Holocene
Encyclopedia
The Holocene is a geological
epoch
which began at the end of the Pleistocene (around 10,000 14C years
ago) and continues to the present. The Holocene is part of the Quaternary
period. Its name comes from the Greek
words (holos, whole or entire) and (kainos, new), meaning "entirely recent". It has been identified with the current warm period, known as MIS 1
and based on that past evidence, can be considered an interglacial
in the current ice age
.
The Holocene also encompasses within it the growth and impacts of the human species world-wide, including all its written history and overall significant transition toward urban living in the present. Given these, a new synonym Anthropocene
, is specifically proposed and used for the time period since approximately synchronous lithospheric evidence, or more recently atmospheric evidence, of human impacts have been found on the Earth
and its ecosystem
s; these impacts may be considered of global significance for future evolution of living species.
, i.e., around 10,000 BC. The period follows the last glacial period (regionally known as the Wisconsinan Glacial Period, the Baltic-Scandinavian Ice Age, or the Weichsel glacial). The Holocene can be subdivided into five time intervals, or chronozone
s, based on climatic fluctuations:
The Blytt-Sernander
classification of climatic periods defined, initially, by plant remains in peat mosses, is now of purely historical interest. The scheme was defined for north Europe, but the climate change
s were claimed to occur more widely. 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
.
Paleontologists have defined no faunal stage
s for the Holocene. If subdivision is necessary, periods of human technological development, such as the Mesolithic
, Neolithic
, and Bronze Age
, are usually used. However, the time periods referenced by these terms vary with the emergence of those technologies in different parts of the world.
Climatically, the Holocene may be divided evenly into the Hypsithermal
and Neoglacial
periods; the boundary coincides with the start of the Bronze Age
in European civilization. According to some scholars, a third division, the Anthropocene
, began in the 18th century.
Continental motions due to plate tectonics
are less than a kilometre over a span of only 10,000 years. However, ice melt caused world sea levels to rise about 35 m (110 ft) in the early part of the Holocene. 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 (600 ft) due to post-glacial rebound
over the late Pleistocene and Holocene, and are still rising today.
The sea level rise and temporary land depression allowed temporary marine incursions into areas that are now far from the sea. Holocene marine fossils are known from Vermont
, Quebec
, Ontario
, and Michigan
. Other than higher latitude temporary marine incursions associated with glacial depression, Holocene fossils are found primarily in lakebed, floodplain, and cave deposits. 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.
Post-glacial rebound in the Scandinavia
region resulted in the formation of the Baltic Sea
. The region continues to rise, still causing weak earthquake
s across Northern Europe
. 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.
Climate has been fairly stable over the Holocene. 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
. During the transition from last glacial to 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. It appears that this was influenced by the residual glacial ice remaining in the Northern Hemisphere
until the later date.
The hypsithermal
was a period of warming in which the global climate became warmer. However, the warming was probably not uniform across the world. This period ended about 5,500 years ago, when the earliest human civilizations in Africa
and Asia were just beginning to rise. This period of warmth ended with the descent into the Neoglacial. 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
. This was followed by the Little Ice Age
, from the 13th or 14th century to the mid 19th century, which was a period of significant cooling, though not everywhere as severe as previous times during neoglaciation.
The Holocene warming is an interglacial period and there is no reason to believe that it represents a permanent end to the current ice age
. However, the current global warming
may result in the Earth becoming warmer than the Eemian Stage, which peaked at roughly 125,000 years ago and was warmer than the Holocene. This prediction is sometimes referred to as a super-interglacial.
Compared to glacial conditions, habitable zones have expanded northwards, reaching their northernmost point during the hypsithermal. Greater moisture in the polar regions has caused the disappearance of steppe-tundra
.
s and mastodon
s, saber-toothed cat
s 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. This extinction of American megafauna
has been explained as caused by the arrival of the ancestors of Amerindians; though most scholars assert that climatic change also contributed, as well as a cometary bolide event over North America which is theorized to have triggered the Younger Dryas
.
