Synoptic Variability in Satellite Altimeter-Derived Radar Freeboard of Arctic Sea Ice
Synoptic Variability in Satellite Altimeter-Derived Radar Freeboard of Arctic Sea Ice
复制标题
卫星高度计雷达北极海冰干舷的天气变化
DOI：
10.1029/2022gl100696
复制
发表时间：
2023
影响因子：
5.2
通讯作者：
Nab C
中科院分区：
文献类型：
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作者：
Nab C
卫星对海冰干舷的观测是估算海冰厚度不可或缺的一部分。通常假设来自卫星Ku波段高度计的雷达脉冲穿透雪并从冰雪界面反射。因此，我们预计积雪和雷达干舷测量值之间存在负相关关系，因为增加的雪负荷会使浮冰下沉。在这项研究中，我们通过最近开发的最佳插值方案，从CryoSat-2和Sentinel-3高度计中生成每日分辨率的雷达干舷产品。我们发现雷达干舷异常和模拟积雪之间存在统计学显著（p< 0.05）正相关。这表明，在降雪后的一段时间内，雷达脉冲并不像通常假设的那样从冰雪界面散射。我们的研究结果提供了基于卫星的证据，证明冬季Ku波段雷达在冰雪界面上方的散射，违反了海冰厚度反演的一个关键假设。
Satellite observations of sea ice freeboard are integral to the estimation of sea ice thickness. It is commonly assumed that radar pulses from satellite‐mounted Ku‐band altimeters penetrate through the snow and reflect from the snow‐ice interface. We would therefore expect a negative correlation between snow accumulation and radar freeboard measurements, as increased snow loading weighs the ice floe down. In this study we produce daily resolution radar freeboard products from the CryoSat‐2 and Sentinel‐3 altimeters via a recently developed optimal interpolation scheme. We find statistically significant (p< 0.05) positive correlations between radar freeboard anomalies and modeled snow accumulation. This suggests that, in the period after snowfall, radar pulses are not scattering from the snow‐ice interface as commonly assumed. Our results offer satellite‐based evidence of winter Ku‐band radar scattering above the snow‐ice interface, violating a key assumption in sea ice thickness retrievals.