Snow and ice emit microwaves, but the signal is different for wet, melting snow than for dry.

雪和冰都放射微波，但潮湿、融化的雪放射的微波信号与未融化的雪不同。

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This lava field just north of the Mýrdalsjökull ice cap serves as one of many monitoring sites to track ground deformation that could serve as a signal of an impending eruption of Katla.

这片位于米达尔斯冰盖北部的熔岩原是用来追踪地面形变的监测点之一，这里地面的形变可以被视为卡特拉火山喷发的前兆。

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There are glimpses of blue-green ice within the fissures, but the cracks themselves signal trouble.

在石块的裂隙中可以看到一些蓝绿色的冰块，然而这些裂隙本身就预示着麻烦。

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Researchers were amazed at the strength of the signal of the ice.

BBC: Ice reservoirs found on Mars

Prof Laxon solved the problem of separating ice from water in the satellite altimeter signal.

BBC: Cryosat spots Arctic sea-ice loss in autumn

Taipei's Want Daily is already welcoming "ice-breaking expert" Mr Wang's rumoured promotion as Beijing's "signal of peace" for improved relations with Japan and the outside world.

BBC: China media: NPC spokeswoman praised