Alaska landfast sea ice: Links with bathymetry and atmospheric circulation

摘要: [1] Using Radarsat Synthetic Aperture Radar (SAR) imagery of northern Alaska and northwestern Canada, we calculated a mean climatology the annual landfast ice cycle for period 1996–2004. We also present monthly minimum, mean, maximum extents throughout study area. These data reveal where when is most stable which sections coast are susceptible to midseason breakout events. Stabilization strongly related advance seaward edge (SLIE) into waters around 18 m deep. Isobaths near this depth good approximation extent. Comparison with work from 1970s suggests reduced presence in region Arctic, due later formation earlier breakup. This will likely lead an increase coastal erosion may have profound effects upon subsistence activities, intimately linked timing marine mammal migration patterns. Interannually, correlates incursion pack waters, suggesting that date recent years be increasingly northward location perennial sea edge. The breakup well onset thawing air temperatures. Analysis regional shows multidecadal trend toward thaw onset, observed change dates part longer-term trend.