Comparison of Passive Microwave Data with Shipborne Photographic Observations of Summer Sea Ice Concentration along an Arctic Cruise Path

Abstract

Arctic sea ice concentration (SIC) has been studied extensively using passive microwave (PM) remote sensing. This technology could be used to improve navigation along vessel cruise paths; however, investigations on this topic have been limited. In this study, shipborne photographic observation (P-OBS) of sea ice was conducted using oblique-oriented cameras during the Chinese National Arctic Research Expedition in the summer of 2016. SIC and the areal fractions of open water, melt ponds, and sea ice (Aw, Ap, and Ai, respectively) were determined along the cruise path. The distribution of SIC along the cruise path was U-shaped, and open water accounted for a large proportion of the path. The SIC derived from the commonly used PM algorithms was compared with the moving average (MA) P-OBS SIC, including Bootstrap and NASA Team (NT) algorithms based on Special Sensor Microwave Imager/Sounder (SSMIS) data; and ARTIST sea ice, Bootstrap, Sea Ice Climate Change Initiative, and NASA Team 2 (NT2) algorithms based on Advanced Microwave Scanning Radiometer 2 (AMSR2) data. P-OBS performed better than PM remote sensing at detecting low SIC (< 10%). Our results indicate that PM SIC overestimates MA P-OBS SIC at low SIC, but underestimates it when SIC exceeds a turnover point (TP). The presence of melt ponds affected the accuracy of the PM SIC; the PM SIC shifted from an overestimate to an underestimate with increasing Ap, compared with MA P-OBS SIC below the TP, while the underestimation increased above the TP. The PM algorithms were then ranked; SSMIS-NT and AMSR2-NT2 are the best and worst choices for Arctic navigation, respectively.

Automatic High-Accuracy Sea Ice Mapping in the Arctic Using MODIS Data

“…Sea ice monitoring will help us to better understand the impact of climate change on species' habitats. In addition, with the increasing frequency of maritime economic activities and traffic in the Arctic, the demand for sea ice information monitoring is also increasing rapidly [7][8][9][10][11]. The increasing rate of sea ice melting has put the navigation of the Arctic waterway on the agenda, and sea ice information with a high spatial and temporal resolution will help us to accurately judge sea routes.…”

Editorial for Special Issue: “Remote Sensing of Environmental Changes in Cold Regions”

“…For assessing the performance of satellite products and algorithms, SIC data sets were derived from ship-borne photographic observations acquired along cruise paths and compared with six passive microwave remote sensing products. The comparisons suggest that satellite products likely over/underestimate SIC under low/high SIC conditions mainly due to the presence of melt ponds; and the Special Sensor Microwave Imager Sounder (SSMIS) NASA Team algorithm has the overall best accuracy [2].…”