What historical landfast ice observations tell us about projected ice conditions in Arctic archipelagoes and marginal seas under anthropogenic forcing

摘要: Abstract. Arctic landfast ice extent and duration are examined from observations, assimilations, ocean reanalyses coupled models. From observations and assimilations, it is shown that in areas where conditions last more than 5 months the first-year typically grows to more 2 m is rarely less 1 m. The observed spatial distribution of ice closely matches assimilation products but so for ocean and coupled Although models generally struggle represent landfast ice necessary emulate import/export sea regions favourable conditions, some do exhibit both a realistic climatology realistic decline under an anthropogenic forcing scenario. In these simulations, projections show an extensive cover should remain at least year, well into end 21st century. This in stark contrast with simulations have unrealistic emulation of landfast conditions. simulations, slow packed conditions shrink markedly over same period. all with landfast lasts 5 months, end-of-winter thickness remains between 1 2 m, beyond second half It is concluded current generation climate models, projections of winter Canadian Archipelago Laptev Sea overly sensitive representation and that ongoing development parameterization will likely better constrain projections.