Vertical Structure of Coastal Wind Regimes: Four Years of Continuous SODAR Observations at Split Airport

Split International Airport (LDSP), situated on the eastern Adriatic coast, presents a complex meteorological environment for aviation operations. The airport's location at the base of the Dinaric Alps creates a unique intersection between synoptic-scale flows and sub-mesoscale coastal circulations.

Following a collaboration between the University of Split, Split Airport, and Croatia Control (air navigation service provider) continuous SODAR (SOnic Detection And Ranging) measurements have been operational since June 2022 at the airport location. The primary objective of this university project was the collection of research data, but since it was installed at the airport, it’s real-time measurements can also provide very useful information for aviation forecasters.

The data is collected using a Scintec MFAS (Multi-Frequency Flat Array SODAR). While the instrument is capable of a vertical range up to 1000 m, it is optimized for high-resolution monitoring within the lowest 500 m of the troposphere—the most critical zone for aircraft approach and departure. Data is processed at 20-minute intervals, providing a detailed vertical profile of wind direction and speed.

The four-year dataset captures the seasonal and diurnal variability of the four dominant local wind regimes:

• Bora (Bura): A gusty north-easterly wind, often associated with severe mechanical turbulence due to the nearby mountains.
• Sirocco (Jugo): A moist, south-easterly flow, sometimes with wind speeds above 25m/s in the 500m surface layer.
• Sea-Breeze (Maestral): A predictable but significant south-westerly coastal circulation that dictates runway changes from standard instrumental approach to a more complex visual approach from north-east, due to mountain proximity on that side of the airport.
• North-westerly gap flow : Katabatic flow from the mountain gap north-west of the airport, but also a tramontana, typical post-frontal flow (synoptic + orography).

Moreover, in aviation meteorology information from SODAR instrument can be very useful for detecting vertical wind shear.

This poster will present some typical examples of wind profiles at Split airport, wind roses at different altitudes  (e.g., 50m, 150m, 300m), and examples of significant wind shear episodes.

These findings emphasize the necessity of ground-based remote sensing for enhancing safety and operational efficiency at topographically challenged coastal airports.