Hydrology embraces a wide range of interests including scientific and engineering applications. Hydro-meteorology spans the interface between meteorology and hydrology, and professionals active in this subject may have trained in either or both disciplines. Hydro-geology addresses the science of water in the ground and has, as its name suggests, a close affinity with the geological sciences. Hydrologists undertake a wide range of activities in order to monitor, manage and protect the water environment. Many activities and studies would be impossible without hydrometric data measurement, collection and archiving.
Hydrologists frequently develop and use mathematical models to mimic the physical processes.
The study of drought and floods, including statistical studies of drought and flood risks. Modelling of complex water resource and water supply systems for planning and operation. Water quality and other environmental management studies. Environmental impacts on water and of engineering works to manage water. International Organisations - technology transfer, international cooperation.