View source for Physics:Cold

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{{short description|State of low temperature}}
[[File:Antarctic iceberg, 2001 -2.jpg|thumb|right|300px|An [[Earth:Iceberg|iceberg]], which is commonly associated with cold]]
[[File:Diving signal cold.jpg|thumb|right|Signal "cold" – unofficial (except recommended by CMAS), it is nonetheless used by many schools of diving and propagated through diving websites as one of the more useful additional signals<ref>[http://www.dive-links.com/en/uwzeichen.php Scuba Diving – Hand Signals] {{webarchive|url=https://web.archive.org/web/20090414195610/http://www.dive-links.com/en/uwzeichen.php |date=14 April 2009 }}</ref>]]

[[File:Goose bumps.jpg|thumb|right|[[Medicine:Goose bumps|Goose bumps]], a common physiological response to cold, aiming to reduce the loss of body heat in a cold environment]]
[[File:AntarcticaDomeCSnow.jpg|thumb|right|A photograph of the snow surface at [[Place:Dome C|Dome C]] Station, Antarctica. A part of the notoriously cold Polar Plateau, it is representative of the majority of the continent's surface.]]
'''Cold''' is the presence of low [[Physics:Temperature|temperature]], especially in the atmosphere. In common usage, cold is often a [[Philosophy:Subjectivity|subjective perception]]. A lower bound to temperature is [[Physics:Absolute zero|absolute zero]], defined as 0.00{{nbsp}}K on the [[Kelvin]] scale, an absolute [[Physics:Thermodynamic temperature|thermodynamic temperature]] scale. This corresponds to {{convert|0|K|C|2|disp=out}} on the Celsius scale, {{convert|0|K|F|2|disp=out}} on the Fahrenheit scale, and {{convert|0|K|R|2|disp=out}} on the [[Physics:Rankine scale|Rankine scale]].

Since temperature relates to the [[Physics:Thermal energy|thermal energy]] held by an object or a sample of matter, which is the [[Physics:Kinetic energy|kinetic energy]] of the random motion of the particle constituents of matter, an object will have less thermal energy when it is colder and more when it is hotter. If it were possible to cool a system to absolute zero, all motion of the particles in a sample of matter would cease and they would be at complete rest in the [[Physics:Classical physics|classical]] sense. The object could be described as having zero thermal energy. Microscopically in the description of [[Physics:Quantum mechanics|quantum mechanics]], however, matter still has [[Physics:Zero-point energy|zero-point energy]] even at absolute zero, because of the [[Physics:Uncertainty principle|uncertainty principle]].

==Cooling==
{{Main|Physics:Refrigeration}}

Cooling refers to the process of becoming cold, or lowering in [[Physics:Temperature|temperature]]. This could be accomplished by removing heat from a system, or exposing the system to an environment with a lower temperature.

[[Physics:Coolant|Coolant]]s are [[Physics:Fluid|fluid]]s used to cool objects, prevent freezing and prevent erosion in machines.<ref>{{cite web|title=An Introduction to Coolant Technology|url=http://www.coolantexperts.com/coolant_overview/|website=coolantexperts.com|access-date=15 February 2016|url-status=live|archive-url=https://web.archive.org/web/20160223043806/http://www.coolantexperts.com/coolant_overview|archive-date=23 February 2016}}</ref>

[[Physics:Air cooling|Air cooling]] is the process of cooling an object by exposing it to air. This will only work if the air is at a lower temperature than the object, and the process can be enhanced by increasing the [[Surface area|surface area]], increasing the coolant flow rate, or decreasing the [[Physics:Mass|mass]] of the object.<ref>{{cite web|title=Air Cooling|url=https://www.techopedia.com/definition/2143/air-cooling|website=techopedia.com|access-date=16 February 2016|url-status=live|archive-url=https://web.archive.org/web/20160302104201/https://www.techopedia.com/definition/2143/air-cooling|archive-date=2 March 2016}}</ref>{{better source needed|date=September 2018}}

