But to understand exactly how climate change is affecting the polar regions, the thickness of the ice needs to be known too.
但是，要准确了解季节的变化怎样影响极地地区，同时还要知道冰的厚度。
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Ittranspires that these are an uncommon set ofparameters in the polar regions, especially when your destination is a partially prepared landing area on sea ice of an unknown thickness.