Large‐scale river flow archives: importance, current status and future needs

Time-series for river gauging stations are core blue-skies and applied resources for understanding impacts of climate and anthropogenic on basin hydrology. River flow archives hold vital information evidence-based assessment of past hydrological variability, support hydrological modelling of future changes. River discharge an integration of basin input, storage and transfer processes to the point. It is important to set basin outlet data in regional to and long-term contexts: to better understand nested scales of ; to pinpoint locations and time periods most sensitive to climate human impacts; to make predictions for ungauged basins; to inform decision makers on water security issues, and where and to take measures to mitigate water hazards and stress, including and droughts (Dai et al. , 2009; Bonnell et al. , 2006; Feyen Haddeland et al. , 2006; Hannah et al. , 2005). Thus, there clear rationale for supporting large-scale (i. e. regional to continental to) river flow archives. Notable examples of such databases include held by the WMO Global Runoff Data Centre (GRDC) and the Flow Regimes from International Experimental and Network (FRIEND) European Water Archive (EWA). For large-scale river archives to be valuable research resources, they must be fit for. However, these databases are at risk due to a possible decline network coverage, associated time-series truncation, growing human on (near-) natural flows, and increasingly restricted access to -scale data. This commentary aims: (1) to demonstrate largescale flow datasets are crucial to advance hydrological science and operational issues; (2) to assess the current status of large-scale flow datasets; and (3) to propose ways forward to consolidate historical and secure future river flow data.