Comment on ‘Detection of hydrologic trends and variability’ by Burn, D.H. and Hag Elnur, M.A., 2002. Journal of Hydrology 255, 107–122

We are in agreement with Burn and Hag Elnur [J. Hydrol. 255 (2002) 107] that streamflow trends and variability are related to meteorological factors. We expanded the analysis of streamflow variability by relating annual peaks and spring (April, May, June) discharges to ENSO (El Niño–Southern Oscillation) events. Since geophysical considerations suggest that western Canada is warmer and drier than usual during El Niño but cooler and wetter under La Nina influences, flow variability of many western Canadian rivers is found to be correlated with winter values of such indices as the Southern Oscillation Index (SOI), Multivariate ENSO Index (MEI) or PNA (Pacific/North American Index). The spatial pattern of the non-parametric Spearman's r2 (for streamflow vs SOI) indicates a general correspondence with the correlation pattern of SOI-precipitation reported by Shabbar et al. [J. Climate 10 (1997) 3016]. This reinforces the linkage between streamflow variability, precipitation and climatic forcing.