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Hi, this is Bill Putman. I'm a climate scientist at NASA's Goddard Space Flight Center.

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What you’re looking at is a supercomputer model of carbon dioxide levels in the Earth’s atmosphere.

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The visualization compresses one year of data into a few minutes.

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Carbon dioxide is the most important greenhouse gas affected by human activity.

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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.

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In the Northern Hemisphere, we see the highest concentrations are focused around major emission sources over North America, Europe and Asia.

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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.

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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.

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We see this change in the model as the red and purple colors start to fade.

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Meanwhile, in the Southern Hemisphere, we see the release of another pollutant—carbon monoxide.

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This is a gas that’s both harmful to the environment and to humans.

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During the summer months, plumes of carbon monoxide stream from fires in Africa, South America and Australia, contributing to high concentrations in the atmosphere.

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Notice how these emissions are also transported by winds to other parts of the world.

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As summer transitions to fall, and plant photosynthesis decreases, carbon dioxide begins to accumulate in the atmosphere.

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Although this change is expected, we’re seeing higher concentrations of carbon dioxide accumulate in the atmosphere each year.

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This is contributing to the long-term trend of rising global temperatures.

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The Orbiting Carbon Observatory-2, or OCO-2, will be the first NASA satellite mission to provide a global view of carbon dioxide.

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OCO-2 observations and atmospheric models like GEOS-5 will work closely together to better understand both human emissions and natural fluxes of carbon dioxide.

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This will help guide climate models toward more reliable predictions of future conditions across the globe.

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