The Younger Dryas stadial

Stadial

A stadial is a period of lower temperatures during an interglacial separating the glacial periods of an ice age. Such periods are of insufficient duration or intensity to be considered glacial periods...

, also referred to as the Big Freeze, was a geologically brief (1,300 ± 70 years) period of cold climatic conditions and drought between approximately 12.8 and 11.5 ka BP

Before Present

Before Present years is a time scale used in archaeology, geology, and other scientific disciplines to specify when events in the past occurred. Because the "present" time changes, standard practice is to use AD 1950 as the origin of the age scale, reflecting the fact that radiocarbon...

, or 12,800 and 11,500 years before present. The Younger Dryas stadial

Stadial

A stadial is a period of lower temperatures during an interglacial separating the glacial periods of an ice age. Such periods are of insufficient duration or intensity to be considered glacial periods...

 is thought to have been caused by the collapse of the North American ice sheets, although rival theories have been proposed.

The period followed the Bølling

Bølling Oscillation

The Bølling oscillation was a warm interstadial period between the Oldest Dryas and Older Dryas stadials, at the end of the last glacial period. It is named after a peat sequence discovered at Bølling lake, central Jutland...

-Allerød

Allerød Oscillation

The Allerød period was a warm and moist global interstadial that occurred at the end of the last glacial period. The Allerød oscillation raised temperatures , before they declined again in the succeeding Younger Dryas period, which was followed by the present interglacial period.In some regions,...

 interstadial at the end of the Pleistocene

Pleistocene

The Pleistocene is the epoch from 2,588,000 to 11,700 years BP that spans the world's recent period of repeated glaciations. The name pleistocene is derived from the Greek and ....

  and preceded the Preboreal

Boreal (period)

In paleoclimatology of the Holocene, the Boreal was the first of the Blytt-Sernander sequence of north European climatic phases that were originally based on the study of Danish peat bogs, named for Axel Blytt and Rutger Sernander, who first established the sequence. In peat bog sediments, the...

 of the early Holocene

Holocene

The Holocene is a geological epoch which began at the end of the Pleistocene and continues to the present. The Holocene is part of the Quaternary period. Its name comes from the Greek words and , meaning "entirely recent"...

.