Two sources of readily available and non‐overlapping space‐borne data on sea ice thickness over the Arctic (i.e., Ice, Cloud, and land Elevation Satellite [ICESat] and CryoSat‐2 [CS2]) were compared using overlapping thermal microwave radiometer data to examine their respective differences. As a bridge connecting these two data sets, data on the vertically polarized emissivity difference between 10.65 and 18.7 GHz derived from the Advanced Microwave Sounding Radiometer were related to ICESat and CS2 thickness values via regression. The results indicate that there are substantial and systematic differences in the ice thickness between these two data sets over the Arctic; ICESat ice thickness was systematically lower than that of CS2 by ~50 cm, compared to ice thickness from Operation IceBridge and upper looking sonar data. The CS2 thickness observed later than that of ICESat was found to be thicker, contradicting the thinning expected under global warming conditions. Correcting for the 50‐cm difference between ICESat or CS2 data revealed trends in ice volume that are consistent with the expected and modeled declines in the Pan‐Arctic Ice‐Ocean Modeling and Assimilation System data, further corroborating the 50 cm of relative bias observed between the two data sets.

中文翻译：

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北极地区ICESat和CryoSat-2海冰厚度之间的差异：分析冰量趋势的后果

利用重叠的热微波辐射计数据比较了北极的两个现成的和不重叠的，关于北极海冰厚度的星载数据（即冰，云和陆地高程卫星[ICESat]和CryoSat-2 [CS2]）。检查它们各自的差异。作为连接这两个数据集的桥梁，由高级微波探测辐射仪得出的有关10.65和18.7 GHz之间垂直极化发射率差异的数据通过回归与ICESat和CS2厚度值相关。结果表明，在北极这两个数据集之间的冰厚存在实质性和系统性差异。与来自IceBridge行动和上层声纳数据的冰厚度相比，ICESat的冰厚度有系统地比CS2低约50 cm。发现晚于ICESat观测到的CS2厚度更厚，这与在全球变暖条件下预期的变薄相矛盾。对ICESat或CS2数据之间的50 cm差异进行校正后，发现冰量趋势与Pan-Arctic Ice-Ocean建模和同化系统数据的预期下降和模型下降相一致，从而进一步证实了观测到的50 cm相对偏差这两个数据集。