Throughout the world, ecosystems in cooler climates that were previously regional have been isolated in higher altitude ecological "islands."
The 8.2 ka event
, an abrupt cold spell recorded as a negative excursion in the record lasting 400 years, is the most prominent climatic event occurring in the Holocene epoch, and may have marked a resurgence of ice cover. It is thought 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
.
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. 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 Jericho
in the Middle East
.
Both are followed by the aceramic Neolithic (Pre-Pottery Neolithic A
and Pre-Pottery Neolithic B
) and the pottery Neolithic
.
events
which occurred in the Holocene have been discovered in Europe, as well as in seas such as the Indian Ocean
and near remote Siberia
(Tunguska event
). It has been speculated that an impact effect such as that represented today by the Burckle crater
could have dramatically affected human culture in its early history by the creation of megatsunami
s, perhaps inspiring deluge
or inundation stories such as that of Noah's Flood.
Geologic time scale
The geologic time scale provides a system of chronologic measurement relating stratigraphy to time that is used by geologists, paleontologists and other earth scientists to describe the timing and relationships between events that have occurred during the history of the Earth...
epoch
Epoch (geology)
An epoch is a subdivision of the geologic timescale based on rock layering. In order, the higher subdivisions are periods, eras and eons. We are currently living in the Holocene epoch...
which began at the end of the Pleistocene (around 10,000 14C years
Radiocarbon dating
Radiocarbon dating is a radiometric dating method that uses the naturally occurring radioisotope carbon-14 to estimate the age of carbon-bearing materials up to about 58,000 to 62,000 years. Raw, i.e. uncalibrated, radiocarbon ages are usually reported in radiocarbon years "Before Present" ,...
ago) and continues to the present. The Holocene is part of the Quaternary
Quaternary
The Quaternary Period is the most recent of the three periods of the Cenozoic Era in the geologic time scale of the ICS. It follows the Neogene Period, spanning 2.588 ± 0.005 million years ago to the present...
period. Its name comes from the Greek
Greek language
Greek is an independent branch of the Indo-European family of languages. Native to the southern Balkans, it has the longest documented history of any Indo-European language, spanning 34 centuries of written records. Its writing system has been the Greek alphabet for the majority of its history;...
words (holos, whole or entire) and (kainos, new), meaning "entirely recent". It has been identified with the current warm period, known as MIS 1
Marine isotope stage
Marine isotope stages , marine oxygen-isotope stages, or oxygen isotope stages , are alternating warm and cool periods in the Earth's paleoclimate, deduced from oxygen isotope data reflecting changes in temperature derived from data from deep sea core samples...
and based on that past evidence, can be considered an interglacial
Interglacial
An Interglacial period is a geological interval of warmer global average temperature lasting thousands of years that separates consecutive glacial periods within an ice age...
in the current ice age
Quaternary glaciation
Quaternary glaciation, also known as the Pleistocene glaciation, the current ice age or simply the ice age, refers to the period of the last few million years in which permanent ice sheets were established in Antarctica and perhaps Greenland, and fluctuating ice sheets have occurred elsewhere...
.
The Holocene also encompasses within it the growth and impacts of the human species world-wide, including all its written history and overall significant transition toward urban living in the present. Given these, a new synonym Anthropocene
Anthropocene
The Anthropocene is a recent and informal geologic chronological term that serves to mark the evidence and extent of human activities that have had a significant global impact on the Earth's ecosystems...
, is specifically proposed and used for the time period since approximately synchronous lithospheric evidence, or more recently atmospheric evidence, of human impacts have been found on the Earth
Earth
Earth is the third planet from the Sun, and the densest and fifth-largest of the eight planets in the Solar System. It is also the largest of the Solar System's four terrestrial planets...
and its ecosystem
Ecosystem
An ecosystem is a biological environment consisting of all the organisms living in a particular area, as well as all the nonliving , physical components of the environment with which the organisms interact, such as air, soil, water and sunlight....
s; these impacts may be considered of global significance for future evolution of living species.
