Editing IPCC:AR6/SROCC/Chapter-3 (section)

==== 3.2.4.3 Transportation ====

<div id="section-3-2-4-3-transportation-block-1"></div>

The Arctic is reliant on marine transportation for the import of food, fuel and other goods. At the same time, the global appetite for maritime trade and commerce through the Arctic (including community re-supply, mining and resource development, tourism, fisheries, cargo, research, and military and icebreaking, etc.) is increasing as the region becomes more accessible because of reduced sea ice cover. There are four potential Arctic international trade routes: the Northwest Passage, the Northern Sea Route, the Arctic Bridge and the Transpolar Sea Route. All of these routes offer significant trade benefits because they provide substantial distance savings compared to traditional routes via the Suez or Panama Canals.

There is ''high confidence'' that shipping activity during the Arctic summer increased over the past two decades in regions for which there is information, concurrent with reductions in Arctic sea ice extent and the shift to predominantly seasonal ice cover (Pizzolato et al., 2014 <sup>[[#fn:r887|887]]</sup> ; Eguíluz et al., 2016 <sup>[[#fn:r888|888]]</sup> ; Pizzolato et al., 2016 <sup>[[#fn:r889|889]]</sup> ). Long term datasets over the pan-Arctic are incomplete, but the distance travelled by ships in Arctic Canada nearly tripled between 1990 and 2015 (from ~365,000 to ~920,000 km) (Dawson et al., 2018 <sup>[[#fn:r890|890]]</sup> ). Other non-environmental factors which influence Arctic shipping are natural resource development, regional trade, geopolitics, commodity prices, global economic and social trends, national priorities, tourism demand, ship building technologies and insurance costs (Lasserre and Pelletier, 2011 <sup>[[#fn:r891|891]]</sup> ; Têtu et al., 2015 <sup>[[#fn:r892|892]]</sup> ; Johnston et al., 2017 <sup>[[#fn:r893|893]]</sup> ). Current impacts associated with the observed increase in Arctic shipping include a higher rate of reported accidents per km travelled compared to southern waters (CCA, 2016), increases in vessel noise propagation (Halliday et al., 2017 <sup>[[#fn:r894|894]]</sup> ) and air pollution (Marelle et al., 2016 <sup>[[#fn:r895|895]]</sup> ). Disruptions to cultural and subsistence hunting activities from increased shipping (Huntington et al., 2015 <sup>[[#fn:r896|896]]</sup> ; Olsen et al., 2019 <sup>[[#fn:r897|897]]</sup> ) compound climate-related impacts to people (Sections 3.4.3.3.2, 3.4.3.3.3).

It is projected that shipping activity will continue to rise across the Arctic as northern routes become increasingly accessible (Stephenson et al., 2011 <sup>[[#fn:r898|898]]</sup> ; Stephenson et al., 2013 <sup>[[#fn:r899|899]]</sup> ; Barnhart et al., 2015 <sup>[[#fn:r900|900]]</sup> ; Melia et al., 2016 <sup>[[#fn:r901|901]]</sup> ), although mitigating economic and operational factors remain uncertain and could influence future traffic volume (Zhang et al., 2016 <sup>[[#fn:r902|902]]</sup> ). The Northern Sea Route is expected to be more viable than other routes because of infrastructure already in place (Milaković et al., 2018 <sup>[[#fn:r903|903]]</sup> ); favourable summer ice conditions in recent years have reduced transit times (Aksenov et al., 2017 <sup>[[#fn:r904|904]]</sup> ). In comparison, the Northwest Passage and Arctic Bridge presently have limited port and marine transportation infrastructure, incomplete soundings and hydrographic charting, challenging sea ice conditions and limited search and rescue capacity; these compound the risks from shipping activity (Stephenson et al., 2013 <sup>[[#fn:r905|905]]</sup> ; Johnston et al., 2017 <sup>[[#fn:r906|906]]</sup> ; Andrews et al., 2018 <sup>[[#fn:r907|907]]</sup> ).

Future shipping impacts will be regionally diverse considering the unique geographies, sea ice dynamics, infrastructure and service availability and regulatory regimes that exist across different Arctic nations. Considerations include socioeconomic and political implications related to safety (marine and local accidents), security (trafficking, terrorism and local issues), and environmental and cultural sustainability (invasive species, release of biocides, chemicals and other waste, marine mammal strikes, fuel spills, air and underwater noise pollution and impacts to subsistence hunting) (Arctic Council, 2015a <sup>[[#fn:r908|908]]</sup> ; Halliday et al., 2017 <sup>[[#fn:r909|909]]</sup> ; Hauser et al., 2018 <sup>[[#fn:r910|910]]</sup> ). Black carbon emissions from shipping activity within the Arctic are projected to increase (Arctic Council, 2017 <sup>[[#fn:r911|911]]</sup> ) and are more easily deposited at the surface in the region compared with emissions from lower latitudes (Sand et al., 2013 <sup>[[#fn:r912|912]]</sup> ). Commercial shipping mainly uses heavy fuel oil, with associated emissions of sulphur, nitrogen, metals, hydrocarbons, organic compounds, black carbon and fly ash to the atmosphere during combustion (Turner et al., 2017a <sup>[[#fn:r913|913]]</sup> ). Mitigation approaches include banning heavy fuel oil as already implemented in Antarctica and the waters around Svalbard, and the use of new technology like scrubbers.

The predominant shipborne activities in Antarctica are fishing, logistic support to land-based stations, and marine research vessels operating for both non-governmental and governmental sectors. Uncertainty in future Antarctic sea ice conditions (Section 3.2.2.1) pose challenges to considering potential impacts on these activities (Chown, 2017 <sup>[[#fn:r914|914]]</sup> ).

<span id="polar-ice-sheets-and-glaciers-changes-consequences-and-impacts"></span>