NationMaster - Encyclopedia: PETM

The end of the Paleocene (55.5 to 54.8 Mya) was marked by one of the most significant periods of global change during the Cenozoic Era. A sudden global climate change, the Paleocene-Eocene Thermal Maximum (PETM), upset oceanic and atmospheric circulation, leading to the extinction of numerous deep-sea benthic foraminifera and a major turnover in mammalian life on land that marked the emergence of mammalian lines recognizable today. Image File history File links // Description Expanded view of climate change during the last five million years, showing the rapid oscillations in the glacial state. ... Image File history File links // Description Expanded view of climate change during the last five million years, showing the rapid oscillations in the glacial state. ... The Paleocene, early dawn of the recent, is a geologic epoch that lasted from 65. ... The Cenozoic Era (IPA pronunciation: ); sometimes Caenozoic Era (in the United Kingdom), meaning new life (Greek (kainos), new, and (zoe), life), is the most recent of the three classic geological eras. ... Variations in CO2, temperature and dust from the Vostok ice core over the last 400,000 years For current global climate change, see Global warming. ... The Dodo, shown here in illustration, is an often-cited[1] example of modern extinction. ... In oceanography, marine geology and biology, benthos are the organisms and habitats of the sea floor; in freshwater biology they are the organisms and habitats of the bottoms of lakes, rivers, and creeks. ... Orders Allogromiida Carterinida Fusulinida - extinct Globigerinida Involutinida - extinct Lagenida Miliolida Robertinida Rotaliida Silicoloculinida Spirillinida Textulariida incertae sedis Xenophyophorea Reticulomyxa The Foraminifera, or forams for short, are a large group of amoeboid protists with reticulating pseudopods, fine strands that branch and merge to form a dynamic net. ... Orders Subclass Monotremata Monotremata Subclass Marsupialia Didelphimorphia Paucituberculata Microbiotheria Dasyuromorphia Peramelemorphia Notoryctemorphia Diprotodontia Subclass Placentalia Xenarthra Dermoptera Desmostylia Scandentia Primates Rodentia Lagomorpha Insectivora Chiroptera Pholidota Carnivora Perissodactyla Artiodactyla Cetacea Afrosoricida Macroscelidea Tubulidentata Hyracoidea Proboscidea Sirenia The mammals are the class of vertebrate animals primarily characterized by the presence of mammary...

In an event marking the start of the Eocene, the planet heated up in one of the most rapid and extreme global warming events recorded in geologic history, currently identified as the 'Paleocene-Eocene Thermal Maximum' or the 'Initial Eocene Thermal Maximum' (PETM or IETM). Sea surface temperatures rose between 5 and 8°C over a period of a few thousand years, and in the high Arctic, sea surface temperatures rose to a sub-tropical 23°C/73°F.^[1] In 1990, marine scientists James Kennett and Lowell Stott, both then at the University of California, Santa Barbara, reported analysis of marine sediments showing that, not only had the surface of the Arctic ocean heated up about 10 degrees at the beginning of the Eocene, but that the entire depth of the ocean had warmed, dramatically changing its chemistry. Oxygen content in deep sea waters was dramatically reduced, causing 30 to 40% of deep sea foraminifera to go extinct. Geologist Jim Zachos of the University of California, Santa Cruz connected the Eocene heat wave to drastic changes in ocean chemistry that caused the massive worldwide die-off.^[2] hfajhfiudshfas == == == --24. ... The University of California, Santa Barbara (UCSB) is a coeducational public university located on the Pacific Ocean in Santa Barbara County, California, USA. It is one out of 10 campuses of the University of California. ... Animated map exhibiting the worlds oceanic waters. ... Sediment is any particulate matter that can be transported by fluid flow and which eventually is deposited as a layer of solid particles on the bed or bottom of a body of water or other liquid. ... The University of California, Santa Cruz, also known as UCSC or UC Santa Cruz, is one of the ten campuses of the University of California. ...

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The cause of the PETM is unclear. Reservoirs of methane gas trapped in clathrates may have been released by warmer temperatures, and the thermal combustion of sedimentary organic matter and peat deposits may have contributed to an increase in global warming gasses leading to the rise in temperatures. An alternative theory proposes that a comet impact triggered the PETM. A clathrate or clathrate compound is a chemical substance consisting of a Greek klethra, meaning bars (in the sense of a lattice). ...

