2014 summer Arctic sea ice thickness and concentration from shipborne observations

ABSTRACT

A series of shipborne sea ice observations were performed during the Chinese National Arctic Research Expedition in the Pacific Arctic sector between 2 August 2014 and 1 September 2014. Undeformed sea ice thickness (SIT) as well as area fractions of open water, melt pond, and sea ice (A_w, A_p, and A_i) were monitored using downward-oriented and oblique-oriented cameras. The results show that SIT varied between 20 and 220 cm throughout the whole cruise, with the average and standard deviation equaling 104.9 and 29.1 cm, respectively. Mean A_w and A_i were 0.52 and 0.44 in the marginal ice zone, respectively, while mean A_w decreased to 0.23 and mean A_i increased to 0.73 in the pack ice zone. Limited variation between 0 and 0.32 in A_p was seen throughout the whole cruise. Shipborne sea ice concentration was then rectified and mapped across a large transect to validate estimates derived from the satellite sensors Special Sensor Microwave Imager/Sounder (SSMIS) (25 km) and AMSR2 (25 km). Overestimations were 9.5% and 9.9% for SSMIS and AMSR2 compared with measurements, respectively. The mean areal broadband surface albedo based on shipborne survey increased from 0.07 to 0.66 along the transect between 72°N and 81°N.

KEYWORDS:

• Arctic sea ice
• shipborne photography
• remote sensing
• surface albedo
• summer melt

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the National Key Research and Development Program of China [grant number 2016YFC1402702], [grant number 2015CB953901]; the National Natural Science Foundation of China [grant number 41676187], [grant number 41428603], [grant number 41376186], [grant number 41722605]; the High Technology of Ship Research Project of the Ministry of Industry and Information Technology [grant number [2013]417], [grant number [2013]412]; and Academy of Finland [grant number 283101].