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Knowledge of precise climatic events decreases as the record goes further back in time. The timeline of glaciation covers ice ages specifically, which tend to have their own names for phases, often with different names used for different parts of the world. The names for earlier periods and events come from geology and paleontology.
In the Northern Hemisphere, they take the form of rapid warming episodes, typically in a matter of decades, each followed by gradual cooling over a longer period.For example, about 11,500 years ago, averaged annual temperatures on the Greenland ice sheet increased by around 8 °C over 40 years, in three steps of five years, [3] where a 5 °C change over 30–40 years is more common. [4]
A less severe cold period or ice age is shown during the Jurassic-Cretaceous (150 Ma). There have been five or six major ice ages in the history of Earth over the past 3 billion years. The Late Cenozoic Ice Age began 34 million years ago, its latest phase being the Quaternary glaciation, in progress since 2.58 million years ago.
There is controversy over whether these glaciations indeed covered the entire planet, or whether a band of open sea survived near the equator (i.e. "slushball Earth"), but the extreme climates with massive expanse of ice sheets blocking off sunlight would nevertheless have significantly hindered primary production in the shallow seas and caused ...
A glacial period (alternatively glacial or glaciation) is an interval of time (thousands of years) within an ice age that is marked by colder temperatures and glacier advances. Interglacials, on the other hand, are periods of warmer climate between glacial periods. The Last Glacial Period ended about 15,000 years ago. [1]
A chronology of climatic events of importance for the Last Glacial Period, about the last 120,000 years The Last Glacial Period caused a much lower global sea level.. The Last Glacial Period (LGP), also known as the Last glacial cycle, occurred from the end of the Last Interglacial to the beginning of the Holocene, c. 115,000 – c. 11,700 years ago, and thus corresponds to most of the ...
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End of Marinoan Glaciation: last major "snowball Earth" event as future ice ages will feature less overall ice coverage of the planet; c. 633 Ma – Beardmore Orogeny (to c. 620 Ma) in Antarctica: reflection of final break-up of Rodinia as pieces of the supercontinent begin moving together again to form Pannotia