Stadial

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Stadials and interstadials are phases dividing the Quaternary period, or the last 2.6 million years. Stadials are periods of colder climate, and interstadials are periods of warmer climate.

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Each Quaternary climate phase is associated with a Marine Isotope Stage (MIS) number, which describes the alternation between warmer and cooler temperatures, as measured by oxygen isotope data. Stadials have even MIS numbers, and interstadials have odd MIS numbers. The current Holocene interstadial is MIS 1, and the Last Glacial Maximum stadial is MIS 2.

Marine Isotope Stages are sometimes further subdivided into stadials and interstadials by minor climate fluctuations within the overall stadial or interstadial regime, which are indicated by letters. The odd-numbered interstadial MIS 5, also known as the Sangamonian interglacial, contains two periods of relative cooling, and so is subdivided into three interstadials (5a, 5c, 5e) and two stadials (5b, 5d). A stadial isotope stage like MIS 6 would be subdivided by periods of relative warming, and so in that case the first and last subdivisions would be stadials; MIS 6a, 6c and 6e are stadials while 6b and 6d are interstadials.

Distinction between stadials and glacials

Generally, stadials endure for a thousand years or less and interstadials for less than ten thousand years, and interglacials last for more than ten thousand and glacials for about one hundred thousand. For a period to be considered an interglacial, it changes from Arctic through sub-Arctic to boreal to temperate conditions and back again. An interstadial reaches only the stage of boreal vegetation. [1]

The MIS 1 interstadial encompasses the entirety of the present Holocene interglacial, but the Wisconsin glaciation encompasses MIS 2, 3, and 4.

Glacials and interglacials refer to the 100,000-year cycles associated with Milankovitch cycles, and stadials and interstadials are defined by the actual oxygen-isotope temperature record.

List of stadials and interstadials

Bølling/Allerød interstadial

The Bølling oscillation and the Allerød oscillation, where they are not clearly distinguished in the stratigraphy, are taken together to form the Bølling/Allerød interstadial, and dated from about 14,700 to 12,700 years before the present. [2]

Dryas Periods

The Oldest, Older, and Younger Dryas are three stadials that occurred during the warming since the Last Glacial Maximum. The Older Dryas occurred between the Bølling and Allerød interstadials. All three periods are named for the arctic plant species, Dryas octopetala, which proliferated during these cold periods.

Dansgaard-Oeschger events

Greenland ice cores show 24 interstadials during the 100,000 years of the Wisconsin glaciation. [3] Referred to as the Dansgaard-Oeschger events, they have been extensively studied, and in their northern European contexts are sometimes named after towns, such as the Brorup, the Odderade, the Oerel, the Glinde, the Hengelo, or the Denekamp.

See also

Related Research Articles

<span class="mw-page-title-main">Pleistocene</span> First epoch of the Quaternary Period

The Pleistocene is the geological epoch that lasted from c. 2.58 million to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was finally confirmed in 2009 by the International Union of Geological Sciences, the cutoff of the Pleistocene and the preceding Pliocene was regarded as being 1.806 million years Before Present (BP). Publications from earlier years may use either definition of the period. The end of the Pleistocene corresponds with the end of the last glacial period and also with the end of the Paleolithic age used in archaeology. The name is a combination of Ancient Greek πλεῖστος (pleîstos), meaning "most", and καινός, meaning "new".

The Younger Dryas, which occurred circa 12,900 to 11,700 years BP, was a return to glacial conditions which temporarily reversed the gradual climatic warming after the Last Glacial Maximum, which lasted from circa 27,000 to 20,000 years BP. The Younger Dryas was the last stage of the Pleistocene epoch that spanned from 2,580,000 to 11,700 years BP and it preceded the current, warmer Holocene epoch. The Younger Dryas was the most severe and longest lasting of several interruptions to the warming of the Earth's climate, and it was preceded by the Late Glacial Interstadial, an interval of relative warmth that lasted from 14,670 to 12,900 BP.

<span class="mw-page-title-main">Last Glacial Period</span> Period of major glaciations of the Northern Hemisphere (115,000–12,000 years ago)

The Last Glacial Period (LGP), also known colloquially as the Last Ice Age or simply Ice Age, occurred from the end of the Last Interglacial to the end of the Younger Dryas, encompassing the period c. 115,000 – c. 11,700 years ago.

The Allerød oscillation was a warm and moist global interstadial that occurred c.13,900 to 12,900 BP. It was preceded by the Older Dryas and followed by the Younger Dryas cold periods. The Allerød was nearly at the end of the Last Glacial Period. It raised temperatures in the northern Atlantic region to almost present-day levels, before they declined again in the Younger Dryas, which was followed by the present warm Holocene.