Tracking the ratio of carbon isotopes in marine calcium carbonate sediments, Kennett and Stott found a sharp decrease in the amount of heavy carbon in 55-million-year-old marine fossils, a decline that caused the relative ratio of C-13 to C-12 to plunge^[3]. A synchronous drop in carbon isotope ratios in many terrestrial environments has also been identified^[4], indicating that a gas with very low amounts of heavy C-13 appears to have flooded the atmosphere. In 1995, Gerald Dickens of the University of Michigan argued that only methane gas had enough light carbon to produce the early Eocene plunge. Submarine clathrates that trap methane hydrate, a form of methane 'ice' that forms in cold water under great pressure, are widely distributed and plentiful in sediments on the outer edges of continental margins. As the Earth warmed during the Paleocene, melting of methane hydrates could have caused a 'belch' of methane from clathrate ice in seafloor sediments^[5]. Subtropical Arctic Ocean temperatures during the Palaeocene/Eocene thermal maximum. Nature, 441(7093): 610-613. With a global warming potential (GWP) over a 100-year period of 23 ^[6], a massive sublimation and release of sedimentary methane hydrates into the ocean-atmosphere reservoir would have upset the global carbon cycle and led to runaway global warming. Isotopes are any of the several different forms of an element each having different atomic mass (mass number). ... Calcium carbonate is a chemical compound, with chemical formula CaCO3. ... FOSSIL is a standard for allowing serial communication for telecommunications programs under DOS. FOSSIL is an acronym for Fido Opus Seadog Standard Interface Layer. ... General Name, Symbol, Number carbon, C, 6 Chemical series nonmetals Group, Period, Block 14, 2, p Appearance black (graphite) colorless (diamond) Standard atomic weight 12. ... Isotopes are any of the several different forms of an element each having different atomic mass (mass number). ... The University of Michigan, Ann Arbor (UM, U of M or U-M) is a coeducational public research university in the state of Michigan. ... Methane is a chemical compound with the molecular formula CH4. ... A clathrate or clathrate compound is a chemical substance consisting of a Greek klethra, meaning bars (in the sense of a lattice). ... Burning ice. Methane released by heating burns, water drips. ... Global warming potential (GWP) is a measure of how much a given mass of greenhouse gas is estimated to contribute to global warming. ... Sublimation of an element or compound is the change from a solid directly to a gas with no intermediate liquid stage. ... The carbon cycle is the biogeochemical cycle by which carbon is exchanged between the biosphere, geosphere, hydrosphere,and atmosphere of the Earth (other astronomical objects may have similar carbon cycles, but nothing is yet known about them). ... Global mean surface temperatures 1850 to 2006 Mean surface temperature anomalies during the period 1995 to 2004 with respect to the average temperatures from 1940 to 1980 Global warming is the observed increase in the average temperature of the Earths atmosphere and oceans in recent decades and the projected...

Scientists Flavia Nunes and Richard Norris of the Scripps Institution of Oceanography in California explored how these warmer temperatures might have affected ocean currents. They measured carbon-13 isotopes from fourteen cores that had been drilled into the deep floor in four different ocean basins, taking samples from sediment layers deposited before, during, and after the PETM. The lighter isotope, preferred by living organisms, offers an indicator of the nutrients available in the water at the time. The higher the isotope-ratio value, the likelier that the carbon source came from the deep ocean, the prime source for nutrients for marine life. With a detailed reconstruction, Nunes and Norris found that the world's ocean current system changed during the PETM, in effect reversing itself. Before the PETM, deep water upwelled in the southern hemisphere; over about 40,000 years, the source of this upwelling shifted to the northern hemisphere, where it took another 100,000 years before recovering completely.

In the atmosphere, methane breaks down and releases carbon dioxide. According to Zachos and Dickens, during the PETM methane combined with oxygen in the air and water, forming carbon dioxide and essentially suffocating marine life. Whether volcanic activity or a methane belch was the culprit, greenhouse gasses locked in the sun's warmth, sending global temperatures soaring. This article is about volcanoes in geology. ...

