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  2. Geological history of oxygen - Wikipedia

    en.wikipedia.org/wiki/Geological_history_of_oxygen

    The increase in oxygen concentrations had wide ranging and significant impacts on Earth's biosphere. Most significantly, the rise of oxygen and the oxidative depletion of greenhouse gases (especially atmospheric methane ) due to the GOE led to an icehouse Earth that caused a mass extinction of anaerobic microbes , but paved the way for the ...

  3. Atmosphere of Earth - Wikipedia

    en.wikipedia.org/wiki/Atmosphere_of_Earth

    Air also contains a variable amount of water vapor, on average around 1% at sea level, and 0.4% over the entire atmosphere. Earth's early atmosphere consisted of accreted gases from the solar nebula , but the atmosphere changed significantly over time, affected by many factors such as volcanism , impact events , weathering and the evolution of ...

  4. Great Oxidation Event - Wikipedia

    en.wikipedia.org/wiki/Great_Oxidation_Event

    The Great Oxidation Event (GOE) or Great Oxygenation Event, also called the Oxygen Catastrophe, Oxygen Revolution, Oxygen Crisis or Oxygen Holocaust, [2] was a time interval during the Earth's Paleoproterozoic era when the Earth's atmosphere and shallow seas first experienced a rise in the concentration of free oxygen. [3]

  5. Neoproterozoic oxygenation event - Wikipedia

    en.wikipedia.org/wiki/Neoproterozoic_oxygenation...

    The evolution and radiation of nitrogen-fixing bacteria and non-nitrogen-fixing picocyanobacteria capable of occupying marine planktonic niches and consequent changes to the nitrogen cycle during the Cryogenian are believed to be a culprit behind the rapid oxygenation of and removal of carbon dioxide from the atmosphere, which also helps ...

  6. Why air quality is worse when it's really hot - AOL

    www.aol.com/news/why-air-quality-worse-really...

    The higher the level of air pollution the more hazardous it is for your health. You can find the current AQI for your area by typing in your zip code at AirNow.gov. ... Nitrogen dioxide.

  7. Nitrogen cycle - Wikipedia

    en.wikipedia.org/wiki/Nitrogen_cycle

    Increasing levels of nitrogen deposition is shown to have several adverse effects on both terrestrial and aquatic ecosystems. [52] [53] Nitrogen gases and aerosols can be directly toxic to certain plant species, affecting the aboveground physiology and growth of plants near large point sources of nitrogen pollution. Changes to plant species may ...

  8. Human impact on the nitrogen cycle - Wikipedia

    en.wikipedia.org/wiki/Human_impact_on_the...

    Additionally, there was a reported fourfold increase in riverine dissolved inorganic N fluxes to coasts. [6] Nitrogen is a critical limiting nutrient in many systems, including forests, wetlands, and coastal and marine ecosystems; therefore, this change in emissions and distribution of Nr has resulted in substantial consequences for aquatic and ...

  9. Nitrogen - Wikipedia

    en.wikipedia.org/wiki/Nitrogen

    Nitrogen is a chemical element; it has symbol N and atomic number 7. Nitrogen is a nonmetal and the lightest member of group 15 of the periodic table, often called the pnictogens. It is a common element in the universe, estimated at seventh in total abundance in the Milky Way and the Solar System.