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  2. Dynastic cycle - Wikipedia

    en.wikipedia.org/wiki/Dynastic_cycle

    Dynastic cycle (traditional Chinese: 朝代循環; simplified Chinese: 朝代循环; pinyin: Cháodài Xúnhuán) is an important political theory in Chinese history. According to this theory, each dynasty of China rises to a political, cultural, and economic peak and then, because of moral corruption, declines, loses the Mandate of Heaven ...

  3. Marine biogeochemical cycles - Wikipedia

    en.wikipedia.org/wiki/Marine_biogeochemical_cycles

    Since liquid water flows, ocean waters cycle and flow in currents around the world. Since water easily changes phase, it can be carried into the atmosphere as water vapour or frozen as an iceberg. It can then precipitate or melt to become liquid water again. All marine life is immersed in water, the matrix and womb of life itself. [7]

  4. Deep water cycle - Wikipedia

    en.wikipedia.org/wiki/Deep_water_cycle

    Water carried into the mantle eventually returns to the surface in eruptions at mid-ocean ridges and hotspots. [8] This circulation of water into the mantle and back is known as the deep water cycle or the geologic water cycle. [9] [10] [11] [5] Estimates of the amount of water in the mantle range from 1 ⁄ 4 to 4 times the water in the ocean ...

  5. Water cycle - Wikipedia

    en.wikipedia.org/wiki/Water_cycle

    The ocean plays a key role in the water cycle as it is the source of 86% of global evaporation. [2] The water cycle involves the exchange of energy, which leads to temperature changes. When water evaporates, it takes up energy from its surroundings and cools the environment. When it condenses, it releases energy and warms the environment.

  6. Timeline of natural history - Wikipedia

    en.wikipedia.org/wiki/Timeline_of_natural_history

    The Ca-Al-rich inclusions, which formed 2 million years before the chondrules, [1] are a key signature of a supernova explosion. c. 4,567 ±3 Ma – Rapid collapse of hydrogen molecular cloud , forming a third-generation Population I star , the Sun , in a region of the Galactic Habitable Zone (GHZ), about 25,000 light years from the center of ...

  7. Ancient maritime history - Wikipedia

    en.wikipedia.org/wiki/Ancient_maritime_history

    The Bronze Age boat which is about 9.5 meters long × 2.3 meters wide is believed to have been a seagoing vessel. Carbon dating reveals that the craft dating from approximately 1600 BC might be the oldest known sea-going boat. The hull was of half oak logs and side panels also of oak were stitched on with yew lashings.

  8. Messinian salinity crisis - Wikipedia

    en.wikipedia.org/wiki/Messinian_salinity_crisis

    In the Messinian salinity crisis (also referred to as the Messinian event, and in its latest stage as the Lago Mare event) the Mediterranean Sea went into a cycle of partial or nearly complete desiccation (drying-up) throughout the latter part of the Messinian age of the Miocene epoch, from 5.96 to 5.33 Ma (million years ago).

  9. Younger Dryas - Wikipedia

    en.wikipedia.org/wiki/Younger_Dryas

    The Younger Dryas (YD, Greenland Stadial GS-1) [2] was a period in Earth's geologic history that occurred circa 12,900 to 11,700 years Before Present (BP). [3] It is primarily known for the sudden or "abrupt" cooling in the Northern Hemisphere, when the North Atlantic Ocean cooled and annual air temperatures decreased by ~3 °C (5.4 °F) over North America, 2–6 °C (3.6–10.8 °F) in Europe ...