Climate change-driven reductions in sea ice have facilitated increased shipping traffic volumes across the Arctic. Here, we use climate model simulations to investigate changing navigability in the Canadian Arctic for major trade routes and coastal community resupply under 1, 2 and 4 °C of global warming above pre-industrial levels, on the basis of operational Polar Code regulations. Profound shifts in ship-accessible season length are projected across the Canadian Arctic, with the largest increases in the Beaufort region (100–200 d at 2 °C to 200–300 d at 4 °C). Projections along the Northwest Passage and Arctic Bridge trade routes indicate 100% navigation probability for part of the year, regardless of vessel type, above 2 °C of global warming. Along some major trade routes, substantial increases to season length are possible if operators assume additional risk and operate under marginally unsafe conditions. Local changes in accessibility for maritime resupply depend strongly on community location.

气候变化导致的海冰减少促进了北极航运量的增加。在这里，我们使用气候模型模拟来调查加拿大北极地区主要贸易路线的适航性变化以及在全球变暖高于工业化前水平 1、2 和 4°C 的情况下，根据可操作的极地代码规定，沿海社区再补给。预计整个加拿大北极地区的船舶可到达季节长度将发生重大变化，其中博福特地区的增幅最大（2°C 时为 100-200 天，4°C 时为 200-300 天）。西北航道和北极大桥贸易路线沿线的预测表明，在全球变暖 2°C 以上的情况下，无论船只类型如何，一年中部分时间的航行概率为 100%。沿着一些主要的贸易路线，如果运营商承担额外风险并在略微不安全的条件下运营，则季节长度可能会大幅增加。海上补给可及性的当地变化很大程度上取决于社区位置。