Climatology of daily rainfall semi-variance in The Netherlands

Rain gauges can offer high quality rainfall measurements at their locations. Networks of rain gauges can offer better insight into the space-time variability of rainfall, but they tend to be too widely spaced for accurate estimates between points. While remote sensing systems, such as radars and networks of microwave links, can offer good insight in the spatial variability of rainfall they tend to have more problems in identifying the correct rain amounts at the ground. A way to estimate the variability of rainfall between gauge points is to interpolate between them using fitted variograms. If a dense rain gauge network is lacking it is difficult to estimate variograms accurately. In this paper a 30-year dataset of daily rain accumulations gathered at 29 automatic weather stations operated by KNMI (Royal Netherlands Meteorological Institute) and a one-year dataset of 10 gauges in a network with a radius of 5 km around CESAR (Cabauw Experimental Site for Atmospheric Research) are employed to estimate variograms. Fitted variogram parameters are shown to vary according to season, following simple cosine functions. Semi-variances at short ranges during winter and spring tend to be underestimated, but semi-variances during summer and autumn are well predicted

Preliminary Study on the Feasibility of Performing Quantitative Precipitation Estimation Using X-band Radar

IRCTR has built an experimental X-band Doppler po-larimetric weather radar system aimed at obtaining high temporal and spatial resolution measurements of precipitation, with particular interest in light rain and drizzle. In this paper a first analysis of the feasibility of obtaining accurate quantitative precipitation estimation from the radar data performed using a high density network of rain gauges is presented

A free account or not? Its effect upon information yield in strategic interviews with suspects

Asking suspects for a free account (FA) at the start of an interview is considered good practice in a growing number of police organisations, whereas in others it still is not commonplace. This study explored whether interviews with or without such an invitation yielded more information from guilty suspects. Students in safety and security committed a mock crime and were then interviewed using a strategy of gradual disclosure of evidence, in the experimental condition preceded with an FA invitation (n = 20) and without such an invitation in the control condition (n = 17). On average, relatively little information was collected in the FA phase and far more in the subsequent gradual disclosure phase. However, the FA condition yielded seven confessions, four of which were given already in the FA phase. The No FA condition yielded only two confessions. Other differences in yield were not found. These findings indicate that an FA invitation could lead to some relevant and important information, such as a confession, being gathered already at an early stage of an interview, and that such an invitation does not hamper the gathering of further information later in the interview