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How does evaporated ocean water from tropical cyclones lose its salinity when it rains?

Dear Tom,
I’m curious to know how evaporated ocean water from tropical cyclones loses its salinity when it rains.
— Aaron Duncan
Dear Aaron,
While it is true that the moisture from tropical systems comes from the oceans, the water from their rainfall is fresh, as it is from all weather systems. The reason is that only water evaporates from the oceans — pure water and nothing else.
Salt and other impurities do not evaporate and instead remain in the ocean, which is why the oceans remain salty. When it is windy over the ocean, spray is whipped into the air, and when the spray evaporates, its load of dissolved salt is left floating in the air. That’s why “sea air” is salty and can rust metal. Additionally salty seawater can affect the environment. When a hurricane storm surge sends a wall of seawater inland, the salt water can kill vegetation.