Overview
It is generally accepted that the Holocene started approximately 12,000 years BP (before present day)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...
, i.e., around 10,000 BC. The period follows the last glacial period (regionally known as the Wisconsinan Glacial Period, the Baltic-Scandinavian Ice Age, or the Weichsel glacial). The Holocene can be subdivided into five time intervals, or chronozone
Chronozone
A chronozone or chron is a slice of time that begins at a given identifiable event and ends at another. In the fossil record such tracer events are usually keyed to disappearance of a widely distributed and rapidly changing species or the appearance of such a species in the geological record...
s, based on climatic fluctuations:
- Preboreal (10 ka – 9 ka),
- BorealBoreal (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...
(9 ka – 8 ka), - AtlanticAtlantic (period)The Atlantic in palaeoclimatology was the warmest and moistest Blytt-Sernander period, pollen zone and chronozone of Holocene northern Europe. The climate was generally warmer than today. It was preceded by the Boreal, with a climate similar to today’s, and was followed by the Sub-Boreal, a...
(8 ka – 5 ka), - Subboreal (5 ka – 2.5 ka) and
- Subatlantic (2.5 ka – present).
- Note: "ka" means "thousand years" (non-calibrated C14 dates)
The Blytt-Sernander
Blytt-Sernander
The Blytt-Sernander classification, or sequence, is a series of north European climatic periods or phases based on the study of Danish peat bogs by Axel Blytt and Rutger Sernander...
classification of climatic periods defined, initially, by plant remains in peat mosses, is now of purely historical interest. The scheme was defined for north Europe, but the climate change
Climate change
Climate change is a significant and lasting change in the statistical distribution of weather patterns over periods ranging from decades to millions of years. It may be a change in average weather conditions or the distribution of events around that average...
s were claimed to occur more widely. 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
Prehistory
Prehistory is the span of time before recorded history. Prehistory can refer to the period of human existence before the availability of those written records with which recorded history begins. More broadly, it refers to all the time preceding human existence and the invention of writing...
.
Paleontologists have defined no faunal stage
Faunal stage
In chronostratigraphy, a stage is a succession of rock strata laid down in a single age on the geologic timescale, which usually represents millions of years of deposition. A given stage of rock and the corresponding age of time will by convention have the same name, and the same boundaries.Rock...
s for the Holocene. If subdivision is necessary, periods of human technological development, such as the Mesolithic
Mesolithic
The Mesolithic is an archaeological concept used to refer to certain groups of archaeological cultures defined as falling between the Paleolithic and the Neolithic....
, Neolithic
Neolithic
The Neolithic Age, Era, or Period, or New Stone Age, was a period in the development of human technology, beginning about 9500 BC in some parts of the Middle East, and later in other parts of the world. It is traditionally considered as the last part of the Stone Age...
, and Bronze Age
Bronze Age
The Bronze Age is a period characterized by the use of copper and its alloy bronze as the chief hard materials in the manufacture of some implements and weapons. Chronologically, it stands between the Stone Age and Iron Age...
, are usually used. However, the time periods referenced by these terms vary with the emergence of those technologies in different parts of the world.
Climatically, the Holocene may be divided evenly into the Hypsithermal
Holocene climatic optimum
The Holocene Climate Optimum was a warm period during roughly the interval 9,000 to 5,000 years B.P.. This event has also been known by many other names, including: Hypsithermal, Altithermal, Climatic Optimum, Holocene Optimum, Holocene Thermal Maximum, and Holocene Megathermal.This warm period...
and Neoglacial
Neoglaciation
The neoglaciation describes the documented cooling trend in the Earth's climate during the Holocene, following the retreat of the Wisconsin glaciation, the most recent glacial period. Neoglaciation has followed the hypsithermal or Holocene Climatic Optimum, the warmest point in the Earth's climate...
periods; the boundary coincides with the start of the Bronze Age
Bronze Age
The Bronze Age is a period characterized by the use of copper and its alloy bronze as the chief hard materials in the manufacture of some implements and weapons. Chronologically, it stands between the Stone Age and Iron Age...
in European civilization. According to some scholars, a third division, the Anthropocene
Anthropocene
The Anthropocene is a recent and informal geologic chronological term that serves to mark the evidence and extent of human activities that have had a significant global impact on the Earth's ecosystems...
