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A glacial period is an interval of time within an ice age that is marked by colder temperatures and glacier advances. An ice age is a period of long-term reduction in the Temperature of the Earth 's surface and atmosphere resulting in an expansion of continental Ice sheets "Glacial" and "Glaciation" redirect here For the geological periods see Glacial period. Interglacials, on the other hand, are periods of warmer climate within an ice age. An interglacial is a geological interval of warmer global average temperature that separates Glacial periods within an Ice age. The last glacial period ended about 10,000 to 15,000 years ago; the current Holocene epoch is the interglacial we are presently in. "Last glacial" redirects here For the period of maximum glacier extent during this time see Last Glacial Maximum The last glacial period The Holocene is a Geological epoch which began approximately 10000 years ago (about 8000 BC

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Quaternary ice age

Main articles: Quaternary glaciation and timeline of glaciation
Glacial and interglacial cycles of the late Pleistocene epoch within the Quaternary glaciation, as represented by atmospheric CO2, measured from ice core samples going back 650,000 years
Glacial and interglacial cycles of the late Pleistocene epoch within the Quaternary glaciation, as represented by atmospheric CO2, measured from ice core samples going back 650,000 years

Within the Quaternary glaciation (2. There have been four major periods of glaciation in the Earth's past The Pleistocene ('plaɪstəsin is the epoch from 18 million to 10000 years BP covering the world's recent period Carbon dioxide ( Chemical formula:) is a Chemical compound composed of two Oxygen Atoms covalently bonded to a single An ice core is a Core sample from the accumulation of snow and ice over many years that have re-crystallized and have trapped air bubbles from previous time periods Overview The term Quaternary ("fourth" was proposed by Giovanni Arduino in 1759 for alluvial deposits in the Po river valley in northern 58 Ma to present), there have been various glacials and interglacials. Annum is one form of the Latin noun meaning Year, not a form normally used for derivatives in modern languages the accusative singular

Within the Pleistocene extent of the Quaternary ice age, there have been the following glacials and interglacials, from earliest to latest:

Last glacial period

Main article: Last glacial period

The last glacial period was the most recent glacial period within the current ice age, occurring in the Pleistocene epoch, which began about 70,000 and ended between 10,000 and 15,000 Before Present (BP). The Pleistocene ('plaɪstəsin is the epoch from 18 million to 10000 years BP covering the world's recent period The Beestonian Stage is the name for an early Pleistocene stage used in the British Isles. The Kansan Glaciation (known in the UK as the Anglian glaciation, Elster glaciation in northern Europe and the Mindel glaciation in the The Eemian interglacial era, now known as the Eemian Stage is temporally equivalent to the Sangamon Stage in North America, the Ipswichian Stage in "Last glacial" redirects here For the period of maximum glacier extent during this time see Last Glacial Maximum The last glacial period "Last glacial" redirects here For the period of maximum glacier extent during this time see Last Glacial Maximum The last glacial period The Pleistocene ('plaɪstəsin is the epoch from 18 million to 10000 years BP covering the world's recent period Before Present (BP years are a time scale used in Archaeology, Geology, and other scientific disciplines to specify when events in the past occurred The glaciations that occurred during this glacial period covered many areas of the Northern Hemisphere, and have different names, depending on their geographic distributions: Wisconsin (in North America), Devensian (in the British Isles), Midlandian (in Ireland), Würm (in the Alps), Weichsel (in northern central Europe) and Llanquihue in Chile. Northern Hemisphere is the half of a Planet that is North of the Equator —the word hemisphere literally means 'half ball' The British Isles (Irish variously Na hOileáin Bhriotanacha, Oileáin Iarthair Eorpa, Éire agus an Bhreatain Mhór; Ellanyn Goaldagh Eileanan Ireland (pronounced /ˈaɾlənd/ Éire) is the third largest island in Europe, and the twentieth-largest island in the world The glacial advance reached its maximum extent about 18,000 BP. The Last Glacial Maximum (LGM refers to the time of maximum extent of the Ice sheets during the last Glaciation (the Würm or Wisconsin glaciation) approximately In Europe, the ice sheet reached northern Germany. Germany, officially the Federal Republic of Germany ( ˈbʊndəsʁepuˌbliːk ˈdɔʏtʃlant is a Country in Central Europe.

Next glacial period

See also: Milankovitch cycles

Since orbital variations are predictable,[1] if one has a model that relates orbital variations to climate, it is possible to run such a model forward to "predict" future climate. Milankovitch cycles are the collective effect of changes in the Earth 's movements upon its climate named after Serbian civil engineer and Mathematician Two caveats are necessary: that anthropogenic effects (global warming) are likely to exert a larger influence over the short term; and that the mechanism by which orbital forcing influences climate is not well understood. Anthropogenic effects processes objects or materials are those that are derived from Human activities as opposed to those occurring in Natural environments without Global warming is the increase in the average measured temperature of the Orbital forcing describes the effect on Climate of slow changes in the tilt of the Earth 's axis and shape of the Orbit (see Milankovitch cycles

Work by Berger and Loutre suggests that the current warm climate may last another 50,000 years. [2].

See also

References

  1. ^ F. "Glacial" and "Glaciation" redirect here For the geological periods see Glacial period. The geologic time scale is a chronologic schema (or idealized Model) relating Stratigraphy to time that is used by Geologists and other The glacial history of Minnesota is most defined since the onset of the Last glacial period, which ended some 10000 years ago Milankovitch cycles are the collective effect of changes in the Earth 's movements upon its climate named after Serbian civil engineer and Mathematician Cyclostratigraphy is the study of astronomically forced climate cycles within Sedimentary successions Climate encompasses the temperatures humidity rainfall atmospheric particle count and numerous other meteorogical factors in a given region over long periods of In Astronomy, Precession refers to the movement of the rotational axis of a body such as a planet with respect to Inertial space. The terms greenhouse and icehouse Earth refer to the prevailing global climate on a timescale of millions of years The Snowball Earth Hypothesis as it was originally proposed]] Evidence The Snowball Earth hypothesis was originally devised to explain the apparent presence of An interglacial is a geological interval of warmer global average temperature that separates Glacial periods within an Ice age. A stadial is a period of colder Temperatures during an Interglacial, of insufficient duration or intensity to be considered a Glaciation, or glacial period The Yarkovsky effect is a force acting on a rotating body in space caused by the Anisotropic emission of thermal Photons which carry The Yarkovsky-O'Keefe-Radzievskii-Paddack effect, or YORP effect for short is a second-order variation on the Yarkovsky effect which changes the rotation rate of "Last glacial" redirects here For the period of maximum glacier extent during this time see Last Glacial Maximum The last glacial period The Last Glacial Maximum (LGM refers to the time of maximum extent of the Ice sheets during the last Glaciation (the Würm or Wisconsin glaciation) approximately An ice age is a period of long-term reduction in the Temperature of the Earth 's surface and atmosphere resulting in an expansion of continental Ice sheets Varadi, B. Runnegar, M. Ghil (2003). "Successive Refinements in Long-Term Integrations of Planetary Orbits". The Astrophysical Journal 592: 620–630. doi:10.1086/375560. A digital object identifier ( DOI) is a permanent identifier given to an Electronic document.   doi:10.1086/375560
  2. ^ Berger A, Loutre MF (2002). A digital object identifier ( DOI) is a permanent identifier given to an Electronic document. "Climate: An exceptionally long interglacial ahead?". Science 297 (5585): 1287-1288. doi:10.1126/science.1076120. A digital object identifier ( DOI) is a permanent identifier given to an Electronic document.  
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