Interglacial

Interglacial image

Shows the pattern of temperature and ice volume changes associated with recent glacials and interglacials

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 interglacial began at the end of the Pleistocene, about 11,700 years ago.

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Pleistocene

During the 2.5 million years of the Pleistocene, numerous glacials, or significant advances of continental ice sheets, in North America and Europe, occurred at intervals of approximately 40,000 to 100,000 years. The long glacial periods were separated by more temperate and shorter interglacials.

During interglacials, such as the present one, the climate warms and the tundra recedes polewards following the ice sheets. Forests return to areas that once supported tundra vegetation. Interglacials are identified on land or in shallow epicontinental seas by their paleontology. Floral and faunal remains of species pointing to temperate climate and indicating a specific age are used to identify particular interglacials. Commonly used are mammalian and molluscan species, pollen and plant macro-remains (seeds and fruits). However, many other fossil remains may be helpful: insects, ostracods, foraminifera, diatoms, etc. Recently, ice cores and ocean sediment cores provide more quantitative and accurately-dated evidence for temperatures and total ice volumes.

Interglacials and glacials coincide with cyclic changes in the Earth's orbit. Three orbital variations contribute to interglacials. The first is a change in the Earth's orbit around the sun, or eccentricity. The second is a shift in the tilt of the Earth's axis, or obliquity. The third is the wobbling motion of Earth's axis, or precession.

In the Southern Hemisphere, warmer summers occur when the lower-half of the Earth is tilted toward the sun and the planet is nearest the sun in its elliptical orbit. Cooler summers occur when the Earth is farthest from the sun during the Southern Hemisphere summer. Such effects are more pronounced when the eccentricity of the orbit is large. When the obliquity is large, seasonal changes are more extreme.

Interglacials are a useful tool for geological mapping and for anthropologists, as they can be used as a dating method for hominid fossils.

Brief periods of milder climate that occurred during the last glacial are called interstadials. Most, but not all, interstadials are shorter than interglacials. Interstadial climates may have been relatively warm, but not neces... ...read more

Eemian
3 months ago

Eemian ... called the last interglacial, Sangamonian Stage, Ipswichian, Mikulin, Kaydaky, penultimate, Valdivia or Riss-Würm) was the interglacial period which began...

Ice age
1 day ago

Ice age ... ice ages), and intermittent warm periods within an ice age are called interglacials or interstadials. In glaciology, ice age implies the presence of extensive...

Glacial period
3 months ago

Glacial period ... ice age that is marked by colder temperatures and glacier advances. Interglacials, on the other hand, are periods of warmer climate between glacial periods...

Quaternary glaciation
2 months ago

Quaternary glaciation ... the Pleistocene glaciation, is an alternating series of glacial and interglacial periods during the Quaternary period that began 2.58 Ma (million years...

Timeline of glaciation
3 months ago

Timeline of glaciation ... referred to as glacial periods and interglacial periods, respectively. The Earth is currently in such an interglacial period of the Quaternary glaciation...

Waalian interglacial
2 months ago

Waalian interglacial ... The Waalian interglacial (German: Waal-Warmzeit or Waal-Interglazial) (Zagwijn, 1960) was an interglacial period in northern Europe that lasted from about...

Flandrian interglacial
2 months ago

Flandrian interglacial ... The Flandrian interglacial or stage is the name given by geologists and archaeologists in the British Isles to the first, and so far only, stage of the...

Holstein interglacial
2 months ago

Holstein interglacial ... The Holstein interglacial (German: Holstein-Warmzeit or Holstein-Interglazial), also called the Mindel-Riss interglacial (Mindel-Riß-Interglazial) in...

Chibanian
2 months ago

Chibanian ... field last underwent reversal. It ends with the onset of the Eemian interglacial period (Marine Isotope Stage 5). The term Middle Pleistocene was in use...

Pleistocene
3 months ago

Pleistocene ... an epoch, the Holocene is not significantly different from previous interglacial intervals within the Pleistocene. In the ICS timescale, the Pleistocene...

Last Glacial Period
2 months ago
Wisconsin glaciation
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Greenhouse and icehouse Earth
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Netherlands
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Marine isotope stages
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Late Cenozoic Ice Age
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Hoxnian Stage
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Marine Isotope Stage 5
2 months ago
Marine Isotope Stage 9
2 months ago
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