Effective science communication in the face of water crises: a community perspective on challenges and best practice in HELPING

Addressing global water crises demands effective communication across diverse audiences, especially in initiatives such as the scientific decade HELPING by the International Association of Hydrological Sciences (IAHS). This study synthesizes insights from the hydrological community, gathered through interviews, workshops and a digital survey. We identify key challenges and best practices across three inter-related domains of communication: science–society interactions, policy–science interfaces and transdisciplinary research communication. Effective science–society interaction depends on community trust-building, transparent communication of uncertainty and inclusive engagement strategies. Strong policy–science interfaces benefit from bridging institutions and dedicated knowledge brokers. Transdisciplinary work improves when disciplinary siloing is reduced through common language and co-production. We summarize our findings in the FUSS framework, which promotes messages that are few, unambiguous, short and well-structured. We argue that advancing hydrological science in the face of water crises requires moving beyond one-way communication towards more dialogic, inclusive and context-sensitive approaches.