, began in the 18th century.
Geology
Plate tectonics
Plate tectonics is a scientific theory that describes the large scale motions of Earth's lithosphere...
are less than a kilometre over a span of only 10,000 years. However, ice melt caused world sea levels to rise about 35 m (110 ft) in the early part of the Holocene. In addition, many areas above about 40 degrees north
40th parallel north
The 40th parallel north is a circle of latitude that is 40 degrees north of the Earth's equatorial plane. It crosses Europe, the Mediterranean Sea, Asia, the Pacific Ocean, North America, and the Atlantic Ocean....
latitude had been depressed by the weight of the Pleistocene glaciers and rose as much as 180 m (600 ft) due to post-glacial rebound
Post-glacial rebound
Post-glacial rebound is the rise of land masses that were depressed by the huge weight of ice sheets during the last glacial period, through a process known as isostasy...
over the late Pleistocene and Holocene, and are still rising today.
The sea level rise and temporary land depression allowed temporary marine incursions into areas that are now far from the sea. Holocene marine fossils are known from Vermont
Vermont
Vermont is a state in the New England region of the northeastern United States of America. The state ranks 43rd in land area, , and 45th in total area. Its population according to the 2010 census, 630,337, is the second smallest in the country, larger only than Wyoming. It is the only New England...
, Quebec
Quebec
Quebec or is a province in east-central Canada. It is the only Canadian province with a predominantly French-speaking population and the only one whose sole official language is French at the provincial level....
, Ontario
Ontario
Ontario is a province of Canada, located in east-central Canada. It is Canada's most populous province and second largest in total area. It is home to the nation's most populous city, Toronto, and the nation's capital, Ottawa....
, and Michigan
Michigan
Michigan is a U.S. state located in the Great Lakes Region of the United States of America. The name Michigan is the French form of the Ojibwa word mishigamaa, meaning "large water" or "large lake"....
. Other than higher latitude temporary marine incursions associated with glacial depression, Holocene fossils are found primarily in lakebed, floodplain, and cave deposits. Holocene marine deposits along low-latitude coastlines are rare because the rise in sea levels during the period exceeds any likely tectonic uplift
Tectonic uplift
Tectonic uplift is a geological process most often caused by plate tectonics which increases elevation. The opposite of uplift is subsidence, which results in a decrease in elevation. Uplift may be orogenic or isostatic.-Orogenic uplift:...
of non-glacial origin.
Post-glacial rebound in the Scandinavia
Scandinavia
Scandinavia is a cultural, historical and ethno-linguistic region in northern Europe that includes the three kingdoms of Denmark, Norway and Sweden, characterized by their common ethno-cultural heritage and language. Modern Norway and Sweden proper are situated on the Scandinavian Peninsula,...
region resulted in the formation of the Baltic Sea
Baltic Sea
The Baltic Sea is a brackish mediterranean sea located in Northern Europe, from 53°N to 66°N latitude and from 20°E to 26°E longitude. It is bounded by the Scandinavian Peninsula, the mainland of Europe, and the Danish islands. It drains into the Kattegat by way of the Øresund, the Great Belt and...
. The region continues to rise, still causing weak earthquake
Earthquake
An earthquake is the result of a sudden release of energy in the Earth's crust that creates seismic waves. The seismicity, seismism or seismic activity of an area refers to the frequency, type and size of earthquakes experienced over a period of time...
s across Northern Europe
Northern Europe
Northern Europe is the northern part or region of Europe. Northern Europe typically refers to the seven countries in the northern part of the European subcontinent which includes Denmark, Estonia, Latvia, Lithuania, Norway, Finland and Sweden...
