First author, Christophe Cudennec, elaborates on his experience as Secretary General of IAHS, part of IUGG, member of ISC. The publication of this article in Hydrological Sciences Journal, the Journal of IAHS, demonstrates how a century-old scientific community offers a reflexive space, and how open science developments can benefit from engaging with and springboarding from the existing self-organized structures of the scientific community. Along with COVID-19-related  developments, we place the discussion of open science in the context of long-term and accelerating challenges of the Anthropocene, within which the hydrological entry point provides a key aspect and illustration based on the connecting and interfacing dimensions of water in nature and societies; the increasing role of water in security issues; and the diversity of water-related contexts and epistemologies across the world.

The article is open access and available at https://www.tandfonline.com/doi/full/10.1080/02626667.2022.2086462