Another common method of cooling is exposing an object to [[Earth:Ice|ice]], [[Chemistry:Dry ice|dry ice]], or [[Chemistry:Liquid nitrogen|liquid nitrogen]]. This works by conduction; the heat is transferred from the relatively warm object to the relatively cold coolant.<ref>{{cite web|title=When you add energy to an object and the object warms, what exactly is happening inside the object?|url=http://www.atmo.arizona.edu/students/courselinks/spring13/atmo170a1s1/online_course/week_4/lect11_temperature_conduction_convection_latent_heat.html|website=atmo.arizona.edu|access-date=16 February 2016|url-status=live|archive-url=https://web.archive.org/web/20150916012857/http://www.atmo.arizona.edu/students/courselinks/spring13/atmo170a1s1/online_course/week_4/lect11_temperature_conduction_convection_latent_heat.html|archive-date=16 September 2015}}</ref>

[[Physics:Laser cooling|Laser cooling]] and magnetic evaporative cooling are techniques used to reach very low temperatures.<ref>{{cite web|title=Laser Cooling|url=http://hyperphysics.phy-astr.gsu.edu/hbase/optmod/lascool.html|website=hyperphysics.phy-astr.gsu.edu|access-date=15 February 2016|url-status=live|archive-url=https://web.archive.org/web/20160131011327/http://hyperphysics.phy-astr.gsu.edu/hbase/optmod/lascool.html|archive-date=31 January 2016}}</ref><ref>{{cite web|title=The basic idea of the evaporative cooling is simple.|url=http://cold-atoms.physics.lsa.umich.edu/projects/bec/evaporation.html|website=cold-atoms.physics.lsa.umich.edu|access-date=15 February 2016|url-status=live|archive-url=https://web.archive.org/web/20151209171752/http://cold-atoms.physics.lsa.umich.edu/projects/bec/evaporation.html|archive-date=9 December 2015}}</ref>

==History==

===Early history===
In ancient times, ice was not adopted for food preservation but used to cool wine which the Romans had also done. According to Pliny, [[Biography:Nero|Emperor Nero]] invented the ice bucket to chill wines instead of adding it to wine to make it cold as it would dilute it.{{Sfn|Shachtman|2000|p=17}}

Some time around 1700 BC Zimri-Lim, king of [[History:Mari, Syria|Mari Kingdom]] in northwest Iraq had created an "icehouse" called ''bit shurpin'' at a location close to his capital city on the banks of the [[Place:Euphrates|Euphrates]]. In the 7th century BC the Chinese had used icehouses to preserve vegetables and fruits. During the Tang dynastic rule in China (618–907 AD) a document refers to the practice of using ice that was in vogue during the Eastern Chou Dynasty (770–256 BC) by 94 workmen employed for "Ice-Service" to freeze everything from wine to dead bodies.{{Sfn|Shachtman|2000|p=17}}

Shachtman says that in the 4th century AD, the brother of the Japanese emperor Nintoku gave him a gift of ice from a mountain. The Emperor was so happy with the gift that he named the first of June as the "Day of Ice" and ceremoniously gave blocks of ice to his officials.{{Sfn|Shachtman|2000|p=17}}

Even in ancient times, Shachtman says, in Egypt and India, night cooling by evaporation of water and heat radiation, and the ability of salts to lower the freezing temperature of water was practiced. The ancient people of Rome and Greece were aware that boiled water cooled quicker than the ordinary water; the reason for this is that with boiling of water [[Chemistry:Carbon dioxide|carbon dioxide]] and other gases, which are deterrents to cooling, are removed; but this fact was not known till the 17th century.{{Sfn|Shachtman|2000|p=17}}

===From the 17th century===

Shachtman says that King [[Biography:James VI and I|James VI and I]] supported the work of [[Biography:Cornelis Drebbel|Cornelis Drebbel]] as a magician to perform tricks such as producing thunder, lightning, lions, birds, trembling leaves and so forth. In 1620 he gave a demonstration in Westminster Abbey to the king and his courtiers on the power of cold.{{Sfn|Shachtman|2000|p=4}} On a summer day, Shachtman says, Drebbel had created a chill (lowered the temperature by several degrees) in the hall of the Abbey, which made the king shiver and run out of the hall with his entourage. This was an incredible spectacle, says Shachtman. Several years before, Giambattista della Porta had demonstrated at the Abbey "ice fantasy gardens, intricate ice sculptures" and also iced drinks for banquets in [[Place:Florence|Florence]]. The only reference to the artificial freezing created by Drebbel was by [[Biography:Francis Bacon|Francis Bacon]]. His demonstration was not taken seriously as it was considered one of his magic tricks, as there was no practical application then. Drebbel had not revealed his secrets.{{Sfn|Shachtman|2000|pp=8-9}}

