Risk Assessment of Ship Navigation in the Northwest Passage: Historical and Projection

Abstract

Shipping volumes in the Northwest Passage are likely to increase under climate change due to the distance advantage over traditional routes and the special strategic location of the Arctic. However, the harsh environment and poor channel conditions may pose a considerable risk to ship navigation. To ensure the safety of ships, understand the navigability of the route, and plan the sustainable use of the Northwest Passage, it is crucial to provide a quantitative risk assessment. Here, we present an analysis of several natural risks faced by ships in the Northwest Passage based on available datasets and use climate model simulations to project the navigability changes. The results showed that: (1) The sea-ice risk to ships in the Northwest Passage has been significantly reduced over the period 1979–2019, and the risk for Polar Class 6 (PC6) ships has decreased more rapidly than for general open-water (OW) ships. The difference in ice-breaking capacity further affects the seaworthy season, with the second seaworthy month being August for OW ships and October for PC6 ships, in addition to the commonly best September. (2) Low visibility is a more common form of adverse weather than strong wind for navigation in the Northwest Passage, mainly on the northern route, although pilotage conditions appear to be improving in September. (3) According to the comprehensive risk map, the distribution of risk is dominated by sea ice. The southern route of the Northwest Passage is superior to the northern route in terms of both sea ice and weather conditions, but there is a risk of shallow water. (4) For the northern route, which has greater transport potential, projections suggest that the sea-ice risk will be steadily lower than any extreme light ice year observed historically whether for the ship class OW or PC6 by 2050, with an increase of 50–80 navigable days, and the navigable period could be from June to January of the following year for PC6 ships by 2100. Our results provide valuable information for ships planning to pass through the Northwest Passage.

Progress and prospects of the research on the impact of Arctic climate and environmental changes on the tertiary sector

“…再次， 北极变化对运输条件的影响作用于路径 阻力和载具运力。前者意味着以降水增加、 极端天 气频发、 冰层消融为主的北极变化会改变多种运输 方式的路径状况(如道路的能见度 [33] 、 冬季道路的 稳定性 [2,8] 、 航道的浮冰和风浪 [2,34] 、 河流的水位和流 量 [31] )， 进而改变运输的可达性、 安全性和效率 [35] 。 注： 图中未展示包含多个细分行业的其他服务业。数据来源于 《The economy of the north 2020》 [7] ， 其中加拿大北 极地区为 2017 年数据， 其他地区为 2018 年数据。 图 1 北极各地区第三产业各行业的附加值占地区总产值的比例 可用速度 [25] ， 而降水增加和冻土退化导致地面软 化、 积水将限制全地形车的适用性 [36] ； 在水运中， 气 温升高会减少船只因低温产生的故障 [37] ， 而冰层消 融有助于船只加速 [27] 。 [46] ， 已成为众多北极社区收入和经济增长的主要 来源 [1,10] 。旅游业占北极各地区生产总值的比重一 般为 2%~8%， 在冰岛和阿拉斯加地区最高， 于 2017 年超过 8% [47] 。同时， 北极旅游业具有庞大的全球市 场。2017 年北极入境游客达 6637 万人次 [46] ， 中国在 近年来成为了北极旅游的重要客源地 [47] 。北极旅 游业依赖当地的景观和气候， 易受北极变化干扰。 了解北极变化对旅游业的影响对当地经济和游客 福祉至关重要。…”

“…目的地、 有更长的出行季节 [52][53] ， 并使游轮成为更普 遍的旅游出行方式 [8] 。同时， 为了追寻观赏物种， 栖 息地变化也间接推动出游目的地趋于偏远 [54] ； 积雪减 道新路线 [24,[27][28] ， 提高航道的通航率 [28][29] -延长北极航道的通航季节 [28][29][30]42] -延长春季、 秋季的河流通航期 [31] 改变道路的路况(如湿滑结冰、 低能见度、 堵塞封闭)和可达性 [27,33,43] 降低船只被冰围困的风险 [34] 、 低温故障 几率 [37] ， 提高航行速度 [27] -提升春季的河流运力(流量增加) [31] -致害影响 损耗道路质量 [17,38] 破坏道路 [39][40] 、 管道 [41] 、 机场 [2,23] 和港口 -限制冬季道路的通行路线 [25] 和覆盖 范围 [26][27]38] -缩短冬季道路的适宜期 [1,21,26] 缩短夏季具有高河流运力的时期 [31] ， 改变夏/秋季的河运安排 [32] 增加浮冰风险 [1,2,8] ， 降低冬季道路的 可靠性 [2,8] 引起恶劣海况(如风暴、 大浪) [2,8,44] 和航空 安全隐患 [45] 降低夏季的河流运力(水位和流量下降)， 形成低水位河运风险 [31] 降低雪地摩托 [25] 和全地形车的运输性能 …”

Mapping vessel traffic patterns in the ice-covered waters of the Pacific Arctic

“…Both sea ice concentration and thickness have been demonstrated to play a role in influencing the navigability of Arctic waters (Stephenson et al 2013;Melia et al 2016;Stocker et al 2020). Given the importance of ice thickness as a standard for determining the safety of navigation through methods such as the Polar Operational Limitations Assessment Risk Indexing System (POLARIS) Risk Index Outcome (RIO) method (Wang et al 2022), we chose a product that contained both thickness and concentration estimates. To this end, we used the CryoSat-2/SMOS Merged Product from the European Space Agency to calculate sea ice thickness and concentration in our region of interest (Ricker et al 2017).…”

Sea Ice Extraction in SAR Images via a Spatially Constrained Gamma Mixture Model

“…This directly determines the process and rate of energy and material exchange between the ocean and the atmosphere and thus significantly affects climate change. In maritime navigation, the melting of sea ice may lead to a connection between oceans, which will bring incalculable economic benefits, highlight the military and strategic significance of the polar region [3,4], and accelerate the competition for resource development. In addition, the freezing of the sea surface will become a marine disaster, causing serious economic losses such as the collapse and shut down of production on the oil platform and the trapping of fishing boats [5][6][7].…”