Tyson Randall
I am a graduate student puruing an M.S. in Environmental Science here at CSU Chico. My thesis research is in exploring fine-scale atmospheric gravity waves in the nocturnal boundary layer above an orchard canopy that were detected by the REAL during CHATS in 2007. The REAL has the unique capability of observing the spatial characterisitics of these waves. During CHATS, in situ data was also collected allowing me to analyze many of the conditions (such as temperature, relative humidity, etc.) supporting these waves and their dynamics(see below).
Currently, I am using autocorrelation and cross-correlation techniques on two dimensional backscatter images to determine the spatial properties of these waves. The autocorrelation gives me a wavelength, cross-correlation gives me a wave velocity (direction and magnitude) and the combination gives me a period, all fundamental quantities to describe wave motion.
More to come...
Email: trandall4@mail.csuchico.edu
An example lidar scan revealing coherent wave-structures. Visit canopy waves website for movies and more about the waves.
I presented my most recent research in a poster in Austin,Texas at the American Meteorological Society's Annual Meeting.
In the summer of 2012, I presented this research in a poster in Boston for the American Meteorological Society's 20th Symposium on Boundary Layers and Turbulence.
Tower Data Example
These plots show the nocturnal canopy gravity waves. They are both at the same time and place showing different dimensions.
27 April 2007
07:53:00-7:57:00 UTC
Above: Vertical velocities from in situ tower data during CHATS. Upward velocities in red, downward are in blue
Horizontal velocities. Upward velocities in red, downward are in blue.
Publications
Randall, T. N. and S. D. Mayor, 2013: Lidar observations of fine-scale internal gravity waves. Poster presentation 715 in Sixth Symposium on Lidar Atmospheric Applications, 93rd Annual Meeting of the American Meteorological Society, 9 January, Austin, TX.
Randall, T. N., E. R. Jachens, and S. D. Mayor, 2012: Lidar observations of fine-scale atmospheric gravity waves in the nocturnal boundary layer above an orchard canopy. Poster Presentation at the American Meteorological Society’s 20th Symposium on Boundary Layers and Turbulence, 9-13 July 2012, Boston, MA.
Mayor, S. D., E. R. Jachens, and T. N. Randall, 2012: Lidar observations of fine-scale gravity waves in the nocturnal boundary layer above an orchard canopy. Poster Presentation P01-15 at the 16th International Symposium for the Advancement of Boundary-Layer Remote Sensing (ISARS), 5-8 June 2012, Boulder, Colorado.
E. R. Jachens, and T. N. Randall, S.D. Mayor, 2012:College of Natural Sciences Poster, 20 April 2012, Chico, CA
Links
Waves webpageMy other webpage