Oregon State University

Early morning fog release

October 19, 2010: We conducted a release of artificially created fog using two fog machines at different locations in close proximity to the fiber array. Individual fog pulses were 20 sec long and spaced 3 min apart throughout the experiment. The video information was recorded with two cameras: one located South-East of the array in about 50 m distance on the ground, and one attached to a pulley system on the tall tower located at about 20 m above ground. 

The sped-up video clearly indicate the presence of meandering motions while the general flow is Northerly. A cold air 'lens' builds up in the shallow gulley, in which the base of the fiber array is located, and sloshes back and forth most likely driven by larger-scale pressure perturbations of unknown origin. The air is strongly stably stratified with a vertical gradient of about +1 K/m. Toward the end of the movie, the surface heating breaks up the stable stratification leading to enhanced turbulent mixing as indicated by the shear driven overturning of larger eddies.

Contact Info

Oregon State University
College of Earth, Ocean, and Atmospheric Sciences
130 Burt Hall
Corvallis, OR,
97331-5503
Copyright ©  2014 Oregon State University
Disclaimer