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Our Atmosphere Is Leaking Oxygen and Scientists Don't Know Why (gizmodo.com)

The Earth's atmosphere has been leaking oxygen and scientists don't know why. Researchers discovered that over the past 800,000 years, atmospheric oxygen levels have dropped by 0.7 percent. How exactly did they discover the leak? By observing ice cores from Greenland and Antarctica, which contain trapped air bubbles representing snapshots of our atmosphere over the past million-odd years. Gizmodo reports: By examining the ratio of oxygen to nitrogen isotopes within these cores, the researchers were able to pull out a trend: oxygen levels have fallen by 0.7 percent over the past 800,000 years, meaning sinks are roughly 2 percent larger than sources. Writing today in Science, the researchers offer a few possible explanations. For one, erosion rates appear to have sped up in recent geologic history, causing more fresh sediment to be exposed and oxidized by the atmosphere, causing more oxygen to be consumed. Long-term climate change could also be responsible. Recent human-induced warming aside, our planet's average temperature had been declining a bit over the past few million years. [Princeton University geologist Daniel Stolper] added that there could be other explanations, too, and figuring out which is correct could prove quite challenging. But learning what controls the knobs in our planet's oxygen cycle is worth the effort. It could help us understand what makes a planet habitable at all -- something scientists are rather keen on, given recent exoplanet discoveries. Stolper's analysis excluded one very unusual part of the record: the last 200 years of industrial human society. "We are consuming O2 at a rate a factor of a thousand times faster than before," Stolper said. "Humankind has completely short-circuited the cycle by burning tons of carbon."

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  1. OMG by matushorvath · · Score: 1, Redundant

    Oxygen levels can't go up, where would the oxygen come from? It's very improbable that oxygen levels stay the same, over time nothing stays the same in nature. The only remaining option is that oxygen levels go down. Problem solved.