Shachtman says that Lord Chancellor Bacon, an advocate of experimental science, had tried in ''Novum Organum'', published in the late 1620s, to explain the artificial freezing experiment at Westminster Abbey, though he was not present during the demonstration, as "[[Chemistry:Potassium nitrate|Nitre]] (or rather its spirit) is very cold, and hence nitre or salt when added to snow or ice intensifies the cold of the latter, the nitre by adding to its own cold, but the salt by supplying activity to the cold snow." This explanation on the cold inducing aspects of ''nitre'' and salt was tried then by many scientists.{{Sfn|Shachtman|2000|pp=12-13}}

Shachtman says it was the lack of scientific knowledge in physics and chemistry that had held back progress in the beneficial use of ice until a drastic change in religious opinions in the 17th century. The intellectual barrier was broken by Francis Bacon and [[Biography:Robert Boyle|Robert Boyle]] who followed him in this quest for knowledge of cold.{{Sfn|Shachtman|2000|pp=18-25}} Boyle did extensive experimentation during the 17th century in the discipline of cold, and his research on pressure and volume was the forerunner of research in the field of cold during the 19th century. He explained his approach as "Bacon's identification of heat and cold as the right and left hands of nature".{{Sfn|Shachtman|2000|pp=25-26}} Boyle also refuted some of the theories mooted by [[Biography:Aristotle|Aristotle]] on cold by experimenting on transmission of cold from one material to the other. He proved that water was not the only source of cold but gold, silver and crystal, which had no water content, could also change to severe cold condition.{{Sfn|Shachtman|2000|p=28}}

===19th century===
[[File:Léon Perrault, 1890 - Out in the Cold.jpg|thumb|upright|right|''Out In The Cold'', Léon Bazille Perrault]]
In the United States from about 1850 till end of 19th century export of ice was second only to cotton. The first ice box was developed by Thomas Moore, a farmer from Maryland in 1810 to carry butter in an oval shaped wooden tub. The tub was provided with a metal lining in its interior and surrounded by a packing of ice. A rabbit skin was used as insulation. Moore also developed an ice box for domestic use with the container built over a space of {{convert|6|cuft}} which was filled with ice. In 1825, ice harvesting by use of a horse drawn ice cutting device was invented by Nathaniel J. Wyeth. The cut blocks of uniform size ice was a cheap method of food preservation widely practiced in the United States. Also developed in 1855 was a steam powered device to haul 600 tons of ice per hour. More innovations ensued. Devices using compressed air as a refrigerants were invented.{{Sfn|Flynn|2004|p=23}}

===20th century===
[[Physics:Icebox|Icebox]]es were in widespread use from the mid-19th century to the 1930s, when the [[Physics:Refrigerator|refrigerator]] was introduced into the home. Most municipally consumed ice was harvested in winter from snow-packed areas or frozen lakes, stored in ice houses, and delivered domestically as iceboxes became more common.

In 1913, refrigerators for home use were invented. In 1923 Frigidaire introduced the first self-contained unit. The introduction of [[Chemistry:Freon|Freon]] in the 1920s expanded the refrigerator market during the 1930s.<ref>{{cite web|title=The Story of the Refrigerator|url=http://www.aham.org/consumer/ht/action/GetDocumentAction/id/1409|website=aham.org|publisher=Association of Home Appliance Manufacturers|access-date=16 February 2016|url-status=dead|archive-url=https://web.archive.org/web/20160305065925/http://www.aham.org/consumer/ht/action/getdocumentaction/id/1409|archive-date=5 March 2016}}</ref> Home freezers as separate compartments (larger than necessary just for ice cubes) were introduced in 1940. Frozen foods, previously a luxury item, became commonplace.

