This ESSD special issue responds to an international need to improve the understanding and modelling of mountain snow and ice hydrological processes. Data sets contributed to the special issue should support and promote research on the effects of mountain snowpacks and glaciers on water supply as well as study of variations in energy and water exchange amongst different high-altitude regions. This initiative arises from a new GEWEX Hydroclimatology Panel cross-cut project – INARCH, the International Network for Alpine Research Catchment Hydrology (www.usask.ca/inarch ). The guest editors invite contributions of openly available detailed meteorological and hydrological observational archives from long-term research catchments at high temporal resolution (at least 5 years of continuous data with hourly sampling intervals for meteorological data, daily precipitation and streamflow, and regular snow and/or glacier mass balance surveys) in well-instrumented mountain regions around the world. Contributors and researchers will use this mountain hydrology data publication special issue for the benefit of global alpine hydrological research.