图观天下

pace, Sea ice in the Arctic is melting at a record speeding expected melting suggesting warming at the north pole is up and a largely ice-free Arctic can be in summer months within 30 years. Arctic Circle ice drives Polar Bears The closer

北极区的海冰正以创纪录的速度融化，表明北极的升温在加速，且预期在30年内的夏季月份北极大部分地区将出现无冰状态。融化的北极冰迫使北极熊面临灭绝。

Curiosity is not the only spacecraft currently wandering over Mars--Opportunity is still going strong, more than eight years after it touched down on the planet. Opportunity sent back a series of fascinating pictures of the landscape around it recently.