==Physiological effects==
Cold has numerous [[Biology:Physiology|physiological]] and [[Biology:Pathology|pathological]] effects on the [[Medicine:Human body|human body]], as well as on other organisms. Cold environments may promote certain [[Social:Psychology|psychological]] traits, as well as having direct effects on the ability to move. [[Biology:Shivering|Shivering]] is one of the first physiological responses to cold.<ref name="mayo hypothermia">{{cite web | author=Mayo Clinic staff | title=Hypothermia: Symptoms | url=http://www.mayoclinic.org/diseases-conditions/hypothermia/basics/symptoms/con-20020453 | publisher=Mayo Clinic | access-date=15 February 2016 | url-status=live | archive-url=https://web.archive.org/web/20160204225820/http://www.mayoclinic.org/diseases-conditions/hypothermia/basics/symptoms/con-20020453 | archive-date=4 February 2016 | df=dmy-all }}</ref> Even at low temperatures, the cold can massively disrupt blood circulation. Extracellular water freezes and tissue is destroyed. It affects fingers, toes, nose, ears and cheeks particularly often. They discolor, swell, blister, and bleed. Local frostbite leads to so-called [[Medicine:Chilblains|chilblains]] or even to the death of entire body parts. Only temporary cold reactions of the skin are without consequences. As blood vessels contract, they become cool and pale, with less oxygen getting into the tissue. Warmth stimulates blood circulation again and is painful but harmless. Comprehensive protection against the cold is particularly important for children and for sports. Extreme cold temperatures may lead to [[Medicine:Frostbite|frostbite]], [[Medicine:Sepsis|sepsis]], and [[Physics:Hypothermia|hypothermia]], which in turn may result in death.<ref name="amputate">{{cite web | url=http://www.buffalo.edu/ubreporter/stories.host.html/content/shared/university/news/ub-reporter-articles/stories/2016/02/prescription_4_warmth.detail.html | title=Shocked by frostbite amputations, med students take action | date=2 February 2016 | author=Ellen Goldbaum | work=UB Reporter | access-date=15 February 2016 | url-status=dead | archive-url=https://web.archive.org/web/20160304192115/http://www.buffalo.edu/ubreporter/stories.host.html/content/shared/university/news/ub-reporter-articles/stories/2016/02/prescription_4_warmth.detail.html | archive-date=4 March 2016 | df=dmy-all }}</ref><ref>[https://www.alpin.de/sicher-am-berg/medizin/3454/artikel_frostschutz.html This is how cold protection works in winter (German) - Alpin 01/2007]</ref>

===Common myths===
A common, but false, statement states that cold weather itself can induce the identically named [[Medicine:Common cold|common cold]].<ref>{{Cite news|url=https://www.nytimes.com/2003/03/04/science/you-ll-catch-your-death-an-old-wives-tale-well.html|title = 'You'll Catch Your Death!' an Old Wives' Tale? Well . ..|newspaper = The New York Times|date = 4 March 2003|last1 = Zuger|first1 = Abigail}}</ref> No scientific evidence of this has been found, although the disease, alongside [[Medicine:Influenza|influenza]] and others, does [[Biology:Flu season|increase in prevalence]] with colder weather.

