The fear is that melting ice, along with increased snow and rain, could reduce the density and salinity of the top layers of the sea, making them more buoyant.

人们担忧的是正在融化的冰和不断增加的雨雪可能降低海洋表层水体的密度和盐度，导致其更容易滞留在海洋表层。

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But overnight rain left large patches of ice on the course, making it too dangerous.

BBC: Aviemore dog sled race cancelled over safety concerns