. The equivalent event in North America
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...
was the rebound of Hudson Bay
Hudson Bay
Hudson Bay , sometimes called Hudson's Bay, is a large body of saltwater in northeastern Canada. It drains a very large area, about , that includes parts of Ontario, Quebec, Saskatchewan, Alberta, most of Manitoba, southeastern Nunavut, as well as parts of North Dakota, South Dakota, Minnesota,...
, as it shrank from its larger, immediate post-glacial Tyrrell Sea
Tyrrell Sea
The Tyrrell Sea, named for Canadian geologist Joseph Tyrrell, is another name for prehistoric Hudson Bay, namely as it existed during the retreat of the Laurentide Ice Sheet....
phase, to near its present boundaries.
Climate
Ice core
An ice core is a core sample that is typically removed from an ice sheet, most commonly from the polar ice caps of Antarctica, Greenland or from high mountain glaciers elsewhere. As the ice forms from the incremental build up of annual layers of snow, lower layers are older than upper, and an ice...
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
Younger Dryas
The Younger Dryas stadial, also referred to as the Big Freeze, was a geologically brief period of cold climatic conditions and drought between approximately 12.8 and 11.5 ka BP, or 12,800 and 11,500 years before present...
. During the transition from last glacial to holocene, the Huelmo/Mascardi Cold Reversal
Huelmo/Mascardi Cold Reversal
The Huelmo/Mascardi Cold Reversal is the name given to a cooling event in South America between 11,400 and 10,200 14C years BP. This cooling began about 550 years before the Younger Dryas cooling in the Northern Hemisphere, and both periods ended at about the same time.The event was given its...
in the Southern Hemisphere
Southern Hemisphere
The Southern Hemisphere is the part of Earth that lies south of the equator. The word hemisphere literally means 'half ball' or "half sphere"...
began before the Younger Dryas, and the maximum warmth flowed south to north from 11,000 to 7,000 years ago. It appears that this was influenced by the residual glacial ice remaining in the Northern Hemisphere
Northern Hemisphere
The Northern Hemisphere is the half of a planet that is north of its equator—the word hemisphere literally means “half sphere”. It is also that half of the celestial sphere north of the celestial equator...
until the later date.
The hypsithermal
Holocene climatic optimum
The Holocene Climate Optimum was a warm period during roughly the interval 9,000 to 5,000 years B.P.. This event has also been known by many other names, including: Hypsithermal, Altithermal, Climatic Optimum, Holocene Optimum, Holocene Thermal Maximum, and Holocene Megathermal.This warm period...
was a period of warming in which the global climate became warmer. However, the warming was probably not uniform across the world. This period ended about 5,500 years ago, when the earliest human civilizations in Africa
Africa
Africa is the world's second largest and second most populous continent, after Asia. At about 30.2 million km² including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area...
and Asia were just beginning to rise. This period of warmth ended with the descent into the Neoglacial. 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
Medieval Warm Period
The Medieval Warm Period , Medieval Climate Optimum, or Medieval Climatic Anomaly was a time of warm climate in the North Atlantic region, that may also have been related to other climate events around the world during that time, including in China, New Zealand, and other countries lasting from...
. This was followed by the Little Ice Age
Little Ice Age
The Little Ice Age was a period of cooling that occurred after the Medieval Warm Period . While not a true ice age, the term was introduced into the scientific literature by François E. Matthes in 1939...
, from the 13th or 14th century to the mid 19th century, which was a period of significant cooling, though not everywhere as severe as previous times during neoglaciation.
The Holocene warming is an interglacial period and there is no reason to believe that it represents a permanent end to the current ice age
Quaternary glaciation
Quaternary glaciation, also known as the Pleistocene glaciation, the current ice age or simply the ice age, refers to the period of the last few million years in which permanent ice sheets were established in Antarctica and perhaps Greenland, and fluctuating ice sheets have occurred elsewhere...