==Notable cold locations and objects==
[[File:Boomerang_nebula.jpg|right|thumb|Boomerang Nebula]]
[[File:Triton_moon_mosaic_Voyager_2_(large).jpg|right|thumb|Neptune's moon Triton]]
* The [[Organization:National Institute of Standards and Technology|National Institute of Standards and Technology]] in Boulder, Colorado using a new technique, managed to chill a microscopic mechanical drum to 360 micro[[Kelvin|kelvin]]s, making it the coldest object on record. Theoretically, using this technique, an object could be cooled to absolute zero.<ref>{{cite journal|title=Sideband cooling beyond the quantum backaction limit with squeezed light|first1=Jeremy B.|last1=Clark|first2=Florent|last2=Lecocq|first3=Raymond W.|last3=Simmonds|first4=José|last4=Aumentado|first5=John D.|last5=Teufel|date=11 January 2017|journal=Nature|volume=541|issue=7636|pages=191–195|doi=10.1038/nature20604|pmid = 28079081|arxiv=1606.08795|bibcode=2017Natur.541..191C|s2cid=4443249}}</ref>
* The coldest known temperature ever achieved is a [[Physics:State of matter|state of matter]] called the [[Physics:Bose–Einstein condensate|Bose–Einstein condensate]] which was first theorized to exist by [[Biography:Satyendra Nath Bose|Satyendra Nath Bose]] in 1924 and first created by Eric Cornell, [[Biography:Carl Wieman|Carl Wieman]], and co-workers at [[Organization:JILA|JILA]] on 5 June 1995. They did this by cooling a dilute vapor consisting of approximately two thousand [[Chemistry:Rubidium|rubidium-87]] atoms to below 170 nK (one nK or nanokelvin is a billionth (10<sup>−9</sup>) of a [[Kelvin|kelvin]]) using a combination of [[Physics:Laser cooling|laser cooling]] (a technique that won its inventors [[Biography:Steven Chu|Steven Chu]], [[Biography:Claude Cohen-Tannoudji|Claude Cohen-Tannoudji]], and William D. Phillips the 1997 Nobel Prize in Physics) and magnetic evaporative cooling.<ref>{{cite web|url=https://www.nobelprize.org/nobel_prizes/physics/laureates/1997/|title=The Nobel Prize in Physics 1997|url-status=live|archive-url=https://web.archive.org/web/20150924141848/http://www.nobelprize.org/nobel_prizes/physics/laureates/1997/|archive-date=24 September 2015}}</ref>
* [[Astronomy:90377 Sedna|90377 Sedna]] is one of the coldest known objects within the [[Astronomy:Solar System|Solar System]]. Orbiting at an average distance of 84 billion miles, Sedna has an average surface temperature of -400°F (-240°C).<ref>{{Cite web |title=Mysterious Sedna {{!}} Science Mission Directorate |url=https://science.nasa.gov/science-news/science-at-nasa/2004/16mar_sedna/ |access-date=2023-02-28 |website=science.nasa.gov |archive-date=16 May 2017 |archive-url=https://web.archive.org/web/20170516234331/https://science.nasa.gov/science-news/science-at-nasa/2004/16mar_sedna |url-status=dead }}</ref>
* The lunar crater [[Astronomy:Hermite (crater)|Hermite]] was described after a 2009 survey by [[Organization:NASA|NASA]]'s [[Astronomy:Lunar Reconnaissance Orbiter|Lunar Reconnaissance Orbiter]] as the "coldest known place in the Solar System", with temperatures at 26 [[Kelvin|kelvin]]s (−413 °F, −247 °C).<ref>{{cite news |last=Amos |first=Jonathan |url=http://news.bbc.co.uk/1/hi/sci/tech/8416749.stm |title='Coldest place' found on the Moon |work=BBC |date=16 December 2009 |access-date=17 December 2009}}</ref> 
* The [[Astronomy:Boomerang Nebula|Boomerang Nebula]] is the coldest known natural location in the [[Astronomy:Universe|universe]], with a temperature that is estimated at 1&nbsp;[[Kelvin|K]] (−272.15&nbsp;°C, −457.87&nbsp;°F).<ref>{{cite web|url=http://www.jpl.nasa.gov/news/releases/97/coldspot.html|title=Boomerang Nebula boasts the coolest spot in the Universe|date=20 June 1997|publisher=NASA's Jet Propulsion Laboratory|access-date=8 July 2009|url-status=live|archive-url=https://web.archive.org/web/20090827115717/http://jpl.nasa.gov/news/releases/97/coldspot.html|archive-date=27 August 2009}}</ref>
