A sunken cedar forest just off the coast of Bermuda proves the sea level around the Island has risen by more than 30 feet in the last 7,000 years, say scientists researching the find.

The forest, 33 feet below the surface near Gurnet Rock, close to Nonsuch Island, has been carbon dated to 7,293 years ago by North American scientists working with Bermuda's most famous explorer Teddy Tucker.

The team has also discovered a huge lake that existed for 900 years near Ferry Reach around 4,700 years ago, according to Dr. Steve Blasco of the Geological Survey of Canada, who is carrying out the research with Bermuda Underwater Exploration Institute (BUEI).

The story of the sunken cedar forest of around eight trees is the subject of a film, "Oceans In Motion," made by Dr. Blasco and Mr. Tucker which premiered at BUEI on Friday night.

It will be shown to an audience of around 15 million people when it is used as a learning tool in museums, schools and aquariums across North America.

The researchers have also found two other sunken cedar forests off the East End of the Island, at locations which have not been disclosed.

The forests are six feet and 26 feet below sea level. When the team carbon dates the cedar and compares them to the depth, it should prove the rate of sea rise.

Dr. Blasco told The Royal Gazette that due to global warming, the sea levels around the Island will rise by one and a half feet in the next 100 years.

According to Dr. Blaso, that means in the future, big hurricanes such as Fabian will wreak even more damage.

The research programme is designed to discover the rate of sea rise to allow Government to best protect the Island against future shore erosion and hurricanes.

"Over the last 18,000 years, the sea level has risen 350 feet and it continues to rise and is predicted to rise by another foot and half in the next 100 years due to global warming," Dr. Blasco told The Royal Gazette.

"The question is: 'what is the impact on Bermuda?' We've started to see it already with Fabian with a huge storm that has been more devastating than in the past because a higher sea level means the hurricane can reach further inland and cause further devastation.

"Future hurricanes are going to be like Fabian. If we go another 75 years, the next big hurricane will be even more devastating because the sea level will be one foot higher."

It will be up to Government and the Island to assess how to better protect Bermuda from rising seas, but Dr. Blasco suggests building further away from the shoreline, and bigger and heavier breakwaters.

"We are doing research on the history of sea level and the rate that it is rising. We need a clear understanding of what Mother Nature is doing to protect the coastline. Engineers and planners will decide how that is dealt with."

The trees in the sunken cedar forest have all been burned and the best theory is that this was due to lightening strikes after they were killed by rising sea levels.

But if the carbon dating of the other sunken forests indicates they all died around 7,293 years ago and they are all burned, that leaves open the possibility they were hit by a meteor strike, said Dr. Blasco.

But the most probable theory he is working is that it was rising sea levels that killed the trees.

"We believe the sea-level story, but we can't discard the other theories until we are sure this theory is correct," he said.

The cedar forest near Gurnet Rock was discovered by Mr. Tucker in 1957 and is thought the roots survived and were not washed away because it is protected by a reef.

The research team only decided to dive the site and date the trees to look for evidence of sea level rise when Mr. Tucker suggested it recently.