Two publications involving my thesis ("Quantitative Analysis and 3D Visualization of NWP Data Using Quasi-Geostrophic Equations") are being developed: The Minimum Length Scale for Evaluating QG Omega Using High Resolution Model Data which is in press with Monthly Weather Review and "Investigation of the Three-Dimensional Structure of the Level of Non-divergence."
The quasi-geostrophic (QG) system of equations is a well studied aspect of synoptic-scale meteorology; however, I am investigating two unresolved questions.
At what horizontal scale lengths does QG omega no longer provide useful diagnostic information, and what if any methods can be used to extract synoptic-scale vertical motion from mesoscale models?
To answer both questions I calculate the QG omega equation on 28 cases from the operational North American Mesoscale (NAM) model.
Modifying the distances between finite difference calculations all us to ascertain appropriate length scales to diagnose QG vertical forcing.
We find the appropriate length scale to be around 240 km by correlating QG omega back to vertical motion provided by the NAM.
This does agree with theory but is somewhat larger than studies on coarser datasets.
The code and data for the project with readme files are provided as a zip file.
AMS 2017 Poster The Minimum Horizontal Length Scale When Evaluating Quasi-Geostrophic Omega presents results from the recently published paper.
And an initial AMS poster, Quantitative Analysis and 3D Visualization of NWP Data Using Guasi-Geostrophic Equations, was presented as part of the thesis work.
A NWA poster from 2011 looks at the Visualization of Divergence and Vorticity in Three Dimensions
Education and 3D Visualization
I have been investigating the 3D patterns of divergence and vorticity in synoptic systems to aid in visualization in the classroom.
I am in the early stages of a manuscript that links features commonly used to deduce vertical motion using quasi-geostrophic, two-dimensional analysis to equivalent features in three-dimensional analysis.
Below is an example of what is possible with a 3D visualization package.
Pictured are the jet stream, vorticity, and vertical motion simultaneously.
Each of these fields is inherently three-dimensional, and so are excellent candidates for introduction to the classroom environment.
Fig. 3: 3D contours of the jet stream (55 m/s in yellow, 75 m/s in orange), vorticity (0.0015 /s in green), and omega (-0.5 Pa/s colored by pressure with blue at 200 hPa and red at 900 hPa) on 1800 UTC 12 December 2010.
For more, see my poster at the National Weather Association Annual Meeting in October 2011.