High temporal resolution monitoring of precipitation in the Basque Country

Precipitation remains as one of the most difficult meteorological variables to measure. In the Basque country case there are two main ways of performing point measurements; with the pluviometers network that has been developed during more than thirty years, and with the new disdrometer network that is being implemented during  these last years.

Here we present the main characteristics of the Basque disdrometer network. This network is based on OTT Parsivel disdrometer, a laser-based optical instrument for simultaneous measurement of PARticle SIze and VELocity of all liquid and solid precipitation. This new instrumentation isincluded in the Basque multipurpose network, providing information for rain-drop distribution, velocities and other derived quantities on a 1-minute basis for different locations all around the territory.  

In this work, we also present the visualization and analysis tool developed for an easy and intuitive exploitation of disdrometer derived data in real time together with information from the network of rain gauges and remote sensing systems (mainly radar). Such tool allows us to analyze in real and in deferred time all the information available in the territory for precipitation characterization at each observation point.

Finally, some aspects of interest are introduced in relation to different measurements obtained with the OTT Parsivel disdrometers at different points of the network during some interesting events. These disdrometers are equipped with two heads, one of which is an infrared laser emitter and the other a receiver that measures the attenuation produced in the light beam by the particles that pass through it. From this information, size, velocity and typology of the meteors, based on a diameter-velocity relationship are derived. Intensity of precipitation, the volume of water per volume of air, visibility or radar reflectivity, among others, are also available.

The effort to increase the understanding of the precipitation characteristics, that affects our territory, and its quantification through the new network of disdrometers, will allow an improvement in impact weather capabilities with a better surface precipitation fields characterization, integrating new data with that coming from radars or satellites. Many others areas of interest such as edafology, hydrology or climate change at local level, would also be positively affected.