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Citation Radić, V., A. J. Cannon, B. Menounos, and N. Gi (2015), Future changes in autumn atmospheric river events in British Columbia, Canada, as projected by CMIP5 global climate models, J. Geophys. Res. Atmos., 120, 9279–9302, doi:10.1002/2015JD023279.
Organization PCIC
URL http://onlinelibrary.wiley.com/doi/10.1002/2015JD023279/full
Abstract/Description or Keywords Atmospheric rivers (ARs) often trigger extreme precipitation events in British Columbia (BC), Canada. Here we analyze how well the autumn AR events with the highest probability for extreme precipitation over BC, henceforth called AR-extreme events, are simulated in five Coupled Model Intercomparison Project Phase 5 (CMIP5) global climate models (GCMs) and how these AR-extreme events are projected to change by the end of the century. We examine the daily synoptic patterns of integrated water vapor transport (IVT) over the Pacific Ocean that favor the formation of AR-extreme events. Our analysis and comparison with AR-extreme events in four reanalysis products for the period 1979–2010 reveal that the GCMs more successfully resolve their seasonality and interannual variability than their frequencies and amount of precipitation brought to BC. For the CMIP5 scenario's Representative Concentration Pathway (RCP) 4.5 and RCP8.5, the frequency of AR-extreme events will increase for the period 2070–2100 with the largest increase in December. All models project an increase in total precipitation over BC, due to the increase in frequency and intensity of the AR-extreme events; however, the dominant factor is the increase in frequency, especially of those events with precipitation exceeding 20 mmd−1. The path of the ARs during the AR-extreme events is projected to move northward, bringing stronger IVT and more precipitation to the north coast of BC, while the south coast may become drier than at the present day. The shift in the ARs is driven by the northward shift in the Aleutian Low pressure system, especially in RCP8.5.
Information Type article
Regional Watershed Coast Region
Sub-watershed if known
Aquifer #
Project status complete
Contact Name Alex Cannon
Contact Email [email protected]