There are several difficulties in reconciling theory with observations. Milankovitch cycles - 100 ky problem. The 100,000 year problem is that the eccentricity variations have a significantly smaller impact on solar forcing than precession or obliquity and hence might be expected to produce the weakest effects. However, observations show that during the last 1 million years, the strongest climate signal is the 100,000 year cycle. In addition, despite the relatively large 100,000 year cycle, some hav ...

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Milankovitch cycles, Milankovitch cycles - Earth's movements, Milankovitch cycles - Orbital shape, Milankovitch cycles - Axial tilt, Milankovitch cycles - Axial orientation, Milankovitch cycles - Orbital inclination, Milankovitch cycles - Problems, Milankovitch cycles - 100 ky problem, Milankovitch cycles - 400 ky problem, Milankovitch cycles - Stage 5 problem, Milankovitch cycles - Effect exceeds cause, Milankovitch cycles - The unsplit peak problem, Milankovitch cycles - The transition problem, Milankovitch cycles - Present conditions, Milankovitch cycles - The future

Read more here: » Milankovitch cycles: Encyclopedia II - Milankovitch cycles - Problems

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Milankovitch cycles, Milankovitch cycles - Earth's movements, Milankovitch cycles - Orbital shape, Milankovitch cycles - Axial tilt, Milankovitch cycles - Axial orientation, Milankovitch cycles - Orbital inclination, Milankovitch cycles - Problems, Milankovitch cycles - 100 ky problem, Milankovitch cycles - 400 ky problem, Milankovitch cycles - Stage 5 problem, Milankovitch cycles - Effect exceeds cause, Milankovitch cycles - The unsplit peak problem, Milankovitch cycles - The transition problem, Milankovitch cycles - Present conditions, Milankovitch cycles - The future

Read more here: » Milankovitch cycles: Encyclopedia II - Milankovitch cycles - Earth's movements

The amount of solar radiation (insolation) in the Northern Hemisphere at 65°N seems to be related to occurrence of an ice age. Astronomical calculations show that 65°N summer insolation should increase gradually over the next 25,000 years, and that no declines in 65°N summer insolation sufficient to cause an ice age are expected in the next 50,000 - 100,000 years. As mentioned above, at present perihelion occurs during the Southern Hemisphere's summer, and aphelion during the southern winter. Thus the Southern Hemisphere seasons sh ...

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Milankovitch cycles, Milankovitch cycles - Earth's movements, Milankovitch cycles - Orbital shape, Milankovitch cycles - Axial tilt, Milankovitch cycles - Axial orientation, Milankovitch cycles - Orbital inclination, Milankovitch cycles - Problems, Milankovitch cycles - 100 ky problem, Milankovitch cycles - 400 ky problem, Milankovitch cycles - Stage 5 problem, Milankovitch cycles - Effect exceeds cause, Milankovitch cycles - The unsplit peak problem, Milankovitch cycles - The transition problem, Milankovitch cycles - Present conditions, Milankovitch cycles - The future

Read more here: » Milankovitch cycles: Encyclopedia II - Milankovitch cycles - Present conditions

Main article: Milankovitch cycles This climatic event was probably a result of predictable changes in the Earth's orbit (Milankovitch cycles) and a continuation of changes that caused the end of the last glacial period. The effect would have had maximum Northern Hemisphere heating 9000 years ago when axial tilt was 24° and nearest approach to the Sun (perihelion) was during boreal summer. The calculated Milankovitch forcing would have provided 10% more solar radiation (+1W/m²) to the Northern ...

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Holocene climatic optimum, Holocene climatic optimum - Global effects, Holocene climatic optimum - Milankovitch cycles, Holocene climatic optimum - Other changes

Read more here: » Holocene climatic optimum: Encyclopedia II - Holocene climatic optimum - Milankovitch cycles

The Holocene Climate Optimum warm event consisted of increases of up to 4 °C near the North Pole (in one study, winter warming of 3-9°C and summer of 2-6°C in northern central Siberia)[1]. Northwestern Europe experienced warming, while there was cooling in the south.[2] The average temperature change appears to have declined rapidly with latitude so that ...

