Ice - Wikipedia Jump to content Main menu Main menu move to sidebar hide Navigation Main page Contents Current events Random article About Wikipedia Contact us Contribute Help Learn to edit Community portal Recent changes Upload file Special pages Search Search Appearance Donate Create account Log in Personal tools Donate Create account Log in Contents move to sidebar hide (Top) 1 Physical properties Toggle Physical properties subsection 1.1 Phases 1.2 Friction properties 2 Natural formation Toggle Natural formation subsection 2.1 In the oceans 2.2 On land 2.3 On rivers and streams 2.4 On lakes 2.5 As precipitation 2.5.1 Snow and freezing rain 2.5.2 Hard forms 2.6 On surfaces 3 Ablation 4 Role in human activities Toggle Role in human activities subsection 4.1 Cooling 4.1.1 Harvesting 4.1.2 Artificial production 4.2 Land travel 4.3 Water-borne travel 4.4 Air travel 4.5 Recreation and sports 4.6 Other uses 4.6.1 As thermal ballast 4.6.2 As structural material 5 Impacts of climate change Toggle Impacts of climate change subsection 5.1 Historical 5.2 Predictions 6 Non-water 7 See also 8 References 9 Further reading 10 External links Toggle the table of contents Ice 155 languages Afrikaans Alemannisch አማርኛ Aragonés Ænglisc العربية ܐܪܡܝܐ مصرى অসমীয়া Asturianu Atikamekw Авар Aymar aru Azərbaycanca تۆرکجه Žemaitėška Bikol Central Bajau Sama Беларуская (тарашкевіца) Беларуская Betawi Български भोजपुरी বাংলা Bosanski Català 閩東語 / Mìng-dĕ̤ng-ngṳ̄ Cebuano ᏣᎳᎩ Tsetsêhestâhese کوردی Čeština Чӑвашла Cymraeg Dansk Deutsch Zazaki डोटेली Ελληνικά Emiliàn e rumagnòl Esperanto Español Eesti Euskara فارسی Suomi Na Vosa Vakaviti Français Frysk Gaeilge Gàidhlig Galego Avañe'ẽ Hausa 客家語 / Hak-kâ-ngî עברית हिन्दी Hrvatski Kreyòl ayisyen Magyar Հայերեն Interlingua Bahasa Indonesia Interlingue Iñupiatun Ido Íslenska Italiano 日本語 Jawa ქართული Taqbaylit Kumoring Қазақша ಕನ್ನಡ 한국어 Кыргызча Latina Limburgs Lombard Lingála Lietuvių Latviešu Мокшень Malagasy Māori Minangkabau Македонски മലയാളം Монгол ꯃꯤꯇꯩ ꯂꯣꯟ मराठी Bahasa Melayu မြန်မာဘာသာ Эрзянь Nāhuatl Nedersaksies Plattdüütsch नेपाली Nederlands Norsk nynorsk Norsk bokmål Nouormand Occitan ଓଡ଼ିଆ ਪੰਜਾਬੀ Deitsch Polski پنجابی Português Runa Simi Română Руски Русский Саха тыла Sicilianu Scots سنڌي Srpskohrvatski / српскохрватски සිංහල Simple English Slovenčina Slovenščina Soomaaliga Shqip Српски / srpski Sunda Svenska Kiswahili Ślůnski தமிழ் Tayal తెలుగు Тоҷикӣ ไทย Tagalog Türkçe Українська اردو Oʻzbekcha / ўзбекча Vèneto Vepsän kel’ Tiếng Việt West-Vlams Volapük Walon Winaray 吴语 ייִדיש Vahcuengh 文言 閩南語 / Bân-lâm-gí 粵語 中文 IsiZulu Edit links Article Talk English Read View source View history Tools Tools move to sidebar hide Actions Read View source View history General What links here Related changes Upload file Permanent link Page information Cite this page Get shortened URL Switch to legacy parser Print/export Download as PDF Printable version In other projects Abstract Wikipedia Wikimedia Commons Wikidata item Appearance move to sidebar hide From Wikipedia, the free encyclopedia Frozen water; the solid state of water This article is about water ice. For the broader concept of "ices" as used in the planetary sciences, see Volatile (astrogeology). For the American law enforcement agency, see United States Immigration and Customs Enforcement. For the acronym of the Internal Combustion Engine, see Internal combustion engine. For other uses, see Ice (disambiguation). –0.9168<ref name=Voitkovskii/> g/cm³"},"abbe_number":{"wt":""},"refractive_index":{"wt":"1.309"},"chemical formula":{"wt":"{{chem2|H2O}}"},"youngs_modulus":{"wt":"3400 to 37,500 [[Kilogram-force|kg-force]]/cm²<ref name=Voitkovskii>{{Citation\n |last = Voitkovskii\n |first = K. F.