Sonya Baumstein lay in bed one sleepless night and wept softly as she pondered her upcoming attempt to cross the Pacific Ocean alone in a rowboat.

"I was just thinking about the fact that I'm going to be leaving everything that I love for a really long time," Baumstein said of her planned 9,600-km odyssey. "And I don't know the consequences."

The 30-year-old from Port Townsend, Washington state, has undertaken endurance feats in the past, but her journey from Japan to San Francisco, expected to start around next Monday, is her most daunting adventure yet.