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  2. Atmosphere of Earth - Wikipedia

    en.wikipedia.org/wiki/Atmosphere_of_Earth

    Composition of Earth's atmosphere by molecular count, excluding water vapor. Lower pie represents trace gases that together compose about 0.0434% of the atmosphere (0.0442% at August 2021 concentrations [5] [6]). Numbers are mainly from 2000, with CO 2 and methane from 2019, and do not represent any single source. [7]

  3. Paleoatmosphere - Wikipedia

    en.wikipedia.org/wiki/Paleoatmosphere

    A paleoatmosphere (or palaeoatmosphere) is an atmosphere, particularly that of Earth, at some unspecified time in the geological past.. When regarding geological history of Earth, the paleoatmosphere can be chronologically divided into the Hadean first atmosphere, which resembled the compositions of the solar nebula; the Archean second atmosphere (also known as the prebiotic atmosphere), which ...

  4. File:Atmosphere gas proportions.svg - Wikipedia

    en.wikipedia.org/wiki/File:Atmosphere_gas...

    English: Gas proportions in the Earth's atmosphere. The proportion of water vapor (H₂O) is variable so it is not represented in this chart, however it averages about 1% in the troposphere . Deutsch: Volumenanteil der Gase in der Luft

  5. Paleoclimatology - Wikipedia

    en.wikipedia.org/wiki/Paleoclimatology

    About 3.4 billion years ago, nitrogen was the major part of the then stable "second atmosphere". An influence of life has to be taken into account rather soon in the history of the atmosphere because hints of early life forms have been dated to as early as 3.5 to 4.3 billion years ago. [21]

  6. Atmosphere of Venus - Wikipedia

    en.wikipedia.org/wiki/Atmosphere_of_Venus

    The early Earth during the Hadean eon is believed by most scientists to have had a Venus-like atmosphere, with roughly 100 bar of CO 2 and a surface temperature of 230 °C, and possibly even sulfuric acid clouds, until about 4.0 billion years ago, by which time plate tectonics were in full force and together with the early water oceans, removed ...

  7. Great Oxidation Event - Wikipedia

    en.wikipedia.org/wiki/Great_Oxidation_Event

    4, which is a powerful greenhouse gas and was produced by early forms of life known as methanogens. Scientists continue to research how the Earth was warmed before life arose. [15] An atmosphere of N 2 and CO 2 with trace amounts of H 2 O, CH 4, carbon monoxide (CO), and hydrogen (H 2) is described as a weakly reducing atmosphere. [16]

  8. THE END - HuffPost

    images.huffingtonpost.com/2007-09-10-EOA...

    that “they” should manage our rights, the way we hire a professional to do our taxes; “they” should run the government, create policy, worry about whether democracy is up and running.

  9. Geological history of oxygen - Wikipedia

    en.wikipedia.org/wiki/Geological_history_of_oxygen

    O 2 build-up in the Earth's atmosphere. Red and green lines represent the range of the estimates while time is measured in billions of years ago . Stage 1 (3.85–2.45 Ga): Practically no O 2 in the atmosphere. Stage 2 (2.45–1.85 Ga): O 2 produced, but absorbed in oceans and seabed rock.