The atmosphere is not the only reservoir for civilization's emissions of carbon. This page brings the oceans into the picture. Over longer time scales, most of the carbn emitted today will end up in the ocean.
Ocean Acidification: Explained in 60 seconds
Hawaii CO2 in the Atmosphere and Ocean
Ocean Perspective on the Global Carbon Cycle
The "airborne fraction" tells us that most of CO2 emissions into the atmosphere stay in the atmosphere for a long time. But the atmosphere is a small reservoire for carbon. About 16 times more carbon is stored on land ("terrestrial biosphere"). And about 60 times more carbon is stored in the ocean (in pre-industrial times before the drastic increases in atmospheric emissions). The ocean takes the most carbon, but the rate of carbon uptake is slower. The trend we see today in the ocean will long outlast the trend we see in the atmosphere.
At present, just a quarter of CO2 emissions into the atmosphere are absorbed by the oceans. CO2 in the air reacts with seawater and forms carbonic acid that acidifies the ocean. As acidification increases, pH falls. Since pre-industrial times, the average pH of ocean surface water fell from 8.21 to 8.10. As a logarithmic scale, this change equates to a 30 percent increase in acidity. At the current rate, pH could decrease another 0.3 pH units. This would make the ocean more acidic than any time in the past 100 million years. This is a dangerous trends because it is more difficult for shellfish to live, as well as plankton at the base of the ocean food web.
What does this mean? It means there are many earth systems that interact over relatively short and long time scales that affect and sustain life in the biosphere. There is a need to think about global environmental change with the aim of returning stability to the system as a whole. Approaches like geoengineering can provide temporary relief to undesirable effects of some changes--like warming temperatures on the earth's surface. But larger issues remain to be seen and addressed.
NOAA-NCEI Ocean climate laboratory
NOAA-NCEI World Ocean Database (WOD)
NOAA-ESRL About the world ocean database
NOAA PMEL Ocean acidification observations & data
Links for Deeper Exploration
Ocean carbon cycle
NOAA PMEL A primer on pH
NOAA PMEL What is ocean acidification?
IGBP 2012 Ocean in a high CO2 world
NOAA PMEL Ocean acidification educational tools
NOAA PMEL Sampling educational tools
NOAA PMEL Carbon educational tools
NOAA PMEL Carbon cycles in coastal oceans
NOAA PMEL OA Links
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