Spatio-temporal propagation of North Atlantic Oscillation (NAO) rainfall deviations to streamflow in British catchments
Harry West, Nevil Quinn, Michael Horswell
Abstract
The North Atlantic Oscillation (NAO) teleconnection is often cited as the leading mode of climate variability in Great Britain. The NAO has been found to produce significant rainfall deviations that vary in space and time. This study sought to analyse the effect of the NAO at the catchment scale across a large number of catchments in Great Britain across a long study period (1900–2015). We first quantify the effect of the NAO on rainfall and streamflow at a monthly scale, revealing distinctive spatio-temporal patterns under positive and negative phases of the NAO. Through a comparison of correlation analyses we also explore whether catchment characteristics moderate the propagation of NAO–rainfall deviations to streamflow, and classify catchments based on their resilience and susceptibility to NAO–rainfall deviations. In summary, our analyses combined contribute to an improved understanding of the hydrometeorological impact of the NAO in British catchments.