A lot of times the phrases "salt air" or "sea air" are used to describe the smell of the sea. So I would suggest using one of those phrases with another adjective that describes the coldness of the air: like "crisp salt air" or "icy sea air".
In low concentrations, these chemicals are described as smelling sealike, fishlike, and crablike. In really high concentrations, they come off as a harsh chemical smell, similar to iodine.