\n |title = Translation of: \"The mechanical properties of ice\" (\"Mekhanicheskie svoistva l'da\")\n |publisher = Academy of Sciences (USSR)\n |id={{DTIC|AD0662716}}\n}}</ref>"},"tensile_strength":{"wt":"5 to 18&nbsp;kg-force/cm²<ref name=Voitkovskii/>"},"elongation":{"wt":""},"compressive_strength":{"wt":"24 to 60&nbsp;kg-force/cm²<ref name=Voitkovskii/>"},"poissons_ratio":{"wt":"{{val|0.36|0.13}}<ref name=Voitkovskii/>"},"thermal_conductivity":{"wt":"0.0053(1 + 0.0015 ''θ'') cal/(cm s K), ''θ'' = temperature in °C<ref name=Voitkovskii/>"},"thermal_diffusivity":{"wt":""},"linear_expansion":{"wt":"{{val|5.5|e=-5}}<ref name=Voitkovskii/>"},"specific_heat":{"wt":"0.5057 − 0.001863 ''θ'' cal/(g K), ''θ'' = absolute value of temperature in °C<ref name=Voitkovskii/>"},"specific_heat_note":{"wt":""},"dielectric_constant":{"wt":"~95<ref>{{cite journal |doi=10.3189/S0022143000018840|title=Dielectric Properties of Ice and Snow–a Review |year=1965 |last1=Evans |first1=S. |journal=Journal of Glaciology |volume=5 |issue=42 |pages=773–792 |s2cid=227325642 |doi-access=free }}</ref>"},"footnotes":{"wt":"The properties of ice vary substantially with temperature, purity and other factors."}},"i":0}}]}'>Ice An ice block Physical properties Density (ρ) 0.9167[1]–0.9168[2] g/cm3 Refractive index (n) 1.309 Chemical properties Chemical formula H2O Mechanical properties Young's modulus (E) 3400 to 37,500 kg-force/cm2[2] Tensile strength (σt) 5 to 18 kg-force/cm2[2] Compressive strength (σc) 24 to 60 kg-force/cm2[2] Poisson's ratio (ν) 0.36±0.13[2] Thermal properties Thermal conductivity (k) 0.0053(1 + 0.0015 θ) cal/(cm s K), θ = temperature in °C[2] Linear thermal expansion coefficient (α) 5.5×10−5[2] Specific heat capacity (c) 0.5057 − 0.001863 θ cal/(g K), θ = absolute value of temperature in °C[2] Electrical properties Dielectric constant (εr) ~95[3] The properties of ice vary substantially with temperature, purity and other factors. Ice is water that is frozen into a solid state, typically forming at or below temperatures of 0 °C, 32 °F, or 273.15 K. It occurs naturally on Earth, on other planets, in Oort cloud objects, and as interstellar ice. As a naturally occurring crystalline inorganic solid with an ordered structure, ice is considered to be a mineral. Depending on the presence of impurities such as particles of soil or bubbles of air, it can appear transparent or a more or less opaque bluish-white color. Virtually all of the ice on Earth is of a hexagonal crystalline structure denoted as ice Ih (spoken as "ice one h"). Depending on temperature and pressure, at least nineteen phases (packing geometries) can exist. The most common phase transition to ice Ih occurs when liquid water is cooled below 0 °C (273.15 K, 32 °F) at standard atmospheric pressure. When water is cooled rapidly (quenching), up to three types of amorphous ice can form. Interstellar ice is overwhelmingly low-density amorphous ice (LDA), which likely makes LDA ice the most abundant type in the universe. When cooled slowly, correlated proton tunneling occurs below −253.15 °C (20 K, −423.67 °F) giving rise to macroscopic quantum phenomena. Ice is abundant on the Earth's surface, particularly in the polar regions and above the snow line, where it can aggregate from snow to form glaciers and ice sheets. As snowflakes and hail, ice is a common form of precipitation, and it may also be deposited directly by water vapor as frost. The transition from ice to water is melting and from ice directly to water vapor is sublimation. These processes play a key role in Earth's water cycle and climate. In the recent decades, ice volume on Earth has been decreasing due to climate change. The largest declines have occurred in the Arctic and in the mountains located outside of the polar regions. The loss of