Wind Vector Field

A dynamic sculpture called Windswept by artist Charles Sowers showing the vector field of wind direction on the side of the Randall Museum in San Francisco. The description from the artist's website says:

Windswept consists of 612 freely rotating wind direction indicators mounted parallel to the wall creating an architectural scale instrument for observing the complex interaction between wind and the building. Wind gusts, rippling and swirling through the sculpture, visually reveal the complex and ever-changing ways the wind interacts with the building and the environment.

The measurements of such a vector field (including magnitude and direction) can be modeled and analyzed using directional statistics, like the wind swept pine needles of last week.