The NSSL winter hydrometeor classification ground truth program: public involvement in science

During the winter of 2006-2007, a concerted effort was made by the National Severe Storms Laboratory to collect polarimetric radar data using the KOUN radar during winter precipitation events. Simultaneously, observations of precipitation type within a radius of 150 km of KOUN were solicited from the public. Public response has resulted in about 2500 individual observations of winter precipitation type over the course of three major events. These data are intended to be used to both verify the current hydrometeor classification algorithm performance in winter weather events, and to enhance the algorithm's performance.

This paper discusses the nature of the ground truth data collected, its overall utility, the nature and scope of quality assurance checking, how event timing affects observation availability, how best to solicit and encourage public participation, and examples of how the data are being used.