Holocene

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This article is about the geological epoch. Holocene_sentence_0

For dating the Holocene Era, see Holocene calendar. Holocene_sentence_1

For the Bon Iver song, see Holocene (song). Holocene_sentence_2

For the music venue in Portland, Oregon, see Holocene (Portland, Oregon). Holocene_sentence_3

Holocene_table_infobox_0

HoloceneHolocene_header_cell_0_0_0
ChronologyHolocene_header_cell_0_1_0
EtymologyHolocene_header_cell_0_2_0
Name formalityHolocene_header_cell_0_3_0 FormalHolocene_cell_0_3_1
Usage InformationHolocene_header_cell_0_4_0
Celestial bodyHolocene_header_cell_0_5_0 EarthHolocene_cell_0_5_1
UsageHolocene_header_cell_0_6_0 Global (ICS)Holocene_cell_0_6_1
Time scale(s) usedHolocene_header_cell_0_7_0 ICS Time ScaleHolocene_cell_0_7_1
DefinitionHolocene_header_cell_0_8_0
Chronological unitHolocene_header_cell_0_9_0 EpochHolocene_cell_0_9_1
Stratigraphic unitHolocene_header_cell_0_10_0 SeriesHolocene_cell_0_10_1
Time span formalityHolocene_header_cell_0_11_0 FormalHolocene_cell_0_11_1
Lower boundary definitionHolocene_header_cell_0_12_0 End of the Younger Dryas stadial.Holocene_cell_0_12_1
Lower boundary GSSPHolocene_header_cell_0_13_0 NGRIP2 ice core, GreenlandHolocene_cell_0_13_1
GSSP ratifiedHolocene_header_cell_0_14_0 2008 (as base of Holocene)Holocene_cell_0_14_1
Upper boundary definitionHolocene_header_cell_0_15_0 Present dayHolocene_cell_0_15_1
Upper boundary GSSPHolocene_header_cell_0_16_0 N/A

N/AHolocene_cell_0_16_1

GSSP ratifiedHolocene_header_cell_0_17_0 N/AHolocene_cell_0_17_1

The Holocene ( /ˈhɒl.əˌsiːn, ˈhɒl.oʊ-, ˈhoʊ.lə-, ˈhoʊ.loʊ-/ HOL-ə-seen, HOL-oh-, HOH-lə-, HOH-loh-) is the current geological epoch. Holocene_sentence_4

It began approximately 11,650 cal years before present, after the last glacial period, which concluded with the Holocene glacial retreat. Holocene_sentence_5

The Holocene and the preceding Pleistocene together form the Quaternary period. Holocene_sentence_6

The Holocene has been identified with the current warm period, known as MIS 1. Holocene_sentence_7

It is considered by some to be an interglacial period within the Pleistocene Epoch, called the Flandrian interglacial. Holocene_sentence_8

The Holocene corresponds with rapid proliferation, growth and impacts of the human species worldwide, including all of its written history, technological revolutions, development of major civilizations, and overall significant transition towards urban living in the present. Holocene_sentence_9

The human impact on modern-era Earth and its ecosystems may be considered of global significance for the future evolution of living species, including approximately synchronous lithospheric evidence, or more recently hydrospheric and atmospheric evidence of the human impact. Holocene_sentence_10

In July 2018, the International Union of Geological Sciences split the Holocene epoch into three distinct subsections, Greenlandian (11,700 years ago to 8,200 years ago), Northgrippian (8,200 years ago to 4,200 years ago) and Meghalayan (4,200 years ago to the present), as proposed by International Commission on Stratigraphy. Holocene_sentence_11

The boundary stratotype of the Meghalayan is a speleothem in Mawmluh cave in India, and the global auxiliary stratotype is an ice core from Mount Logan in Canada. Holocene_sentence_12

Etymology Holocene_section_0

The word is formed from two Ancient Greek words. Holocene_sentence_13

Holos (ὅλος) is the Greek word for "whole." Holocene_sentence_14

"Cene" comes from the Greek word kainos (καινός), meaning "new." Holocene_sentence_15

The concept is that this epoch is "entirely new." Holocene_sentence_16

The suffix '-cene' is used for all the seven epochs of the Cenozoic Era. Holocene_sentence_17

Overview Holocene_section_1

It is accepted by the International Commission on Stratigraphy that the Holocene started approximately 11,650 cal years BP. Holocene_sentence_18

The Subcommission on Quaternary Stratigraphy deprecates the term 'Recent' as an alternative to Holocene; it also observes that the term Flandrian, derived from marine transgression sediments on the Flanders coast of Belgium, has been used as a synonym for Holocene by authors who consider the last 10,000 years should have the same stage-status as previous interglacial events and thus be included in the Pleistocene. Holocene_sentence_19

