Trajectory sensitivity to rawinsonde data resolution

Abstract

Meteorological measurements collected during the Cross Appalachian Tracer Experiment (CAPTEX) were used to evaluate the sensitivity of trajectory calculations to variations in the spatial and temporal density of rawinsonde data. Data resolution was systematically adjusted in order to separately evaluate the effects of enhanced spatial and temporal resolution. Variable mixed layer, constant layer, and constant level trajectories were more sensitive to increases in spatial resolution than to increases in temporal resolution. For mixed layer, 0-400-m layer and 400-m level trajectories, sensitivity to combined increases in both spatial and temporal rawinsonde data resolution was dominated by the effects of spatial resolution alone. This dominance was not observed for trajectories calculated at higher levels and layers.Trajectory case studies corresponding to two CAPTEX tracer releases were presented. These examples illustrate the potential effects of a single additional measurement at an existing National Weather Service rawinsonde station, and the importance of specifying the initial transport wind accurately.