* The Dwarf Planet [[Astronomy:Haumea|Haumea]] is one of the coldest known objects in our solar system. With a Temperature of -401 degrees [[Fahrenheit]] or -241 degrees [[Celsius]]<ref>{{cite web | url=https://solarsystem.nasa.gov/planets/dwarf-planets/haumea/by-the-numbers/ | title=By the Numbers &#124; Haumea }}</ref>
* The [[Engineering:Planck (spacecraft)|Planck]] spacecraft's instruments are kept at 0.1 [[Kelvin|K]] (−273.05&nbsp;°C, −459.49&nbsp;°F) via passive and active cooling.<ref name="space20090707">{{cite news |url=http://www.space.com/6930-coldest-object-space-unnatural.html |title=Coldest Known Object in Space Is Very Unnatural |publisher=Space.com |author=Staff |date=7 July 2009 |access-date=3 July 2013 |url-status=live |archive-url=https://web.archive.org/web/20130703233020/http://www.space.com/6930-coldest-object-space-unnatural.html |archive-date=3 July 2013}}</ref>
* Absent any other source of heat, the temperature of the Universe is roughly 2.725 [[Kelvin|kelvin]]s, due to the Cosmic microwave background radiation, a remnant of the [[Astronomy:Big Bang|Big Bang]].<ref>{{cite web | last = Hinshaw | first = Gary | date = 15 December 2005 | url = http://map.gsfc.nasa.gov/universe/bb_tests_cmb.html | title = Tests of the Big Bang: The CMB | publisher = NASA WMAP | access-date = 9 January 2007 | url-status = live | archive-url = https://web.archive.org/web/20080320052809/http://map.gsfc.nasa.gov/universe/bb_tests_cmb.html | archive-date = 20 March 2008 | df = dmy-all }}</ref>
* Neptune's moon [[Astronomy:Triton (moon)|Triton]] has a surface temperature of 38.15 K (−235&nbsp;°C, −391&nbsp;°F)<ref>{{cite web | url=http://voyager.jpl.nasa.gov/science/neptune_triton.html | title=Voyager the Interstellar Mission | work=NASA: Jet Propulsion Laboratory, California Institute of Technology | access-date=15 February 2016 | url-status=dead | archive-url=https://web.archive.org/web/20071220005501/http://voyager.jpl.nasa.gov/science/neptune_triton.html | archive-date=20 December 2007 | df=dmy-all }}</ref>
* [[Astronomy:Uranus|Uranus]] with a [[Astronomy:Black body|black-body]] temperature of 58.2 K (−215.0&nbsp;°C, −354.9&nbsp;°F).<ref>{{cite web|url=http://nssdc.gsfc.nasa.gov/planetary/factsheet/uranusfact.html|title=Uranus Fact Sheet|url-status=dead|archive-url=https://web.archive.org/web/20130621011402/http://nssdc.gsfc.nasa.gov/planetary/factsheet/uranusfact.html|archive-date=21 June 2013|access-date=2 August 2012}}</ref>
* [[Astronomy:Saturn|Saturn]] with a black-body temperature of 81.1 K (−192.0&nbsp;°C, −313.7&nbsp;°F).<ref>{{cite web|url=http://nssdc.gsfc.nasa.gov/planetary/factsheet/saturnfact.html|title=Saturn Fact Sheet|url-status=dead|archive-url=https://web.archive.org/web/20110818175309/http://nssdc.gsfc.nasa.gov/planetary/factsheet/saturnfact.html|archive-date=18 August 2011|access-date=2 August 2012}}</ref>
* [[Astronomy:Mercury (planet)|Mercury]], despite being close to the Sun, is actually cold during its night, with a temperature of about 93.15 K (−180&nbsp;°C, −290&nbsp;°F). Mercury is cold during its night because it has no [[Astronomy:Atmosphere|atmosphere]] to trap in [[Astronomy:Solar gain|heat]] from the Sun.<ref>{{cite web|url=http://solarsystem.nasa.gov/planets/mercury/indepth|title=Mercury: In Depth|publisher=[[Organization:NASA|NASA]]|access-date=15 February 2016|url-status=live|archive-url=https://web.archive.org/web/20160202084356/http://solarsystem.nasa.gov/planets/mercury/indepth|archive-date=2 February 2016}}</ref>
* [[Astronomy:Jupiter|Jupiter]] with a black-body temperature of 110.0 K (−163.2&nbsp;°C, −261.67&nbsp;°F).<ref>{{cite web|url=http://nssdc.gsfc.nasa.gov/planetary/factsheet/jupiterfact.html|title=Jupiter Fact Sheet|url-status=dead|archive-url=https://web.archive.org/web/20110413155109/http://nssdc.gsfc.nasa.gov/planetary/factsheet/jupiterfact.html|archive-date=13 April 2011|access-date=2 August 2012}}</ref>