The International Commission on Stratigraphy, however, considers the Holocene an epoch following the Pleistocene and specifically the last glacial period. Holocene_sentence_20

Local names for the last glacial period include the Wisconsinan in North America, the Weichselian in Europe, the Devensian in Britain, the Llanquihue in Chile and the Otiran in New Zealand. Holocene_sentence_21

The Holocene can be subdivided into five time intervals, or chronozones, based on climatic fluctuations: Holocene_sentence_22

Holocene_unordered_list_0

  • Preboreal (10 ka–9 ka BP),Holocene_item_0_0
  • Boreal (9 ka–8 ka BP),Holocene_item_0_1
  • Atlantic (8 ka–5 ka BP),Holocene_item_0_2
  • Subboreal (5 ka–2.5 ka BP) andHolocene_item_0_3
  • Subatlantic (2.5 ka BP–present).Holocene_item_0_4

Holocene_description_list_1

Geologists working in different regions are studying sea levels, peat bogs and ice core samples by a variety of methods, with a view toward further verifying and refining the Blytt–Sernander sequence. Holocene_sentence_23

This is a classification of climatic periods initially defined by plant remains in peat mosses. Holocene_sentence_24

Though the method was once thought to be of little interest, based on C dating of peats that was inconsistent with the claimed chronozones, investigators have found a general correspondence across Eurasia and North America. Holocene_sentence_25

The scheme was defined for Northern Europe, but the climate changes were claimed to occur more widely. Holocene_sentence_26

The periods of the scheme include a few of the final pre-Holocene oscillations of the last glacial period and then classify climates of more recent prehistory. Holocene_sentence_27

Paleontologists have not defined any faunal stages for the Holocene. Holocene_sentence_28

If subdivision is necessary, periods of human technological development, such as the Mesolithic, Neolithic, and Bronze Age, are usually used. Holocene_sentence_29

However, the time periods referenced by these terms vary with the emergence of those technologies in different parts of the world. Holocene_sentence_30

Climatically, the Holocene may be divided evenly into the Hypsithermal, with warmer temperatures on average in many regions, and Neoglacial periods. Holocene_sentence_31

The boundary coincides with the start of the Bronze Age in Europe. Holocene_sentence_32

According to some scholars, a third division, the Anthropocene, has now begun. Holocene_sentence_33

This term is used to denote the present time interval in which many geologically significant conditions and processes have been profoundly altered by human activities. Holocene_sentence_34

The ‘Anthropocene’ (a term coined by Paul Crutzen and Eugene Stoermer in 2000) is not a formally defined geological unit. Holocene_sentence_35

The Subcommission on Quaternary Stratigraphy of the International Commission on Stratigraphy has a working group to determine whether it should be. Holocene_sentence_36

In May 2019, members of the working group voted in favour of recognizing the Anthropocene as formal chrono-stratigraphic unit, with stratigraphic signals around the mid-twentieth century C.E. as its base. Holocene_sentence_37

The exact criteria have still to be decided upon, after which the recommendation also has to be approved by the working group’s parent bodies (ultimately the International Union of Geological Sciences). Holocene_sentence_38

Geology Holocene_section_2

Continental motions due to plate tectonics are less than a kilometre over a span of only 10,000 years. Holocene_sentence_39

However, ice melt caused world sea levels to rise about 35 m (115 ft) in the early part of the Holocene. Holocene_sentence_40

In addition, many areas above about 40 degrees north latitude had been depressed by the weight of the Pleistocene glaciers and rose as much as 180 m (590 ft) due to post-glacial rebound over the late Pleistocene and Holocene, and are still rising today. Holocene_sentence_41

The sea level rise and temporary land depression allowed temporary marine incursions into areas that are now far from the sea. Holocene_sentence_42

Holocene marine fossils are known, for example, from Vermont and Michigan. Holocene_sentence_43

Other than higher-latitude temporary marine incursions associated with glacial depression, Holocene fossils are found primarily in lakebed, floodplain, and cave deposits. Holocene_sentence_44

Holocene marine deposits along low-latitude coastlines are rare because the rise in sea levels during the period exceeds any likely tectonic uplift of non-glacial origin. Holocene_sentence_45

Post-glacial rebound in the Scandinavia region resulted in the formation of the Baltic Sea. Holocene_sentence_46

Earthquakes are a leading cause of sediment deformation, leading to the creation and destruction of bodies of water. Holocene_sentence_47

The region continues to rise, still causing weak earthquakes across Northern Europe. Holocene_sentence_48

The equivalent event in North America was the rebound of Hudson Bay, as it shrank from its larger, immediate post-glacial Tyrrell Sea phase, to near its present boundaries. Holocene_sentence_49

