A hydrological network based on an instrument for automatic time-variable data acquisition

Time constant data acquisition usually allows only inexact data sampling, or sampling with a high volume of storage, depending on the time interval used. The method of time-variable data recording uses only the points of time with relevant information, thus increasing resolution and decreasing storage demands. It has been applied since 1979 both for rainfall and runoff gauges in the Pollau experimental basin and provides a completely automatic way of data acquisition by a microcomputer system. It is not only possible to use the continuous time series for numerical investigations both in time and space, but this sampling technique also allows the analysing of events and the use of their information as inputs for forecasting and other models. Regional networks can be established and used as sub-information for larger drainage basins. The information stored in a data base can be linked and provides large time series with high resolution by the method of time-variable data recording.