* [[Astronomy:Mars|Mars]] with a black-body temperature of 210.1 K (−63.05&nbsp;°C, −81.49&nbsp;°F).<ref>{{cite web|url=http://nssdc.gsfc.nasa.gov/planetary/factsheet/marsfact.html|title=Mars Fact Sheet|url-status=live|archive-url=https://web.archive.org/web/20131123014931/http://nssdc.gsfc.nasa.gov/planetary/factsheet/marsfact.html|archive-date=23 November 2013}}</ref>
* The coldest continent on [[Astronomy:Earth|Earth]] is [[Earth:Antarctica|Antarctica]].<ref>{{cite web|url=http://earthobservatory.nasa.gov/IOTD/view.php?id=8070|title=Melting Ice in Antarctica : Image of the Day|date=25 September 2007|url-status=live|archive-url=https://web.archive.org/web/20090119213621/http://earthobservatory.nasa.gov/IOTD/view.php?id=8070|archive-date=19 January 2009}}</ref> The coldest place on Earth is the [[Earth:Antarctic Plateau|Antarctic Plateau]],<ref>{{cite news| url=https://www.independent.co.uk/news/science/polar-explorers-reach-coldest-place-on-earth-433074.html | work=The Independent | location=London | title=Polar explorers reach coldest place on Earth | first=Paul | last=Bignell | date=21 January 2007 | access-date=30 April 2010|archive-url=https://web.archive.org/web/20120108165347/http://www.independent.co.uk/news/science/polar-explorers-reach-coldest-place-on-earth-433074.html|archive-date=8 January 2012}}</ref> an area of Antarctica around the [[Earth:South Pole|South Pole]] that has an [[Altitude|altitude]] of around {{convert|3000|m}}. The lowest reliably measured temperature on Earth of 183.9 K (−89.2&nbsp;°C, −128.6&nbsp;°F) was recorded there at Vostok Station on 21 July 1983.<ref>{{cite journal | author=Budretsky, A.B. | title=New absolute minimum of air temperature | journal=Bulletin of the Soviet Antarctic Expedition | url=http://www.aari.aq/publication/abs_min/abs_min.html | issue=105 | year=1984 | location=Leningrad | publisher=Gidrometeoizdat | language=ru | url-status=live | archive-url=https://web.archive.org/web/20090227071811/http://www.aari.aq/publication/abs_min/abs_min.html | archive-date=27 February 2009 | df=dmy-all }}</ref> The [[Physics:Pole of Cold|Poles of Cold]] are the places in the Southern and [[Earth:Northern Hemisphere|Northern Hemisphere]]s where the lowest air temperatures have been recorded. (''See List of weather records'').<ref>{{cite journal |last1=Weidner |first1=George |last2=King |first2=John |last3=Box |first3=Jason E. |last4=Colwell |first4=Steve |last5=Jones |first5=Phil |last6=Lazzara |first6=Matthew |last7=Cappelen |first7=John |last8=Brunet |first8=Manola |last9=Cerveny |first9=Randall S. |title=WMO evaluation of northern hemispheric coldest temperature: −69.6 °C at Klinck, Greenland, 22 December 1991 |journal=Royal Meteorological Society |date=23 September 2020 }}</ref>
* The cold deserts of the [[Earth:North Pole|North Pole]], known as the tundra region, experiences an annual snow fall of a few inches and temperatures recorded are as low as 203.15 K (−70&nbsp;°C, −94&nbsp;°F). Only a few small plants survive in the generally frozen ground (thaws only for a short spell).{{Sfn|Lawrence|2012|p=16}}
* Cold deserts of the Himalayas are a feature of a rain-shadow zone created by the mountain peaks of the Himalaya range that runs from Pamir Knot extending to the southern border of the Tibetan plateau; however this mountain range is also the reason for the monsoon rain fall in the [[Earth:Indian subcontinent|Indian subcontinent]]. This zone is located in an elevation of about 3,000&nbsp;m, and covers Ladakh, Lahaul, Spiti and Pooh. In addition, there are inner valleys within the main Himalayas such as Chamoli, some areas of Kinnaur, Pithoragarh and northern Sikkim which are also categorized as cold deserts.{{Sfn|Negi|2002|p=9}}

