We present a novel framework, tailored to freshwater, that incorporates three dimensions of vulnerability; namely exposure to climate change, sensitivity to altered environmental conditions, and resilience potential. The conceptual framework for calculation of the exposure uses various indicators describing the potential future changes in the magnitude, frequency, duration, timing and variability of precipitation and temperature events. The sensitivity assessment is based on concepts such as threat, range-restricted and ecoregion-restricted criteria of freshwater Key Biodiversity Areas, the Alliance for Zero Extinction concept and the species traits approach. Our resilience approach considers resilience more broadly as a structural feature of the landscape, i.e., catchments, and not solely as a species’ trait. To account for the hydrological catchment connectivity we considered natural dispersal barriers and dams.
Within this first regional assessment of the climate change vulnerability of European freshwater our vulnerability framework has been applied at the pan-European scale to 1,685 freshwater species, including plants, fishes, molluscs, odonates, amphibians, crayfish and turtles. Several methodologies were used to combine these dimensions across a variety of future climate change models and scenarios. The resulting indices were overlaid to assess the vulnerability of European freshwater ecosystems at the catchment scale and identify priority catchments that facilitate the development of broad-scale climate change conservation management strategies.