"...at sea he is perpetually nauseous."
I myself suffered terrible sea sickness for years. It is a misery difficult to describe to them that have not suffered it. I found that the bigger the boat I was on, the further below deck, the longer and slower the roll, the worse I suffered, and on the smallest skiffs most storm tossed and batted about by waves, I suffered not at all. I enjoyed the thrill immeasurably, viscerally, primally excited by the unpredictability of the existential danger. Flying off the crest of a 20 meter swell, in a 3 meter flat bottomed aluminum skiff, bursting out of the Pacific in pitch black of an overcast and raging storm at night was an experience I can never forget, nor remember without tasting the metallic flavor of the blood in my mouth (from nipping my lips and tongue when unpredictable chop battered me), the chill of the North Pacific spray serially inundating me, and the coursing of the electric passion through my veins as I defied death. I floated in the air down towards the trough of the storm swell for an eternity, in the darkness blind to what lay ahead, and loved life that moment with a fervor no woman, no family, no drug will ever kindle.
A very strange affliction, indeed. I eventually learned to simply will myself not to be nauseous, somehow, and managed to serve a state agency as an experimental biologist on a population dynamics study of Sebastes (rockfish) and Onchorhynchus (salmons) prior to 9/11, riding charter boats out of a fishing village to track and genetically sample their catch (and watch the clients suffering sea sickness chum). However, I hated government work with more passion than I loved the sea, and have thereafter worked in the trades happily.
Ursula K. LeGuin rejected a story I sent her with such derision and vehemence I never again submitted any writing to any publisher until I entered a contest on Hive's predecessor, and discovered the joys of editing. Editors, I have found, are as useful as the sea, and similarly cause more suffering the larger the work being edited. I managed to learn much from them and even enjoy the ride when they bettered my meager short story submitted to the contest - but I have realized I would never survive the editing of a more substantial work, and can't write fart professionally without their literary acumen.
Edit: edited for literary acumen.