HALIFAX — After four days of scanning the Atlantic, U.S. and Canadian authorities have scaled back their search for a solo sailor from Nova Scotia who was caught in a violent storm as he sailed to Bermuda.

Hubert Marcoux, a 67-year-old author and adventurer, left the province Nov. 9 and was supposed to reach Bermuda last Monday.

The Halifax man has been described as an experienced sailor who wrote a book in 2005 about his 18-year voyage around the world.

The search for Marcoux and his 14-metre boat Mon Pays began Thursday.

At that point, the area Marcoux was sailing through had already been battered for days by 110-kilometre per hour winds and waves as high as three-storey buildings.

"He ran into the remnants of a storm coming up the coast," said Jeri Grychowski, spokeswoman for the Rescue Co-ordination Centre in Halifax.

On the weekend, Marcoux's sister said she was convinced he had been swept far off course by the storm.

Lucy Milroy said she believed Marcoux was drifting somewhere in the Atlantic.

She said she last spoke to her brother when she saw him off two weeks ago in Halifax.

Marcoux's sailboat was reported to have a VHF radio, personal flotation devices, flares and a dinghy.

Fixed-wing aircraft from Canada and the United States searched about 400,000 square kilometres of open ocean, but they turned up no clues as to Marcoux's whereabouts.

"The search for the Mon Pays has been officially reduced," said Grychowski. "There will be no more aerial searches."

However, search officials will continue to use VHF broadcasts to ask mariners in the area to keep watching for Marcoux's boat.