. However, the current global warming
Global warming
Global warming refers to the rising average temperature of Earth's atmosphere and oceans and its projected continuation. In the last 100 years, Earth's average surface temperature increased by about with about two thirds of the increase occurring over just the last three decades...
may result in the Earth becoming warmer than the Eemian Stage, which peaked at roughly 125,000 years ago and was warmer than the Holocene. This prediction is sometimes referred to as a super-interglacial.
Compared to glacial conditions, habitable zones have expanded northwards, reaching their northernmost point during the hypsithermal. Greater moisture in the polar regions has caused the disappearance of steppe-tundra
Steppe-tundra
Steppe-tundra is a very cold dry-climate vegetation type consisting of mostly treeless open herbaceous vegetation. it was widespread during Pleistocene times at mid-latitudes of North America and Eurasia. Steppe-tundra can be divided into two types...
.
Ecological developments
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. A number of large animals including mammothMammoth
A mammoth is any species of the extinct genus Mammuthus. These proboscideans are members of Elephantidae, the family of elephants and mammoths, and close relatives of modern elephants. They were often equipped with long curved tusks and, in northern species, a covering of long hair...
s and mastodon
Mastodon
Mastodons were large tusked mammal species of the extinct genus Mammut which inhabited Asia, Africa, Europe, North America and Central America from the Oligocene through Pleistocene, 33.9 mya to 11,000 years ago. The American mastodon is the most recent and best known species of the group...
s, saber-toothed cat
Saber-toothed cat
Saber-toothed cat or Sabre-toothed cat refers to the extinct subfamilies of Machairodontinae , Barbourofelidae , and Nimravidae as well as two families related to marsupials that were found worldwide from the Eocene Epoch to the end of the Pleistocene Epoch ,...
s like Smilodon
Smilodon
Smilodon , often called a saber-toothed cat or saber-toothed tiger, is an extinct genus of machairodonts. This saber-toothed cat was endemic to North America and South America, living from near the beginning through the very end of the Pleistocene epoch .-Etymology:The nickname "saber-tooth" refers...
and Homotherium
Homotherium
Homotherium is an extinct genus of machairodontine saber-toothed cats, often termed scimitar cats, endemic to North America, South America, Europe, Asia, and Africa during the Pliocene and Pleistocene epochs , existing for approximately .It first became extinct in Africa some 1.5 million years ago...
, 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. This extinction of American megafauna
Megafauna
In terrestrial zoology, megafauna are "giant", "very large" or "large" animals. The most common thresholds used are or...
has been explained as caused by the arrival of the ancestors of Amerindians; though most scholars assert that climatic change also contributed, as well as a cometary bolide event over North America which is theorized to have triggered the Younger Dryas
Younger Dryas
The Younger Dryas stadial, also referred to as the Big Freeze, was a geologically brief period of cold climatic conditions and drought between approximately 12.8 and 11.5 ka BP, or 12,800 and 11,500 years before present...
.
Throughout the world, ecosystems in cooler climates that were previously regional have been isolated in higher altitude ecological "islands."
The 8.2 ka event
8.2 kiloyear event
The 8.2 kiloyear event is the term that climatologists have adopted for a sudden decrease in global temperatures that occurred approximately 8,200 years before the present, or c. 6,200 BCE, and which lasted for the next two to four centuries...
, an abrupt cold spell recorded as a negative excursion in the record lasting 400 years, is the most prominent climatic event occurring in the Holocene epoch, and may have marked a resurgence of ice cover. It is thought that this event was caused by the final drainage of Lake Agassiz
Lake Agassiz
Lake Agassiz was an immense glacial lake located in the center of North America. Fed by glacial runoff at the end of the last glacial period, its area was larger than all of the modern Great Lakes combined, and it held more water than contained by all lakes in the world today.-Conception:First...
, which had been confined by the glaciers, disrupting the thermohaline circulation of the Atlantic
Atlantic Ocean
The Atlantic Ocean is the second-largest of the world's oceanic divisions. With a total area of about , it covers approximately 20% of the Earth's surface and about 26% of its water surface area...
.