<span class="mw-page-title-main">Timeline of glaciation</span> Chronology of the major ice ages of the Earth

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.

<span class="mw-page-title-main">Würm glaciation</span> Last glacial period in the Alpine region

The Würm glaciation or Würm stage, usually referred to in the literature as the Würm, was the last glacial period in the Alpine region. It is the youngest of the major glaciations of the region that extended beyond the Alps themselves. Like most of the other ice ages of the Pleistocene epoch, it is named after a river, in this case the Würm in Bavaria, a tributary of the Amper.

The Bølling oscillation, also Bølling interstadial, was a cool temperate climatic interstadial between the glacial Oldest Dryas and Older Dryas stadials, between 14,700 and 14,100 BP, near to the end of the last glacial period. It is named after a peat sequence discovered at Bølling lake in central Jutland, Denmark. It is used to describe a period of time in relation to Pollen zone Ib—in regions where the Older Dryas is not detected in climatological evidence, the Bølling–Allerød is considered a single interstadial period.

The Flandrian interglacial or stage is the regional name given by geologists and archaeologists in the British Isles to the period from around 12,000 years ago, at the end of the last glacial period, to the present day. As such, it is in practice identical in span to the Holocene.

<span class="mw-page-title-main">Marine isotope stages</span> Alternating warm and cool periods in the Earths paleoclimate, deduced from oxygen isotope data

Marine isotope stages (MIS), marine oxygen-isotope stages, or oxygen isotope stages (OIS), are alternating warm and cool periods in the Earth's paleoclimate, deduced from oxygen isotope data derived from deep sea core samples. Working backwards from the present, which is MIS 1 in the scale, stages with even numbers have high levels of oxygen-18 and represent cold glacial periods, while the odd-numbered stages are lows in the oxygen-18 figures, representing warm interglacial intervals. The data are derived from pollen and foraminifera (plankton) remains in drilled marine sediment cores, sapropels, and other data that reflect historic climate; these are called proxies.

<span class="mw-page-title-main">Ahrensburg culture</span> Late Upper Paleolithic nomadic hunter culture

The Ahrensburg culture or Ahrensburgian was a late Upper Paleolithic nomadic hunter culture in north-central Europe during the Younger Dryas, the last spell of cold at the end of the Weichsel glaciation resulting in deforestation and the formation of a tundra with bushy arctic white birch and rowan. The most important prey was the wild reindeer. The earliest definite finds of arrow and bow date to this culture, though these weapons might have been invented earlier. The Ahrensburgian was preceded by the Hamburg and Federmesser cultures and superseded by the Maglemosian and Swiderian cultures. Ahrensburgian finds were made in southern and western Scandinavia, the North German plain and western Poland. The Ahrensburgian area also included vast stretches of land now at the bottom of the North and Baltic Sea, since during the Younger Dryas the coastline took a much more northern course than today.

<span class="mw-page-title-main">Interglacial</span> Geological interval of warmer temperature that separates glacial periods within an ice age

An interglacial period is a geological interval of warmer global average temperature lasting thousands of years that separates consecutive glacial periods within an ice age. The current Holocene interglacial began at the end of the Pleistocene, about 11,700 years ago.

<span class="mw-page-title-main">Late Pleistocene</span> Third division (unofficial) of the Pleistocene Epoch

The Late Pleistocene is an unofficial age in the international geologic timescale in chronostratigraphy, also known as the upper Pleistocene from a stratigraphic perspective. It is intended to be the fourth division of the Pleistocene Epoch within the ongoing Quaternary Period. It is currently defined as the time between c. 129,000 and c. 11,700 years ago. The late Pleistocene equates to the proposed Tarantian Age of the geologic time scale, preceded by the officially ratified Chibanian. The beginning of the Late Pleistocene is the transition between the end of the Penultimate Glacial Period and the beginning of the Last Interglacial around 130,000 years ago. The Late Pleistocene ends with the termination of the Younger Dryas, some 11,700 years ago when the Holocene Epoch began.

The Older Dryas was a stadial (cold) period between the Bølling and Allerød interstadials, about 14,000 years Before Present, towards the end of the Pleistocene. Its date range is not well defined, with estimates varying by 400 years, but its duration is agreed to have been around two centuries.