Climate Holocene_section_3

Climate has been fairly stable over the Holocene. Holocene_sentence_50

Ice core records show that before the Holocene there was global warming after the end of the last ice age and cooling periods, but climate changes became more regional at the start of the Younger Dryas. Holocene_sentence_51

During the transition from the last glacial to the Holocene, the Huelmo–Mascardi Cold Reversal in the Southern Hemisphere began before the Younger Dryas, and the maximum warmth flowed south to north from 11,000 to 7,000 years ago. Holocene_sentence_52

It appears that this was influenced by the residual glacial ice remaining in the Northern Hemisphere until the later date. Holocene_sentence_53

The Holocene climatic optimum (HCO) was a period of warming in which the global climate became warmer. Holocene_sentence_54

However, the warming was probably not uniform across the world. Holocene_sentence_55

This period of warmth ended about 5,500 years ago with the descent into the Neoglacial and concomitant Neopluvial. Holocene_sentence_56

At that time, the climate was not unlike today's, but there was a slightly warmer period from the 10th–14th centuries known as the Medieval Warm Period. Holocene_sentence_57

This was followed by the Little Ice Age, from the 13th or 14th century to the mid-19th century. Holocene_sentence_58

The temporal and spatial extent of Holocene climate change is an area of considerable uncertainty, with radiative forcing recently proposed to be the origin of cycles identified in the North Atlantic region. Holocene_sentence_59

Climate cyclicity through the Holocene (Bond events) has been observed in or near marine settings and is strongly controlled by glacial input to the North Atlantic. Holocene_sentence_60

Periodicities of ≈2500, ≈1500, and ≈1000 years are generally observed in the North Atlantic. Holocene_sentence_61

At the same time spectral analyses of the continental record, which is remote from oceanic influence, reveal persistent periodicities of 1,000 and 500 years that may correspond to solar activity variations during the Holocene epoch. Holocene_sentence_62

A 1,500-year cycle corresponding to the North Atlantic oceanic circulation may have had widespread global distribution in the Late Holocene. Holocene_sentence_63

Ecological developments Holocene_section_4

Animal and plant life have not evolved much during the relatively short Holocene, but there have been major shifts in the distributions of plants and animals. Holocene_sentence_64

A number of large animals including mammoths and mastodons, saber-toothed cats like Smilodon and Homotherium, and giant sloths disappeared in the late Pleistocene and early Holocene—especially in North America, where animals that survived elsewhere (including horses and camels) became extinct. Holocene_sentence_65

This extinction of American megafauna has been blamed by some on the Clovis people, who vanished at the same time, though climatic change or a bolide impact are favored by others. Holocene_sentence_66

Throughout the world, ecosystems in cooler climates that were previously regional have been isolated in higher altitude ecological "islands". Holocene_sentence_67

The 8.2 ka event, an abrupt cold spell recorded as a negative excursion in the δO record lasting 400 years, is the most prominent climatic event occurring in the Holocene epoch, and may have marked a resurgence of ice cover. Holocene_sentence_68

It has been suggested that this event was caused by the final drainage of Lake Agassiz, which had been confined by the glaciers, disrupting the thermohaline circulation of the Atlantic. Holocene_sentence_69

Subsequent research, however, suggested that the discharge was probably superimposed upon a longer episode of cooler climate lasting up to 600 years and observed that the extent of the area affected was unclear. Holocene_sentence_70

Human developments Holocene_section_5

Further information: Timeline of human prehistory, History of the world, Human history, and Anthropocene Holocene_sentence_71

The beginning of the Holocene corresponds with the beginning of the Mesolithic age in most of Europe, but in regions such as the Middle East and Anatolia with a very early neolithisation, Epipaleolithic is preferred in place of Mesolithic. Holocene_sentence_72

Cultures in this period include Hamburgian, Federmesser, and the Natufian culture, during which the oldest inhabited places still existing on Earth were first settled, such as Tell es-Sultan (Jericho) in the Middle East. Holocene_sentence_73

There is also evolving archeological evidence of proto-religion at locations such as Göbekli Tepe, as long ago as the 9th millennium BCE. Holocene_sentence_74

Both are followed by the aceramic Neolithic (Pre-Pottery Neolithic A and Pre-Pottery Neolithic B) and the pottery Neolithic. Holocene_sentence_75

The Late Holocene brought advancements such as the bow and arrow and saw new methods of warfare in North America. Holocene_sentence_76

Spear throwers and their large points were replaced by the bow and arrow with its small narrow points beginning in Oregon and Washington. Holocene_sentence_77

Villages built on defensive bluffs indicate increased warfare, leading to food gathering in communal groups for protection rather than individual hunting. Holocene_sentence_78

See also Holocene_section_6

Credits to the contents of this page go to the authors of the corresponding Wikipedia page: en.wikipedia.org/wiki/Holocene.