1 00:00:01,150 --> 00:00:06,900 Hi, this is Bill Putman. I'm a climate scientist at NASA's Goddard Space Flight Center. 2 00:00:06,950 --> 00:00:12,680 What you’re looking at is a supercomputer model of carbon dioxide levels in the Earth’s atmosphere. 3 00:00:13,630 --> 00:00:17,510 The visualization compresses one year of data into a few minutes. 4 00:00:20,000 --> 00:00:24,880 Carbon dioxide is the most important greenhouse gas affected by human activity. 5 00:00:25,000 --> 00:00:34,840 About half of the carbon dioxide emitted from fossil fuel combustion remains in the atmosphere, while the other half is absorbed by natural land and ocean reservoirs. 6 00:00:36,600 --> 00:00:44,930 In the Northern Hemisphere, we see the highest concentrations are focused around major emission sources over North America, Europe and Asia. 7 00:00:46,500 --> 00:00:55,570 Notice how the gas doesn’t stay in one place. The dispersion of carbon dioxide is controlled by the large-scale weather patterns within the global circulation. 8 00:01:02,000 --> 00:01:12,140 During spring and summer in the Northern Hemisphere, plants absorb a substantial amount of carbon dioxide through photosynthesis, thus removing some of the gas from the atmosphere. 9 00:01:13,000 --> 00:01:16,940 We see this change in the model as the red and purple colors start to fade. 10 00:01:32,000 --> 00:01:37,570 Meanwhile, in the Southern Hemisphere, we see the release of another pollutant—carbon monoxide. 11 00:01:37,860 --> 00:01:41,200 This is a gas that’s both harmful to the environment and to humans. 12 00:01:42,000 --> 00:01:51,480 During the summer months, plumes of carbon monoxide stream from fires in Africa, South America and Australia, contributing to high concentrations in the atmosphere. 13 00:01:53,500 --> 00:01:58,360 Notice how these emissions are also transported by winds to other parts of the world. 14 00:02:07,000 --> 00:02:14,780 As summer transitions to fall, and plant photosynthesis decreases, carbon dioxide begins to accumulate in the atmosphere. 15 00:02:16,300 --> 00:02:23,410 Although this change is expected, we’re seeing higher concentrations of carbon dioxide accumulate in the atmosphere each year. 16 00:02:24,000 --> 00:02:28,020 This is contributing to the long-term trend of rising global temperatures. 17 00:02:32,000 --> 00:02:41,540 The Orbiting Carbon Observatory-2, or OCO-2, will be the first NASA satellite mission to provide a global view of carbon dioxide.