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  2. Ozone–oxygen cycle - Wikipedia

    en.wikipedia.org/wiki/Ozone–oxygen_cycle

    Most of the ozone production occurs in the tropical upper stratosphere and mesosphere. The total mass of ozone produced per day over the globe is about 400 million metric tons. The global mass of ozone is relatively constant at about 3 billion metric tons, meaning the Sun produces about 12% of the ozone layer each day. [1]

  3. Ozone layer - Wikipedia

    en.wikipedia.org/wiki/Ozone_layer

    Ozone-oxygen cycle in the ozone layer. The photochemical mechanisms that give rise to the ozone layer were discovered by the British physicist Sydney Chapman in 1930. Ozone in the Earth's stratosphere is created by ultraviolet light striking ordinary oxygen molecules containing two oxygen atoms (O 2), splitting them into individual oxygen atoms (atomic oxygen); the atomic oxygen then combines ...

  4. Ground-level ozone - Wikipedia

    en.wikipedia.org/wiki/Ground-level_ozone

    Ground-level ozone (O 3), also known as surface-level ozone and tropospheric ozone, is a trace gas in the troposphere (the lowest level of the Earth's atmosphere), with an average concentration of 20–30 parts per billion by volume (ppbv), with close to 100 ppbv in polluted areas.

  5. Ozone - Wikipedia

    en.wikipedia.org/wiki/Ozone

    Fluctuations in ambient air, due to weather or other environmental conditions, cause variability in ozone production. However, they also produce nitrogen oxides as a by-product. Use of an air dryer can reduce or eliminate nitric acid formation by removing water vapor and increase ozone production. At room temperature, nitric acid will form into ...

  6. Tropospheric ozone depletion events - Wikipedia

    en.wikipedia.org/wiki/Tropospheric_ozone...

    Ozone in the troposhere is determined by photochemical production and destruction, dry deposition and cross-tropopause transport of ozone from the stratosphere. [2] In the Arctic troposphere, transport and photochemical reactions involving nitrogen oxides and volatile organic compounds (VOCs) as a result of human emissions also produce ozone resulting in a background mixing ratio of 30 to 50 ...

  7. Geological history of oxygen - Wikipedia

    en.wikipedia.org/wiki/Geological_history_of_oxygen

    At current rates of primary production, today's concentration of oxygen could be produced by photosynthetic organisms in 2,000 years. [4] In the absence of plants, the rate of oxygen production by photosynthesis was slower in the Precambrian, and the concentrations of O 2 attained were less than 10% of today's and probably fluctuated greatly.

  8. Oxygen cycle - Wikipedia

    en.wikipedia.org/wiki/Oxygen_cycle

    While there are many abiotic sources and sinks for O 2, the presence of the profuse concentration of free oxygen in modern Earth's atmosphere and ocean is attributed to O 2 production from the biological process of oxygenic photosynthesis in conjunction with a biological sink known as the biological pump and a geologic process of carbon burial involving plate tectonics.

  9. Photodissociation - Wikipedia

    en.wikipedia.org/wiki/Photodissociation

    is a key reaction in the formation of tropospheric ozone. [16] The formation of the ozone layer is also caused by photodissociation. Ozone in the Earth's stratosphere is created by ultraviolet light striking oxygen molecules containing two oxygen atoms (O 2), splitting them into individual oxygen atoms (atomic oxygen). The atomic oxygen then ...