| Term: | Pack ice |
| Definition: |
Ice that is not attached to the shoreline and drifts in response to winds, currents, and other forces; some prefer the generic term drift ice, and reserve pack ice to mean drift ice that is closely packed. NSIDCCryosphere
Term used in a wide sense to include any area of sea ice, other than fast ice, no matter what form it takes or how it is disposed. The pack can be described as very open (with an ice concentration of 1/10 to 3/10), open (4/10 to 6/10, with many leads and polynyas and the floes generally not in contact with one another), close (7/10 to 8/10, composed of floes mostly in contact), very close (9/10 to less than 10/10), and compact (10/10, with no water visible, called consolidated pack ice if the floes are frozen together). ASPECT2012 Any ice at the sea surface except for fast ice and stamukhas regardless of its age, form, origin and other characteristics that has a possibility of movement (drift) under the action of winds, currents and tides. As a result of the dynamic processes (drift, divergence, convergance), the total and partial concentrations of drifting ice constantly change. Bushuyev Term used in a wide sense to include any area of sea ice, other than fast ice, no matter what form it takes or how it is disposed. WMOSeaIce A general term for the frozen state of the sea, and embracing a wide range of sea ice terms. Swisseduc All sea ice other than fast ice; thus, sea ice that is capable of substantial motion and deformation. (Also called ice pack.) AMSglossary Any area of sea, river or lake ice other than fast ice, no matter what form it takes or how it is disposed. Pack ice cover may be reported in tenths, or may be described as very open pack ice ( 1/10th to 3/10ths), open pack ice (4/10ths to 6/10ths), close pack ice (7/10ths to 9/10ths), and very close pack ice (practically 10/10ths, with little if any water visible). SPRI GCW |