CH4 abundance (ppb)
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year RCP8.5 RCP6.0 RCP4.5 RCP2.6
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2000   1751   1751   1751   1751
2010   1779   1769   1767   1773
2020   1924   1786   1801   1731
2030   2132   1796   1830   1600
2040   2399   1841   1842   1527
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