Topography with high mountains and steep inclinations – albeit are beautiful landscapes – but can add complexity when dealing with wind measurements like direction and speed. Since ridges and mountains are barriers to the horizontal movement of air, the wind is deflected over them adding to the local up-slope convective winds from the surface heating by the sun.
At Vaisala, we have encountered clients over the years that have struggled with complicated wind measurements in complex terrains. Luckily, many of them have leveraged the capabilities of the Vaisala WindCube® wind lidar to solve these challenges in making the invisible visible – and simplify managing wind research in complex terrains.
For this project, Kjeller Vindteknikk had to do something neither they nor anyone else has ever done: provide accurate wind and turbulence data to enable record-setting bridge designs that will span the Halsafjorden and Sulafjorden crossings in Norway.
Unfortunately, traditional met mast installation was not feasible. For each bridge site, two met masts would be required in a fjord 3km wide, with water depths reaching 550m. Further, wind profiles must be measured at different points along the proposed bridge routes to create sufficient turbulence and differential wind load information. The only suitable technology to provide this data is scanning wind lidar.
Learn how Kjeller positioned itself to deliver safe, reliable (and record-setting) bridge designs in one of the most challenging Nordic environments.
KITcube is an advanced integrated atmospheric observation system, which allows for a complete probing of the atmosphere within a volume of around 10x10x10 cubic kilometers. It combines different in situ and ground-based remote sensing instruments, which cover complete turbulence, convection, clouds, and precipitation processes chains. KITcube was born at Karlsruhe Institute of Technology, KIT for short.
For example, the German Urban Climate Under Change [UC]2 campaign in the Stuttgart basin in southwest Germany uses the Doppler wind lidar measurements to resolve flow features in complex urban environments. Its target area has mountainous terrain and is well-known for episodes with poor air quality. Due to the terrain surrounding the city, different thermally driven circulations develop. KIT deployed three WindCube Scan lidars and installed them at opposing slopes overlooking the Neckar Valley and the outflow region from the Stuttgart basin. The lidars were installed roughly at the same height and they performed scans at around 70 meters above the valley topography. The WindCube Scan investigated the mesoscale structure of the horizontal flow in the valleys concerning the time of the day, stratification, and wind aloft.
Watch the full webinar to see Dr. Bianca Adler describe the campaign in more detail
Dr. Nevio Babic is a researcher at KIT who conducted a lidar measurement campaign, studying cross valley winds in the Inn Valley, in the Austrian Alps as part of the crosswind experiment. This campaign launched in 2019 and was investigated by dual Doppler lidar measurements. The team at KIT developed the experiment to explore and investigate cross-valley flows. They focused on three locations with three different WindCube lidars.
The lidars performed overlapping range height indicator scans, Overall, the crossing provided a comprehensive 3D perspective on the thermodynamic state of the mountain boundary layer in the Inn Valley. And specifically, the three WindCube systems proved invaluable in sampling this cross-valley floor structure.
Watch the full webinar for more interesting data from Nevio and the CROSSINN campaign from the Karlsruhe Institute of Technology (KIT).
Even though certain terrains add complexity to wind measurement, the future is bright with insights when it comes to Doppler wind lidars. Rigorously validated and extraordinarily flexible, these devices are disrupting and improving industries around the world.
Find more information on WindCube lidars and resources on the industries they serve to discover how this data can serve you.