1
00:00:00,020 --> 00:00:04,080
NASA’s DC-8 is on its second tour to survey the world’s atmosphere. 

2
00:00:04,080 --> 00:00:08,260
Scientists on the ATom mission are looking for changes in atmospheric gases

3
00:00:08,260 --> 00:00:12,330
that occur due to the seasons.

4
00:00:12,330 --> 00:00:16,350
First stop: Alaska.

5
00:00:16,350 --> 00:00:20,490
Last summer, evidence of Siberian fires was in the air.

6
00:00:20,490 --> 00:00:24,600
This winter, pollution from Asia dominated.

7
00:00:24,600 --> 00:00:28,780
Out the window, the team observed our changing planet. 

8
00:00:28,780 --> 00:00:35,269
The sea ice appeared much thinner than is usual for this time of year.