Dissolved in the oceans, the added carbon dioxide also increased the overall acidity of seawater. This in turn would increase the rate of dissolution of calcite shells of microplankton, which are the dominant component of seafloor sediments, leaving behind only nonsoluble clays. Indeed, a documented change in colors of the sediment, from bright white carbonates to deep red clays, marks the Paleocene-Eocene event. Normal deposition of microscopic carbonate foram shells on the deeper reaches of the seafloor did not resume for at least 50,000 years, and the total recovery time to a "normal state" took roughly 100,000 years.^[2] Acidity is a controversial novelette written for the popular South Asian website Chowk. ... Doubly refracting Calcite from Iceberg claim, Dixon, New Mexico. ... The Gay Head cliffs in Marthas Vineyard are made almost entirely of clay. ... Orders Allogromiida Carterinida Fusulinida- extinct Globigerinida Involutinida- extinct Lagenida Miliolida Robertinida Rotaliida Silicoloculinida Spirillinida Textulariida incertae sedis Xenophyophorea Reticulomyxa The Foraminifera, or forams for short, are a large group of amoeboid protists with reticulating pseudopods, fine strands that branch and merge to form a dynamic net. ...

At the start of the Eocene, the Earth remained warm for about 80,000 to 200,000 years. On land, there was a massive turnover of mammals, in which most of the primitive mammals that had developed since the end of the Cretaceous Period were suddenly replaced by the ancestors of most of the surviving modern mammal groups, all of them in small versions which were adapted to Eocene heat. Plant life was characterised by boreotropical flora, with extensive high-latitude forests composed of large, fast-growing trees, such as the Dawn Redwood, found as far as 80°N. In 2005, Dutch scientists studying material from the Arctic Coring Expedition found fossilized algae characteristic of subtropical waters averaging about 20°C in sediment cores taken on the Lomonosov Ridge between Siberia and Greenland, where the current average temperature is -1.5°C. Atmospheric carbon levels during the period are thought to have been about 2,000-3,000 parts per million (ppm), compared with 380 ppm today. Orders Subclass Monotremata Monotremata Subclass Marsupialia Didelphimorphia Paucituberculata Microbiotheria Dasyuromorphia Peramelemorphia Notoryctemorphia Diprotodontia Subclass Placentalia Xenarthra Dermoptera Desmostylia Scandentia Primates Rodentia Lagomorpha Insectivora Chiroptera Pholidota Carnivora Perissodactyla Artiodactyla Cetacea Afrosoricida Macroscelidea Tubulidentata Hyracoidea Proboscidea Sirenia The mammals are the class of vertebrate animals primarily characterized by the presence of mammary... The Cretaceous Period is one of the major divisions of the geologic timescale, reaching from the end of the Jurassic Period (i. ... Boreotropical flora were plants that may have formed a belt of vegetation around the Northern Hemisphere during the Eocene epoch. ... Latitude, usually denoted symbolically by the Greek letter phi, , gives the location of a place on Earth north or south of the equator. ... Temperate rainforest on Northern Slopes of the Alborz mountain ranges, Iran A dense growth of softwoods (a conifer forest) in the Sierra Nevada Range of Northern California A deciduous broadleaf (Beech) forest in Slovenia. ... Binomial name Metasequoia glyptostroboides The Dawn Redwood (Metasequoia glyptostroboides) is a fast growing tree in the conifer family Cupressaceae native to the Sichuan-Hubei region of China. ... Lomonosov Ridge (Ð¥Ñ€ÐµÐ±ÐµÑ‚ Ð›Ð¾Ð¼Ð¾Ð½Ð¾ÑÐ¾Ð²Ð° in Russian) is an underwater oceanic ridge in the Arctic Ocean. ...

A recent study of sediment cores from the Atlantic Archives revealed that between 2000 and 5000 gigatons of carbon was released into the atmosphere during the period. Using Argon 40/39 dating, the release of gas is theorized to have happened over a 10,000 to 20,000 year period. A close correlation between carbon release and the Paleocene-Eocene Thermal Maximum was observed^[7]. General Name, Symbol, Number carbon, C, 6 Chemical series nonmetals Group, Period, Block 14, 2, p Appearance black (graphite) colorless (diamond) Standard atomic weight 12. ... General Name, Symbol, Number argon, Ar, 18 Chemical series noble gases Group, Period, Block 18, 3, p Appearance colorless Atomic mass 39. ...

