Attribution of observed streamflow changes in key British Columbia drainage basins

Date

2017

Authors

Najafi, Mohammad R.
Zwiers, Francis W.
Gillett, Nathan P.

Journal Title

Journal ISSN

Volume Title

Publisher

Geophysical Research Letters

Abstract

We study the observed decline in summer streamflow in four key river basins in British Columbia (BC), Canada, using a formal detection and attribution (D&A) analysis procedure. Reconstructed and simulated streamflow is generated using the semidistributed variable infiltration capacity hydrologic model, which is driven by 1/16° gridded observations and downscaled climate model data from the Coupled Model Intercomparison Project phase 5 (CMIP5), respectively. The internal variability of the regional hydrologic components using ~5100 years of streamflow was simulated using CMIP5 preindustrial control runs. Results show that the observed changes in summer streamflow are inconsistent with simulations representing the responses to natural forcing factors alone, while the response to anthropogenic and natural forcing factors combined is detected in these changes. A two‐signal D&A analysis indicates that the effects of anthropogenic (ANT) forcing factors are discernable from natural forcing in BC, albeit with large uncertainties.

Description

Keywords

UN SDG 13: Climate Action, #journal article, Pacific Climate Impacts Consortium (PCIC), Canadian Centre for Climate Modelling and Analysis (CCCma)

Citation

Najafi, M. R., Zwiers, F. W., & Gillett, N. P. (2017). Attribution of observed streamflow changes in key British Columbia drainage basins. Geophysical Research Letters, 44(21), 11012–11020. https://doi.org/10.1002/2017GL075016