The IAHS Decade on Predictions in Ungauged Basins (PUB) is an initiative of the International Association of Hydrological Sciences (IAHS) aimed at formulating and implementing appropriate science programs to engage and energize the scientific community, in a coordinated manner, towards achieving major advances in the capacity to make reliable predictions in ungauged basins. Now two years into the effort, PUB participants have defined a set of community science questions in the hydrological sciences with broad consensus and community buy-in.
Hydrologists worldwide have come to recognize the multi-disciplinary nature of their discipline and the need to establish efforts that will enable scientists from various sub-disciplines to integrate their work. This will surely lead to novel opportunities for scientific progress that would be unachievable with individual scientists working alone. In this context, the PUB initiative will undoubtedly lead to new predictive approaches based on a combination of current and new theories, and of existing and potentially new data sets, that are unimaginable at the present time. In particular, over the next 10 years PUB will lead to:
Development of a framework for, and implementation of, routine estimation of predictive uncertainty in all future hydrological predictions.
A new suite of models and methodologies that can be used with confidence for predictions in ungauged basins in different hydro-climatic zones.
A network of scientists and groups around the world, especially in developing countries, with the necessary scientific expertise and experience to solve emerging hydrological problems.
An array of measurement networks in selected basins around the world and associated databases of hydrological measurements to serve as a reference pool for new emerging questions.
This international initiative to foster and enable multi-disciplinary approaches to hydrology must be matched by national initiatives with similar objectives in individual countries or regions. The US-based Consortium of Universities for the Advancement of Hydrologic Science, Inc. (CUAHSI) is gaining momentum in this context. Links between CUAHSI and PUB are manifold; e.g., planned CUAHSI observatories as part of the larger international network of experimental drainage basins over a wide range of scales and hydro-climatic regimes.
In addition, there has been an immense effort within PUB to develop science questions that enable and stimulate scientific integrationan effort from which discussions within CUAHSI can benefit. The PUB initiative has created a momentum that can be used in this regard. New thinking and discussionsparticularly on a conceptual levelare required that allow us to rethink current assumptions and paradigms in the light of new requirements for hydrology.
Initiatives such as PUB and CUAHSI are leading to the threshold of exciting new opportunities that will help change the face of hydrology in this country and internationally to a truly integrative science, and to unify the hydrologic community in addressing common problems, in common basins, and using common tools. PUB is literally a grassroots-level movement, enabling open participation to everyone who is interested, and with a minimum of bureaucracy.