Human developments
The beginning of the Holocene corresponds with the beginning of the MesolithicMesolithic
The Mesolithic is an archaeological concept used to refer to certain groups of archaeological cultures defined as falling between the Paleolithic and the Neolithic....
age in most of Europe
Europe
Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...
; but in regions such as the Middle East
Middle East
The Middle East is a region that encompasses Western Asia and Northern Africa. It is often used as a synonym for Near East, in opposition to Far East...
and Anatolia
Anatolia
Anatolia is a geographic and historical term denoting the westernmost protrusion of Asia, comprising the majority of the Republic of Turkey...
with a very early neolithisation, Epipaleolithic
Epipaleolithic
The Epipaleolithic Age was a period in the development of human technology marked by more advanced stone blades and other tools than the earlier Paleolithic age, although still before the development of agriculture in the Neolithic age...
is preferred in place of Mesolithic. Cultures in this period include: Hamburgian
Hamburg culture
The Hamburg culture was a Late Upper Paleolithic culture of reindeer hunters in northwestern Europe during the last part of the Weichsel Glaciation and beginning of the Meiendorf Interstadial...
, Federmesser
Federmesser culture
The Federmesser culture is a toolmaking tradition of the late Upper Palaeolithic era, of the Northern European Plain dating to between c. 9800 and 8800 BC...
, and the Natufian culture
Natufian culture
The Natufian culture was a Mesolithic culture that existed from 12,500 to 9,500 BC in the Levant, a region in the Eastern Mediterranean. It was unusual in that it was sedentary, or semi-sedentary, before the introduction of agriculture...
, during which the oldest inhabited places still existing on Earth were first settled, such as Jericho
Jericho
Jericho ; is a city located near the Jordan River in the West Bank of the Palestinian territories. It is the capital of the Jericho Governorate and has a population of more than 20,000. Situated well below sea level on an east-west route north of the Dead Sea, Jericho is the lowest permanently...
in the Middle East
Middle East
The Middle East is a region that encompasses Western Asia and Northern Africa. It is often used as a synonym for Near East, in opposition to Far East...
.
Both are followed by the aceramic Neolithic (Pre-Pottery Neolithic A
Pre-Pottery Neolithic A
Pre-Pottery Neolithic A denotes the first stage in early Levantine Neolithic culture, dating around 9500 to 8500 BC. Archaeological remains are located in the Levantine and upper Mesopotamian region of the Fertile Crescent...
and Pre-Pottery Neolithic B
Pre-Pottery Neolithic B
Pre-Pottery Neolithic B is a division of the Neolithic developed by Dame Kathleen Kenyon during her archaeological excavations at Jericho in the southern Levant region....
) and the pottery Neolithic
Neolithic
The Neolithic Age, Era, or Period, or New Stone Age, was a period in the development of human technology, beginning about 9500 BC in some parts of the Middle East, and later in other parts of the world. It is traditionally considered as the last part of the Stone Age...
.
Impact events
Many meteoriteMeteorite
A meteorite is a natural object originating in outer space that survives impact with the Earth's surface. Meteorites can be big or small. Most meteorites derive from small astronomical objects called meteoroids, but they are also sometimes produced by impacts of asteroids...
events
Impact event
An impact event is the collision of a large meteorite, asteroid, comet, or other celestial object with the Earth or another planet. Throughout recorded history, hundreds of minor impact events have been reported, with some occurrences causing deaths, injuries, property damage or other significant...
which occurred in the Holocene have been discovered in Europe, as well as in seas such as the Indian Ocean
Indian Ocean
The Indian Ocean is the third largest of the world's oceanic divisions, covering approximately 20% of the water on the Earth's surface. It is bounded on the north by the Indian Subcontinent and Arabian Peninsula ; on the west by eastern Africa; on the east by Indochina, the Sunda Islands, and...
and near remote Siberia
Siberia
Siberia is an extensive region constituting almost all of Northern Asia. Comprising the central and eastern portion of the Russian Federation, it was part of the Soviet Union from its beginning, as its predecessor states, the Tsardom of Russia and the Russian Empire, conquered it during the 16th...