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Holocene climatic optimum, Holocene climatic optimum - Global effects, Holocene climatic optimum - Milankovitch cycles, Holocene climatic optimum - Other changes

Read more here: » Holocene climatic optimum: Encyclopedia II - Holocene climatic optimum - Global effects

The cause of ice ages remains controversial for both the large-scale ice age periods and the smaller ebb and flow of glacial/interglacial periods within an ice age. The general consensus is that it is a combination of up to three different factors: atmospheric composition (particularly the fraction of CO2 and methane), changes in the Earth's orbit around the Sun known as Milankovitch cycles (and possibly the Sun's orbit around the g ...

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Ice age, Ice age - Origin of ice age theory, Ice age - Major ice ages, Ice age - Interglacials, Ice age - Causes of ice ages, Ice age - Recent glacial and interglacial phases, Ice age - Glaciation in North America, Ice age - Reference

Read more here: » Ice age: Encyclopedia II - Ice age - Causes of ice ages

The climate system varies both through natural, "internal" processes as well as in response to variations in external "forcing" from both human and non-human causes, including changes in the Earth's orbit around the Sun (Milankovitch cycles), solar activity, and volcanic emissions as well as greenhouse gases. (See Climate change for further discussion of these forcing processes.) Climatologists accept that the earth has warmed recently. The cause or cause ...

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Global warming, Global warming - Overview, Global warming - Warming of the Earth, Global warming - Causes of global warming, Global warming - Greenhouse gas emissions, Global warming - Alternative theories, Global warming - Climate models, Global warming - Issues, Global warming - Public controversy, Global warming - Effects, Global warming - Effects on ecosystems, Global warming - Destabilisation of ocean currents, Global warming - Environmental refugees, Global warming - Spread of disease, Global warming - Financial effects, Global warming - Possible beneficial effects, Global warming - Mitigating and adapting to global warming

Read more here: » Global warming: Encyclopedia II - Global warming - Causes of global warming

The climate system varies both through natural, "internal" processes as well as in response to variations in external "forcing" from both human and non-human causes, including changes in the Earth's orbit around the Sun (Milankovitch cycles), solar activity, and volcanic emissions as well as greenhouse gases. Climatologists accept that the earth has warmed recently but the cause or causes of this change is somewhat more controversial, especially outside the scientific community. Atmospheric scientists know that adding carbon dioxide ( ...

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Global warming, Global warming - Overview, Global warming - Warming of the Earth, Global warming - Causes of global warming, Global warming - Greenhouse gas emissions, Global warming - Alternative theories, Global warming - Climate models, Global warming - Issues, Global warming - Public controversy, Global warming - Effects, Global warming - Effects on ecosystems, Global warming - Destabilisation of ocean currents, Global warming - Environmental refugees, Global warming - Spread of disease, Global warming - Financial effects, Global warming - Possible beneficial effects, Global warming - Mitigating and adapting to global warming

Read more here: » Global warming: Encyclopedia II - Global warming - Causes of global warming

Main articles: attribution of recent climate change and scientific opinion on climate change The climate system varies both through natural, "internal" processes as well as in response to variations in external "forcing" from both human and non-human causes, including changes in the Earth's orbit around the Sun (Milankovitch cycles), solar activity, and volcanic emissions as well as greenhouse gases. Climatologists accept that the earth has warmed recently but the cause or causes of this change is somewhat more ...

See also:

Global warming, Global warming - Overview, Global warming - Warming of the Earth, Global warming - Causes of global warming, Global warming - Greenhouse gas emissions, Global warming - Alternative theories, Global warming - Climate models, Global warming - Issues, Global warming - Public controversy, Global warming - Effects, Global warming - Effects on ecosystems, Global warming - Impact on Glaciers, Global warming - Destabilisation of ocean currents, Global warming - Environmental refugees, Global warming - Spread of disease, Global warming - Financial effects, Global warming - Possible beneficial effects, Global warming - Mitigating and adapting to global warming

Read more here: » Global warming: Encyclopedia II - Global warming - Causes of global warming

The following sections discuss a variety of scientific papers and other sources in an attempt to trace the rise and fall of interest in this concept during the 1970s. Global cooling - Pre-1970's. At a conference on climate change held in Boulder, Colorado in 1965, evidence supporting Milankovitch cycles triggered speculation on how the calculated small changes in sunlight might somehow trigger ice ages. In 1966 Cesare Emiliani predicted that "a new glaciation will begin within a few thousand years." In 196 ...

