You could certainly sail from
California to Alaska, but you would be best off heading west several hundred miles until you catch favorable
wind to take you north, then catch the westerlies to
head towards
British Columbia. If you try to hug the coast you will have adverse
wind and currents impeding your voyage. From Alaska, sailing to
Japan would also have adverse wind and
current unless you proceeded well south, or took the
route of visiting Japan first and then riding
current and wind to Alaska. You could then
head south along the BC and
PNW coasts with favorable wind and current all the way to
California. Either
route, keep a close eye on local
weather and wind direction.