Video Transcript: Watching Earth Breathe: the Seasonal Vegetation Cycle and Carbon Dioxide

Carbon dioxide is a naturally occurring gas in our atmosphere and monitoring it is like watching our planet breathe.

This animation shows the seasonal cycle of carbon dioxide and the increase of carbon dioxide every year due to human activity. In photosynthesis, plants absorb sunlight and carbon dioxide to make oxygen. And what's known as respiration, plants produce small amounts of carbon dioxide that is released back into the atmosphere.

When we burn coal and fossil fuels lots of carbon dioxide is released into the atmosphere.

Carbon dioxide is also a greenhouse gas, which traps infrared radiation and helps keep the planet warm enough for human life.

NASA's Atmospheric Infrared Sounder instrument, or AIRS, is an instrument onboard NASA's Earth orbiting satellite called Aqua.

AIRS can measure the concentration of the carbon dioxide in the middle of the atmosphere around the entire globe every day.

In this animation, orange represents carbon dioxide as measured by AIRS, green represents the concentration of vegetation, measured by another instrument on the Aqua satellite called MODIS.

Here we've taken out human sources of carbon dioxide to see the natural cycle of the gas as it's affected by the seasonal photosynthesis and respiration of trees and plants around the globe.

Carbon dioxide builds up in the northern hemisphere during the winter months, when trees and plants are losing their leaves.

And in the summer when greening occurs, plants through the process of photosynthesis absorb the carbon dioxide from the atmosphere.

This process can be seen particularly well in the Boreal forest of Asia and North America located in the northern regions of these continents.

This is the first direct observation from satellite instruments of the "breathing" of the global biosphere.