Climate Change and the Tundra of Nunavik : Exposure, Sensitivity and Vulnerability

The changing climate affects species and ecosystems while also changing the ecosystem services that humans depend on for their survival and well-being. This is particularly important in the Arctic, where snow and ice structure the ecosystems and where people maintain close ties with the land and its resources.

From an ecological perspective, the challenge consists of extracting the desired resources from the land while maintaining the services which these northern ecosystems provide, in a context where they are being transformed under the influence of climate change. Interpreting and projecting long-term ecological trends requires an excellent understanding of the relationships between species at the ecosystem level and how these relationships change in response to climate.

Environmental monitoring is also essential for the planning and implementation of conservation and land use planning strategies that are adapted to climate change.

• Identify, at the integrated ecosystem level, vulnerabilities of the tundra to climate change

• Apply this knowledge to the territory of Nunavik in order to facilitate and orient a land preservation strategy that is adapted to climate change.

• Climate reconstruction for the chosen reference period (1981-2010) throughout the Nunavik tundra, and projections of potential future climate for three time horizons (2011-2040, 2041-2070, 2071-2100);

• Compilation of all biological, ecological and distribution data available for 183 species under consideration in the study area; Modelling of current and potential future distribution of each mammal and bird species;

• Automated reconstruction of current and potential future trophic networks (aggregation of all predator-prey relationships) in each of the 4,315 100-km2 cells of the study area, and quantification of potential changes to these trophic networks;

• Mapping of these changes using an index of ecosystem vulnerability to climate change.

This project provides the first portrait of the effects of climate change on the structure (species composition) and functioning (links between species) of the Nunavik tundra. The magnitude of climate change in this region will be substantial, and will be even greater in the north.

Significant spatial reorganization of many plant and animal species is therefore predicted to occur during this century. An increase in the number of species is predicted for the Nunavik tundra, which is transitioning towards more boreal conditions. Climate change will lead to extensive restructuring of trophic networks, which indicates that the ecosystems in this region are highly vulnerable.

The modelling shows that part of Nunavik’s tundra zone is heterogeneous, and that its eastern portion appears to be more ecologically vulnerable to climate change than its western portion (Figure 1).

Figure 1 : Climate change vulnerability index map for the tundra ecosystems of Nunavik under RCP 4.5 (left) and RCP 8.5 (right), on the 2071-2100 horizon.

A summary of the results obtained for the 2071-2100 horizon is available in the final project report along with three technical appendices. A website (see References section on the first page) provides access to detailed results for the three time horizons under study (2011-2040, 2041-2070, 2071-2100) and allows hundreds of high-resolution maps to be downloaded according to user needs.

Finally, databases that comply with global archiving standards, namely the Polar Data Catalogue for project metadata and Nordicana D for complete project data sets, are also available. These will allow other teams to build on this work to further pursue the research directions outlined by this project.

• Centre d’Études Nordiques (CEN)

• Centre de la Science de la Biodiversité du Québec (CSBQ)

• Université Laval

• Carleton University

• Environnement et Changement climatique Canada (ECCC)

• University of Alberta

• Université de Moncton

• Université Sherbrooke