A new indicator of ancient CO2-levels, using the organic molecule phytane, has been developed providing the most continuous record of CO2-concentrations ever. The data show that present rises in CO2-levels that used to take millions of years, are now happening in a century.

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A new indicator of ancient CO2-levels, using the organic molecule phytane, has been developed providing the most continuous record of CO2-concentrations ever. The data show that present rises in CO2-levels that used to take millions of years, are now happening in a century.