Observations of supercooled water and frazil ice formation in an Arctic coastal polynya from moorings and satellite imagery

• DOI: 10.3189/2015aog69a839
• Publication Date: 2015-03-19T11:57:01Z
• Authors: Masato Ito; Kay I. Ohshima; Yasushi Fukamachi; Daisuke Simizu; Katsushi Iwamoto; Yoshimasa Matsumura; Andrew R. Mahoney; Hajo Eicken
• Keywords: Mooring

Abstract Formation of supercooled water and frazil ice was studied in the Chukchi Sea coastal polynya off Barrow, Alaska, USA, winter 2009/10, using moored salinity/temperature sensors Ice Profiling Sonar (IPS) data along with satellite data. Oceanographic from two moorings revealed episodic events potential supercooling at 30–40m depth, including possibility situ supercooling, while open. We identified ice-like signals IPS down to 5–15 m associated large heat loss windy, turbulent conditions an active polynya. This likely represents first observation marine environment. On day maximum signal ice, spaceborne synthetic aperture radar shows streaks high backscatter within polynya, indicating formation just downwind mooring sites. In addition, longer-term that persisted for 1–3 weeks occurred twice despite absence activity These during periods dominated by northeastward current. A series polynyas had formed southwest sites prior these events. Thus, masses were advected polynyas.