Climate refugia along Lake Superior’s shores: Disjunct arctic-alpine plants rely on cool shoreline temperatures but are unlikely to persist under climate warming

Climate refugia can serve as remnant habitat or stepping stones for species dispersal under climate warming. The largest freshwater lake by surface area, Lake Superior, USA and Canada, serves as a model system for understanding cooling-mediated local refugia, as its cool water temperatures and wave action have maintained shoreline habitats suitable for southern disjunct populations of arctic-alpine plants since deglaciation. Here we seek to explain spatial patterns and environmental drivers of arctic-alpine plant refugia along Lake Superior’s shores, and assess future risk to refugia under moderate (+3.5 °C) and warmest (+5.7 °C) climate warming scenarios. First, we examined how the interactive effects of summer surface water temperatures and wind affected onshore temperatures, resulting in areas of cooler refugia. Second, we developed an ecological niche model for presence of disjunct arctic-alpine refugia (pooling 1253 occurrences from 58 species) along the lake’s shoreline. Third, we..., , , # Title of Dataset: Climate refugia along Lake Superior’s shores: disjunct arctic-alpine plants rely on cool shoreline temperatures but are unlikely to persist under climate warming

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This dataset contains species occurrence records for 59 disjunct arctic-alpine species at Lake Superior. Hillman_species_occurrences_raw_data.csv contains location data for all occurrence records, as well as spatial data for elevation, bedrock type, depth of water within 10 km of shore, log of Euclidean distance from shore, and land surface temperature from MODIS/Terra satellite.
Data were used to build species distribution models for all species considered disjunct and 21 most common disjunct species.

Variable list:

Point - Number of points assigned to either a species occurrence or a randomly generated pseudoabsence point

pres_abs - Whether species is present or not (1 for present, 0 for absent)

Species - Species that is present at that location

Common name - Common name for species present at t...