Global warming and other climatic changes are causing rapid and widespread changes to the landscape, vegetation, and water cycling. Cold regions, such as the interior of western Canada, are at the forefront of this change and are highly sensitive to further warming. Dramatic changes are occurring to landscapes and hydro-ecological systems. There is therefore an urgent need to understand the nature of the changes and to develop the improved modelling tools needed to manage uncertain futures. To this end, the Changing Cold Regions Network (CCRN; www.ccrnetwork.ca) aims to understand, diagnose, and predict interactions amongst the cryospheric, ecological, hydrological, and climatic components of the changing Earth system at multiple scales with a geographic focus on western Canada, including the Saskatchewan and Mackenzie River basins.

CCRN is a Canadian-led research programme led by a consortium of eight universities and four federal agencies, due to be completed in March 2018. It is therefore timely for a special issue to bring together papers that synthesize this research and address recent advances in understanding, diagnosis, and prediction of past and future changes in cold-region Earth systems either as part of the CCRN initiative or from other studies around the world. The development and use of numerical models to diagnose past change and predict future sensitivity and response under various climate and land-cover scenarios is a particular focus. Key questions of relevance include whether cold-region hydrological processes and their interactions have changed in response to climatic drivers, what the feedbacks and thresholds leading to cold-region Earth system changes are, and/or what factors impart hydrological resilience or sensitivity to change in cold regions.

The special issue is open to all submissions within its scope and welcomes related studies from cold-region environments around the world.