front facilities and homes built too close to the ocean or in food plains. 

Generally, though, Canada has better setback regulations than the United States, where little has been done to discourage building next to the beach.

Ms. Dean said in a phone interview that last year she visited Florida and Alabama where one of the region’s four hurricanes had made landfall. “Within a week after that storm had passed through, when they were still bulldozing sand out of the streets, they were there hammering away on the high-rises right on the beach with no setback at all. You have to look at that and say, ‘What exactly are these people thinking?’ “

Orrin Pilkey, a professor emeritus at Duke University in Durham, N.C., who has studied coastal development, says setbacks aren’t much help. North Carolina came up with them 29 years ago, putting beach-front property back 30 times the annual erosion rate. “So guess where those houses are now?” Dr. Pilkey says.

Have storm surges increased? It’s hard to tell because of a lack of long-term records. And David Scott, a micropaleontologist who studies marine geology at Halifax’s Dalhousie University, says it is sheer speculation to say climate change will result in more frequent storms. “Nobody can predict that. It could get better, it could get worse.”

He points out that if the climate warms up, things could go either way, and he notes that 5,000 years ago the area surrounding the Northumberland Strait region was 10 degrees warmer — more like Virginia in climate. “There isn’t any more evidence that there were any more storms then.”

Copyright © 2013 Charles Mandel

Originally published in The Globe and Mail April 30, 2005.