(Tunguska event
Tunguska event
The Tunguska event, or Tunguska blast or Tunguska explosion, was an enormously powerful explosion that occurred near the Podkamennaya Tunguska River in what is now Krasnoyarsk Krai, Russia, at about 7:14 a.m...
). It has been speculated that an impact effect such as that represented today by the Burckle crater
Burckle Crater
Burckle Crater is a hypothesized undersea crater that has been proposed by the Holocene Impact Working Group. They considered that it likely was formed by a very large scale and relatively recent comet or meteorite impact event...
could have dramatically affected human culture in its early history by the creation of megatsunami
Megatsunami
Megatsunami is an informal term to describe a tsunami that has initial wave heights that are much larger than normal tsunamis...
s, perhaps inspiring deluge
Deluge (prehistoric)
In geomorphology, an outburst flood, which is a type of megaflood, is a high magnitude, low frequency catastrophic flood involving the sudden release of water. During the last deglaciation, numerous glacial lake outburst floods were caused by the collapse of either ice sheets or glaciers that...
or inundation stories such as that of Noah's Flood.
See also
- 8.2 kiloyear event8.2 kiloyear eventThe 8.2 kiloyear event is the term that climatologists have adopted for a sudden decrease in global temperatures that occurred approximately 8,200 years before the present, or c. 6,200 BCE, and which lasted for the next two to four centuries...
- AnthropoceneAnthropoceneThe Anthropocene is a recent and informal geologic chronological term that serves to mark the evidence and extent of human activities that have had a significant global impact on the Earth's ecosystems...
- Blytt-SernanderBlytt-SernanderThe Blytt-Sernander classification, or sequence, is a series of north European climatic periods or phases based on the study of Danish peat bogs by Axel Blytt and Rutger Sernander...
- Deluge (prehistoric)Deluge (prehistoric)In geomorphology, an outburst flood, which is a type of megaflood, is a high magnitude, low frequency catastrophic flood involving the sudden release of water. During the last deglaciation, numerous glacial lake outburst floods were caused by the collapse of either ice sheets or glaciers that...
- Holocene calendarHolocene calendarThe Human Era, also known as the Holocene calendar or Holocene era , is a year numbering system that adds exactly 10,000 years to the currently world-dominant Anno Domini and Common Era system, placing its first year near the beginning of the Holocene epoch and the Neolithic revolution...
– used to date geological, archaeological, dendrochronological and historical events from the approximate beginning of the Holocene Epoch - Holocene extinction
- Holocene Impact Working GroupHolocene Impact Working GroupThe Holocene Impact Working Group is a group of scientists from Australia, France, Ireland, Russia and the USA who hypothesize that meteorite impacts on Earth are more common than previously supposed....
- Neolithic SubpluvialNeolithic SubpluvialThe Neolithic Subpluvial — sometimes called the Holocene Wet Phase — was an extended period of wet and rainy conditions in the climate history of northern Africa...
- Older PeronOlder PeronThe Older Peron transgression was a period of unusually warm climate during the Holocene Epoch. It began in the 5000 BCE to 4900 BCE era, and lasted to about 4100 BCE...
- Piora OscillationPiora OscillationThe Piora Oscillation was an abrupt cold and wet period in the climate history of the Holocene Epoch; it is generally dated to the period of c. 3200 to 2900 BCE...
- 10th millennium BC10th millennium BCThe 10th millennium BC marks the beginning of the Mesolithic and Epipaleolithic period, which is the first part of the Holocene epoch. Agriculture, based on the cultivation of primitive forms of millet and rice, occurred in Southwest Asia...
- Last Glacial MaximumLast Glacial MaximumThe Last Glacial Maximum refers to a period in the Earth's climate history when ice sheets were at their maximum extension, between 26,500 and 19,000–20,000 years ago, marking the peak of the last glacial period. During this time, vast ice sheets covered much of North America, northern Europe and...