Data from: Stream thermalscape scenarios for British Columbia, Canada

Water temperature is a key feature of freshwater ecosystems but
comprehensive datasets are severely lacking, a limiting factor in research
and management of freshwater species and habitats. An existing statistical
stream temperature model developed for British Columbia (BC), Canada, was
refit to predict August mean stream temperatures, a common index of stream
thermal regime also used in thermalscapes developed for the western United
States (US). Thermalscapes of predicted August mean stream temperature
were produced for 680,000 km of stream network at approximately 400 m
intervals. Temperature predictions were averaged for 20-year periods from
1981–2100 to produce 86 scenarios: one for each historical period (i.e.,
1981–2000, 2001–2020), and 21 for each future period (i.e., six global
climate models and an ensemble average under three representative
concentration pathways). The final model performance was consistent with
other published regional-scale statistical models (R2 = 0.79, RMSE =
1.53°C, MAE = 1.18°C), performing well given the relative paucity of data,
large geographic extent, and range of climatic and physiographic
conditions. Model results suggested an average increase of August mean
stream temperature of 2.9 ± 1.0°C (RCP 4.5 ensemble mean ± SD) by end of
century, with significant heterogeneity in predicted temperatures and
warming rates across the province. Compared to stream temperature
predictions from the western US, the predictions for BC showed good
agreement at cross-border streams (Pearson’s r = 0.91), suggesting the
possible integration of both products for a thermalscape covering much of
western North America. These stream thermalscapes for BC address a major
data deficiency in freshwater ecosystems and have potential applications
to stream ecology, species distribution modelling, and evaluation of
climate change impacts.