Innovative integration of severe weather forecasts into an extended arrival manager

Abstract

The impact of extreme weather on air traffic is a global challenge that results in varying delays to flights depending on climate zone, traffic, and available infrastructure. Due to an observed increase in severe weather events, this impact on air traffic is expected to grow in intensity in the coming years, making it increasingly important to organize airspaces safely and efficiently even under severe weather conditions. In the EU H2020 project "Satellite-borne and INsitu Observations to Predict The Initiation of Convection for ATM" (SINOPTICA), three new meteorological forecasting techniques - PhaSt, RaNDeVIL and WRF-RUC - were developed and tested to better nowcast severe weather events affecting tactical air traffic management operations. The nowcasts are used to organize the approaching traffic by an Extended Arrival Manager (E-AMAN) generating 4D trajectories to efficient detour around severe weather areas in the vicinity of airports. For this purpose, short-range severe weather forecasts with very high spatial resolution were elaborated starting from radar images, through an application of nowcasting techniques combined with Numerical Weather Prediction (NWP) models and data assimilation. This compact nowcast information were integrated into an E-AMAN to support Air Traffic Controllers (ATCO) when sequencing and guiding approaching aircraft even in adverse weather situations. The combination of fast and reliable weather nowcasts with a guidance-support system enables on the one hand the 4D trajectory calculation for diversion coordination around severe weather areas, and on the other hand the visualization of dynamic weather information on the radar displays of controllers. A previous evaluation of the concept by ATCOs showed that the presentation of meteorological information must be compact and concise to not interfere with relevant traffic information on the display. Two severe weather events impacting different Italian airports were selected for validation of the E-AMAN. Combining the Vertical Integrated Liquid and the Echo Top Maximum products, hazard thresholds were defined for domains around the airports. The Weather Research and Forecasting model has been used to simulate the formation and development of the aforementioned convective events. In order to produce a more accurate very short-term weather forecast (nowcasting), remote sensing data (e.g. radar, GNSS) and conventional observations were assimilated by using a cycling three-dimensional variational technique. The validation of E-AMAN system in SINOPTICA project focused on the aspects of feasibility and efficiency and contained two phases. In the first phase, recorded weather data and realistic air traffic were combined and run in a traffic simulation, where the E-AMAN has to organize and to plan the aircraft depending on the measured and forecasted weather. For the evaluation, flight time, track miles and fuel consumption estimation KPIs were applied. In the second phase, various E-AMAN simulation runs were demonstrated to an international controller team for evaluation. The predictions of the three considered forecast models were surprisingly heterogeneous for the same period and area, so that a comparative statement regarding the support quality of the considered E-AMAN within the project is only possible to a limited extent. However, it is indicated that an E-AMAN is very helpful if there is a possibility for large-scale fly-around planning. For this purpose, longer-term and highly precise forecasts that are precisely tailored to Air Traffic Control requirements are essential. The forecast model must correspond to the safety perception of the air traffic controllers and pilots on site, so that they can manage the traffic as efficiently and safely as possible. However, with the help of sophisticated nowcast models and the E-AMAN, SINOPTICA was able to show that it is possible to support controllers and pilots in challenging meteorological situations to guide air traffic safely and efficiently, and thus to make planning more reliable and predictable for all stakeholders on ground and in the air. This contribution presents an overview of the final results of the SINOPTICA project.