Abstract Seasonal sea ice – ice which freezes in late fall and melts completely the following summer – is a central feature in the ecology, geomorphology, and climatology of the eastern Bering Sea. In this region's coastal zones, sea ice becomes locked in a stationary position against coastlines and influences interactions among land, ocean, and atmospheric processes. A thorough understanding of how this stationary ice, known as landfast ice, affects unique biogeophysical processes in the eastern Bering Sea region is limited by a lack of data on its areal coverage and seasonal duration. Here, we present the most comprehensive landfast ice dataset created to date for the Alaska Bering Sea region, derived using satellite imagery dated 1996–2008. This study provides a baseline set of observations regarding the landfast ice regime by identifying patterns in spatial distribution and interannual change. Our results show that spatial distribution and interannual change vary by regional geography in the eastern Bering Sea. Landfast ice widths averaged approximately 4.2 km on Northern Section, 18.8 km on the Central Section coastlines, and 8.9 km on the Yukon-Kuskokwim Delta. Modal water depths at the landfast ice edge varied by the Northern Northern, Central, and Southern Section coastlines as well, with respective modal values of −13 m, −7 m, and − 8.5 m. We attribute these regional variations in width and water depth to differing conditions in near-shore bathymetry and coastal morphology. On an interannual basis, landfast ice formed 5 days later in the year, and broke up 4 days earlier on average in the eastern Bering Sea region from 1996 to 2008. Notably, ice-free conditions occurred 15 days later on the Central Section coastlines. The spatial distribution and interannual change of landfast ice is of importance to associated environmental changes in the eastern Bering Sea region, including accelerated coastal erosion, difficulties surrounding subsistence activities, diminishing wildlife habitat, and seasonal shifts in sediment transport into marine food webs from rivers.

中文翻译：

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白令海东部陆上冰的年度循环

摘要 季节性海冰——在深秋结冰并在次年夏季完全融化——是白令海东部生态、地貌和气候学的核心特征。在该地区的沿海地区，海冰被锁定在海岸线的固定位置，并影响陆地、海洋和大气过程之间的相互作用。由于缺乏关于其面积覆盖和季节性持续时间的数据，因此对这种被称为固陆冰的静止冰如何影响白令海东部地区独特的生物地球物理过程的透彻了解是有限的。在这里，我们展示了迄今为止为阿拉斯加白令海地区创建的最全面的陆上冰数据集，该数据集使用日期为 1996-2008 年的卫星图像得出。这项研究通过确定空间分布和年际变化的模式，提供了一组关于固陆冰区的基线观测。我们的研究结果表明，白令海东部的空间分布和年际变化因区域地理而异。Landfast 冰宽度在北段平均约为 4.2 公里，在中央段海岸线为 18.8 公里，在育空 - 库斯科维姆三角洲为 8.9 公里。固陆冰缘的模态水深也因北北部、中部和南部海岸线而异，其模态值分别为-13 m、-7 m 和- 8.5 m。我们将宽度和水深的这些区域变化归因于近岸水深测量和海岸形态的不同条件。在年际的基础上，固陆冰在这一年的 5 天后形成，1996 年至 2008 年，白令海东部地区平均提前 4 天解冻。值得注意的是，中段海岸线在 15 天后解冻。固陆冰的空间分布和年际变化对白令海东部地区的相关环境变化具有重要意义，包括海岸侵蚀加速、生存活动困难、野生动物栖息地减少以及沉积物从河流进入海洋食物网的季节性变化。