Risk management applied to human-induced radiological problems requires proper knowledge of what the situation would be without human interference. In cases where enhanced levels of natural radioactivity are present, this is far from simple, due to the existence of comparatively high and variable natural background levels. More knowledge on the spatial and temporal variety of natural radiation can help to decrease the uncertainty in the assessment of radiation doses from human activities. To obtain quantitative descriptions of the natural processes one needs accurate data showing a high resolution in time and space. This paper first shows that data obtained from the Dutch National Radioactivity Monitoring network, although developed for nuclear emergency management, meets these requirements. Next, some early, but interesting, results from a current comprehensive study are reported. Parameter values are given which describe the influence of air pressure, airborne radioactivity and rainfall on ambient dose rate. From the analysis of data distributions of ambient dose rate, information is obtained on the probability of elevated recordings occurring in a certain time period; this information can be used to select warning levels for nuclear alarm systems. Data analysis of airborne radioactivity shows that concentrations of 222Rn progeny are highly dependent on wind speed and direction. Results obtained for low wind speeds can be used to examine radon characteristics of the local environment while other results yield (aggregated) information about more remote areas.