The reason why your hair is damaged after a trip to the beach... ...is because the ocean's salinity and the wind-blown salt particles that get stuck in your hair, causing it to lose its moisture. And then, the UV rays damage your dried hair.
海で 髪が 傷む 原因は 海水や 潮風に 含まれる 塩分が 付着して、 水分を 失った 髪が 強烈な 紫外線を 浴びて 傷むからだそうです