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<gallery mode="packed">
File:Adelie_Penguins_on_iceberg.jpg|[[Earth:Antarctica|Antarctica]]
File:Tanglanglapass.jpg|Cold desert of the Himalayas in Ladakh
Image:Frozen_tree_-_3.JPG|Tree with hoarfrost
Image:Alphonse-Desjardins.jpg|Frozen Saint Lawrence River
Image:Sea ice terrain.jpg|Winter sea ice
Image:Ice Climbing.jpg|Ice climbing
</gallery>

==Mythology and culture==
* Niflheim was a realm of primordial ice and cold with nine frozen rivers in Norse Mythology.{{Sfn|Toole|2015|p=118}}
* The "Hell in Dante's Inferno" is stated as Cocytus a frozen lake where Virgil and Dante were deposited.{{Sfn|Fowlie|1981|p=198}}

==See also==
{{div col|colwidth=27em}}
* Technical, scientific
** {{annotated link|Physics:Chiller}}
** {{annotated link|Physics:Cryogenics}}
** {{annotated link|Physics:Cryosphere}}
** {{annotated link|Physics:Melting point|Freezing point}}
** {{annotated link|Physics:Negative temperature}}
** {{annotated link|Physics:Thermodynamic beta|Coldness}}
** {{annotated link|Physics:Ultracold atom}}
* Entertainment, myth
** {{annotated link|Engineering:Ice cream}}
* Meteorological:
** {{annotated link|Astronomy:Inversion (meteorology)|Atmospheric inversion}}
** {{annotated link|Physics:Cold front}}
** {{annotated link|Earth:Freezing rain}}
** {{annotated link|Earth:Frost}}
** {{annotated link|Earth:Hail}}
** {{annotated link|Physics:Snow}}
* Geographical and climatological:
** {{annotated link|Earth:Glacier}}
** {{annotated link|Earth:Ice cap}}
** {{annotated link|Earth:Ice cap climate}}
** {{annotated link|Earth:Ice sheet}}
{{div col end}}


==References==
{{Reflist|30em}}

'''Bibliography'''
* {{cite book|last=Flynn|first=Thomas|title=Cryogenics Engineering|edition=2nd|year=2004|publisher=CRC Press |isbn=0-8247-5367-4}}
* {{cite book|last=Fowlie|first=Wallace|title=A Reading of Dante's Inferno|date=15 May 1981 |publisher=University of Chicago Press |isbn=978-0-226-25888-1 |url=https://books.google.com/books?id=MLeDrZBn2ncC&pg=PA198}}
* {{cite book|last=Lawrence|first=Ellen|title=What Is Climate?|date=1 January 2012|publisher=Bearport Publishing |isbn=978-1-61772-401-5 |url=https://books.google.com/books?id=DoFyHtc_g9EC&pg=PA16}}
* {{cite book|last=Negi|first=S.S.|title=Cold Deserts of India|year=2002|publisher=Indus Publishing |isbn=978-81-7387-127-6 |url=https://books.google.com/books?id=54RgJ6FgMl0C}}
* {{cite book|last=Shachtman|first=Tom |title=Absolute Zero and the Conquest of Cold|date=12 December 2000 |publisher=Houghton Mifflin Harcourt|isbn=978-0-547-52595-2 |url=https://books.google.com/books?id=IJ91od-UYygC}}

==External links==
{{wikimedia|collapsible=true|wikt=cold|c=Category:Cold|d=Q270952|voy=no|species=no}}<!-- we can refine these parameters as the TAFI week progresses; please do NOT delete this box -->
* {{Cite book|title = Soldier's Handbook for Individual Operations and Survival in Cold-Weather Areas|url = https://books.google.com/books?id=yNayWeaAXEYC|publisher = Smashbooks|year = 1974}}
* {{Cite news|title = Tips for Surviving in Antarctica|url = https://www.nytimes.com/2008/03/28/nyregion/28teacherbox.html|newspaper = The New York Times|date = 28 March 2008|access-date = 15 February 2016|issn = 0362-4331|first = Tom|last = Wagner}}

[[Category:Cold| ]]
[[Category:Thermodynamics]]

{{Sourceattribution|Cold}}