Turbulence forecast verification using in-situ Eddy Dissipation Rate observations

In-situ Eddy Dissipation Rate (EDR) observations sampling en-route turbulence has become more commonplace as more aircraft are equipped with the technology. The more objective nature of these observations have lead to greater transition in use of EDR observations to verify turbulence forecasts as opposed to the more subjective Pilot Report (PIREP). Currently, aircraft from United Airlines and Delta Airlines are equipped with technology to observe EDR. Two main topics for use of EDR observations in verification of turbulence forecasts are being explored. First, EDR is being viewed in terms of turbulence events, including onset and cessation, along a flightpath, augmenting the traditional grid-to-point verification. This event-based approach provides a more operationally significant method for analyzing a grid based forecast. Second, the separate sources of EDR observations (i.e. different commercial aircraft) are being intercompared to characterize the differences in sampling techniques and to explore those differences for use in the verification of turbulence forecasts. With greater temporal and spatial resolution, EDR observations allow for greater exploration and better characterization of turbulent events. Verification results of the Graphical Turbulence Guidance (GTG) algorithm will be presented using these approaches in parallel to traditional verification techniques, along with diagnostic results characterizing turbulent events via EDR observations.