When scientists analyzed air samples trapped in drilled cores of Antarctica's ice, they found atmospheric hydrogen had increased 70 percent over the course of the 20th century.
Even as recent air pollution laws have sought to curb fossil fuel emissions, hydrogen emissions have continued to rise with no signs of slowing down. There's a chance that leakage is to blame.
Molecular hydrogen is a natural component of our atmosphere due to the breakdown of formaldehyde, but it is also a byproduct of fossil fuel combustion, especially from automobile exhaust and biomass burning.
While hydrogen doesn't trap heat in the atmosphere on its own, it can indirectly impact the distribution of methane and ozone. After carbon dioxide, these are the two most important greenhouse gases, which means global hydrogen levels can also perturb the climate.
Nevertheless, the sources and sinks of atmospheric hydrogen are rarely studied. We don't even have a good estimate of how much humans have emitted since industrial times.
The current study is the first to offer up a solid figure. Between 1852 and 2003, air samples from near the South Pole of Antarctica suggest atmospheric hydrogen jumped from 330 parts per billion to 550 parts per billion.
"Aging air is trapped in the perennial snowpack above an ice sheet, and sampling it gives us a highly accurate account of atmospheric composition over time," explains Earth scientist John Patterson from the University of California Irvine. READ MORE
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