polar indicator

例句：

1. 1.The scientist used a polar indicator to measure the temperature at the poles.
   科学家使用一个极地指示器来测量极地的温度。
2. 2.The polar indicator showed that the ice was melting at an alarming rate.
   极地指示器显示，冰正在以令人担忧的速度融化。
3. 3. The polar indicator data helped scientists predict the impact of climate change on the Arctic region.
   极地指示器数据帮助科学家预测气候变化对北极地区的影响。