H₂ in Antarctic firn air: Atmospheric reconstructions and implications for anthropogenic emissions.

ABSTRACT: The atmospheric history of molecular hydrogen (H₂) from 1852 to 2003 was reconstructed from measurements of firn air collected at Megadunes, Antarctica. The reconstruction shows that H₂ levels in the southern hemisphere were roughly constant near 330 parts per billion (ppb; nmol H₂ mol^-1 air) during the mid to late 1800s. Over the twentieth century, H₂ levels rose by about 70% to 550 ppb. The reconstruction shows good agreement with the H₂ atmospheric history based on firn air measurements from the South Pole. The broad trends in atmospheric H₂ over the twentieth century can be explained by increased methane oxidation and anthropogenic emissions. The H₂ rise shows no evidence of deceleration during the

SUBMITTER: Patterson JD 

PROVIDER: S-EPMC8433534 | biostudies-literature | 2021 Sep

REPOSITORIES: biostudies-literature