2017年夏季北极中央航道海冰观测特征及海冰密集度遥感产品评估

The sea ice observations and assessment of satellite sea-ice concentration along the Central Arctic Passage in summer 2017

2017年夏季中国第八次北极科学考察期间,"雪龙"号极地考察船首次成功穿越北极中央航道,期间全程开展了海冰要素的人工观测。中央航道走航期间的平均海冰密集度和平均冰厚分别为0.64和1.5 m,海冰密集度时空变化大且以厚当年冰为主,高纬密集冰区的浮冰大小显著高于海冰边缘区。基于"雪龙"号的船基走航观测海冰密集度评估比较了国际上常用的5种常用的微波遥感反演海冰密集度产品,同走航目测海冰密集度点对点的比较,误差最大的为德国不来梅大学AMSR2基于Bootstrap算法的产品,平均误差和均方根误差分别为0.19和0.28;误差最小的为欧洲气象卫星应用组织基于AMSR2数据和OSHD和TUD两种不同算法的产品,平均误差分别为-0.02和0.01,均方根误差均为0.20。从日平均比较来看,AMSR2基于Bootstrap算法的误差最大,平均误差和均方根误差分别为0.15和0.20;AMSR2/OSI SAF(TUD)的误差最小,平均误差和均方根误差分别为0.0和0.11,OSI SAF产品更接近人工观测结果。

In summer 2017,for the first time,the Chinese R/V Xuelong successfully passed through the Central Arctic Passage(CAP)during the Chinese National Arctic Research Expedition(CHINARE 2017),the ship-based sea ice observations were carried out during this cruise.The results showed that the CAP was mainly occupied by thick first-year ice,the average sea ice concentration(SIC)and thickness along the CAP were 0.64 and 1.5 m,respectively;the ice floes in the central Arctic Ocean are significantly larger than the sea ice edge area.The 5 commonly used passive microwave satellite retrieved SIC datasets with a spatial resolution higher than 10 km were inter-compared and assessed using the ship-based SIC.The point to point comparison showed the AMSR2 SIC datasets(Bootstrap algorithm)released by University of Bremen had the largest bias and rms(root mean square)values with 0.19 and 0.28,while the AMSR2 SIC datasets(OSHD and TUD algorithm,respectively)released by Ocean and Sea Ice Satellite Application Facility(OSI SAF)were with the smallest bias of-0.02 and 0.01,and the rms values were both 0.20.The daily mean comparison showed that the AMSR2 SIC dataset(Bootstrap algorithm)released by University of Bremen and the AMSR2/OSI SAF(TUD)dataset had the largest(0.15 and 0.20)and smallest(0.0 and 0.11)mean bias and rms values,respectively.