grounded ice (as opposed to floating sea ice) is the primary contributor to sea level rise. Humans have been using ice for various purposes for thousands of years. Some historic structures designed to hold ice to provide cooling are over 2,000 years old. Before the invention of refrigeration technology, the only way to safely store food without modifying it through preservatives was to use ice. Sufficiently solid surface ice makes waterways accessible to land transport during winter, and dedicated ice roads may be maintained. Ice also plays a major role in winter sports. Physical properties Further information: Water (properties) § Density of water and ice The three-dimensional crystal structure of H2O ice Ih (c) is composed of bases of H2O ice molecules (b) located on lattice points within the two-dimensional hexagonal space lattice (a).[4][5] Ice possesses a regular crystalline structure based on the molecule of water, which consists of a single oxygen atom covalently bonded to two hydrogen atoms, or H–O–H. However, many of the physical properties of water and ice are controlled by the formation of hydrogen bonds between adjacent oxygen and hydrogen atoms; while it is a weak bond, it is nonetheless critical in controlling the structure of both water and ice.[6] An unusual property of water is that its solid form—ice frozen at atmospheric pressure—is approximately 8.3% less dense than its liquid form; this is equivalent to a volumetric expansion of 9%. The density of ice is 0.9167[1]–0.9168[2] g/cm3 at 0 °C and standard atmospheric pressure (101,325 Pa), whereas water has a density of 0.9998[1]–0.999863[2] g/cm3 at the same temperature and pressure. Liquid water is densest, essentially 1.00 g/cm3, at 4 °C and begins to lose its density as the water molecules begin to form the hexagonal crystals of ice as the freezing point is reached. This is due to hydrogen bonding dominating the intermolecular forces, which results in a packing of molecules less compact in the solid. The density of ice increases slightly with decreasing temperature and has a value of 0.9340 g/cm3 at −180 °C (93 K).[7] When water freezes, it increases in volume (about 9% for fresh water).[8] The effect of expansion during freezing can be dramatic, and ice expansion is a basic cause of freeze-thaw weathering of rock in nature and damage to building foundations and roadways from frost heaving. It is also a common cause of the flooding of houses when water pipes burst due to the pressure of expanding water when it freezes.[9] Because ice is less dense than liquid water, it floats, and this prevents bottom-up freezing of the bodies of water. Instead, a sheltered environment for animal and plant life is formed beneath the floating ice, which protects the underside from short-term weather extremes such as wind chill. Sufficiently thin floating ice allows light to pass through, supporting the photosynthesis of bacterial and algal colonies.[10] When sea water freezes, the ice is riddled with brine-filled channels which sustain sympagic organisms such as bacteria, algae, copepods and annelids. In turn, they provide food for animals such as krill and specialized fish like the bald notothen, fed upon in turn by larger animals such as emperor penguins and minke whales.[11] Frozen waterfall in southeast New York When ice melts, it absorbs as much energy as it would take to heat an equivalent mass of water by 80 °C (176 °F).[12] During the melting process, the temperature remains constant at 0 °C (32 °F). While melting, any energy added breaks the hydrogen bonds between ice (water) molecules. Energy becomes available to increase the thermal energy (temperature) only after enough hydrogen bonds are broken that the ice can be considered liquid w…