Hydrological models: a review

Hydrological modelling is carried out for understanding the Earth's environmental system and it improves decision-making in water resource planning, flood prediction, irrigation practices, groundwater development, etc. Different kind of hydrological parameters are implemented in the soft computing models, mathematical models and systematic model. These combined models perform complex hydrological models. It is simply classified as physical-based, conceptual, empirical and hybrid hydrological models and it releases the suitable models for the global or particular national. Every hydrological model is ad hoc with several hydrological parameters as input, but it provides the results as hydrological components, especially runoff. At this moment, the runoff parameter is used for understanding the hydrological model efficiency, which depends upon the model requirements. Moreover, runoff parameter is mandatory, and performs the model calibration and validation using monitored runoff to follow the model efficiency at the present scenario. In this paper, model classification is reviewed to understand the model requirement and efficiency over the watershed, from the limited sources of hydrological data with hydrological modelling chosen for the real-time world.