Editing Ice (section)

=== In the oceans ===
{{main|Sea ice}}
Ice that is found at sea may be in the form of [[drift ice]] floating in the water, [[fast ice]] fixed to a shoreline or [[anchor ice]] if attached to the seafloor.<ref>{{cite report |date=2014 |title=WMO Sea-ice Nomenclature |url=https://library.wmo.int/records/item/41953-wmo-sea-ice-nomenclature |publisher=Secretariat of the World Meteorological Organization }}</ref> Ice which [[Ice calving|calves]] (breaks off) from an [[ice shelf]] or a coastal glacier may become an iceberg.<ref>{{cite journal | last1 = Benn | first1 = D. | last2 = Warren | first2 = C. | last3 = Mottram | first3 = R. | year = 2007 | title = Calving processes and the dynamics of calving glaciers | url = http://stuff.mit.edu/~heimbach/papers_glaciology/earthscirev_benn_etal_2007_calving.pdf | journal = Earth-Science Reviews | volume = 82 | issue = 3–4| pages = 143–179 | doi=10.1016/j.earscirev.2007.02.002| bibcode = 2007ESRv...82..143B }}</ref> The aftermath of calving events produces a loose mixture of snow and ice known as [[Ice mélange]].<ref>{{Cite journal|last=Robel|first=Alexander A.|date=2017-03-01|title=Thinning sea ice weakens buttressing force of iceberg mélange and promotes calving|journal=Nature Communications|language=en|volume=8|pages=14596|doi=10.1038/ncomms14596|pmid=28248285|pmc=5339875|bibcode=2017NatCo...814596R |issn=2041-1723}}</ref> 

Sea ice forms in several stages. At first, small, millimeter-scale crystals accumulate on the water surface in what is known as [[frazil ice]]. As they become somewhat larger and more consistent in shape and cover, the water surface begins to look "oily" from above, so this stage is called [[grease ice]].<ref>{{Cite book |last1=Smedsrud |first1=Lars H. |last2=Skogseth |first2=Ragnheid |title=Field Measurements of Arctic Grease Ice Properties and Processes |publisher=Cold Regions Science and Technology 44 |year=2006 |pages=171–183 }}</ref> Then, ice continues to clump together, and solidify into flat cohesive pieces known as [[ice floe]]s. Ice floes are the basic building blocks of sea ice cover, and their horizontal size (defined as half of their [[diameter]]) varies dramatically, with the smallest measured in centimeters and the largest in hundreds of kilometers.<ref>{{cite journal |last1=Roach |first1=Lettie A. |last2=Horvat |first2=Christopher |last3=Dean |first3=Samuel M. |last4=Bitz |first4=Cecilia M. |title=An Emergent Sea Ice Floe Size Distribution in a Global Coupled Ocean-Sea Ice Model |journal= Journal of Geophysical Research: Oceans|date=6 May 2018 |volume=123 |issue=6 |pages=4322–4337 |doi=10.1029/2017JC013692 |bibcode=2018JGRC..123.4322R }}</ref> An area which is over 70% ice on its surface is said to be covered by pack ice.<ref>{{cite book|author1=Qin Zhang|author2=Roger Skjetne|title=Sea Ice Image Processing with MATLAB|url=https://books.google.com/books?id=DuJLDwAAQBAJ&pg=PP43|date=13 February 2018|publisher=CRC|isbn=978-1-351-06918-2|page=43}}</ref> 

Fully formed sea ice can be forced together by currents and winds to form [[Pressure ridge (ice)|pressure ridges]] up to {{convert|12|m}} tall.<ref>{{Cite journal |last1=Leppäranta |first1=Matti |last2=Hakala |first2=Risto |date=25 April 1991 |title=The structure and strength of first-year ice ridges in the Baltic Sea |journal=Cold Regions Science and Technology |volume=20 |issue=3 |pages=295–311 |doi=10.1016/0165-232X(92)90036-T }}</ref> On the other hand, active wave activity can reduce sea ice to small, regularly shaped pieces, known as [[pancake ice]].<ref>{{Cite journal|last=Squire|first=Vernon A.|date=2020|title=Ocean Wave Interactions with Sea Ice: A Reappraisal |journal=Annual Review of Fluid Mechanics |volume=52 |issue=1 |pages=37–60 |bibcode=2020AnRFM..52...37S |doi=10.1146/annurev-fluid-010719-060301|s2cid=198458049 |issn=0066-4189 |doi-access=free}}</ref> Sometimes, wind and wave activity "polishes" sea ice to perfectly spherical pieces known as [[ice eggs]].<ref>{{Cite news |date=2019-11-07 |title='Ice eggs' cover Finland beach in rare weather event |language=en-GB |work=BBC News |url=https://www.bbc.com/news/world-europe-50338447 |access-date=2022-04-22}}</ref><ref>{{Cite web |last=geographyrealm |date=2019-11-14 |title=How Ice Balls Form |url=https://www.geographyrealm.com/how-ice-balls-form/ |access-date=2022-04-23 |website=Geography Realm |language=en-US}}</ref>

<gallery mode="packed" heights="150px">
File:GreaseIce2.jpg|Grease ice in the [[Bering Sea]]
File:Greenland East Coast 7.jpg|Loose drift ice on the east coast of Greenland
File:Jää on kulmunud pallideks (Looduse veidrused). 05.jpg|Ice eggs (diameter 5–10 cm) on Stroomi Beach, Tallinn, Estonia
File:IceNomenclature-2LightPack.jpg|Ice floes in Antarctica, 1919
File:Ridge MOSAiC.jpg|A first-year sea ice ridge in the Central Arctic, photographed by the [[MOSAiC Expedition|MOSAiC expedition]] on July 4, 2020
File:A_Mélange_of_Ice_-_NASA_Earth_Observatory.jpg|Ice mélange on Greenland's western coast, 2012
File:Anchor ice under sea ice.JPG|Anchor ice on the seafloor at [[McMurdo Sound]], Antarctica.
</gallery>