The Alaiz Experiment (ALEX17): visualizing the flow in complex terrain with multi scanning lidars

The Alaiz Experiment (ALEX17), located in Navarre (Spain), is a full-scale experiment that aims to peer into the microscale flow of a large-scale and complex topography influenced by mesoscale forcing. The experimental site site consists of a mountain range of 1000m a.s.l with a well-known wind regime. To the North, aligned with the prevailing wind, measurement equipment are located at a valley 500m lower in altitude. The measurement campaign started in November/2017, with an intense observational period (IOP) of six months as well as 1-year of met mast measurements along with long-term means from a reference mast. The multi-lidar scanning patterns can provide 2D and 3D wind reconstruction over a 125m a.s.l. Z-shaped transect 10km long, being a unique feature from this experiment. The intersecting scans used for wind speed reconstruction can also be rendered into virtual met masts. Results show this multi-lidar layout is capable of capturing main flow patterns as speed-ups on ridge tops and valley flow between ridges, with valid data from 100m to 3500m. The presentation summarizes the main layout and results of the experiment, pointing the way to access the open-source dataset of all equipment and documentation of ALEX17