Other uncertainties: Invasive species, disease pathways

Models and projections of extreme weather events are lacking for coastal BC [74]. There is little available data on future extreme weather, storm surge, or sea level rise at the scale of the MaPP region. Existing estimates of future sea-level rise vary widely, and projections at a regional scale are either largely unavailable or even more variable.

Investment in this research area would allow decision makers to better plan and implement operational adaptive actions to improve the outcome of high wind events and storm surge impacts. Risk assessments for extreme weather and storm surge, especially as these impacts combine with sea level rise, will continue to be an important area of research in order to develop the appropriate information to maintain and build infrastructure along the coastal region.

Improved projections of sea level rise for Canada’s coastlines are in progress with Fisheries and Oceans Canada through the Regional Mean Sea-Level Rise Scenarios for the Canadian Coasts program, which will produce four regional sea level scenarios (from low to high) for the Atlantic, Pacific, and Arctic coasts [30]. These data will improve the ability of regions, communities, and sectors to manage infrastructure and development in a way that facilitates effective adaptation to the risks associated with sea level changes. Sea level rise projections [36] have been produced at decadal time periods through to 2100 and are included in this report (see Maps section), but are at a coarse scale and not at a fine scale for in-shore waters. Forthcoming marine connectivity analyses will help to identify communities that are highly dependent on marine infrastructure and would be very vulnerable to disruption [118].

There is ongoing work through Fisheries and Oceans Canada to develop a hind-castwave model for coastal BC waters (expected in 2 years), which will characterize storm surge patterns across the coast and fill data gaps in the northern coast where tide gauges are sparse (T. James, Natural Resources Canada, pers. comm. June 2017). The Canadian Geodetic Survey is also working to develop sea level rise projections for Canada’s coastal areas, but results are not yet available (T. James, Natural Resources Canada, pers. comm. June 2017).

The existing state of knowledge for ocean acidification is limited, and other than global datasets, there are currently no projections at the scale of the BC coast [63]. This is partly due to a lack of empirical data as model inputs. Sampling for alkalinity and dissolved organic carbon has occurred as a regular part of DFO surveys since 1992 and 1986 respectively, but the data has been fragmented and inconsistent [63]. Very little is known about the state of the nearshore waters. Ongoing efforts to model changes in ocean chemistry (nitrogen, carbon, and oxygen) will improve the overall understanding of coastal biochemical processes and nearshore acidification and hypoxia levels (K. Hunter, DFO, pers. comm. July 2017). In addition, further efforts to model changes and extremes in pH (Ianson and Monahan, in progress; [29]) will improve the understanding of projected changes in acidification and the associated impacts.

Statistical downscaling can be used to map coarse-scale global climate model outputs to finer scale (regional or local) detail, using the empirical relationship between observed climatology at the finer resolution, and coarse-scale model fields. Regional climate models can also produce local projections, which may better represent the local responses to climate change [116]. There is a lack of reliable downscaled projections or regional climate modeled data for most climate impacts in the marine environment of BC, and within the MaPP region. Much of the climate impacts work within BC is focused on terrestrial impacts (e.g. [117]; AdaptTree), rather than marine and coastal impacts, and as such is of more limited applicability to the marine and coastal focus of the MaPP region (T. Murdoch, PCIC, pers. comm. July 2017). Regional climate vulnerabilities are also unknown for most sectors within BC. Fisheries and Oceans Canada has an ongoing project to model climate change vulnerabilities in some fisheries (Karen Hunter, pers. comm. July 2017.), with early results expected within the next year. Other work is focused on modeling the impacts of warming river temperatures on juvenile salmon, with results forthcoming (K. Hunter, DFO, pers. comm. July 2017).

There is still a great deal of uncertainty in global climate change projections for coastal regions, and the associated vulnerabilities and risks [1,114,115]. Part of this uncertainty is due to lack of or limited access to reliable and continuous data sources. Specifically, large population centers and regions often draw most of the resources for long-term observations and other scientific monitoring necessary for adequate research. The other part of the uncertainty is the unpredictability of humans and their actions. New technologies are developed every day, but the diffusion and adoption of these technologies is often relatively slow. Understanding vulnerability and risk is more meaningful in smaller scales as characteristics of each community, their socio-economic structure, coastal context, environmental conditions, and institutional capacity contributes to their local vulnerability. Therefore, for uncertainties surrounding vulnerability and risk, the main knowledge gap lies with the lack of existing studies investigating the local and regional exposure and sensitivity to various climate change impacts.

This uncertainty in global climate projections and knowledge of local vulnerabilities and risk is further amplified by regional variations in local climate which interact with climate change, such as the El Niño – Southern Oscillation (ENSO) and Pacific Decadal Oscillation (PDO) [5,7,36]. Investments in monitoring and research will improve our understanding of climate change projections and impacts across the coastal region and at fine scales such as the MaPP sub-regions. Within BC, additional monitoring programs through the Hakai Institute and MEOPAR are in progress to monitor key climate change indicators including ocean acidification.