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Global cooling, Global cooling - Introduction: general awareness and concern, Global cooling - Physical mechanisms, Global cooling - Aerosols, Global cooling - Orbital forcing, Global cooling - Concern in the Middle of the Twentieth Century, Global cooling - Pre-1970's, Global cooling - 1970s Awareness, Global cooling - 1970 SCEP report, Global cooling - 1971 Paper on Warming and Cooling Factors, Global cooling - 1974 and 1972 National Science Board, Global cooling - 1975 National Academy of Sciences report, Global cooling - 1975 Newsweek article, Global cooling - 1979 WMO conference, Global cooling - Some other climate cooling catastrophes, Global cooling - The present level of knowledge, Global cooling - Climate science has improved, Global cooling - Historical geophysical meaning

Read more here: » Global cooling: Encyclopedia II - Global cooling - Concern in the Middle of the Twentieth Century

The Pleistocene Epoch is part of the geologic timescale. The name of the pleistocene is derived from the Greek pleistos (most) and ceno (new). The Pleistocene follows the Pliocene epoch and is followed by the Holocene epoch. The Pleistocene is the third epoch of the Neogene period or 6th epoch of the Cenozoic era. The end of the Pleistocene corresponds with the end of the ...

Including:

Pleistocene - Pleistocene dating Pleistocene - Pleistocene paleogeography and climate
Pleistocene - Major events Pleistocene - Palaeocycles
Pleistocene - Pleistocene fauna Pleistocene - Pleistocene deposits

Read more here: » Pleistocene: Encyclopedia - Pleistocene

Global warming is an increase in the average temperature of the Earth's atmosphere and oceans. The term is also used for the scientific theory of anthropogenic global warming, which attributes much of the recent observed and projected global warming to a human-induced intensification of the greenhouse effect. On this theory, the increased volumes of carbon dioxide and other greenhouse gases released mainly by the burning of fossil fuels, and, to a lesser extent, land clearing and agriculture, are the primary sources of warming. ...

Including:

Global warming - Overview Global warming - Warming of the Earth Global warming - Causes of global warming
Global warming - Alternative theories
Global warming - Climate models Global warming - Issues Global warming - Public controversy Global warming - Effects
Global warming - Effects on ecosystems Global warming - Destabilisation of ocean currents Global warming - Environmental refugees Global warming - Spread of disease Global warming - Financial effects Global warming - Possible beneficial effects
Global warming - Mitigating and adapting to global warming

Read more here: » Global warming: Encyclopedia - Global warming

Precession refers to a change in the direction of the axis of a rotating object. In physics, there are two types of precession, torque-free and torque-induced, the latter being discussed here in more detail. Specifically, precession may refer to the precession that the Earth experiences or its effects on astronomical observation, or to the precession of orbital objects. Precession - Torque-free precession. Only solid objects can be in torque-free precession. For example, when a plate is thrown, the plate ma ...

Including:

Precession - Torque-free precession Precession - Torque-induced precession Precession - The physics of precession Precession - Precession of the equinoxes Precession - Precession of planetary orbits Precession - Notes

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A glacier is a large, long-lasting river of ice that is formed on land and moves in response to gravity. A glacier is formed by multi-year ice accretion in sloping terrain. Glacier ice is the largest reservoir of fresh water on Earth, and second only to the oceans as the largest reservoir of total water. Glaciers can be found on every continent except Australia. Geologic features associated with glaciers include end, lateral, ground and medial moraines that form from glacially transported rocks and debris; U-shaped valleys and ...

Including:

Glacier - Types of glaciers Glacier - Formation of glaciers Glacier - Anatomy of a glacier Glacier - Glacial motion
Glacier - Moraines Glacier - Drumlins
Glacier - Glacial erosion
Glacier - Glacial valleys Glacier - Arêtes and horns Glacier - Sheepback rock Glacier - Alluvial stratification Glacier - Deposits in contact with ice Glacier - Loess deposits
Glacier - Isostatic rebound Glacier - Ice ages
Glacier - Ice age divisions Glacier - Causes of ice ages Glacier - Plate tectonics

Read more here: » Glacier: Encyclopedia - Glacier

Earth, also known as Terra, and Tellus mostly in the 19th century, is the third-closest planet to the Sun. It is the largest of the solar system's terrestrial planets, and the only planetary body that modern science confirms as harboring life. Scientific evidence indicates that the planet formed around 4.57 billion (4.57×109) years ago, and shortly thereafter (4.533 billion years ago) acquired its single natural satellite, the Moon. Earth - Lexicography. Its astronomical symbol con ...

