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NASA Animation: Watching the Earth Breathe

By Climate Central

Watch the Earth Breathe

When Charles Keeling first began measuring the atmosphere’s carbon dioxide levels in the late 1950’s, he noted first that they stood at about 315 parts per million (ppm), or 315 molecules of carbon dioxide for every million molecules of air.

Soon after, though, he found that the concentrations were rising, thanks to the burning of fossil fuels (today, they stand at around 395 ppm and they’re still rising). But he also noticed that the upward curve of CO2 concentrations had a sawtooth pattern. That pattern saw CO2 rise sharply in the fall in the Northern Hemisphere -- when leaves died and fell off the trees to rot -- then drop slightly in spring as new leaves emerged to start drawing in CO2 for photosynthesis. (Leaves fall and sprout in the Southern Hemisphere, too, in an exactly opposite pattern, but there’s so much more ocean and so much less land south of the Equator that the Northern effect is a lot stronger).

Now NASA has put together an animation that shows this process in a much more vivid way. Based on observations from two instruments on the Aqua spacecraft, the animation shows how the disappearance of leaves (green) leads to an increase in atmospheric CO2 (yellow-orange), first in one hemisphere, then in the other — and just as Keeling showed a half-century ago, the effect in the Northern Hemisphere is a lot stronger.

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Comments

By Cab Hatfield (New York, NY 10002)
on July 22nd, 2012

Couldn’t help but notice that big blank area of the Sahara in the middle of the map. Has anyone calculated the impact on global CO2 if that area had vegetation?

Reply to this comment

By TPagano (Newbury Park, CA 91320)
on February 12th, 2013

The “Watching the Earth Breath” animation was developed by NASA using measured data from its NASA Aqua Satellite.  Land vegetation is in green as measured by MODIS and carbon dioxide is in orange as measured by AIRS.  In the winter months, the vegetation dies off and the carbon dioxide levels build up.  In the summer months the vegetation blooms and draws down the carbon dioxide from the atmosphere.  This can be seen particularly well in the boreal forests of Asia and North America.  At least two scientists currently attribute the reduced concentrations in the equatorial region primarily due to a strong downwelling branch of the Walker Circulation, bringing older, lower concentrations of carbon dioxide from the stratosphere into the mid troposphere where the AIRS senses the carbon dioxide.  The animation cuts off below 60 degrees due to issues with the current retrieval, but we are expected to improve that in the next version.  See http://airs.jpl.nasa.gov/news_archive/2012-06-29-co2-and-vegetation/

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