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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

    By mole fraction (i.e., by quantity of molecules), dry air contains 78.08% nitrogen, 20.95% oxygen, 0.93% argon, 0.04% carbon dioxide, and small amounts of other trace gases (see Composition below for more detail). Air also contains a variable amount of water vapor, on average around 1% at sea level, and 0.4% over the entire atmosphere.

  4. 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 ...

  5. 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.

  6. 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.

  7. 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]

  8. Decompression theory - Wikipedia

    en.wikipedia.org/wiki/Decompression_theory

    Atmospheric nitrogen has a partial pressure of approximately 0.78 bar at sea level. Air in the alveoli of the lungs is diluted by saturated water vapour (H 2 O) and carbon dioxide (CO 2), a metabolic product given off by the blood, and contains less oxygen (O 2) than atmospheric air as some of it is taken up by the blood for metabolic use. The ...

  9. Heat-trapping carbon dioxide and methane levels in the air ...

    www.aol.com/news/heat-trapping-carbon-dioxide...

    The 2.8 parts per million increase in carbon dioxide airborne levels from January 2023 to December, wasn't as high as the jumps were in 2014 and 2015, but they were larger than every other year ...