Reconstructed River Water Temperature Dataset for Western Canada 1980-2018

Continuous water temperature data are important for understanding historical variability and trends of river thermal regime, as well as impacts of warming climate on aquatic ecosystem health. We describe a reconstructed daily water temperature dataset that supplements sparse historical observations for 55 river stations across western Canada. We employed the air2stream model for reconstructing water temperature dataset over the period 1980-2018, with air temperature and discharge data used as model inputs. The model was calibrated and validated by comparing with observed water temperature records, and the results indicate a reasonable statistical performance. We also present historical trends over the ice-free summer months from June to September using the reconstructed dataset, which indicate- significantly increasing water temperature trends for most stations. Besides trend analysis, the dataset could be used for various applications, such as calculation of heat fluxes, calibration/validation of process-based water temperature models, establishment of baseline condition for future climate projections, and assessment of impacts on ecosystems health and water quality. Dataset: https://catalogue.ec.gc.ca/geonetwork/srv/eng/catalog.search#/metadata/cc103402-ba59-43eb-820e-f319b6b5f9b4 (accessed on 25 February 2023) Dataset License: Open Government License-Canada: https://open.canada.ca/en/open-government-licence-canada (accessed on 25 February 2023)

Automated summary

Continuous water temperature data are crucial for understanding the historical variability and trends of river thermal regime and the impacts of warming climate on aquatic ecosystem health. This study presents a reconstructed daily water temperature dataset for 55 river stations in western Canada, supplementing sparse historical observations. The dataset, reconstructed using the air2stream model, shows reasonable statistical performance after calibration and validation. The historical trends derived from the dataset reveal significantly increasing water temperature trends during the ice-free summer months.