Thursday, March 2, 2017| 3:30-4:30 pm, 401 Akasofu Arctic shipping and security expert Lawson Brigham will discuss recent changes in Arctic sea ice, greater marine access, and potentially longer seasons of navigation. These changes in turn influence a broad array of information requirements for tactical and strategic ice navigation. These requirements are also linked to operational planning on seasonal to annual time frames to support Arctic marine transportation systems. All three categories of ice navigation requirements can overlap in sea ice spatial scales and remote sensing performances. A new system of polar ship classification, the Polar Classes (1-7) are based on WMO sea ice nomenclature and define the ice types where a Polar Class ship can safely operate. Recent research has coupled the new polar ship classes with GCM sea ice simulations to estimate the length of the navigation season for select ship classes, and in a sense, quantify the increasing Arctic marine access. Such approaches provide a potential tool for strategic planners who support seasonal operational planning and ship routing in the Canadian Arctic, along the Northern Sea Route and even for the Central Arctic Ocean. Continued sea ice modelling efforts, new remote sensors, and diverse field observations remain critical to addressing the challenges of effective and safe ice navigation in the 21st century maritime Arctic.