A multivariate-driven approach for disentangling the reduction in near-natural Iberian water resources post-1980

[摘要] Although the literature still debates how several anthropogenic and natural factors havecontributed to the recent streamflow decline in the Iberian Peninsula, acontinuing decrease in winter precipitation (WP) has been noticed in thisarea since the 1980s and has been associated with large-scale atmospheric drivers. Thiscontribution assesses the potential propagation of this WP deficit into water resourcevariability. For this purpose, the novel “NEar-Natural Water Inflows to REservoirs of Spain” (NENWIRES) dataset was created. The results highlightthat higher decreases in winter water inflows (WWIs) are alwaysrelated to WP reductions. However, while the decline in WP was strongly provoked by theenhancement of the North Atlantic Oscillation index (NAOi) during the study period, WWI reductions could not beessentially linked to the NAOi behaviour in several NENWIRES catchments. Instead,the intensification of drought conditions and forest extension promoted WWIdecreases over the target area and aided inunderstanding why WWI reductions were generally higher than WP decreases.In summary, most humid catchments registered a WWI decline that was mainly promotedby NAOi enhancement, whereas the extension of forest andevapotranspiration increases seem to explain WWI losses in semi-aridenvironments. This contribution sheds light on the recent debate regarding themagnitude and drivers of water resource decline over southern European regions.

[学科分类] 妇产科学