Including:

Earth - Lexicography Earth - Physical characteristics Earth - Earth in the solar system Earth - Geography Earth - Environment and Ecosystem
Earth - Climate Earth - Terrain Earth - Natural resources Earth - Land use Earth - Natural and environmental hazards Earth - Human geography
Earth - Descriptions of Earth

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A cycle (Latin "cyclus," from Greek "kuklos" meaning circle) is anything round, in the physical sense (e.g. a bicycle) or in a temporal sense (e.g. the cycle of the seasons). Cyclic or cyclical are the adjective forms. Pages about cycles include: Cycle studies for interdisciplinary cycle research. See also Foundation for the Study of Cycles and list of cycles Cycle - Sports. Hitting for the cycle in Baseball The Paris-Roubaix Cycle Race. Including:

Cycle - Sports Cycle - Arts Cycle - History Cycle - Culture Cycle - Science
Cycle - Biology Cycle - Chemistry Cycle - Physics Cycle - Geology Cycle - Meteorology Cycle - Engineering Cycle - Mathematics Cycle - Computer science Cycle - Military science Cycle - Political science
Cycle - Business
Cycle - Finance Cycle - Telecommunication
Cycle - Crime

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Precession refers to a change in the direction of the axis of a rotating object. In physics, there are two types of precession, torque-free and torque-induced, the latter being discussed here in more detail. Specifically, precession may refer to the precession that the Earth experiences or its effects on astronomical observation, or to the precession of orbital objects. Precession - Torque-free precession. Only solid objects can be in torque-free precession. For example, when a plate is thrown, the plate ma ...

Including:

Precession - Torque-free precession Precession - Torque-induced precession Precession - The physics of precession Precession - Precession of the equinoxes
Precession - A changing north star
Precession - Precession of planetary orbits Precession - Notes

Read more here: » Precession: Encyclopedia - Precession

A cycle (Latin "cyclus," from Greek "kuklos" meaning circle) is anything round, in the physical sense (e.g. a bicycle) or in a temporal sense (e.g. the cycle of the seasons). Cyclic or cyclical are the adjective forms. Pages about cycles include: Cycle studies for interdisciplinary cycle research. See also Foundation for the Study of Cycles and list of cycles Cycle - Sports. Hitting for the cycle in Baseball The Paris-Roubaix Cycle Race. Including:

Cycle - Sports Cycle - Arts Cycle - History Cycle - Culture Cycle - Science
Cycle - Astronomy Cycle - Biology Cycle - Chemistry Cycle - Physics Cycle - Geology Cycle - Meteorology Cycle - Engineering Cycle - Mathematics Cycle - Computer science Cycle - Military science Cycle - Political science
Cycle - Business
Cycle - Finance Cycle - Telecommunication
Cycle - Crime

Read more here: » Cycle: Encyclopedia - Cycle

Mars has an axial tilt of 25.2°, quite close to the value of 23.45° for Earth, and thus Mars has seasons of spring, summer, autumn, winter as Earth does (if the axial tilt was 0° there would be no seasons). As on Earth, the southern and northern hemispheres have summer and winter at opposing times. However, the orbit of Mars has significantly greater eccentricity than that of Earth. Therefore the seasons are of unequal length, much more so than on Earth: In practical terms, this means that summers and winters have different ...

Including:

Astronomy on Mars - Seasons Astronomy on Mars - The color of the sky Astronomy on Mars - Astronomical phenomena
Astronomy on Mars - Earth and Moon Astronomy on Mars - Phobos and Deimos Astronomy on Mars - Meteors and meteor showers Astronomy on Mars - Auroras Astronomy on Mars - Celestial poles and ecliptic Astronomy on Mars - Long-term variations

Read more here: » Astronomy on Mars: Encyclopedia - Astronomy on Mars

The Pleistocene Epoch is part of the geologic timescale. The name of the pleistocene is derived from the Greek pleistos (most) and ceno (new). The Pleistocene follows the Pliocene epoch and is followed by the Holocene epoch. The Pleistocene is the third epoch of the Neogene period or 6th epoch of the Cenozoic era. The end of the Pleistocene corresponds with the end of the ...

Including:

Pleistocene - Pleistocene dating Pleistocene - Pleistocene paleogeography and climate
Pleistocene - Glacial features Pleistocene - Major events Pleistocene - Palaeocycles
Pleistocene - Pleistocene fauna Pleistocene - Pleistocene deposits

Read more here: » Pleistocene: Encyclopedia - Pleistocene