The role of conceptual frameworks in hydrological research and development

Many important issues in hydrological science are of a conceptual nature rather than computational or experimental. Valuable insight into these issues can be gained by means of critical conceptualism and a knowledge synthesis (KS) framework. By focusing on conceptual processes and not just form manipulations, KS develops the rational means for integrating physical knowledge bases relevant to the natural system of interest in order to obtain a realistic representation of the system, provide a rigorous assessment of the uncertainty sources, generate meaningful predictions in space-time, and produce science-based decisions. A Parmenidean approach of KS combines epistemic ideals with random field theory, offers new perspectives, and introduces challenging theoretical and interpretive questions to hydrological investigations. KS generates multi-point probability distributions using knowledge integration and information principles, the choice of which depends on logical and physical features of the problem. Insight is gained in terms of the solution of a physical equation of pollutant distribution and the calculation of effective parameters for heterogeneous media by upscaling. K e y w o r d s B M E ; cri t ical c o n c e p t u a l i s m ; h y d r o l o g y ; k n o w l e d g e syn thes i s ; uncer ta in ly