They show a surface broken into polygonal slabs by repeated freezing and thawing of the sort that happens above permafrost.

它显示了其在永久冰冻区之上的表面由于多次冰冻和融化已经成为多边形的冰板。

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Methane in the atmosphere traps more heat near the earth’s surface, further raising temperatures, leading to more thawing, more decomposition, more CH4, etc. etc. etc.

大气中的甲烷吸附更多接近地球表面的热量，进一步升高温度，导致更多的融化，再分解，产生更多甲烷，等等。 如此往复循环。

youdao

It appears to be still deep frozen under a surface of ice, cracking and thawing.

这似乎是下仍然深度冷冻的冰面，有开裂和融化。

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Rain and thawing snow could cause localised flooding and surface water on roads and fields, it said.

BBC: Wales weather: Floods possible as heavy rain forecast