<span class="mw-page-title-main">Oldest Dryas</span> Abrupt climatic cooling event during the last glacial retreat

The Oldest Dryas is a biostratigraphic subdivision layer corresponding to a relatively abrupt climatic cooling event, or stadial, which occurred during the last glacial retreat. The time period to which the layer corresponds is poorly defined and varies between regions, but it is generally dated as starting at 18.5–17 thousand years (ka) before present (BP) and ending 15–14 ka BP. As with the Younger and Older Dryas events, the stratigraphic layer is marked by abundance of the pollen and other remains of Dryas octopetala, an indicator species that colonizes arctic-alpine regions. The termination of the Oldest Dryas is marked by an abrupt oxygen isotope excursion, which has been observed at many sites in the Alps that correspond to this interval of time.

The Bølling–Allerød interstadial, also called the Late Glacial Interstadial, was an abrupt warm and moist interstadial period that occurred during the final stages of the Last Glacial Period. This warm period ran from 14,690 to 12,890 years before the present (BP). It began with the end of the cold period known as the Oldest Dryas, and ended abruptly with the onset of the Younger Dryas, a cold period that reduced temperatures back to near-glacial levels within a decade.

<span class="mw-page-title-main">Quaternary glaciation</span> Series of alternating glacial and interglacial periods

The Quaternary glaciation, also known as the Pleistocene glaciation, is an alternating series of glacial and interglacial periods during the Quaternary period that began 2.58 Ma and is ongoing. Although geologists describe this entire period up to the present as an "ice age", in popular culture this term usually refers to the most recent glacial period, or to the Pleistocene epoch in general. Since Earth still has polar ice sheets, geologists consider the Quaternary glaciation to be ongoing, though currently in an interglacial period.

<span class="mw-page-title-main">Weichselian glaciation</span> Last glacial period and its associated glaciation in northern parts of Europe

The Weichselian glaciation was the last glacial period and its associated glaciation in northern parts of Europe. In the Alpine region it corresponds to the Würm glaciation. It was characterized by a large ice sheet that spread out from the Scandinavian Mountains and extended as far as the east coast of Schleswig-Holstein, northern Poland and Northwest Russia. This glaciation is also known as the Weichselian ice age, Vistulian glaciation, Weichsel or, less commonly, the Weichsel glaciation, Weichselian cold period (Weichsel-Kaltzeit), Weichselian glacial (Weichsel-Glazial), Weichselian Stage or, rarely, the Weichselian complex (Weichsel-Komplex).

<span class="mw-page-title-main">Marine Isotope Stage 5</span> Marine isotope stage in the geologic temperature record, between 130,000 and 80,000 years ago

Marine Isotope Stage 5 or MIS 5 is a marine isotope stage in the geologic temperature record, between 130,000 and 80,000 years ago. Sub-stage MIS 5e corresponds to the Last Interglacial, also called the Eemian or Sangamonian, the last major interglacial period before the Holocene, which extends to the present day. Interglacial periods which occurred during the Pleistocene are investigated to better understand present and future climate variability. Thus, the present interglacial, the Holocene, is compared with MIS 5 or the interglacials of Marine Isotope Stage 11.

<span class="mw-page-title-main">Marine Isotope Stage 9</span>

Marine Isotope Stage 9 was an interglacial period that consisted of two interstadial and one stadial period. It is the final period of the Lower Paleolithic and lasted from 337,000 to 300,000 years ago according to Lisiecki and Raymo's LR04 Benthic Stack. It corresponds to the Purfleet Interglacial in Britain, the Holstein Interglacial in continental Europe, and the Pre-Illinoian in North America.

<span class="mw-page-title-main">Late Cenozoic Ice Age</span> Ice age of the last 34 million years, in particular in Antarctica

The Late Cenozoic Ice Age, or Antarctic Glaciation, began 34 million years ago at the Eocene-Oligocene Boundary and is ongoing. It is Earth's current ice age or icehouse period. Its beginning is marked by the formation of the Antarctic ice sheets.

References

  1. Cox, Barry C.; Moore, Peter D.; Ladle, Richard (31 May 2016). "Ice and Change". Biogeography: an Ecological and Evolutionary Approach (9 ed.). John Wiley & Sons Ltd. p. 356. ISBN   9781118968581. The sequence of events demonstrated in the fossil material of such an interglacial shows a progressive change from high arctic conditions (virtually no life) through subarctic (tundra vegetation) to boreal (birch and pine forest) to temperate (deciduous forest) and then back through boreal to arctic conditions once more. If the warm event is only of a short duration, or the temperatures are not sufficiently high, then the vegetation changes may only reach a boreal stage of development. In this case, it's termed an interstadial.
  2. Cronin, Thomas M. (1999). Principles of Climatology. New York: Columbia University Press. p. 204.
  3. Wilson, R. C. L.; Drury, S. A.; Chapman, J. L. (2000). The Great Ice Age: Climate Change and Life. London: Routledge. p. 125. ISBN   0-415-19841-0.