We present an Arctic ocean–sea ice reanalysis covering the period 2007–2016 based on the adjoint approach of the Estimating the Circulation and Climate of the Ocean (ECCO) consortium. The spatiotemporal variation of Arctic sea surface temperature (SST), sea ice concentration (SIC), and sea ice thickness (SIT) is substantially improved after the assimilation of ocean and sea ice observations. By assimilating additional World Ocean Atlas 2018 (WOA18) hydrographic data, the freshwater content of the Canadian Basin becomes closer to the observations and translates into changes of the ocean circulation and of transports through the Fram and Davis straits. This new reanalysis compares well with previous filter‐based (TOPAZ4) and nudging‐based (PIOMAS) reanalyses regarding SIC and SST. Benefiting from using the adjoint of the sea ice model, our reanalysis is superior to the ECCOv4r4 product considering sea ice parameters. However, the mean state and variability of the freshwater content and the transport properties of our reanalysis remain different from TOPAZ4 and ECCOv4r4, likely because of a lack of hydrographic observations.

中文翻译：

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使用伴生法对2007-2016年期间北冰洋-海冰再分析

我们基于估计海洋环流和气候（ECCO）财团的辅助方法，介绍了2007年至2016年期间的北极海冰再分析。对海和海冰观测资料进行同化后，北极海表温度（SST），海冰浓度（SIC）和海冰厚度（SIT）的时空变化得到了显着改善。通过吸收其他《 2018年世界海洋地图集》（WOA18）水文数据，加拿大盆地的淡水含量变得更接近观测值，并转化为海洋环流以及穿越弗拉姆海峡和戴维斯海峡的运输变化。这项新的重新分析与先前基于SIC和SST的基于过滤器（TOPAZ4）和基于裸结（PIOMAS）的重新分析相比非常好。受益于使用海冰模型的伴随，考虑到海冰参数，我们的再分析优于ECCOv4r4产品。但是，由于缺乏水文观测，淡水含量的平均状态和变异性以及我们重新分析的传输特性仍然与TOPAZ4和ECCOv4r4不同。