两种准实时遥感海冰密集度产品在中国第五次北极考察期间的适用性评估

The assessment of the applicability of AMSR2 and SSMIS near real time satellite sea ice concentration during 5^(th) CHINARE arctic cruise

比较了AMSR2和SSMIS产品在2012年中国第五次北极考察期间的差异,并利用雪龙船在北极走航观测的海冰密集度资料初步评估了两种卫星产品在北极东北航道和高纬航道的适用性。结果表明:两种产品在海冰边缘区域反演的海冰密集度差异较大,且在高纬度区域AMSR2反演的密集度普遍大于SSMIS;两种产品对海冰外缘线的反演基本相同,说明两种算法对海冰和海水的区分基本一致;在去程低纬航线上分辨率较高的AMSR2数据的平均偏差为0.14±0.11,而分辨率较低的SSMIS数据为0.17±0.11;在回程高纬航线上AMSR2数据的平均偏差为0.11±0.10,而SSMIS数据为0.11±0.12。SSMIS数据在高值区明显的低估了海冰密集度值,说明其在高值区的反演上存在系统性偏差,AMSR2数据和走航观测数据更相符。SSMIS数据在高值区偏差大的原因可能与其反演算法对海冰表面出现的大量融池的辨别能力较差有关。

AMSR2 and SSMIS satellite sea ice concentration data was evaluated and compared, using the ship-based sea ice concentration observations during the 5 th CHINARE Northeast Passage cruise in Jul-Sep2012. Results show that, the two kinds of satellite data have large differences out of the 80° N circle. The distinction of sea ice edge were good for both two data and AMSR2 showed better fits with the ship-based observations. Average bias in the go-path for SSMIS and AMSR2 is 0.17±0.11 and 0.14±0.11 respectively, but in the return-path is 0.11 ± 0.12 and 0.11 ± 0.10 respectively. SSMIS underestimate sea ice concentration in the high value region, but AMSR2 match with ship-based observations well. The bias of SSMIS may be caused by the bad distinction of melting pools showed in the summer.