Stadials and interstadials are phases dividing the

Quaternary The Quaternary ( ) is the current and most recent of the three periods of the Cenozoic Era in the geologic time scale of the International Commission on Stratigraphy (ICS), as well as the current and most recent of the twelve periods of the ...

period, or the last 2.6 million years. Stadials are periods of colder climate, and interstadials are periods of warmer climate. Each Quaternary climate phase has been assigned 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 The Holocene () is the current geologic time scale, geological epoch, beginning approximately 11,700 years ago. It follows the Last Glacial Period, which concluded with the Holocene glacial retreat. The Holocene and the preceding Pleistocene to ...

interstadial is MIS 1, and the

Last Glacial Maximum The Last Glacial Maximum (LGM), also referred to as the Last Glacial Coldest Period, was the most recent time during the Last Glacial Period where ice sheets were at their greatest extent between 26,000 and 20,000 years ago. Ice sheets covered m ...

stadial is MIS 2. Marine isotope stages are sometimes subdivided into stadials and interstadials by minor climate fluctuations within the overall stadial or interstadial, 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. The MIS 1 interstadial encompasses the entirety of the present Holocene interglacial, but the

Wisconsin glaciation The Wisconsin glaciation, also called the Wisconsin glacial episode, was the most recent glacial period of the North American ice sheet complex, peaking more than 20,000 years ago. This advance included the Cordilleran Ice Sheet, which nucleated ...

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 Allerød may refer to: * Allerød Municipality, a municipality in Denmark ** Lillerød, also called ''Allerød'', seat of the municipality ** Allerød station, a railway station in the Danish town * Allerød oscillation, a climatic period at the en ...

, where they are not clearly distinguished in the

stratigraphy Stratigraphy is a branch of geology concerned with the study of rock layers (strata) and layering (stratification). It is primarily used in the study of sedimentary and layered volcanic rocks. Stratigraphy has three related subfields: lithost ...

, are taken together to form the Bølling–Allerød Interstadial, and dated from about 14,700 to 12,700 years before the present.

Dryas periods

The Oldest, Older, and

Younger Dryas The Younger Dryas (YD, Greenland Stadial GS-1) was a period in Earth's geologic history that occurred circa 12,900 to 11,700 years Before Present (BP). It is primarily known for the sudden or "abrupt" cooling in the Northern Hemisphere, when the ...

are three stadials that occurred during the warming since the

. 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 Greenland is an autonomous territory in the Danish Realm, Kingdom of Denmark. It is by far the largest geographically of three constituent parts of the kingdom; the other two are metropolitan Denmark and the Faroe Islands. Citizens of Greenlan ...

ice cores show 24 interstadials during the 100,000 years of the

. Referred to as the Dansgaard–Oeschger event, 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.

References