E-Mail IMAGE: The authors of this study: Dr. Christopher Reinhard (left) and Dr. Kazumi Ozaki (right). view more Credit: Kazumi Ozaki Earth's surface environments are highly oxygenated - from the atmosphere to the deepest reaches of the oceans, representing a hallmark of active photosynthetic biosphere. However, the fundamental timescale of the oxygen-rich atmosphere on Earth remains uncertain, particularly for the distant future. Solving this question has great ramifications not only for the future of Earth's biosphere but for the search for life on Earth-like planets beyond the solar system. A new study published in Nature Geoscience this week tackles this problem using a numerical model of biogeochemistry and climate and reveals that the future lifespan of Earth's oxygen-rich atmosphere is approximately one billion years.