Stadials and interstadials are phases dividing the Quaternary period, or the last 2.6 million years. Stadials are periods of colder climate while interstadials are periods of warmer climate. Each Quaternary climate phase is associated with a Marine Isotope Stage (MIS) number, which describe alternation between warmer and cooler temperatures as measured by oxygen isotope data. Stadials have even MIS numbers and interstadials odd MIS numbers. The current

Holocene The Holocene ( ) is the current geological epoch. It began approximately 11,650 cal years Before Present (), after the Last Glacial Period, which concluded with the Holocene glacial retreat. The Holocene and the preceding Pleistocene togeth ...

interstadial is MIS 1 and the

Last glacial maximum The Last Glacial Maximum (LGM), also referred to as the Late Glacial Maximum, was the most recent time during the Last Glacial Period that ice sheets were at their greatest extent. Ice sheets covered much of Northern North America, Northern Eu ...

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, while

interglacial An interglacial period (or alternatively interglacial, interglaciation) 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 ...

s last for more than ten thousand and glacials for about one hundred thousand. In order 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 will only reach the stage of boreal vegetation. While the MIS 1 interstadial encompasses the entirety of the present Holocene interglacial, the

Wisconsin glaciation The Wisconsin Glacial Episode, also called the Wisconsin glaciation, was the most recent glacial period of the North American ice sheet complex. This advance included the Cordilleran Ice Sheet, which nucleated in the northern North American Cor ...

encompasses MIS 2, 3, and 4. Glacials and Interglacials refer to the 100kyr cycles associated with Milankovitch cycles, while 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 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 are three stadials that occurred during the warming since the

Last Glacial Maximum The Last Glacial Maximum (LGM), also referred to as the Late Glacial Maximum, was the most recent time during the Last Glacial Period that ice sheets were at their greatest extent. Ice sheets covered much of Northern North America, Northern Eu ...

. 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 ( kl, Kalaallit Nunaat, ; da, Grønland, ) is an island country in North America that is part of the Kingdom of Denmark. It is located between the Arctic and Atlantic oceans, east of the Canadian Arctic Archipelago. Greenland is ...

ice core An ice core is a core sample that is typically removed from an ice sheet or a high mountain glacier. Since the ice forms from the incremental buildup of annual layers of snow, lower layers are older than upper ones, and an ice core contains ...

s show 24 interstadials during the one hundred thousand years of the Wisconsin glaciation. 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.

References