Recently, several other rapid global warming events have been recorded in slightly younger sediments, of which one has been named after Sesame Street character Elmo.^[8] These events appear to have been similar to the PETM, but of smaller magnitude. Elmo Elmo is a Muppet on the childrens television show Sesame Street. ...

The sudden release of oceanic methane hydrate has also been hypothesized as a potential cause of the Permian-Triassic extinction event. This is of serious concern for contemporary global warming and climate change theorists (see clathrate gun hypothesis). Burning ice. Methane released by heating burns, water drips. ... The Permian-Triassic (P-T or PT) extinction event, sometimes informally called the Great Dying, was an extinction event that occurred approximately 251 million years ago (mya), forming the boundary between the Permian and Triassic geologic periods. ... Global mean surface temperatures 1850 to 2006 Mean surface temperature anomalies during the period 1995 to 2004 with respect to the average temperatures from 1940 to 1980 Global warming is the observed increase in the average temperature of the Earths atmosphere and oceans in recent decades and the projected... Variations in CO2, temperature and dust from the Vostok ice core over the last 400,000 years For current global climate change, see Global warming. ... The clathrate gun hypothesis states that as sea temperatures rise the sudden release of methane from methane clathrate compounds buried in the seabeds will cause a drastic alteration of the ocean enviornment and the atmosphere of earth, as recent analysis concerning the Permian extinction event indicates may have happened in...

Notes

^ The results were obtained by Dutch scientists from Utrecht University and the Royal NIOZ by analyzing the temperature-dependent composition of fatty substances called lipids in the cell membranes of marine archea. The presence of fossils of algae called dinoflagellates, a marker for sub-tropical climates, confirmed the findings "North Pole's ancient past holds clues about future global warming". Using this technique, the researchers found that sea surface temperatures at the North Pole had soared to 23 degrees Celsius, or around 73 degrees Fahrenheit (see Sluijs et al., 2006).
^ ^a ^b Zachos, J.C.; Röhl, U., Schellenberg, S.A., Sluijs, A., Hodell, D.A., Kelly, D.C., Thomas, E., Nicolo, M., Raffi, I., Lourens, L.J., McCarren, H. & Kroon, D. (2005). "Rapid Acidification of the Ocean during the Paleocene-Eocene Thermal Maximum". Science 308 (5728): 1611-1615.
^ Kennett, J.P. & Stott, L.D. 1991. Abrupt deep-sea warming, palaeoceanographic changes and benthic extinctions at the end of the Palaeocene. Nature, 353: 225-229
^ Koch, P.L., Zachos, J.C. & Gingerich, P.D. 1992. Correlation between isotope records in marine and continental carbon reservoirs near the Palaeocene/Eocene boundary. Nature, 358: 319-322
^ Sluijs, A., Schouten, S., Pagani, M., Woltering, M., Brinkhuis, H., Sinninghe Damsté, J.S., Dickens, G.R., Huber, M., Reichart, G.-J., Stein, R., Matthiessen, J., Lourens, L.J., Pedentchouk, N., Backman, J., Moran, K. & the Expedition, S. 2006
^ Global Warming Potential of Methane: http://www.grida.no/climate/ipcc_tar/wg1/248.htm
^ Carried out at QUAD-Lab at RUC in Denmark, the study published in Science.
^ Lourens, L.J.; Sluijs, A., Kroon, D., Zachos, J.C., Thomas, E., Röhl, U., Bowles, J. & Raffi, I. (2005). "Astronomical pacing of late Palaeocene to early Eocene global warming events". Nature 435 (7045): 1083-1087.

Utrecht University (Universiteit Utrecht in Dutch) is a university in Utrecht, The Netherlands. ... Figure 1: Basic lipid structure. ... Phyla / Classes Phylum Crenarchaeota Phylum Euryarchaeota Halobacteria Methanobacteria Methanococci Methanopyri Archaeoglobi Thermoplasmata Thermococci Phylum Korarchaeota Phylum Nanoarchaeota The Archaea are a major group of prokaryotes. ... Classes Dinophyceae Noctiluciphyceae Syndiniophyceae The dinoflagellates are a large group of flagellate protists. ...

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