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 Atmospheric Carbon Dioxide Records from Mauna Loa, Hawaii (1958–2000)

Carbon dioxide in the atmosphere traps heat and warms the earth’s surface. (Other greenhouse gases also trap heat, as do clouds.) This graph presents measurements of carbon dioxide concentration in the atmosphere over the last half of the twentieth century.

These measurements represent continuous air samples taken at a lava field near Hawaii’s lofty Mauna Loa volcano. Mauna Loa’s remoteness makes it an exceptionally good spot to take such measurements, because influences of vegetation or human activity on the amount of carbon dioxide are minimal. Additionally, any atmospheric change due to volcanic eruptions can be measured and subtracted from the observations. And the time carbon dioxide stays in the atmosphere (around one hundred years) allows winds to mix the air from sources worldwide. That’s why these measurements are considered a reliable index of carbon dioxide concentration in the mid-atmosphere.

These measurements break down one million units of sampled air into the portions that do and do not contain carbon dioxide. The graph shows a 17% increase in carbon dioxide concentrations from 1959 ( about 316 parts per million by volume) to 2000 (about 369 ppmv).



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Atmospheric Carbon Dioxide Records from Mauna Loa, Hawaii (1958–2000)

Atmospheric Carbon Dioxide Records from Mauna Loa, Hawaii (1958–2000) This graph shows changes in the atmospheric concentration of carbon dioxide from 1958 to 2000. Source: Carbon Dioxide Information Analysis Center


 questions about the data  

question Why is measuring carbon dioxide in the atmosphere so important in understanding global climate change?

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 research connection  

Any measurement can be contaminated by factors that aren’t relevant to what scientists are really interested in. For example, researchers trying to obtain a background index of carbon dioxide in the air wouldn’t want to take measurements where carbon dioxide is unusually high or low, like in a city (where human activity might make local carbon dioxide concentrations artificially high) or a forest (where trees would consume some of the carbon dioxide in the air).


 related sites  

Carbon Dioxide Information Analysis Center - Information on carbon dioxide and climate change.

CO2 Science Magazine - Up-to-date research on the role of carbon dioxide in climate.

EPA Global Warming: Carbon Dioxide Emissions - Information about sources of CO2 and the global carbon cycle.

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